Environmental Engineering
I. Alazzam; K. Shatanawi; R. Al-Weshah
Abstract
BACKGROUND AND OBJECTIVES: Jordan is among the most water-scarce countries in the world. The scarcity of water resources in Jordan is driving the development and advances of non-conventional water techniques that enable integrated management of water resources in addressing water scarcity challenges ...
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BACKGROUND AND OBJECTIVES: Jordan is among the most water-scarce countries in the world. The scarcity of water resources in Jordan is driving the development and advances of non-conventional water techniques that enable integrated management of water resources in addressing water scarcity challenges and promoting sustainable water use. Water harvesting of rainwater and fog techniques is one of the viable solutions to mitigate the water scarcity effects in Jordan. This study aimed to evaluate the quantity of rainwater and fog collected through the utilization of solar panels, while also conducting a feasibility analysis on the economic and environmental aspects of employing solar panels for rainwater and fog harvesting in a solar farm situated in Jordan.METHODS: In the present study, an in-situ experiment is conducted to investigate rainwater and fog harvesting from solar panels' surfaces that are widely spread in Jordan. The solar farm situated in Hai Al Sahabah, south of Amman, Jordan, incorporates an experimental arrangement that involves the installation of gutters, pipes, and water tanks beneath two solar panel samples. These panels have a total area of 4 square meters and will be monitored for a duration of 60 days.FINDING: The results of the experiment show that the total quantity of the harvested rainwater using two solar panels was 444 liters ranging from 0.8 liters per day to 117.66 liters per day, and the total harvested fog quantity was 28 liters ranging from 0.25 liters per day to 9.75 liters per day. The multilinear regression technique was employed to establish a correlation between the amount of harvested water and the crucial factors of wind direction, wind speed, relative humidity, and temperature at the solar farm. The analysis of the findings revealed a significant relationship between these variables. These relationships can be generalized to provide an estimation for the quantity of rainwater and fog harvesting in other locations. The quantity of harvested rainwater was primarily influenced by wind speed and direction, the quantity of harvested fog was mainly affected by relative humidity and temperature. The current study aims to analyze and deliberate on the collected amounts of water obtained through rainwater and fog harvesting from solar panels. The viability of implementing the method of rainwater and fog harvesting from solar panels will be examined in terms of economic and environmental factors.CONCLUSIONS: The quantity of rainwater gathered in this research with just two solar panels shows great potential for widespread use as a supplementary water supply. This method of rainwater and fog harvesting can be effectively applied to solar power plants which are widely spread in Jordan for use in solar panel cleaning, agriculture, groundwater recharge, and reducing stormwater discharge to assess and manage the risk of environmental damage. Rainwater and fog harvesting systems offer a higher level of efficiency and cost-effectiveness compared to other methods, especially when seamlessly integrated into the infrastructure of solar power plants. The benefits of solar panels by producing clean energy are not negotiable but combining energy production with water harvesting in solar power plants would offer even more advantages in enhancing the global environmental situation.
Environmental Engineering
V.G. Shcherbak; Y.I. Danko; S. Tereshchenko; O. Nifatova; N. Dehtiar; O. Stepanova; V. Yatsenko
Abstract
BACKGROUND AND OBJECTIVES: In the context of war, rural areas of Ukraine have encountered serious environmental challenges that threaten not only the environment but also the resilience of communities. This study aims to examine the impact of circular economy and inclusion on reducing the risk of ecological ...
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BACKGROUND AND OBJECTIVES: In the context of war, rural areas of Ukraine have encountered serious environmental challenges that threaten not only the environment but also the resilience of communities. This study aims to examine the impact of circular economy and inclusion on reducing the risk of ecological threaten, addressing resource usage issues, and restoring ecology in rural areas during wartime. The objectives include analyzing the potential of the circular economy and inclusive practices to solve the mentioned problems.METHODS: Various methods were used to analyze the impact of circular economy and inclusion on the environmental situation in rural areas. The foundation of the research was based on reviewing scientific literature and analyzing previous studies, which allowed for assessing the potential impact of these factors on the environment. The main methods applied included quantitative data analysis through regression modeling, which helped identify the relationship between the level of inclusion and circular economy practices with changes in the level of ecological threaten. Additionally, the use of taxonomy allowed determining the level of ecological threaten, while cluster analysis was used to distribute territories based on the level of ecological threaten ecocide. Factor analysis helped to understand how circular economy measures and inclusion affect ecological threaten, and regression analysis was used to confirm the validity of the research hypotheses.FINDINGS: The study demonstrates integrating circular economy principles with active community engagement significantly mitigates ecological threats in wartime rural Ukraine, achieving a 45 percent risk reduction. Direct positive impact of circular economy practices and inclusivity on environmental health, marking a 30 percent ecological improvement, was discovered. Research highlights innovations and inclusive practices enhance biodiversity by 25 percent and boost agricultural productivity by 20 percent. These findings underline the urgent need for a shift towards a sustainable management model combining circular economy principles with extensive social inclusion, essential for ecological resilience and rejuvenation of rural Ukrainian areas amidst conflict.CONCLUSION: Implementing circular economy and inclusivity in rural Ukraine reduces ecological threats by 45 percent, enhancing biodiversity and agricultural productivity. Circular economy and inclusion are key strategies for ensuring ecological resilience and restoration in rural areas of Ukraine during war time. The implementation of circular economy, waste reduction, resource reuse, development of low-carbon technologies, and active community engagement in environmental initiatives can contribute to the resilience and recovery of affected regions.
Environmental Engineering
Naharuddin .; Rukmi .; S.D. Massiri; B. Toknok; Akhbar .; I.N. Korja
Abstract
BACKGROUND AND OBJECTIVES: Peak flow in watershed is important in designing and controlling soil erosion, as well as assessing the potential water yield. It also serves as a basis for assessing and managing the risk of environmental damage. However, there is no accurate information on peak flow to ensure ...
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BACKGROUND AND OBJECTIVES: Peak flow in watershed is important in designing and controlling soil erosion, as well as assessing the potential water yield. It also serves as a basis for assessing and managing the risk of environmental damage. However, there is no accurate information on peak flow to ensure sustainable management and conservation of Wuno Sub-Watershed in Palu Watershed which serves as a buffer for the capital of Central Sulawesi Province. Therefore, this study aimed to assess and determine the potential runoff and peak flows in watershed using soil conservation service-curve number.METHODS: Soil conservation service-curve number method was calculated to analyze rainfall from runoff as a function of cumulative rainfall, land use, soil type, and humidity. This method was developed by the United States Soil Conservation Service in 1972 and applied in this study with due consideration for several variables, including (a) land use classification and intensity for settlements, rice fields, plantations, rivers, etc., (b) basic physical conditions of the area such as rainfall and hydrology, as well as (c) classes of soil hydrology significantly influencing carbon-nitrogen value.FINDINGS: The result showed that carbón-nitrogen values for all types of land use or cover were in normal conditions from 5 to 25 years. Moreover, carbón-nitrogen range was observed to have significantly large quantitative consequences on direct runoff. The trend showed the need for precision and effectiveness in planning watershed management and conservation. Soil conservation service also had a positive influence on land use, specifically runoff, as observed in carbón-nitrogen values for return periods of 2, 5, 25, and 100 years. However, several other factors were identified to influence land use such as land cover and soil texture.CONCLUSION: Soil Conservation Service presented an analysis of how land use affected runoff, specifically with a focus on carbon-nitrogen values. Land use was not only affected by carbon-nitrogen values but other factors such as land cover and geomorphometric properties. The trend showed the need for a more comprehensive exploration of soil conservation service-curve number method in accurately predicting runoff patterns in sub-watershed areas to ensure effective and sustainable management and conservation practices.
Environmental Engineering
S. Mokatip; K. Chunkao; W. Wararam; S. Bualert; O. Phewnil; T. Pattamapitoon; N. Semvimol; P. Maskulrath; P. Rollap; S. Thaipakdee
Abstract
BACKGROUND AND OBJECTIVES: Domestic wastewater pollution in Thailand presents challenges due to limited space and a high concentration of point source effluents. This phenomenon often leads to domestic wastewater exceeding the capacity of local treatment systems. This study aims to expand the knowledge ...
