Analysis of the Effect of the Use of Food Waste Disposers on Wastewater Treatment Plant and Greenhouse Gas Emission Characteristics

Abstract

The introduction of food waste disposers (FWDs) has been discussed in various countries, and in Korea, a method for utilizing FWDs has been considered. The results of the study show that the use of FWDs is more eco-friendly and economical than other forms of food waste (FW) disposal. However, there are also studies showing that FWDs are worse, for example, they aggravate water pollution and deteriorate the function of municipal wastewater treatment plants (WWTPs). Therefore, this study analyzed the concentration of pollutants of wastewater from FWD and the effect on the operation rate and GHG emission of WWTP when FW was introduced into the sewer by FWD using operation data for each WWTP. As a result of the analysis, when FWD was used, facilities exceeding the appropriate operation rate accounted for 86% of the total WWTP, and net-GHG emissions increased by 58%. Through this, FWD wastewater showed much higher contaminant concentrations than regular wastewater; thus, the introduction of FWD in the current situation will have a negative effect on maintaining the function of WWTP and reducing GHG. To introduce FWDs, improvement in WWTPs regarding pollutant load and discharge characteristics of FW and input of digestion systems through a separate FWD pipe, the introduction of high-efficiency energy facilities, and the recycling of wastewater sludge are necessary to reduce GHG emissions.