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
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.
Environmental Engineering
P. Chanpiwat; A. Numprasanthai
Abstract
BACKGROUND AND OBJECTIVES: Cadmium contamination in rice grains with a maximum concentration 19 times the national food standard at sites downstream of zinc mines in Thailand has been reported since 2005. These cultivated rice grains are consumed by local residents and have increased the risk of renal ...
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BACKGROUND AND OBJECTIVES: Cadmium contamination in rice grains with a maximum concentration 19 times the national food standard at sites downstream of zinc mines in Thailand has been reported since 2005. These cultivated rice grains are consumed by local residents and have increased the risk of renal dysfunction in residents. Decreasing negative health effects by reducing cadmium accumulation in rice should be considered. Since the soil characteristics affecting the toxicity and accumulation of cadmium in rice cultivated in cadmium-contaminated soils have never been reported, this study was conducted to investigate the soil characteristics affecting the plant availability and mobility of cadmium in paddy soils and the impacts of these soil characteristics on rice seed germination and accumulation in rice.METHODS: The study area is the Mae Tao Subdistrict, Mae Sot District, Tak Province, located downstream of abandoned zinc mines in northwestern Thailand. A total of 36 paddy fields that were reported to produce rice grain with cadmium contents exceeding the national standard for cadmium in rice (0.4 milligrams per kilogram) were randomly selected for composite soil sample collection. The physicochemical characteristics of the soils, including soil texture, redox potential, cation exchange capacity, potential of hydrogen, organic matter, total cadmium concentration, and chemical speciation and concentration of plant-available cadmium, were analyzed. The toxicity of cadmium to rice and the cadmium accumulation ability in rice were assessed through the germination of Khao Dok Mali 105, a popular rice variety for cultivation and consumption in the study area.FINDINGS: Total cadmium concentrations of 0.20 to 89.87 milligrams/kilogram were found in the soils, with 64 percent of all samples containing values greater than the national background value in agricultural soils. Up to 74.2 percent and 99.5 percent of total cadmium was found in the forms of mobile- and plant-available cadmium, respectively. Plant-available cadmium caused significant reductions in the number of seeds germinated and root length. Cadmium toxicity to rice was positively affected by the concentrations of exchangeable, plant-available and total cadmium. The concentrations of plant-available, exchangeable, carbonate-bound, and total cadmium strongly affected the accumulation of cadmium in germinated roots. Cluster analysis showed that plant-available cadmium was the main factor responsible for high cadmium accumulation in rice.CONCLUSION: Based on the overall analyses of soil characteristics affecting the mobility and plant availability of cadmium in soils and its toxicity and accumulation in germinated rice, the immobilization of plant-available cadmium in soils by adding organic matter-rich amendments to soils is recommended. In addition, oxidizing soil conditions should be maintained during rice cultivation to reduce the phytoavailability of cadmium in soils.
Environmental Engineering
L. Sulistyowati; Y. Yolanda; N. Andareswari
Abstract
BACKGROUND AND OBJECTIVES: The Belawan Harbor is the third largest port, which is located in an estuary, causing the port water area to be vulnerable to pollution, especially heavy metals. Conflicts between the community and the port authorities often occur due to pollution. Heavy metals are dangerous ...