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BACKGROUND AND OBJECTIVES: Domestic wastewater pollution in Thailand presents challenges due to limited space and a high concentration of point source effluents. This phenomenon often leads to domestic wastewater exceeding the capacity of local treatment systems. This study aims to expand the knowledge gained from The King’s Royally Initiated Laem Phak Bia Environmental Research and Development Project by evaluating the treatability of municipal wastewater. It utilizes a constructed wetland system in conjunction with a transfer and point source system. After the implementation of this primary system, the reduction in highly contaminated domestic wastewater could enhance the treatment loading of other secondary treatment systems or even facilitate its release into natural pathways.METHODS: In the sampling collection process, the dynamics of the collection points were categorized into three different zones: 1) the point sources of domestic wastewater within a municipality, where 15 sample points were selected to represent the municipality; 2) the collection pond within the municipality and the transfer pipeline, comprising three collection points of the system; 3) the constructed wetland treatment system, where five water samples were collected in relation to the length of the existing 100-meter plot. The water samples were collected using four 1-liter polyethylene bottles. The analysis parameters were the biological oxygen demand, total nitrogen, nitrate, total phosphorous and phosphate, and other parameters related to domestic wastewater treatment efficacy.FINDING: This study reveals that the domestic wastewater in Phetchaburi Province initially has a high organic content, leading to a biochemical oxygen demand: nitrogen: phosphorous ratio of 100:2.5:0.2 favoring anaerobic degradation. This ratio shifts in the constructed wetland system, located 18.5 kilometers away, to 100:10.5:2.3, promoting anaerobic treatment. The system shows high efficacy, with 81.4, 50.0, and 58.3 percent removal rates for biochemical oxygen demand, nitrogen, and phosphorus, respectively. This efficacy corresponds to a notable reduction in average biochemical oxygen demand from 740.0 to 9.7 milligrams per liter. Moreover, changes are observed in total nitrogen content, shifting from 20.8 to 2.8 milligrams per liter, in the system’s effluent. While lastly, the total phosphorous decreased from 2.75 to 0.60 milligrams per literCONCLUSION: This treatment method can be effectively applied to small-scale constructed wetland systems within households. The recommended hydraulic retention time is between 29 and 60 hours under anaerobic conditions and 3 days under aerobic conditions. The changes in the composition of municipal wastewater, which is highly organic, support the use of both degradation processes. The knowledge and application of the constructed wetland system could be suggested for the primary treatment system of domestic wastewater within municipalities, given that this system would provide support to the central wastewater treatment system for enhanced efficacy.
Environmental Engineering
M.G. Nugraha; A. Sharfan; V.S.Y. Prakoso; M. Hidayat; H. Saptoadi
Abstract
BACKGROUND AND OBJECTIVES: Agriculture significantly contributes to global economies, yet it concurrently generates waste in the form of crop residues. Conventional waste disposal methods, such as open burning, contribute to atmospheric particulate emissions, impacting air quality regionally and potentially ...
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BACKGROUND AND OBJECTIVES: Agriculture significantly contributes to global economies, yet it concurrently generates waste in the form of crop residues. Conventional waste disposal methods, such as open burning, contribute to atmospheric particulate emissions, impacting air quality regionally and potentially globally. Exposure to these pollutants poses substantial risks to human health, including respiratory illnesses, cardiovascular diseases, and premature mortality. This study aims to assess the environmental implications of biomass waste combustion in Yogyakarta, Indonesia. Additionally, the study aims to investigate potential enhancements in biomass burning practices through experimental campaigns conducted in both open and closed burning conditions.METHODS: The study evaluates Yogyakarta's regional air quality using data from the Meteorology, Climatology, and Geophysical Agency for the period spanning from 2020 to 2022. Emission factors from open and closed burning practices are assessed using an experimental furnace equipped with real-time combustion parameters monitoring, including temperature, particulate matter concentration, and oxygen and carbon dioxide levels. The openburning experiments involve various combustion conditions for bagasse, leaf litter, and rice straw, encompassing variations in ignition location, initial mass, and air supply methods. Closed burning experiments explore variations in reloading frequency, air-fuel ratio, and air staging.FINDINGS: Yogyakarta's air quality assessment involves comparing rice harvest trends with atmospheric particulate matter concentrations during 2020-2022. Open burning practices in Yogyakarta exhibit a correlation with heightened rainfall, which in turn leads to higher emissions from April to August due to reduced rain frequency. Experimental campaigns have revealed that open burning practices result in a significant amount of emissions, ranging from 3 to 29 grams of particulate matter per kilogram of biomass.. Meanwhile, the utilization of closed combustion systems has been demonstrated to decrease the emission factor within the range of 0.37 to 1.98 grams of particulate matter per kilogram of biomass. This highlights the importance of operating conditions altering particulate emissions. Moreover, the emission reduction by factor nine, emphasizing the efficacy of controlled combustion techniques in comparison to open burning methods, in mitigating particulate emissions.CONCLUSION: The study identifies that greater initial biomass mass, mid-ignition, and natural airflow contribute to lower emissions in open burning practices. o achieve optimal closed combustion conditions, it is recommended to reload biomass more frequently with100 percent excess air allocation, distributing 30 percent to primary air and 70 percent to secondary air. These findings not only propose better practices for disposing of agricultural waste and minimizing air pollution but also emphasize the potential of utilizing biomass waste for energy conversion.
Environmental Engineering
O. Phewnil; T. Pattamapitoon; N. Semvimol; W. Wararam; K. Duangmal; A. Intaraksa; K. Chunkao; P. Maskulrath; S. Hanthayung; P. Wichittrakarn
Abstract
BACKGROUND AND OBJECTIVES: Landslide disasters in Thailand between 1970 and 2011 revealed a notable pattern: they primarily originated on mountain slopes, distinguished by a deeper soil profile. This soil profile comprised clay loam and sandy loam textures and was situated over aged geological formations ...
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BACKGROUND AND OBJECTIVES: Landslide disasters in Thailand between 1970 and 2011 revealed a notable pattern: they primarily originated on mountain slopes, distinguished by a deeper soil profile. This soil profile comprised clay loam and sandy loam textures and was situated over aged geological formations of granite and shale rocks. The affected areas included the southern and northern provinces of Thailand.This study investigated the consequences of landslide hazards on stream water and sediment quality in two watersheds: the Mae Phul–Mae Prong watershed in Uttaradit province, the northern part of Thailand, and the Klong Kram watershed in Surat Thani province, the southern part of Thailand. These watersheds had experienced recurrent landslides, primarily on mountain slopes characterized by deep clayey and sandy loam soils over old granite and shale rock types as well as old granite limestone.METHODS: During wet and dry periods in April and November 2015, 108 samples were collected from 18 stations (9 stations in the Klong Kram watershed and 9 stations in the Mae Phul–Mae Prong watershed). These samples included upland soil, stream water, and sediments. For upland soils, 1 kilogram samples were collected through auger and V-shaped pit techniques using a stainless-steel spade, with composite sampling conducted at 0–30 centimeters across all 18 stations. Stream water was collected in one part using a 1-L polyethylene bottle at 30 centimeter from the stream layer, while other samples were compositely collected in sterilized glass bottles to determine coliforms. Soil and sediment samples were compositely collected from the bottom using a stainless-steel spade. All samples were stored at 4 degrees Celsius and transported to a laboratory for analysis. The insight gained from these collection efforts elucidated the dynamics of landslide impacts at the spatial scale for the two watersheds.FINDINGS: Most water samples met Thai surface water quality standard for various parameters; however, microbial contamination of the water samples attributed to community activities along stream banks was detected. Notably, arsenic was consistently detected in upland soil, stream water, and sediment samples. For Uttaradit, the average arsenic concentrations were 0.22 ± 0.09 milligram per kilogram, 0.01 ± 0.14 milligram per liter, and 9.74 ± 4.42 milligram per kilogram in upland soil, water, and sediment samples, respectively. For Surat Thani, arsenic concentrations were 87.63 ± 208.83 milligram per kilogram, 0.01 ± 0.01 milligram per liter, and 19.44 ± 36.38 milligram per kilogram in upland soil, water, and sediment samples, respectively, particularly near landslide scars where the arsenic concentrations were significantly higher in sediments and upland soils compared with stream water, highlighting the role of landslides near streams. These data suggest that sediment transport from upland soil in the landslide scar into stream water affects water quality, particularly in terms of arsenic concentration near the landslide scar, often surpassing natural standards.CONCLUSION: The study concluded that stream water was directly affected by landslides as these watersheds were unsuitable for consumption due to arsenic and microbial contaminations. This conclusion emphasizes the critical need to incorporate landslide hazard considerations into watershed management practices to safeguard downstream communities and preserve water resources.
Environmental Engineering
C. Tudsanaton; T. Pattamapitoon; O. Phewnil; W. Wararam; K. Chunkao; P. Maskulrath; M. Srichomphu
Abstract
BACKGROUND AND OBJECTIVES: Community domestic wastewater contains organic substances that can be decomposed through natural processes. Treatment using oxidation pond systems is popular in tropical zones because these locations provide a climate suitable for the growth and organic decomposition activities ...
