Life cycle assessment of wastewater treatment in developing countries: A review

Abstract

Within developing countries, wastewater treatment (WWT) has improved in recent years in but remains a high priority sustainability challenge. Accordingly, life cycle assessment (LCA) studies have recently started to analyse the environmental impacts of WWT technologies on the specific context of less developed countries, mainly in China and India. This work presents a comprehensive review of this knowledge with the aim of critically analysing the main conclusions, gaps and challenges for future WWT-related LCAs in developing countries. The most commonly assessed technologies in the 43 reviewed articles are different variations of activated sludge and extensive treatments applied in decentralized systems; however, studies focused on advanced technologies or new sources of pollution (e.g. micropollutants) are still lacking. Goal and system boundaries are normally clearly defined, but significant stages for some technologies such as the construction and sludge management are frequently not included and functional units should be defined accordingly to specific conditions in developing countries. At the inventory level, a more concise description of sources and technical parameters would greatly improve the quality of the LCAs along with accountability of direct greenhouse gas emissions. Eutrophication and global warming are the two

Assessing environmental impacts of large centralized wastewater treatment plants with combined or separate sewer systems in dry/wet seasons by using LCA

“…In addition, BOD, COD, SS, N and P vary in wide ranges in either developed or developing countries. The strength of wastewater into each WWTP in our study falls well within the pollutant concentration range in developing and developed countries (Gallego-Schmid and Tarpani 2019), respectively, but the strength of wastewater into MWTW, UK, is at the upper limit of the range in developed countries while the strength of wastewater into MSTP, Malaysia, is at the bottom limit of the range in developing countries. These two WWTPs are thus ideal for the study on if wastewater strength plays a role when studying rainfall effects on environmental impacts.…”

“…The ratios of mass and pollutant concentration in dry to wet season were higher in MWTW probably because various pollutants were carried in by stormwater runoff to the treatment plant through a combined sewer system in rainy days (Li et al 2017). According to the review of wastewater strength in developed countries and developing countries (Gallego-Schmid and Tarpani 2019), average influent BOD, COD and SS concentration is 251, 551 and 252 mg/L, respectively, in developed countries, higher than those in developing countries such as 209, 410 and 190 mg/L, respectively. In addition, BOD, COD, SS, N and P vary in wide ranges in either developed or developing countries.…”

A Framework for Sustainable Planning and Decision-Making on Resource Recovery from Wastewater: Showcase for São Paulo Megacity

“…Local context characteristics should be carefully examined and considered in the planning process for resource recovery [7,26]. Especially in developing countries, there is insufficient planning to include efficient sanitation systems [27]. Many technical options are available to recover resources from wastewater and sludge; however, some technologies might not be suitable for developing countries, because of the costs and requirements on treatment processes and energy demand [28].…”

“…In developing countries, the most common routes for sludge disposal are landfilling and agricultural application [27]. These countries usually have little or no waste management infrastructure; therefore, properly controlled co-processing can be a practical, cost-effective, and more sustainable option instead of landfill and incineration [165].…”

Assessment of socioeconomic inequality based on virus-contaminated water usage in developing countries: A review

“…In order to prevent and contain diseases, accessibility to water and sanitation is essential to combating the virus and maintaining the good health and well-being as contained in the Sustainable Development Goal 3. Thus, to attain the United Nations (UN) sustainable development goal 6 “Clean Water and Sanitation” by 2030, a substantial attempt in the creation and management of wastewater treatment plants (WWTPs) should be put into operation in these less developed countries in the subsequent years ( Gallego-Schmid and Tarpani, 2019 ; Nhamo et al, 2019 ; UN-Water, 2017 ). Considering the current global pandemic caused by the novel coronavirus (SARS-CoV-2) with several studies indicating its possible persistence and potential risk in water environment coupled with the existing endemic of waterborne related infections and diseases, especially those resulting from the ingestion of virus-contaminated water, a review focusing on the assessment of differential inequality of virus-contaminated water use in developing countries is essential.…”