Mohamadali Mohit , Masoud Makian , Om Prakash , Gyeongcheol Kim , Hojung Rho , Jong-Han Lee , Dong-Hoon Kim
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引用次数: 0
Abstract
Methane (CH4), a potent greenhouse gas (GHG), is a major concern in sewer pipelines, and its emissions can increase with food waste (FW) introduction via disposer systems. To mitigate these emissions, several chemical approaches have been attempted, yet they face environmental and economic challenges. In this study, ultrasonication was applied inside sewer pipelines at different intervals (30 min once every 4, 5, and 6 weeks) to evaluate its long-term effect on CH4 emission reduction. Two lab-scale gravity sewer pipelines (7 m long, 80 mm diameter) were constructed and fed with: only domestic wastewater (R1) and domestic wastewater plus FW (R2). FW addition increased CH4 emissions from 52 to 110 mL CH4/Lsewage, due to higher organics entering the sewer pipelines (500→1000 mg COD/L). Following ultrasonication, CH4 emissions decreased by 40–56 % and 34–39 % in R1 and R2, respectively, attributed to biofilm detachment, as confirmed by changes in extracellular polymeric substances concentration and shear stress test. The average daily GHG reduction by ultrasonication was 10.5, 9.2, and 7.7 g CO2 eq./d for R1, and 15.8, 14.6, and 13.9 g CO2 eq./d for R2, at 4-, 5-, and 6-week intervals, respectively, clearly indicating a revival in CH4 emissions. Considering the energy use, net GHG reduction effectiveness significantly dropped with longer intervals in R1 (38→28 %), while remaining relatively stable (28–30 %) in R2. These results emphasize the importance of shortening ultrasonication intervals, particularly when only domestic wastewater is conveyed in the sewer pipelines.
期刊介绍:
Environmental Technology & Innovation adopts a challenge-oriented approach to solutions by integrating natural sciences to promote a sustainable future. The journal aims to foster the creation and development of innovative products, technologies, and ideas that enhance the environment, with impacts across soil, air, water, and food in rural and urban areas.
As a platform for disseminating scientific evidence for environmental protection and sustainable development, the journal emphasizes fundamental science, methodologies, tools, techniques, and policy considerations. It emphasizes the importance of science and technology in environmental benefits, including smarter, cleaner technologies for environmental protection, more efficient resource processing methods, and the evidence supporting their effectiveness.