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BACKGROUND AND OBJECTIVES: Community domestic wastewater contains organic substances that can be decomposed through natural processes. Treatment using oxidation pond systems is popular in tropical zones because these locations provide a climate suitable for the growth and organic decomposition activities of various bacteria that remove organic contaminants from wastewater. Given that bacteria play an important role in the biodegradation of organic substances in wastewater treatment plants, their degradation activity is used as an indicator of water quality. The purpose of this study is to examine the vertical variability of bacteria in natural treatment oxidation ponds in tropical zones.METHODS: Wastewater samples were collected from an oxidation pond at 3 different depths (0–0.6, 0.6–1.5 and more than 1.5 meter), and their chemical, physical and biological qualities were analysed. Next-generation sequencing techniques were used to identify bacterial diversity, and the water quality at each depth was applied as an indicator of bacterial degradation activities.FINDINGS: Community domestic wastewater contained 10 major bacterial phyla that differed at different depths. Amongst these phyla, the Actinobacteriota dominated (25.35 to 28.23 percent), followed by Cyanobacteria (19.49 to 21.57percent), Planctomycetota (15.50 to 17.41 percent), Firmicutes (9.97 to 10.79 percent), Proteobacteria (9.73 to 10.79 percent), Verrucomicrobiota (6.47 to 7.69 percent), Chloroflexi (2.79 to 2.99 percent), Bacteriota (0.96 to 1.41 percent), Acidobacteriota (0.70 to 0.80 percent) and SAR324 clade (marine group B) (0.69 to 0.61 percent). Four organic substances were found in contaminated domestic wastewater. 1) Photosynthetic cyanobacteria and phytoplankton performed aerobic degradation and accounted for the dissolved oxygen levels of 7.76, 7.45 and 7.42 milligrams per liter, respectively at various depths along the vertical profile. 2) Bacteria and archaeans that participate in carbon compound treatment included Planctomycetes, Verrucomicrobiota, Bacteroidota and Euryarcheota. These bacteria exhibited a treatment efficiency for biochemical oxygen demand and low abundance at all depths. Biological oxygen demand increased to 23.11, 24.27 and 34.48 milligrams per liter with depth. 3) Nitrogen-cycling bacteria included nitrifying and denitrifying bacteria. They belonged to the Actinobacteriota, Planctomycetota, Firmicutes, Verrucomicrobiota, Chloroflexi, Bacteriota, Protrobacteria and Acidobacteriota phyla. They exhibited an ammonia-nitrogen treatment efficiency of 91.73 percent. 4) Phosphorus cycling–related bacteria in the Actinobacteriota phylum presented the orthophosphorus treatment efficiency of 65.41 percent.CONCLUSION: The results of this study suggested that bacterial communities did not significantly differ along oxidation depth because they work together with chemotrophs, which participate in organic substance decomposition, and phototrophs, which are involved in oxygen generation and nutrient removal. All of the bacteria found in domestic wastewater benefit and support oxidation pond systems in tropical zones. Anaerobic bacteria can be found in wastewater and used in treatment systems due to their protective mechanisms against oxygen toxicity and self-repair mechanisms. The knowledge gained from this study can be used as a reference in future works on natural wastewater treatment systems.
Environmental Engineering
S. Sinworn; N. Viriyawattana
Abstract
BACKGROUND AND OBJECTIVES: The fishery workers are affected by the noise produced by motorboats, which is caused by long-term (more than 7 hours per day), exposure to high frequencies and hazardous noise levels. The detrimental impact of the loud noise emitted by small boat engines affects the hearing ...
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BACKGROUND AND OBJECTIVES: The fishery workers are affected by the noise produced by motorboats, which is caused by long-term (more than 7 hours per day), exposure to high frequencies and hazardous noise levels. The detrimental impact of the loud noise emitted by small boat engines affects the hearing abilities of fishermen in Thailand has been well-documented. In light of this, the primary aim of the present study was to assess the potential hazards associated with noise exposure and develop an effective silencer that can effectively mitigate the noise generated by fishing boats. The study was conducted in Songkhla Lake, located in Thailand, providing a suitable setting for the current study.METHODS: During an 8-hour work period, 300 sample fishers were monitored using sound-level and noise-dose meters. Their response to noise was evaluated through an audiometry test and a questionnaire. Furthermore, a silencer was engineered to decrease the noise emissions from boat engines. Utilizing the solid work technique, the exhaust silencer was designed based on a model of the internal exhaust pressure. The sound level at the end of the exhaust silencer pipe was determined by employing a sound meter and recording it at a speed of 4,000 revolutions per minute. The designed silencer was installed on the exhaust pipe of the boat engine to align with the current operation of the engine. The objective was to measure the variation in noise levels before and after the installation of the silencer. The sound level meter of type I, equipped with a weighted circuit incorporating an A network (weight A), closely resembles the auditory response of the human ear to sound. Prior to assessing the noise produced by the engine, it was ensured that the engine had been running for a minimum of 5 minutes. The sound level of the small boat's engine was then measured using a type I sound-level meter positioned at a 45-degree angle behind the engine, and at a distance of 0.5 meter.FINDINGS: The results indicated that evaluating the risks associated with being exposed to high levels of noise from boat engines had an impact on the auditory capacity of fishermen. The right ear was more severely damaged than the left at frequencies of 6,000 (23 people) and 8,000 (20 people) Hertz at sound levels of 85 decibels A and above. This data is valuable for the development of a silencer aimed at mitigating sound pressure levels that impact the loudness of sound across different frequency levels, considering a boat engine's maximum acceleration of 4,000 revolutions per minute through the application of solid design principles. Subsequently, the silencer will be tested on Thai fishermen who are regularly exposed to noise, demonstrating a reduction in engine noise of over 23 decibels A within the frequency range of 100 to 10,000 Hertz.CONCLUSION: The auditory abilities of fishermen are adversely impacted by the intensity and high pitch of the noise emitted by small boat engines. The solid design technique is employed to create a silencer for a boat engine with a maximum acceleration of 4000 revolutions per minute, operating at frequency levels of 2000, 3,000, 4,000, 6,000, and 8,000 Hertz. Exposure to loud noise can pose a significant risk to the hearing health of fishermen. However, their safety can be ensured by implementing effective measures to reduce the loudness by more than 23-42 decibel A. By employing such work practices, the noise levels experienced by fishermen can be kept below the hazardous threshold of > 85 decibels A.
Environmental Engineering
M.D. Teweldebrihan; M.O. Dinka
Abstract
BACKGROUND AND OBJECTIVES: River basin ecology changes frequently when water resources are developed more. In order to meet human needs, the influence of climate change on river flow and hydrological structures should be understood. Population growth, corresponding economic expansion, and irrigation-related ...
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BACKGROUND AND OBJECTIVES: River basin ecology changes frequently when water resources are developed more. In order to meet human needs, the influence of climate change on river flow and hydrological structures should be understood. Population growth, corresponding economic expansion, and irrigation-related factors for food production all contribute to rising water demand. Consequently, the water availability becomes a scarce resource, when the water demand exceeds the supply. Hence, the understanding the interaction between water, ecosystem and society is a key factor in sustainable water resource development, management and utilization.METHODS: This study evaluates the effects of climate change on the water resource development of the Dhidhessa River Basin. The degree of hydrologic modification was estimated using the Indicator of Hydrologic modification programs. Based on the analysis, the study looked into how variations in rainfall and temperature might affect the river’s flow and Dhidhessa basin. Stakeholder analysis was used to identify seven types of stakeholders who expressed interest in the Dhidhessa sub basin.FINDING: The results indicate that the basin experienced a decrease in water level and river flow as a result of climate change. This drop-in water level and river flow can be attributed to the anticipated change in climate caused by variations in rainfall. The Dhidhessa River Basin, located near the Dembi gauge station, was particularly vulnerable to these changes in flow. Interestingly, the degree of flow alteration was found to be relatively low throughout most of the months. In terms of stakeholder distribution, municipal and community governments accounted for 17.3 percent and 25.4 percent, respectively. Additionally, organizations with investors, ministries, and certain government agencies represented 37.4 percent of the articles, while foreign actors and religious organizations accounted for 19.9 percent.CONCLUSION: The research findings indicate that the water balance in the Dhidhessa basin may be affected by climate change in the coming century. Thus, the variation in rainfall and temperature might affect the river flow. However, it is impossible to determine this change's direction definitively until the model results are assessed under various scenarios. Therefore, the virtual future of socio-hydrologic assessment and better integration of stakeholders is needed to understand the dynamics in the basin for sustainable water resource development and management.
