Assessment of Sewage Sludge Generation, Characteristics, and Potential Treatment Methods in Rapidly Expanding Population Regions
DOI:
https://doi.org/10.14500/aro.12559Keywords:
Anaerobic digestion, Duhok governorate, Sewage sludge management, Sludge characterization, Sludge treatment wetlandsAbstract
This study assesses sewage sludge generation, characterizes its physicochemical properties, and evaluates viable treatment strategies tailored to local conditions. Grab samples were collected from two operating wastewater treatment plants (Shariya and Avro City). Sludge and wastewater were analyzed for total solids, total dissolved and suspended solids, biochemical oxygen demand, chemical oxygen demand (COD), and selected heavy metals. 35 years of climatic data were reviewed, and a socioeconomic survey was conducted. Results indicated substantial current and projected sludge volumes, about 19,895 tons of dry matter for the study area and about 51,268 tons for the governorate per year. The estimated sludge generation rate was 32.9 kg/capita/year. The sludge shows high organic content and extremely elevated COD (for example, Shariya ≈115,800 mg/L). These characteristics indicate significant potential for energy recovery via anaerobic digestion. Chemical analyses revealed localized heavy metal enrichment (notably aluminum and lead in Shariya) that constrains direct land application without pretreatment. Socioeconomically, whereas 90% of respondents reported connections to a water supply, 40% reported insufficiency. Comparison of treatment scenarios indicates that the most viable near-term options for resource recovery and pathogen reduction are low-cost sludge treatment wetlands and mesophilic anaerobic digestion. This study constitutes the first research conducted on sewage sludge management in Duhok City. The results serve as an important database that can be used by policymakers and engineers to develop a sludge management system not only for Duhok but also for other growing Iraqi cities and similar regions.
Downloads
References
Albtoosh, A.F., Alnsour, M.A., and Abu Hajar, H.A., 2023. Sustainable Management of Sewage Sludge in Jordan - as-Samra Wastewater Treatment Plant. A Case Study. [MSc Thesis, ISRA University].
Al-Obaidi, A.R., Al-Anbari, R.H., and Hassan, M.S., 2021. Sewage sludge reuse in concrete industry: A review. IOP Conference Series Earth and Environmental Science, 779(1), p.012010.
Andreoli, C.V., Von Sperling, M., and Fernandes, F., 2007. Sludge Treatment and Disposal, IWA Publishing, London. Appels, L., Lauwers, J., Degrève, J., Helsen, L., Lievens, B., Willems, K., Van Impe, J., and Dewil, R., 2011. Anaerobic digestion in global bio-energy production: Potential and research challenges. Renewable and Sustainable Energy Reviews, 15, pp.4295-4301.
Atilla, B., Yangin-Gomec, C., Altinbas, M., and Ozturk, I., 2003. Anaerobic digestion of municipal sludges with high silt content using granular seed. Journal of Environmental Science and Health Part A, 38(10), pp.2369-2379.
Camargo, F.P., Sérgio Tonello, P., Dos Santos, A.C.A., and Duarte, I.C.S., 2016. Removal of toxic metals from sewage sludge through chemical, physical, and biological treatments-a review. Water Air and Soil Pollution, 227, p.433.
Cao, Y., and Pawłowski, A., 2012. Sewage sludge-to-energy approaches based on anaerobic digestion and pyrolysis: Brief overview and energy efficiency assessment. Renewable and Sustainable Energy Reviews, 16, pp.1657-1665.
Chauhan, P., Rajguru, A.B., Dudhe, M.Y., and Mathur, J., 2020. Efficacy of lead (Pb) phytoextraction of five varieties of Helianthus annuus L. From contaminated soil. Environmental Technology and Innovation, 18, p.100718.
Dawud, K.I., Abdi, S.I., and Umer, M.I., 2024. Assessment of municipal waste water of Duhok district and its usefulness for irrigation. Indonesian Journal of Social and Environmental Issues, 5(2), pp.171-181.
Fericelli, P.D., 2011. Comparison of Sludge Treatment by Gasification vs. Incineration. University of Central Florida, Florida.
Finley, S., Barrington, S., and Lyew, D., 2009. Reuse of domestic greywater for the irrigation of food crops. Water, Air, and Soil Pollution, 199(1-4), pp.235-245.
Garrido-Baserba, M., Molinos-Senante, M., Abelleira-Pereira J.M., FdezGüelfo, L.A., Poch, M., and Hernández-Sancho F., 2015. Selecting sewage sludge treatment alternatives in modern wastewater treatment plants using environmental decision support systems. Journal of Cleaner Production, 107, pp.410-419. Marrone, P.A., 2013.
upercritical water oxidation-current status of full-scale commercial activity for waste destruction. The Journal of Supercritical Fluids, 79, pp.283-288.
McGhee, T.J., and Steel, E.W., 1991. Water Supply and Sewerage. McGrawHill, United States. Mizzouri, N.S., Algabban, M.M.J., and Hassan, H.M., 2017. Assessment of grey water disposal and different treatment options for Domiz camp in Duhok City. Journal of Duhok University, 20, pp.184-195.