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BACKGROUND AND OBJECTIVES: The Belawan Harbor is the third largest port, which is located in an estuary, causing the port water area to be vulnerable to pollution, especially heavy metals. Conflicts between the community and the port authorities often occur due to pollution. Heavy metals are dangerous contaminants for waters, and total organic carbon in waters is needed but will cause eutrophication if the concentration is excessive in the environment. The level of heavy metal pollution in the waters of the Belawan Harbor and the factors that cause the pollution should be analyzed, because the level of heavy metal pollution has not been measured in the sediments of harbor waters. This study can be used as a reference for the actions of related agencies in dealing with heavy metal pollution in waters.METHODS: Sampling of sediments was performed at 10 locations, starting before the harbor activity began and moving toward the open sea. Sampling was conducted using Van Veen grab. Heavy metal concentrations were analyzed in the laboratory using the atomic absorption spectrometer method to assess the essential heavy metal copper and non-essential heavy metal lead, cadmium, and mercury. Heavy metal pollution in sediments was assessed by analyzing sediment pollution index. The multivariate statistical analysis on the relationship among factors was conducted using Pearson correlation matrix method, principal component analysis, and cluster analysis.FINDINGS: The environmental quality standards used indicate average concentration of heavy metals; lead (28,869 milligram per kilogram) and copper (8,003 milligram per kilogram) are below the quality standard. The mercury concentrations are undetectable (<0.00011 milligram per kilogram) at each station. By comparison, the concentration of cadmium (1,455 milligram per kilogram) exceeded the Interim Sediment Quality Guidelines from the Canadian Council of Ministers of the Environment. Results of the index analysis show that the average value of the pollution factor of copper is −0.177 (low contamination), that of lead is −1.433 (moderate contamination), and that of cadmium is −4.850 (high contamination); the geoaccumulation index value of copper is −5.328. (not polluted), that of lead is −0.190 (unpolluted), and that of cadmium −1.657 (moderately polluted). As mercury concentration in sediments is relatively low, it is not considered when calculating pollution levels. Overall, on the basis of a pollution index of 1.033 (1 < pollution load index ≤ 2), this condition indicates that the waters of the Belawan Harbor are categorized as not polluted to lightly polluted. The highest total organic carbon is at the estuaries of the Belawan and Deli Rivers. The sediment fraction is 72.2 percent sandy, 16.4 percent sludge, and 11.4 percent clay substrate.CONCLUSION: Pollution in the waters of the Belawan Harbor is in the category of not polluted to slightly polluted. Although the pollution is still in the light category, this must be of particular concern to the relevant agencies, especially the local government, to make the right policies to overcome this pollution immediately. Pollution problems increase with the anthropogenic activities around coastal areas, as well as activities in the Belawan and Deli River watersheds, because the pollutant will flow from the upstream to the estuary area.
Environmental Engineering
D.B. Aviantara; F. Suciati; G. Hadiko; N.S. Indrasti; M. Yani
Abstract
BACKGROUND AND OBJECTIVES: Polychlorinated biphenyls are pervasive contaminants that are receiving attention worldwide. Due to their well-known propensity to have harmful impacts on both humans and the environment, polychlorinated biphenyls have been internationally banned for use. In this study, dechlorination ...
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BACKGROUND AND OBJECTIVES: Polychlorinated biphenyls are pervasive contaminants that are receiving attention worldwide. Due to their well-known propensity to have harmful impacts on both humans and the environment, polychlorinated biphenyls have been internationally banned for use. In this study, dechlorination of five polychlorinated biphenyl congeners, 2,2′,5,5′-tetrachlorobiphenyl, 2,2′,4,5,5′-pentachlorobiphenyl, 2,2′,3,4,4′,5′-hexachlorobiphenyl, 2,2′,3,4,4′,5′-hexachlorobiphenyl, 2,2′,4,4′,5,5′-hexachlorobiphenyl, and 2,2′,3,4,4′,5,5′-heptachlorobiphenyl, are evaluated. The chlorines from polychlorinated biphenyl congeners were removed using a heterogeneous catalyst synthesized via microwave-assisted impregnation of zinc metal onto pulverized shrimp shell waste.METHODS: The five polychlorinated biphenyl congeners were dechlorinated through treatments combination of time (1–4 hours), heat (150–250 degree celsius), and catalyst proportion (1–5 percent weight/weight basis). The dechlorination trials followed the Box–Behnken experimental design and then analyzed using response surface methodology. Levels of the remaining polychlorinated biphenyl congeners were monitored by using a gas chromatograph equipped with an electron capture detector.FINDINGS: The results of the trials demonstrated that among the five polychlorinated biphenyl congeners, only 2,2′,3,4,4′,5,5′-heptachlorobiphenyl did not respond to the provided treatments. Three congeners, namely, 2,2′,5,5′-tetrachlorobiphenyl, 2,2′,4,5,5′-pentachlorobiphenyl, and 2,2′,4,4′,5,5′-hexachlorobiphenyl, showed positive response, and one congener 2,2′,3,4,4′,5′-hexachlorobiphenyl showed negative response to the provided treatments. These findings suggested that chlorine attached to the para position of the biphenyls ring was easier to remove. The efficiency calculation of total polychlorinated biphenyl concentrations after treatments was approximately 25 percent. Such a low degree of effectiveness may be caused by the catalyst becoming inactive, either chemically through the deposition of chlorines that have been removed from the biphenyl ring or mechanically by the leaching of zinc from the surface of the pulverized shrimp shell due to insufficient mechanical strength. Optimization via response surface methodology produced optimal results for dechlorination at 150 degree celcius for 2.4 hours with 5 percent additional catalyst.CONCLUSION: The total amount of polychlorinated biphenyls that remained after dechlorination was not significantly impacted by the treatment combination of temperature, duration, and weight of the catalyst. However, the treatments had significant effects on the chlorine removal at the para positions of the biphenyl ring. In this case 2,2′,5,5′-tetrachlorobiphenyl, 2,2′,4,5,5′-pentachlorobiphenyl, and 2,2′,4,4′,5,5′-hexachlorobiphenyl congeners have positive responses and 2,2′,3,4,4′,5′-hexachlorobiphenyl congener has a negative response. For polychlorinated biphenyl congeners having more than six chlorines, no chlorine removal was observed.