Environmental Engineering
T. Handayani; I.N. Djarot; N. Widyastuti; F.D. Arianti; A. Rifai; A.I. Sitomurni; M.M.A. Nur; R.N. Dewi; N. Nuha; J. Haryanti; D. Pinardi; Y. Suryana; A. Aziz; E. Syamsudin; T. Rochmadi; P.A. Lomak; A. Hadi; M.D. Pertiwi; E. Yuniastuti; N.A. Putri
Abstract
BACKGROUND AND OBJECTIVES: During this energy transition, research is being done to develop sustainable ways to support the shift to a decarbonized energy and production system. These ways include using renewable energy sources to promote circularity in products, green technologies, and safer procedures. ...
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BACKGROUND AND OBJECTIVES: During this energy transition, research is being done to develop sustainable ways to support the shift to a decarbonized energy and production system. These ways include using renewable energy sources to promote circularity in products, green technologies, and safer procedures. Anaerobic digestion of palm oil mill effluent is a beneficial process for generating biogas, while the waste can also be utilized as fertilizer. The biogas can be further refined into biomethane, a valuable resource commonly used in transportation and power generation. The objective of this study is to examine the enhancement of biogas from Palm oil mill effluent and the elimination of sludge nutrients by utilizing microalgae Chlorella vulgaris. The microalgae will be cultivated in a modified photobioreactor to enhance the capture of carbon dioxide.METHODS: The study utilized anaerobic batch reactor digesters. A modified photobioreactor, consisting of two columns separated by a membrane, was developed for the technological advancement of biogas upgrading, specifically for carbon dioxide capture and biogas upgrading. A technological gap in biogas upgrade technology innovation is filled by the improved photobioreactor. To optimize the bio-fixation of carbon dioxide from flue gas, it is essential to carefully select a suitable strain of microalgae that possesses both a strong ability to absorb carbon dioxide and a high tolerance to varying concentrations of this gas. By choosing the right strain, the efficiency of carbon dioxide removal can be significantly enhanced. Since Chlorella vulgaris microalgae have demonstrated this potential, they were chosen for this investigation. Microalgae also play a role in removing nutrients contained in the sludge. FINDINGS: Numerous chemical and biological methods have been used to upgrade biogas. Results of biological upgrading of biogas from palm oil mill effluent have been reported, with carbon dioxide removal reaching 89 percent until the methane concentration of the biogas is upgraded to 84 percent. The highest biomass of 1,835 grams per liter was achieved by culturing the microalgae Chlorella vulgaris in laboratory-scale photobioreactors. In this study, the application of 15 percent volume per volume biogas with an optical density of 0.4 was found to be optimal for the growth of the microalgae. The cultivation period lasted for 14 days. The peak biomass production was observed due to the achievement of a remarkable 98 volume per volume efficiency in carbon dioxide removal, which subsequently led to a significant rise in methane content, reaching 60 percent. The enhanced biogas achieved a peak methane content of 98 percent, indicating a significant improvement in quality.CONCLUSION: The findings of this study, conducted using a modified photobioreactor, indicate that Chlorella vulgaris demonstrated high efficacy in the removal of carbon dioxide, with a rate of up to 90 percent. Additionally, it exhibited remarkable performance in upgrading biogas derived from palm oil mill effluent, achieving a conversion rate of up to 98 percent. The optical density of microalgae at 0.4 played a crucial role in these processes. Furthermore, Chlorella vulgaris showcased its ability to effectively eliminate nutrient nitrogen, reaching a removal rate of 90 percent at an optical density of 0.2. Moreover, it demonstrated a phosphate removal rate of 80 percent at an optical density of 0.4.
Environmental Engineering
M. Iqhrammullah; S. Saudah; M. Monalisa; F. Fahrurrozi; S.A. Akbar; S.S. Lubis
Abstract
BACKGROUND AND OBJECTIVES: The presence of heavy metals, specifically cadmium, in the environment poses significant threats to both ecological systems and human health. However, microalgae have shown potential in addressing this issue through their ability to absorb cadmium and produce valuable biomass, ...
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BACKGROUND AND OBJECTIVES: The presence of heavy metals, specifically cadmium, in the environment poses significant threats to both ecological systems and human health. However, microalgae have shown potential in addressing this issue through their ability to absorb cadmium and produce valuable biomass, making them a promising solution for bioremediation. Among the various microalgae species, Chlorella vulgaris stands out as a suitable candidate due to its potential for biodiesel production and its capacity to effectively absorb cadmium. Therefore, the main objective of this study is to assess the toxicity of cadmium on Chlorella vulgaris cells using network meta-analysis as a methodology.METHODS: A comprehensive search was conducted on Scopus, Scilit, Google Scholar, and Web of Science to identify relevant studies published from 1 January 1990 to 16 January 2024. Only studies that reported the cell number of Chlorella vulgaris as a result of cadmium exposure were considered for inclusion. The collected data were then subjected to Bayesian frequentist network meta-analysis, utilizing standardized mean difference and a 95 percent confidence interval as measures of effect size. Additionally, a linear regression analysis was performed to examine the dose-dependent impact of cadmium toxicity.FINDINGS: Dose-dependent toxic effects of cadmium on Chlorella vulgaris were evident (R-square of more than 0.90), particularly at a concentration of 1 part per million, deemed as the maximum tolerable threshold. Prolonged exposure revealed a concentration-dependent reduction in cell viability, suggesting potential lifespan shortening. A comparison of growth stimulants, gibberellic acid and brassinolide (standard means differences of 1.7 and 3.8, respectively), in mitigating cadmium toxicity indicated the latter superior effectiveness in sustaining microalgal survivability. The presence of high nitrogen and low phosphorous levels was found to be significantly associated with a reduction in Chlorella vulgaris cells due to cadmium exposure.CONCLUSION: This research has provided conclusive proof of the harmful effects of cadmium on Chlorella vulgaris through the implementation of Bayesian frequentist network meta-analysis, offering valuable insights for environmental management practices. The findings reveal concentration-dependent effects of cadmium toxicity. The survivability of Chlorella vulgaris is determined by the compositions of macronutrients nitrogen and phosphorous. Comparative analyses highlight the superior protective effect of brassinolide over gibberellic acid in mitigating cadmium toxicity. Overall, the findings highlight the potential of Chlorella vulgaris in both bioremediation of heavy metals and biomass production.
Environmental Engineering
P. Periadnadi; N. Nurmiati; F.W. Siregar; T.W. Edelwis
Abstract
BACKGROUND AND OBJECTIVES: Lipid-degrading bacteria found in processing ponds of palm oil mill effluent are recognized for the capacity to break down lipid using lipase enzyme. Identifying novel strains of these bacteria with high bioremediation potential contributes valuable insights to the sustainable ...
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BACKGROUND AND OBJECTIVES: Lipid-degrading bacteria found in processing ponds of palm oil mill effluent are recognized for the capacity to break down lipid using lipase enzyme. Identifying novel strains of these bacteria with high bioremediation potential contributes valuable insights to the sustainable management of palm oil mill effluent. Therefore, this study aimed to identify potential bacteria, assess the in vitro lipid-degrading capabilities, characterize the traits, and evaluate lipid degradation activity of potential isolates from palm oil industry wastewater.METHODS: The method used for exploring the potential of lipid-degrading bacteria in palm oil mill effluent entailed a survey comprising various stages including detection of bacteria presence, in vitro assessment of potential indices, characterization, lipid degradation testing, and determination of lipase activity.FINDINGS: The results showed that several bacteria groups were present in palm oil mill effluent, including 50-74 percent lipolytic, 31-90 percent fermentative, 76-83 percent proteolytic, and 51-74 percent cellulolytic. Selected lipid-degrading isolates demonstrated significant in vitro potential, as evidenced by high lipolytic and fermentative indices. Isolate Enzymatic 3 had the highest lipolytic index, degradation value (48.72 percent), and lipase activity (0.12 units/milliliter), identified as Bacillus cereus central carbon metabolism 2010. Similarly, isolate Fermentative 2 was found to have the highest fermentative index, degradation value (22.35 percent), and lipase activity (0.01 units/milliliter), identified as Bacillus thuringiensis American type culture collection 10792.CONCLUSION: Based on the results, isolates Enzymatic 3 and Fermentative 2 showed promising potential as biological agents for bioremediation of palm oil mill effluent. The results underscored the promising potential of specific bacteria isolates in mitigating lipid-rich effluents, advocating for the integration into sustainable wastewater management practices in palm oil industry. This study provided valuable insights for future investigations aimed at unraveling the intricate mechanisms governing lipid degradation and fostering environmentally friendly solutions for industrial waste management.
Environmental Engineering
E. Riani; N.A. Butet; M. Ansori; M.R. Cordova
Abstract
BACKGROUND AND OBJECTIVES: Cinangka Village in Bogor Regency is a traditional used battery recycling center in West Java, Indonesia. The smelting process was operated in open space, but because of adverse impacts, it has ceased since 2010. This activity generated a large amount of solid waste, categorized ...
