Document Type : ORIGINAL RESEARCH ARTICLE

Authors

Department of Environmental Engineering, Faculty of Civil Engineering, Babol Noshirvani University of Technology, Babol, Iran

Abstract

BACKGROUND AND OBJECTIVES: Although the characteristics food waste have been well studied, some of the problems associated with result reporting have not been addressed. The related data are usually reported by referring to the global statistics, using the empirical models, and performing the laboratory analysis. The aims of the current study were to analyze the municipal food waste characteristics (including physical, proximate, ultimate and heating value analysis), monitor the differences among the laboratory methods, and highlight the significant differences among the food waste characteristics more accurately.
METHODS: Sampling was performed weekly at a disposal site located in Sari, Mazandaran, Iran. Food waste was extracted from the municipal solid waste samples. Moisture content, pH, organic matter, ash content, organic carbon, carbon to nitrogen ratio, low heating value and chemical equation of the waste were determined and compared by statistical indices.
FINDINGS: The results showed no significant difference between proximate analysis and global statistics for sampling including organic matter and moisture content. In ultimate analysis, statistical investigation of the laboratory results showed that Walkley and black, Kjeldahl, and dry ashing/ion chromatography methods had more accuracy compared to determination by elemental analyzer which puts direct impact on extracted chemical equation. In addition, heating value investigation by empirical models based on proximate analysis (13.6 MJ/kg) was closer to the bomb calorimeter results (13.4 MJ/kg) in average. However, the models developed based on ultimate analysis, including Dulong, Steuer, and Scheurer-Kestner, had a lower accuracy (with higher heating value of 1.4 to 5 MJ/kg). Surveying the reliable sources highlighted the gap in extracted chemical equation and heating value of the food waste with real amount. These findings provided appropriate information about solid waste management and characterization.
CONCLUSION: Investigation of the gap among laboratory methods revealed that determination method was a key factor in accurate characterization of food waste. Thus, without using the most accurate laboratory methods, the implementation of waste management plans would face major problems.

Graphical Abstract

Laboratory analysis to determine the accurate characteristics of urban food waste

Highlights

  • In ultimate analysis of food waste, Walkley and Black, Kjeldahl, and Ion chromatography methods showed higher accuracies compared to determination by elemental analyzer instrument;
  • The weighting fraction of FW in MSW, organic matter, moisture, oxygen and hydrogen contents exhibited a good conformity with the secondary data sources;
  • Investigation of heating value indicated the good conformity of the models developed based on proximate analysis rather than the models developed based on ultimate analysis;
  • The gap between heating value determination by the empirical models based on ultimate analysis and the bomb calorimeter method was significant (about 1.4 to 5 MJ/kg).

Keywords

Main Subjects

Open Access

©2022 The author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit: http://creativecommons.org/licenses/by/4.0/

Publisher’s Note

GJESM Publisher remains neutral with regard to jurisdictional claims in published maps and institutional affliations.

Citation Metrics & Captures

Google Scholar Scopus Web of Science PlumX Metrics Altmetrics Mendeley |

Letters to Editor

GJESM Journal welcomes letters to the editor for the post-publication discussions and corrections which allows debate post publication on its site, through the Letters to Editor. Letters pertaining to manuscript published in GJESM should be sent to the editorial office of GJESM within three months of either online publication or before printed publication, except for critiques of original research. Following points are to be considering before sending the letters (comments) to the editor.

[1] Letters that include statements of statistics, facts, research, or theories should include appropriate references, although more than three are discouraged.
[2] Letters that are personal attacks on an author rather than thoughtful criticism of the author’s ideas will not be considered for publication.
[3] Letters can be no more than 300 words in length.
[4] Letter writers should include a statement at the beginning of the letter stating that it is being submitted either for publication or not.
[5] Anonymous letters will not be considered.
[6] Letter writers must include their city and state of residence or work.
[7] Letters will be edited for clarity and length.

CAPTCHA Image