Environmental Engineering
L. Sulistyowati; N. Andareswari; F. Afrianto; A. Rais; M.F. Hafa; D. Darwiyati; A.L. Ginting
Abstract
BACKGROUND AND OBJECTIVES: The monitoring of the Brantas watershed showed a light-polluted status. This study began by identifying the priority of regional problems using importance-performance analysis. Furthermore, a hydrological analysis was conducted to determine the pollutant area of the Brantas ...
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BACKGROUND AND OBJECTIVES: The monitoring of the Brantas watershed showed a light-polluted status. This study began by identifying the priority of regional problems using importance-performance analysis. Furthermore, a hydrological analysis was conducted to determine the pollutant area of the Brantas watershed by applying terrain analysis. When terrain analysis in hydrology is combined with participatory community information, it can provide valuable insights into water pollution and help prioritize remediation efforts. Integrating local knowledge with scientific data can improve decision-making and increase the effectiveness of water management strategies.METHODS: The methodological approach employed in this study included importance-performance analysis to determine priority problems in Batu City and terrain analysis as a hydrological analysis to determine the pollutant area in the Brantas watershed. The importance-performance analysis assessment data were obtained from 197 respondents representing the occupations of the people of Batu City. The terrain analysis data were derived from the surface elevation data in the form of a digital elevation model.FINDINGS: According to the importance-performance analysis community assessment, urban trash management was one of the crucial yet low-rated features. The terrain analysis results demonstrated that business and industrial activities were distributed in locations with high flow accumulation values, indicating that the water pollution in Batu City was triggered by the presence of business and industrial activities in the watershed accumulation areas. Along the upstream Brantas watershed, 460 business and industrial activities were discovered. Therefore, the results of importance-performance analysis and terrain analysis had a correlation. They were also closely related to the assessment results of the contaminated Brantas watershed.CONCLUSION: The following are some recommendations for the watershed's quality improvement: 1) cooperation among the Government, communities, and the private sector for addressing water pollution issues; 2) the development of environmentally friendly technologies in water treatment; and 3) education and outreach to communities about the importance of preserving water resources. As a city experiencing rapid urban development, environmental degradation constitutes a risk to be borne. Accordingly, Batu City must continue to develop good environmental management for the sake of nature conservation because the urban system is a unit formed by the social economy and ecological environment subsystem.
Environmental Engineering
N.D. Takarina; O.M. Chuan; T.G. Pin; I. Femnisya; A. Fathinah; A.N.B. Ramadhan; R. Hermawan; A. Adiwibowo
Abstract
BACKGROUND AND OBJECTIVES: Tropical coastal ecosystems globally have been affected by land use changes. This condition has caused a discharge of pollutants into the water, affecting marine organisms, including fish. Due to their habitat preferences, fish are prone to elevate heavy metals in their tissue. ...