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BACKGROUND AND OBJECTIVES: Cinangka Village in Bogor Regency is a traditional used battery recycling center in West Java, Indonesia. The smelting process was operated in open space, but because of adverse impacts, it has ceased since 2010. This activity generated a large amount of solid waste, categorized as hazardous and toxic materials, thereby polluting the air, land, and water. Because an area of Cinangka Village has been converted into a fishing pond, it is necessary to investigate whether the fish that live in this pond are accumulating heavy metals, thereby threatening and harming humans as consumers. This research is important for the innovative remediation of land contaminated with used battery smelting waste.METHODS: Analysis of lead, zinc, arsenic, and iron levels in water, sediment, fish, and aquatic plants, as well as histomorphology analysis of several fish organs, was performed. The safety aspect of consuming fish originating from this location was also calculated. For the used battery recycling area, lead and iron contaminate the environment in the highest concentrations, while arsenic and zinc are always detected but in low concentrations.FINDINGS: The results showed that sediment and water around the pond, previously a burning area of used battery smelting but 12 years after cessation, are polluted by heavy metals, not only lead, zinc, arsenic, and iron. Other metals are present because lead and lead oxide plates are impure and associated with other minerals. According to the lead concentration, the soil/sediment is still categorized as hazardous and toxic material and becomes a pollutant for the ecosystem. Water hyacinth plants that live in ponds are densely cultivated and contaminated with heavy metals. They can become heavy metal phytoremediators on the land where traditional used battery burning was performed. Goldfish from this area are contaminated with high levels of heavy metals and are unfortunately unsafe for consumption because zinc is perilous. Adults are only allowed 3 grams per week, while children may not consume goldfish from this fishing pond. Contaminating heavy metals also cause various damage to fish organs, namely, edema in the kidneys, melano-macrophage centers in the spleen and liver, edema and hyperplasia in the epithelial gills, and fatty degeneration in the liver and its lysed ovary cells.CONCLUSION: Consequently, land in Cinangka Village is still categorized as hazardous, and toxic waste and should not be converted into a fishing pond because the soil is a point source of pollution that contaminates fish with high concentrations of heavy metals and damages their organs. Consuming these goldfish will harm health and thus is prohibited for children. Cleaning and remediation of the environment is necessary and must cover the entire area. Meanwhile, water hyacinth plants can be used as phytoremediators in freshwater ponds to reduce heavy metals
Environmental Engineering
R. Abdallat; A.N. Bdour; A. Abu Haifa; F.F. Al-Rawash; L. Almakhadmeh; S. Hazaimeh
Abstract
BACKGROUND AND OBJECTIVES: Jordan's limited water resources have reduced daily water consumption, leading to a highly concentrated greywater production rate of 54 million cubic meters per year. The presence of nitrate ions, total dissolved solids, total suspended solids, chemical oxygen demand, and biological ...
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BACKGROUND AND OBJECTIVES: Jordan's limited water resources have reduced daily water consumption, leading to a highly concentrated greywater production rate of 54 million cubic meters per year. The presence of nitrate ions, total dissolved solids, total suspended solids, chemical oxygen demand, and biological oxygen demand in greywater poses excellent environmental and health risks when disposed untreated. Water scarcity directly impacts water and food security and is expected to intensify at the current resources management practices. The significance of the current and predictable water shortage in the context of sustainable development and the presence of new technologies brought further attention to utilizing non-conventional water sources. Reclamation of treated wastewater, greywater, brackish, and seawater desalination is Jordan's water budget's only non-conventional water resource. This study aims to address Jordan's water scarcity crisis by developing a low-energy, solar-powered greywater filtration system using natural materials while ensuring compliance with Jordanian standards for safe agricultural applications.METHODS: Several treatment methods have been proposed; however, most of these systems require high to medium energy levels for treatment purposes. Hence, the running cost of the system is relatively high. To address this issue, a four-stage, low-energy, green, and decentralized solar filtration system for greywater treatment has been developed, which uses natural materials available in Jordan and activated carbon to reduce organic and solids content and remove pathogens. The system also uses hot water generated by a Photovoltaic solar system to sanitize the greywater, a novel concept of approach for sanitization. This innovative system is powered entirely by solar energy and can be installed in individual homes.FINDINGS: The results of the developed solar filtration system were very efficient in reducing turbidity, chemical oxygen demand, and Escherichia coli removal: 92, 95, and 100 percent, respectively. Furthermore, the system showed a high potential for total coliforms and Escherichia coli inactivation, reaching 4.64 and 3.15 log units, respectively. Product water meets Jordan standards, ensuring safe reuse for irrigation applications. The findings of this study highlight the satisfactory performance of the developed greywater solar filtration setup. The economic feasibility analysis demonstrates that the proposed system is economically viable and financially sound. The system’s reliance on solar energy and the absence of consumables contribute to its sustainability. They are addressing sustainable practices in greywater treatment in addition to water scarcity concerns.CONCLUSION: The treated greywater, obtained through the series of treatment steps, including solar disinfection, successfully met the Jordanian standards for safe reuse. The substantial reduction of Escherichia coli and total coliforms to acceptable levels demonstrates the treatment system's effectiveness in generating pathogen-free greywater, suitable for a wide range of applications. The study concludes that the solar filtration setup consistently delivers high-quality, pathogen-free greywater, meeting stringent regulatory requirements. This innovative, sustainable system offers a viable solution to Jordan’s water scarcity, introducing a new non-conventional water resource that requires no consumables (non-chemical, non-hazardous materials), thereby addressing sustainability concerns in greywater treatment.
Environmental Engineering
M. Mambwe; K.K. Kalebaila; T. Johnson
Abstract
BACKGROUND AND OBJECTIVES: With technological advances, mining industries use more crude oil and its products. Finding fast, effective, and eco-friendly repair techniques for oil-contaminated soil is crucial. Clay–titanium dioxide/manganese was used to investigate how oil breaks down in soil under ...
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BACKGROUND AND OBJECTIVES: With technological advances, mining industries use more crude oil and its products. Finding fast, effective, and eco-friendly repair techniques for oil-contaminated soil is crucial. Clay–titanium dioxide/manganese was used to investigate how oil breaks down in soil under sunlight. Various soil remediation techniques have been used to discard oil pollutants in soil. A polluted site must be cleaned effectively with a suitable method. Natural attenuation takes too long to produce positive results, whereas landfarming can produce toxic intermediates due to the organisms’ inability to degrade other oil components. Photochemical oxidation is a promising eco-friendly technique that can be employed as an alternative remediation method. The speed at which natural attenuation, photochemical oxidation, and landfarming could remove oil from contaminated soils was examined. Photochemical oxidation’s superiority as a remediation technique over landfarming is hypothesized.METHODS: Using clay modified with titanium dioxide and manganese, the effectiveness of landfarming and photochemical oxidation on oil-contaminated soil was investigated, together with the processes’ kinetics. To establish the processes’ effectiveness and kinetics, the oil residue was calculated at 7-day intervals for 35 days.FINDINGS: Initial oil concentration was 56.6 milligrams per kilogram, and degradation rates ranged from 23.91-80.47 percent. Highest oil reduction was 10.86 milligrams per kilogram. Combined remediation (biocarb and grafted clays) produced high degradation rate constants, k (0.046-0.049/day) and low degradation half-lives, t½ (15.2, 17.4 days). Photochemical oxidation rate constants ranged from 0.015-0.03984/day and half-lives ranged from 17.395-44.971 days, whereas landfarming had a rate constant of 0.008 and half-life of 83.094. Natural attenuation had the lowest k (0.007) and longest half-life (t½) of 94.8 days. Significant differences in means were observed among treatments (control, biocarb, and bicarb + grafted clays) at p ≤ 0.05, suggesting that treatment caused oil decrease in microcosms for biocarb + grafted clays. Grafted clays plus biocarb show potential for combined remediation of oil-contaminated soil.CONCLUSION: One primary indicator used to assess treatments’ efficacy is oil reduction, calculated using difference in oil content in soil before and after remediation. This shows that oil can be quickly removed from oil-contaminated soil by using biocarb + grafted South Luangwa with 80 percent oil reduction. Results suggest that photochemical oxidation may be used to effectively degrade oil and shorten remediation time. Photochemical oxidation is environmentally friendly and degrades oil faster than landfarming. Zambia’s Mopani Copper Mines can consider adopting photochemical oxidation as a remediation technique in treating oil-contaminated soil.