Mizzouri, N.S., Kochary, S.A., and Barwari, N., 2022. Decentralized sanitation solutions for temporal internally displaced people (IDPs) and refugees camps and residential complexes in Duhok province-case study. Ain Shams Engineering Journal, 13, p.101706.
Mizzouri, N.S., Kochary, S.A., and Barwari, N., 2020. Decentralized/ semi-centralized sanitation solutions in Duhok governorate-case study. In: 6th International Engineering Conference “Sustainable Technology and Development” (IEC). IEEE, United States, pp.1-6.
Moharir, R.V., Gautam, P., and Kumar, S., 2019. Waste treatment processes/ technologies for energy recovery. In: Current Developments in Biotechnology and Bioengineering. Elsevier, Netherlands, pp.53-77.
Nakhla, S.F., Arafa, A., Naga, I.S., Mohamed, M., Alsherbeny, H.A., Fahmi, N.M., Hosny, H., and Moussa, S., 2022. Primary and secondary sludge treatment using ionizing radiation technology in Alexandria, Egypt. Applied Radiation and Isotopes, 181, p.110101.
Rekani, O.A.O., and Dohuki, M.S.M., 2024. Assessment of filter efficiency in recycling wastewater for irrigation purposes using physicochemical processes in Semel district/Duhok-KR, Iraq. Annals of Forest Research, 67(1), pp.41-54.
Rice, E.W., Bridgewater, L., Association, A.P.H., Association, A.W.W., and Federation, W.E., 2012. Standard Methods for the Examination of Water and Wastewater, American Public Health Association, United States.
Semiyaga, S., Okure, M.A.E., Niwagaba, C.B., Katukiza, A.Y., and Kansiime, F., 2015. Decentralized options for faecal sludge management in urban slum areas of Sub-Saharan Africa: A review of technologies, practices and end-uses. Resources Conservation and Recycling, 104, pp.109-119.
Snyman, H.G., Herselman, J.E., and Tesfamariam, E.H., 2024. The Development of a Framework for the Review of the Sludge Management Guidelines, Water Research Commission, [WRC Report No. 3164/1/24].
Shukri, A.H., Mizzouri, N.S., Saifadeen, A., Saleem, D., and O’Malley, M., 2024. Assessing and improving the sanitation services in Kabarto 2 IDP camp using the smart sanitation approach. Ain Shams Engineering Journal, 15, p.102593.
Suryawanshi, P.C., Chaudhari, A.B., and Kothari, R.M., 2010. Thermophilic anaerobic digestion: The best option for waste treatment. Critical Reviews in Biotechnology, 30, pp.31-40.
ddin, S., Zaman, M., Martínez-Guijarro, K., Al-Murad, M., Behbehani, M., Habibi, N., and Al-Mutairi, A., 2024. Sewage sludge as soil amendment in arid soils - a trace metal, nutrient and trace organics perspective. Emerging Contaminants, 11, p.100420.
Uggetti, E., Ferrer, I., Llorens, E., and García, J., 2010. Sludge treatment wetlands: A review on the state of the art. Bioresource Technology, 101, pp.2905-2912.
United Nations High Commissioner for Refugees (UNHCR)., 2018. Iraq: UNHCR Operational Update. Available from: https://www.unhcr.org/iraq.html [Last accessed on 2025 Jul 15].
Vali, N., Zabihi, S., Shamim, S., Mohsenzadeh, A., and Pettersson, A., 2025. Slow-pyrolysis of municipal sewage sludge: Biochar characteristics and advanced thermodynamics. Biomass Conversion and Biorefinery, 15, pp.21045-21065.
Zeynali, R., Asadi, M., Ankley, P., Mahoney, H., Brinkmann, M., Acharya, B., Mcphedran, K., and Soltan, J., 2025. Smart municipal wastewater treatment sludge management: Enhancement of biogas production from anaerobic digestion amended by optimized sludge-derived biochar. Science of The Total Environment, 989, p.179860.
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2026 Nashwan Sh. Mizzouri
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Authors who choose to publish their work with Aro agree to the following terms:
-
Authors retain the copyright to their work and grant the journal the right of first publication. The work is simultaneously licensed under a Creative Commons Attribution License [CC BY-NC-SA 4.0]. This license allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
-
Authors have the freedom to enter into separate agreements for the non-exclusive distribution of the journal's published version of the work. This includes options such as posting it to an institutional repository or publishing it in a book, as long as proper acknowledgement is given to its initial publication in this journal.
-
Authors are encouraged to share and post their work online, including in institutional repositories or on their personal websites, both prior to and during the submission process. This practice can lead to productive exchanges and increase the visibility and citation of the published work.
By agreeing to these terms, authors acknowledge the importance of open access and the benefits it brings to the scholarly community.
Accepted 2026-07-03
Published 2026-08-24
ARO Journal is a scientific, peer-reviewed, periodical, and diamond OAJ that has no APC or ASC.