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BACKGROUND AND OBJECTIVES: Tropical coastal ecosystems globally have been affected by land use changes. This condition has caused a discharge of pollutants into the water, affecting marine organisms, including fish. Due to their habitat preferences, fish are prone to elevate heavy metals in their tissue. Considering fish is consumable, heavy metal levels in fish can lead to health risks. One of the common edible fish in Southeast Asia is Pennahia argentata. Although widely consumed, there is limited information on how land use influences heavy metal levels in various tissues of this species and its health risk. Fish is one of the main food sources in this region, indicating this information’s importance. This study aims to elaborate on and differentiate the heavy metal levels in tissues and land use types, including settlement and mangrove areas on the West Java coast of Indonesia.METHODS: Locations of this study are the Jakarta coast representing anthropogenic influences in the form of settlements and the Subang coast as a site of mangrove covers. This study combined remote sensing and Geographic Information System analysis with heavy metal analysis using inductively coupled plasma and studied heavy metals, including cadmium, copper, and zinc, in fish tissues such as the gill, digestive tract, and muscle. Differences and correlation of heavy metal data in each tissue and location were statistically analyzed using Pearson correlation values (r), Analysis of Variance, and x2-test. The estimated Daily Intake was used to determine the health risk consumption of this species.FINDINGS: All levels of heavy metals are below the World Health Organization’s permissible limits. Zinc is consistently high in all tissues and locations, while cadmium is the lowest. The result shows that the digestive tract consistently has the highest heavy metal levels compared to other tissues in both locations. Heavy metal in muscle has the lowest level. Copper and zinc in the muscles of fish living on the settlement coasts were 62.69% and 37.18% higher (P <0.05) than fish inhabiting mangrove coasts.CONCLUSION: Trace elements in the commercial fish P. argentata were significantly affected by differences in land use. Variations in land use have elevated heavy metal levels in fish tissues. Given the high levels of heavy metals, the digestive tract can be chosen as a specific fish tissue to be used as a bioindicator to monitor cadmium, copper, and zinc, particularly on the West Java coast in Indonesia. Because the Estimated Daily Intake for zinc in Jakarta is high, consuming fish should be done with caution.
Environmental Engineering
A. Mallongi; A.U. Rauf; R.D.P. Astuti; S. Palutturi; H. Ishak
Abstract
BACKGROUND AND OBJECTIVES: The increasing population and anthropogenic activities in coastal areas affects the presence of mercury in coastal waters. Therefore, this study aims to 1) assess the ecological and human health risk of mercury contamination in coastal water; 2) analyze the effectiveness of ...
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BACKGROUND AND OBJECTIVES: The increasing population and anthropogenic activities in coastal areas affects the presence of mercury in coastal waters. Therefore, this study aims to 1) assess the ecological and human health risk of mercury contamination in coastal water; 2) analyze the effectiveness of polymer sulfur as an absorbent for mercury.METHODS: A total of fifteen water samples were obtained from the coastal areas of Makassar and were analyzed using cold vapor atomic absorption spectrophotometry. Ecological and human health risks were assessed using established assessment methods by the United States Environmental Protection Agency. The uncertainty and sensitivity tests for independent variables in human health risk were assessed by the Monte Carlo Simulation method. Furthermore, polymer sulfur was used as a promising technique for capturing and reducing the level of mercury in the water column.FINDINGS: The results showed that the mean concentration of mercury was very high and exceeded the values established by the World Health Organization, United States of Environmental Protection Agency, and Indonesian National Standards, indicating elevated risks to the ecosystem and human health in the future. Additionally, the Monte Carlo simulation model revealed that the non-carcinogenic risk caused by mercury exposure in adults and children was greater than 1 (Total Hazard Index>1), indicating the health adverse effects for both receptors. From the simulation results, the concentration of mercury at 23.3% and exposure time of 21.3 percent were the most influential and dominant factors in non-cancer risk for adults and children, respectively. Therefore, mercury concentration needs to be reduced in coastal areas. The application of polymer sulfur is effective for reducing mercury concentration in water with a percentage reduction range of 39 – 100 percent and p-value of 0.001.CONCLUSION: Mercury contamination of coastal water in Makassar city poses ecological and health risks. The application of polymer sulfur is an effective way for reducing mercury in the water column.
Environmental Engineering
A.S. Patimah; A. Prasetya; S.H.M.B. Santosa
Abstract
BACKGROUND AND OBJECTIVES: The research aimed to evaluate the water quality of the Cangkring River in Tuban Regency, East Java Province, Indonesia, at the segment near the oil and gas fields (Mudi Pad A, B, and C).METHODS: Water samples were collected from January to September 2021 at seven locations ...
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BACKGROUND AND OBJECTIVES: The research aimed to evaluate the water quality of the Cangkring River in Tuban Regency, East Java Province, Indonesia, at the segment near the oil and gas fields (Mudi Pad A, B, and C).METHODS: Water samples were collected from January to September 2021 at seven locations along the river segment and tested ex-situ using six parameters, including physical, chemical, and microbiological. The pollution index formula was used to calculate, determine, and analyze the river water quality status. Samples at three locations were further tested with 13 additional chemical parameters due to potential contamination by other substances as they were located the closest to the production site and office area.FINDINGS: Sample analysis with six parameters showed a pollution index value of 0.558 or within the predefined standard at one location (SW6) and 1.080–2.721 at the other six locations, indicating slight pollution. Another test at three selected locations (i.e., SW1, SW2, and SW7) with 13 additional parameters increased the pollution index to 5.556–6.170 (moderate pollution). This status change was due to the high presence of nitrite and ammonia in the water samples.CONCLUSION: The oil and gas industry near the Cangkring River has strictly complied with the regulations in treating their produced water. However, it still contains a high amount of nitrite and ammonia, moderately polluting the river water. Therefore, it is necessary to regularly test the river water near oil and gas fields to ensure its quality and safety.