Environmental Engineering
. Rinawati; A. Rahmawati; D.R. Muthia; M.D. Imelda; F.H. Latief; S. Mohamad; A.A. Kiswandono
Abstract
BACKGROUND AND OBJECTIVES: Preliminary studies on the exploration of carbonaceous materials from agricultural waste and their use as adsorbents for antibiotic removal have shown the potential to address a new threat to human health due to antibiotic residue. Therefore, this study developed and synthesized ...
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BACKGROUND AND OBJECTIVES: Preliminary studies on the exploration of carbonaceous materials from agricultural waste and their use as adsorbents for antibiotic removal have shown the potential to address a new threat to human health due to antibiotic residue. Therefore, this study developed and synthesized graphene oxide from corn cob for its efficiency in removing ceftriaxone and ciprofloxacin.METHODS: The Hummers methods were used to synthesize graphene oxide from corn cobs. Graphene oxide was characterized using Fourier transform infrared, scanning electron microscope-energy dispersive x-ray, and x-ray diffraction instruments. During the synthesis process, antibiotic adsorption tests were extensively conducted by exploring four variables, namely dosage of adsorbent, potential hydrogen, concentration, and contact time.FINDINGS: The result showed that graphene oxide from corn cob effectively removed 47 percent of ceftriaxone and 92.62 percent of ciprofloxacin. Furthermore, to ensure optimum use of the adsorbents, antibiotics ceftriaxone and ciprofloxacin weighing 40 milligrams and 20 milligrams. This is in addition to the initial concentrations of 14 and 2 parts per million, the potential of hydrogen 4, and contact times of 50 and 40 minutes, respectively.CONCLUSION: In conclusion, adsorbents made from corn cobs are better at the removal of ciprofloxacin from water than the antibiotic ceftriaxone. The difference in molecular structure affected the percentage of antibiotic adsorption onto graphene oxide derived from corn cob. This study underscores the potential of the derived material as a promising adsorbent for efficiently removing ciprofloxacin from aquatic environments. The use of agricultural waste as advanced materials to address antibiotic residue pollution provided additional environmental pollution.
Environmental Engineering
D. Utari; N.I. Hawa; G. Fizumli; H. Agustina
Abstract
BACKGROUND AND OBJECTIVES: Plastic pollution is increasing globally along with the growing consumption patterns of the global community, leading to practicality (social behavior). The primary contributors to pollution are single-use plastic (SUP) items and inadequate waste management techniques. This ...
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BACKGROUND AND OBJECTIVES: Plastic pollution is increasing globally along with the growing consumption patterns of the global community, leading to practicality (social behavior). The primary contributors to pollution are single-use plastic (SUP) items and inadequate waste management techniques. This research attempts to examine local communities’ determinants and behavioral patterns regarding plastic waste management.METHODS: This cross-sectional analytical study includes 195 respondents and conducted at Antang Lake, Makassar. The social sciences statistical package version 26 was used to perform chi-square tests and multiple regression analysis to examine the main elements influencing individual behavior toward plastic waste management. A survey instrument was provided to participants for data collection.FINDINGS: The chi-square test results show that the knowledge variable has a statistically significant relationship with plastic waste management behavior at home, with a test statistical value of 0.002. Respondents with limited knowledge are 2.603 times more likely to have poor household plastic waste management behavior than those with substantial knowledge. The knowledge variable is also significantly related to household plastic waste management behavior simultaneously with a statistical test value of 0.000, showing a strong relationship. This variable influences 11.8 percent of the behavior in question. Attitude and action variables do not have a significant relationship partially or simultaneously with household plastic waste management behavior.CONCLUSION: Increased plastic consumption has led to microplastic pollution, environmental damage, and deteriorating health conditions. Thus, intervention is required to improve optimal waste management behavior in the community. Increasing awareness about environmental management and educating the public on the impact of microplastics on family health can contribute to enhanced knowledge awareness. This research aims encourage greater awareness of environmental condition to minimize toxicity resulting from the negative impacts of plastic waste.
Environmental Engineering
N. Emalya; Y. Yunardi; E. Munawar; S. Suhendrayatna; T. Tarmizi
Abstract
BACKGROUND AND OBJECTIVES: The utilization of stabilization pond system for landfill leachate treatment is hindered by its requirement for expansive land areas and extended retention periods. Although the system effectively removes organic compounds, its ability to eliminate nutrients such as nitrogen ...
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BACKGROUND AND OBJECTIVES: The utilization of stabilization pond system for landfill leachate treatment is hindered by its requirement for expansive land areas and extended retention periods. Although the system effectively removes organic compounds, its ability to eliminate nutrients such as nitrogen and phosphorus is comparatively limited. Consequently, the leachate subjected to treatment often falls short of meeting the mandated standards for effluent quality. In response to this challenge, a research study was undertaken to investigate the potential of utilizing a consortium comprising microalgae and bacteria in the treatment of landfill leachate.METHODS: The microalgae, bacteria, and leachate utilized in this study were sourced from a leachate treatment facility located at the Aceh regional domestic waste management unit in Blang Bintang, Aceh Besar, Indonesia. The two glass photobioreactors were operated batch-wise, where the first was provided with a combination of air and carbon dioxide, and the other was solely exposed to air. The pollutant removal efficacy in the leachate effluent was assessed through the measurements of chemical oxygen demand, ammonia, nitrate, nitrite, and phosphate concentrations. Subsequently, macroscopic identification of microalgae and bacteria species was also conducted.FINDING: Utilizing a consortium of microalgae and bacteria has demonstrated efficacy in treating leachate, resulting in a notable reduction of contaminants within the effluent. The symbiotic association between microalgae and bacteria in the context of leachate waste treatment is evident. The bacteria’s metabolic actions result in carbon dioxide emission, which subsequently serves as a substrate for the photosynthetic activities of the microalgae. The microalgae facilitate the transfer of oxygen, produced through photosynthesis, to the bacteria to support their metabolic processes. Therefore, introducing exogenous carbon dioxide to the consortium yields minimal discernible effects, given that the bacteria adequately fulfill the carbon dioxide requirements of the microalgae. This discovery enhances the efficacy of leachate treatment techniques by leveraging the utilization of pre-existing mixed cultures of microalgae and bacteria found in leachate facilities.CONCLUSION: This study evaluated the microalgae-bacteria consortium’s effectiveness in reducing leachate pollutants. The consortium exhibited a significant capability, achieving a 75 percent reduction in chemical oxygen demand and successfully eliminating a range of contaminants. Additionally, it demonstrated effective removal of nitrogen compounds such as ammonia, nitrate, and nitrite, with removal rates reaching 75 percent. Notably, the consortium showed a 99 percent removal rate for phosphate compounds. Even with the introduction of carbon dioxide, the pollutant removal remained consistently high, suggesting that the addition of carbon dioxide did not significantly influence the overall process.
Environmental Engineering
O. Setiawan; H.Y.S.H. Nugroho; N. Wahyuningrum; D. Auliyani; K.S. Hardjo
Abstract
BACKGROUND AND OBJECTIVES: Micro-hydropower plants are significant contributors of electricity and clean source of renewable energy. A nationwide or large watershed inventory of potential micro hydropower dam sites is lacking, hindering micro-hydropower development. Traditional ground survey approaches ...
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BACKGROUND AND OBJECTIVES: Micro-hydropower plants are significant contributors of electricity and clean source of renewable energy. A nationwide or large watershed inventory of potential micro hydropower dam sites is lacking, hindering micro-hydropower development. Traditional ground survey approaches for locating micro-hydropower dam sites are expensive, time-consuming, laborious, and vulnerable to inconsistency. Geographic information system frameworks are commonly used, and they provide significant value to hydropower evaluation. A suitability approach for dam site identification is important in supporting the optimization of hydropower utilization in the context of watershed management and in eliminating the inconsistency of conventional approaches. The objective of this study was to identify potential sites for micro-hydropower dams on the basis of various parameters by using a suitability modeling approach based on geographic information system.METHODS: The Saddang Watershed was chosen as the study area, it is located in the South Sulawesi and West Sulawesi Provinces of Indonesia, and it is an example of a large watershed. The analytical hierarchy process was used for criterion weighting and to create a dam suitability index map based on the following criteria: geomorphometry, geology, rainfall, soil texture, and land use land cover. The developed dam suitability index map was validated by comparing it with existing dams by using the receiver operating characteristic curve. The identification of potential micro-hydropower dam sites involved overlay and query methods. It considers dam suitability index, proximity from road and settlement, existence of conservation forest, and the potential hydraulic head.FINDINGS: The dam suitability index map with five suitability classes was obtained, with the high and very high suitability indexes extending to 8.7 percent of the study area. These classes were typified by high drainage density, topographic wetness index, stream power index, low vegetation cover, moderate slope, situated on second or higher stream orders, normal temporal distribution of rainfall, and sandy clay loam soil texture with igneous and sedimentary complex rocks. The developed suitability model was sufficiently effective in determining dam suitability index, as indicated by a value greater than 0.9 of the area under the curve. A total of 635 potential dam locations were identified with high and very high suitability indexes, located on first or second stream orders, within a 4,000 m radius of roads and settlements, outside conservation forest areas, and with a potential hydraulic head greater than 20 meter.CONCLUSION: Integrating a dam suitability index map and restriction factors into a geographic information system framework, enabled a robust analysis for identifying potential sites of micro-hydropower dams. The proposed approach is expected to contribute to the advancement of renewable energy initiatives and water resource management within large watersheds. It is also expected to serve as a valuable resource for policymakers involved in the implementation of micro-hydropower projects and watershed management to support the achievement of renewable energy development targets.
Environmental Engineering
E.S. Siregar; S.U. Sentosa; A. Satrianto
Abstract
BACKGROUND AND OBJECTIVES: This study aims to examine the endogenous variable, low-carbon development, and valuate its influencing factors, given its pivotal role in environmental protection amid climate change concerns and economic growth. Low carbon development is a new platform to maintain economic ...
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BACKGROUND AND OBJECTIVES: This study aims to examine the endogenous variable, low-carbon development, and valuate its influencing factors, given its pivotal role in environmental protection amid climate change concerns and economic growth. Low carbon development is a new platform to maintain economic growth through reducing carbon emissions and reducing the use of natural resources, because it was predicted that reducing emissions will increase economic growth while preventing forest loss, improving air quality and living standards, and reducing mortality rates.METHODS: Utilizing a quantitative method, this study integrates a novel viewpoint by combining low-carbon development with related emission factors. The study utilizes secondary data, specifically time series data spanning 31 years from 1991 to 2021, which were analyzed using regression study methods. The factors being examined include capital formation, deforestation, land transportation, agricultural land, and industrialization.FINDINGS: Findings reveal that low-carbon development in North Sumatra is influenced significantly by capital formation, deforestation, agricultural land, and industrialization, with land transportation showing no substantial impact. Capital formation has a favorable impact on low-carbon development. But, deforestation, land transportation, agricultural land and industrialization have a negative impact on low-carbon development. Together, these determinants account for 77.55 percent of the variance. Capital formation contributes 19.8 percent, deforestation 15.6 percent, agricultural land 19.0 percent, and industrialization 18.9 percent to low-carbon development.CONCLUSION: The hypothesis established in this study is accepted. To foster low-carbon development in North Sumatra, specific attention is required from local governments. Capital formation is vital. Measures include controlling interest rates, supporting businesses, fostering an investment-friendly climate, ensuring security, and integrating environmental sustainability considerations into project implementation to curb carbon emissions. Prevention of deforestation involves tightening land clearance licenses and enhancing institutional quality through environmental protection and property rights legislation. The government must strive for promoting eco-friendly agricultural practices with mitigated through outreach programs involving experts who educate farmers on minimizing emissions, reducing carbon emissions from pesticide with using biochar sourced from empty palm fruit bunches and also rice straw which is very easy to obtain at a low cost and is environmentally friendly, and emphasizing environmental preservation policies in the industrial sector like industrial transformation efforts with an effective approach to reducing carbon emissions such as restructuring various aspects of industrial activities, including investment, final demand, intensity and production methods. The implementation of tax emissions and strategic interventions increases the likelihood of realizing low-carbon development in North Sumatra, aligning with sustainable development goals.
Environmental Engineering
F.A. Febria; A. Syafrita; A. Putra; H. Hidayat; C. Febrion
Abstract
BACKGROUND AND OBJECTIVES: Low-density polyethylene is one of the dominant recalcitrant plastic pollutants in the ocean, thus causing complicated problems. Biodegradation is an efficient, environmentally friendly, and sustainable option to overcome these problems. This study aims to quantitatively and ...
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BACKGROUND AND OBJECTIVES: Low-density polyethylene is one of the dominant recalcitrant plastic pollutants in the ocean, thus causing complicated problems. Biodegradation is an efficient, environmentally friendly, and sustainable option to overcome these problems. This study aims to quantitatively and qualitatively analyze the ability of marine bacterial isolates to degrade low-density polyethylene plastic.METHODS: Bacteria were isolated from plastic samples using serial dilution technique and inoculated on media containing low-density polyethylene powder. Bacterial degradation ability was analyzed quantitatively based on weight loss percentage and energy-dispersive X-ray spectroscopy values, as well as qualitatively based on changes in physical and chemical structures using Scanning Electron Microscopy and Fourier transform infrared spectroscopy. Meanwhile, bacterial isolates were identified based on gene sequence and phylogenetic analyses.FINDINGS: Four bacterial isolates were isolated from low-density polyethylene plastic samples. Quantitative analysis found that the low-density polyethylene film experienced weight loss up to 10-15 percent during 35 days of incubation, with a maximum daily weight loss rate of 0.004 milligrams per day, meaning that the four bacterial isolates have the potential to degrade plastic. Meanwhile, qualitative analysis based on Scanning Electron Microscope observations revealed changes in the physical structure of the film surface in the form of a rough surface, formation of holes, and breakdown into clumps across the film surface. Variations in these changes were tested. In the control, no changes occurred and the film surface remained flat and smooth. Conversely, the results of the energy dispersive X-ray spectroscopy spectrum analysis showed that the low-density polyethylene film broke down into smaller fragments, characterized by a decrease in mass from 98.51 percent to 98.23 percent. Fourier transform infrared observations showed variations in transmittance and wavenumbers, indicating changes in chemical bonds or functional groups in the low-density polyethylene film which caused it to become brittle and break down into smaller fragments with a lower molecular weight, making it easier for bacteria to digest. The results of the gene sequence analysis identified four bacterial isolates, namely Lysinibacillus sp. IBP-1, Bacillus sp. IBP-2, Bacillus paramycoides IBP-3, and Bacillus cereus IBP-4. Based on the quantitative and qualitative analyses, the ability of the bacterial isolates to degrade low-density polyethylene film was shown in the following order: Bacillus paramycoides IBP-3 > Bacillus cereus IBP-4 > Lysinibacillus sp. IBP-1 > Bacillus sp. IBP-2.CONCLUSION: All four marine bacterial isolates can use low-density polyethylene as the sole carbon source. Based on quantitative and qualitative analyses, Bacillus paramycoides IBP-3 has the best potential for degrading low-density polyethylene film. This study provides information on potential bacterial isolates that can be developed to control low-density polyethylene plastic waste.
Environmental Engineering
M.K. Rosyidy; E. Frimawaty
Abstract
BACKGROUND AND OBJECTIVES: Oil palm is one of the crops that has an essential role in Indonesia's engineering field. This condition has led to oil palm plantation intensification, which has been extensive to deforestation in Indonesia, including Jambi province. The main aim of this investigation is to ...
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BACKGROUND AND OBJECTIVES: Oil palm is one of the crops that has an essential role in Indonesia's engineering field. This condition has led to oil palm plantation intensification, which has been extensive to deforestation in Indonesia, including Jambi province. The main aim of this investigation is to evaluate deforestation and land change affected by oil palm expansion conducted by smallholders, which influences environmental change using remote sensing combined with a geographic information system approach. This study utilizes the change of oil Palm in spatial-temporal (spatial and temporal) in Jambi province related to land change and environmental impacts.METHODS: This research uses data from Landsat 8 satellite imagery. The land cover classification was done using the Maximum Likelihood approach, while the overlay method was used for land change analysis. Accuracy assessment of classification results uses a confusion matrix taking into account overall accuracy and Kappa Hat. Within the field observation, the validation class is the oil palm class, using documentation and plotting using the global positioning system, and other classes are validated using the Region of Interest collected through Google Earth. This research uses Aviation Reconnaissance Coverage Geographic Information System 10.1 software to transform the categorization results into vector data. FINDINGS: This study shows that the landcover classification results have high accuracy. This study shows that the area of oil palm land from 2015 to 2019 has increased along with a decrease in land used, such as forests and others. The area of oil palm land 2014 was 2,071,345 hectares, while the area in 2019 was 2,110,545 hectares. In other words, there was an increase in land cover due to land clearing and deforestation, namely 39.2 thousand hectares. The built-up area has also increased in the last five years, namely 165,358 hectares. The number of oil palm plantations tends to be greater in relatively plain areas compared to areas with relatively high altitudes and steep slopes. Small farmers'''' area of oil palm land increased by 1,000 hectares in 2014-2018. The most significant increase occurred in 2016-2017, around 38,889 hectares.CONCLUSION: This study demonstrates that using Landsat 8 imagery combined with GIS approaches provides the optimal method for an in-depth analysis of land cover changes related to oil palm expansion and land clearing that occur on a broader spatial scale and temporal in Jambi Province. This study shows that smallholder oil palm plantations in the Jambi region play an important role in increasing deforestation in Jambi Province, especially in Indonesia. This study is expected to serve as a valuable resource for informing policy decisions aimed at addressing the issue of deforestation resulting from the prospective increase of oil palm crops in the forthcoming period.