Environmental Engineering
M.R. Maulana; S. Saiful; Z.A. Muchlisin
Abstract
BACKGROUND AND OBJECTIVE: The occurrence of plastic waste pollution in waters has become a major issue globally. One of the waters which tend to be polluted with plastic waste such as bags, food wrappers, and unused fishing nets, is the Krueng Aceh River, which is located in the center of Banda Aceh ...
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BACKGROUND AND OBJECTIVE: The occurrence of plastic waste pollution in waters has become a major issue globally. One of the waters which tend to be polluted with plastic waste such as bags, food wrappers, and unused fishing nets, is the Krueng Aceh River, which is located in the center of Banda Aceh city, Indonesia. Microplastics in the rivers potentially contaminate the fish through the food chains, and are then transferred to humans once consumed. The two species of fish that are frequently caught by fishermen in the Krueng Aceh River and consumed by the local people are mullet Mugil cephalus and bagok catfish Hexanematichthys sagor. Both have the potential of being contaminated with microplastics that enter the river. Therefore, this study aims to analyze the status of microplastic pollution in mullet M. cephalus and bagok catfish H. sagor harvested downstream of the Krueng Aceh River, Banda Aceh, Indonesia.METHODS: The fish samples were caught in three locations, namely in the river estuary, residential, and agricultural areas. A total of 50 mullets and 46 bagok catfish were employed for analysis. Microplastics were analyzed in the digestive tract using a microscope, while waste in the carcass was detected using the fourier transform infrared analysis.FINDINGS: In mullet, the highest number of microplastic particles were found in fish samples caught in river estuary (16 particles/fish on average), followed by the sample from residential areas (10 particles/fish on average). Meanwhile, the lowest abundance of microplastic was recorded in sample near agriculture areas (5 particles/gram body weight). In bagok catfish, microplastic abundance in samples from the river estuary and residential areas was almost the same, and it ranged from 7-8 particles/fish. The lowest particle number was in bagok catfish caught in the region near agricultural areas. This study indicated fiber as the most dominant microplastic in the two fish species at all sampling locations. It also had three colors in the alimentary tract of mullet and bagok catfish, namely red, blue, and black, which was predominant. The fourier transform infrared spectrum showed several wavenumber peaks signifying alkane compounds’ presence, which are microplastic characteristics. Based on the peak values, the presence of two polymer types was suspected, namely polyethylene, and polypropylene.CONCLUSION: Fiber and film microplastics were found in the digestive tract of mullet and bagok catfish, where the number of particles was most abundant in the mullet. The fourier transform infrared test was also detected the presence of microplastic pollutants in both species. This indicates that mullet and bagok catfish in Krueng Aceh River have been contaminated by microplastics and are not safe for consumption.
Environmental Engineering
M. Hazbehiean; N. Mokhtarian; A. Hallajisani
Abstract
More than 5.5 trillion cigarettes are manufactured, and approximately 4.5 trillion cigarette butts are being scattered across the globe per year. These cigarette butts are considered as one of the most hazardous wastes and environmental threats in the world. Thermochemical techniques can be used to turn ...
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More than 5.5 trillion cigarettes are manufactured, and approximately 4.5 trillion cigarette butts are being scattered across the globe per year. These cigarette butts are considered as one of the most hazardous wastes and environmental threats in the world. Thermochemical techniques can be used to turn biomass and solid wastes into valuable final products. Pyrolysis is a comfortable thermochemical technique for turning biomass into biochars, biofuels, briquette solid fuels, and further valuable products such as activated carbons, carbon black, and printing ink. In this study, it was attempted to review the available researches about pyrolysis of cigarette butts with an emphasis on transforming them into carbonated solid and liquid products. It was found that, in addition to the process variables, the type of cigarette butts treatment has a significant effect on the yield and quality of the finished goods. Further studies on the pyrolysis of cigarette butts, especially microwave-assisted pyrolysis and hybrid waste pyrolysis, seemed to be necessary. Solving the technical issues associated with the pyrolysis of cigarette butts to produce the value-added goods would contribute to their application in waste disposal and recycling of other resources. Future studies should focus on the separation methods with the help of gas products to provide the heat required in the reactor. Moreover, mixing the sewage sludge material, as a feed, with cigarette butts and application of appropriate models and experiments to attain the products with specific properties are recommended. The results of this study can be used to eliminate the hazards of the cigarette butts scattered in the environment and create the added value for the pyrolysis process.