Environmental Engineering
D.S.I. Sondakh; F.R. Tulungen; J.K. Kampilong; F.S.J. Rumondor; Y.S. Kawuwung; E.P. Sanggelorang
Abstract
BACKGROUND AND OBJECTIVES: Anthropogenic activities in livestock sectors are responsible for emitting substantial amounts of greenhouse gases, including carbon dioxide, methane, and dinitrous oxide, into the atmosphere, thereby contributing to climate change. The impact of these gases can be reduced ...
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BACKGROUND AND OBJECTIVES: Anthropogenic activities in livestock sectors are responsible for emitting substantial amounts of greenhouse gases, including carbon dioxide, methane, and dinitrous oxide, into the atmosphere, thereby contributing to climate change. The impact of these gases can be reduced through effective mitigation and adaptation efforts. This study aimed to estimate the livestock greenhouse gas emissions in Minahasa District, Indonesia; identify the greenhouse gas sources and distribution; and provide feasible mitigation options.METHODS: This study used mixed methods to collect primary and secondary data from breeders and stakeholders in the Minahasa Regency. Interviews and questionnaires were also conducted, and the local government office provided secondary data. Breeders from various groups who lived in 25 different districts participated in this study, and the data analysis techniques used a Tier 1 model to process the data. The participants were included in focus group discussion activities for qualitative data collection to formulate potential mitigation strategies.FINDINGS: The livestock sector emitted 48.83 gigagrams of carbon dioxide equivalent in 2021, and this was expected to increase by 24.98 percent in 2022, resulting in a total emission of 65.09 gigagrams of carbon dioxide equivalent. The sector also experienced a steady rise in emissions since 2010, with an average annual increase of 3.17 percent. The emissions were primarily composed of methane and dinitrous oxide, which accounted for 64.68 and 0.41 gigagrams carbon dioxide equivalent, respectively. In terms of livestock greenhouse gas distribution, the Sonder District produced 13.98 percent of the emission at 8.77 gigagrams of carbon dioxide equivalent. The main emissions resulted from methane manure management and enteric fermentation at 84.53 and 15.23 percent (7.41 and 1.34 gigagrams of carbon dioxide equivalent, respectively), while the remaining was composed of dinitrous oxide gas. In Kawangkoan District, the greenhouse gas emissions were dominated by methane from enteric fermentation and manure management, which accounted for 15.23 and 20.05 percent (5.63 and 1.43 gigagrams of carbon dioxide equivalent). In addition, the total emission accounted for 11.33 percent at 7.11 gigagrams of carbon dioxide equivalent.CONCLUSION: The study produced an estimate of greenhouse gases from the livestock sector in the Minahasa Regency. During the studied period (2010-2022), the total greenhouse gas emissions exhibited an average annual increase of 3.17 percent. In 2022, the emissions consisted of methane and dinitrous oxide, with respective contributions of 99.38 percent per year and 0.62. Based on the spatial mapping, the Sonder District produced the largest cumulative emissions, primarily driven by emissions from animal waste management. Conversely, the Kawangkoan District dominated emissions stemming from the enteric fermentation of ruminant animals. These findings imply that all stakeholders in the Minahasa Regency should prioritize efforts to implement adaptation and mitigation programs to reduce these impacts.
Environmental Engineering
L. Agustina; M. Romli; P. Suryadarma; S. Suprihatin
Abstract
BACKGROUND AND OBJECTIVES: To improve photocatalytic degradation perfomance, photocatalyst particles with a larger surface area preferred. The effectiveness of titanium dioxide as a photocatalyst depends on the synthesis method used. The method affect the particle size, crystallinity and phase composition ...
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BACKGROUND AND OBJECTIVES: To improve photocatalytic degradation perfomance, photocatalyst particles with a larger surface area preferred. The effectiveness of titanium dioxide as a photocatalyst depends on the synthesis method used. The method affect the particle size, crystallinity and phase composition of the produced catalyst. This study aims to develop a green synthesis process of nano- titanium dioxide photocatalysts for the advanced treatment of palm oil mill effluent.METHODS: The green synthesis of titanium dioxide nanoparticles used de Man-Rogosa-Sharpe broth media containing Lactobacillus bulgaricus culture and titanium oxyhydroxide metal oxide. The factors investigated were the molarity of titanium oxyhydroxide (0.025 molar; 0.035 molar and 0.045 molar) and temperature (40; 50 and 60 degrees Celsius). The synthesized photocatalyst was characterized using a particle size analyzer to determine the particle size. The produced photocatalyst with a nanoparticle size range of 1-100 nanometer was further characterized using scanning electron microscopy-energy dispersive X-ray and X-ray diffraction. The photocatalyst was tested for advanced treatment of palm oil mill secondary effluent. The factors investigated in this test included the irradiation time and titanium dioxide photocatalyst dosage. The treatment performance was evaluated in terms of effluent quality and pollutant elimination efficiency.FINDINGS: Nano titanium dioxide photocatalysts have been synthesized through titanium oxyhydroxide metal oxide biologically using Lactobacillus bulgaricus. The synthesis process at a temperature of 60 degrees Celsius and a 0.025 molar metal oxide solution produced a titanium dioxide photocatalyst with a size of 33.28 nanometer. The content of titanium and oxygen constituents in the photocatalyst was confirmed to be 39.06 percent and 47.95 percent respectively, with 67.6 percent titanium dioxide crystallinity in a theta degree of 25.4. This indicates that the green synthesis has produced an anatase diffraction nano titanium dioxide photocatalyst. Testing the titanium dioxide photocatalyst to treat palm oil mill secondary effluent yielded in elimination efficiency of 16.16-27.27 percent for chemical oxygen demand and 11.05-21.95 percent for biological oxygen demand. Phenol, which is toxic and difficult to degrade biologically, could eliminated significantly (up to 81.12 percent) using a photocatalyst dose of 1 gram per liter at a time irradiation of 2.5 hour.CONCLUSION: The biological synthesis of nano titanium dioxide photocatalysts is affected by temperatures and metal oxide concentrations. The photocatalytic process for advanced treatment of palm oil mill secondary effluent shows that this synthesis process effectively eliminates phenols. Some compounds such as lignin, amino acids, and pectin are not significantly mineralized using this process.
Environmental Engineering
M. Samimi
Abstract
BACKGROUND AND OBJECTIVES: Industrial wastewater usually contains metal ions which are hazardous to human and aquatic organisms. Nowadays, the application of inexpensive biomaterials in adsorptive removal of metal ions, such as plant biomass, has been widely considered. In this study, the efficiency ...
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BACKGROUND AND OBJECTIVES: Industrial wastewater usually contains metal ions which are hazardous to human and aquatic organisms. Nowadays, the application of inexpensive biomaterials in adsorptive removal of metal ions, such as plant biomass, has been widely considered. In this study, the efficiency of Eucalyptus globulus fruit biomass for biological adsorption of cadmium ions from aquatic environments has been evaluated.METHODS: After drying, the collected biosorbent was ground and powdered. The dried biomass, after screening with particle size of less than 45 micrometers, was used in all experiments. The effects of operating factors, such as biosorbent to cadmium ratio, pH value of the solution and residence time of biomass and metal, on the amount of analyte adsorption were evaluated by response surface methodology. The optimum conditions for maximum metal uptake by Eucalyptus globulus fruit biomass were also evaluated using the Box-Behnken Design model. Kinetic studies were statistically described to investigate the metal adsorption process.FINDINGS: Validation experiments showed the accuracy of the model proposed for determining the optimum conditions for the cadmium biosorption process. Based on the experimental data, the values of coefficient of determination, adjusted coefficient and predicted coefficient used in the model were determined as 0.9948, 0.9855 and 0.9245, respectively. Using the model, the maximum cadmium ion adsorption by biomass was obtained at 93.65 percent, biosorbent-to-metal ratio of 9:1, pH value of 6, and contact time of 80 minutes.CONCLUSION: In the present study, the Eucalyptus globulus fruit biomass, under optimal operating conditions, proved to be an efficient sorbent for cadmium uptake from aqueous environments. The results from the experimental data of the adsorption studies were consistent with pseudo-second-order kinetics (maximum capacity of 128.2 milligram per gram), indicating that the chemical adsorption of cadmium on the used biomass occurring in monolayers.