Environmental Engineering
M. Mambwe; K. K. Kalebaila; T. Johnson
Abstract
Crude oil continues to impact many nations as it is among the major sources of fuel. Its role in making life in modern societies comfortable cannot be overemphasized as it is readily available and easy to use. Contamination resulting from its use in industries such as mining, transportation and ...
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Crude oil continues to impact many nations as it is among the major sources of fuel. Its role in making life in modern societies comfortable cannot be overemphasized as it is readily available and easy to use. Contamination resulting from its use in industries such as mining, transportation and petroleum especially soil contamination cannot be overlooked. Soil pollution resulting from oil contamination can be seen as being among the twenty-first-century vulnerabilities because if not well taken care of the consequences can be devastating. Soil contamination is of interest in most societies because it affects both the environment and humans. This review highlights common sources of soil pollution and their effects, oil waste disposal methods, soil remediation techniques that are well established and those still in their infancy. Such techniques include bioremediation such as phytoremediation and landfarming, where percent removal of contaminated soils was reported from 68% to 89 % in 40 days to 1 year, respectively; physical methods such as excavation and incineration (75-86% removal); chemical methods such as oxidation (48 % by Fenton process); and photocatalysis (67% using titanium dioxide). The choice of remediation in mining, transportation and petroleum industries depends on the urgency and hazardous effects of the pollutant. In Zambia, Mopani Copper Mines uses landfarming as a means to mitigate large amounts of soil contaminated with oil wastes, but the process is slow. In the proposed research, photocatalysis coupled with adsorption of oil on clay will be used to assess the effectiveness of this emerging technology to quicken the degradation of oil in soils. Clay will be incorporated with metal ions and with hydrophobic groups to enhance light absorption and oil-clay interaction, respectively. Photochemical remediation techniques for remediation of soils polluted with oil have attracted considerable interest as the processes are reported to enhance the degradation of oils in soil compared to the biological and physical methods. The extent of photo-degradation of oil waste will be evaluated using the Soxhlet technique by determining the percent residual oil. The importance of remediating contaminated soil in any nation cannot be overemphasized as consequences of not remediating this precious resource might be devastating. Since economic development through industrialization will continue, there is need to constantly improve on methods of mitigating the impact of wastes on the environment, especially in developing countries, where engineering of cheap, nontoxic materials for soil remediation is paramount.
Environmental Engineering
P. Saxena; S. Sonwani
Abstract
The indoor air quality is much more matter of concern as relative to ambient or outdoor air quality, especially in the context of human health. However, very few studies have been reported for remediation of indoor ozone by plant species. The main objective of this study is to evaluate ozone deposition ...
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The indoor air quality is much more matter of concern as relative to ambient or outdoor air quality, especially in the context of human health. However, very few studies have been reported for remediation of indoor ozone by plant species. The main objective of this study is to evaluate ozone deposition velocities and ozone removal effectiveness of three indoor ornamental plant species (Dracaena deremensis, Tagetes erecta and Lilium candidum) that can be used in the remediation of indoor ozone. Ozone deposition velocity was estimated through measurement of leaf surface areas of selected plant species and exposing them to 3-regular daytime cycles where ozone concentrations under controlled conditions first increased from 8 h followed by 16 h in the absence of ozone. Values of ozone deposition velocity after the completion of first exposure were found maximum (7.7 m/h) in case of Dracaena deremensis and minimum (0.5 m/h) after the completion third exposure in Lilium candidum. The ozone removal effectiveness found in the range of 0.7 to 13% for leaf surface area to room volume ratio of 0.06/m with reference to an air exchange system and background loss present in an indoor environment. Among the selected plant species, Dracaena deremensis has got the highest ozone deposition velocity as well as ozone removal effectiveness and Lilium candidum has got the lowest values. Hence, this study concludes with the sustainable use of ornamental plant species in the remediation of the indoor ozone pollution, which can further help in improving the health condition of the residents.
