Sustainable Solid Waste Management through 3R Strategy in Gazipur City Corporation

Abstract

With rapid urbanization and population growth, developing countries like Bangladesh are experiencing challenges in municipal solid waste (MSW) management. While developed countries are giving highest priorities in resource recovery from MSW, developing countries are still facing challenges and obstacles to establish proper collection and disposal system. Gazipur City Corporation (GCC) is recently formed city corporation in Bangladesh and this city is widely known as one of the major industrial zones of the country. As the city urbanizes, the city corporation is over burdened with the solid waste management. There has been very limited study on this city and reliable data are required to plan and design appropriate management system. To obtain reliable data on solid waste in GCC area a study was carried out and main objective of the study was to determine household solid waste generation, composition, potential for resource recovery, economic benefit and landfill area saving. A questionnaire survey was also conducted to find the waste management behaviors, and their attitudes and willingness to participate in household solid waste management. In order to achieve the proposed objectives, total 206 and 30 waste samples were collected from households and secondary dumping sites (SDS) respectively. Waste was collected both in dry and wet season. The waste was separated mainly in two categories like organic (food waste, garden waste) and inorganic (paper, plastic, metal, glass, leather etc.) contents. The study reveals that the solid waste generation rate at household level is 0.36 kg/capita per day accumulating 717.5 tons of solid waste daily in GCC area. Seasonal variation of waste generation was also computed for dry season (0.352kg/capita/day) and wet season (0.364 kg/capita/day). The waste in household mostly comprised of organic contents (83.4%) followed by plastic (6.34%), paper (5.75%), glass (0.91%), leather & rubber (0.66%), metal (0.62%) and others (2.27%). Whereas in secondary sites it was found that organic content (77.04%) was less than the weight percentage found in households. This study emphasizes on the 3R based solid waste management system which promote waste reuse and recycle through recovery of resources from the waste stream. It has been found that a significant portion of waste can be recovered as recyclable materials which accounts 2 for 38000 ton annually having a market value of 154.35 million BDT. Potential recoverable waste have a14.5% volumetric reduction rate which will reduce the required number of trips for collection vehicle from 254 to 216 per day saving fuel cost equivalent to 8 million BDT. Furthermore, with 3R approach land filling area requirement can also be reduced over the time and it is estimated that almost 7 acres of land area can be saved by 2036 with 100% resource recovery rate. With existing management practices, GCC require 407 BDT/ton for collection, transportation and disposal purposes. Recovering potential recoverable materials will allow to generate a revenue over 163 million BDT annually (624 BDT/ton). The major drawback of the current solid waste management system is that there is no practice of waste segregation both at household level and secondary dumping sites. Also the existing system is only limited to waste collection from SDS and dumping at the final disposal site. No further treatment of waste is carried out formally. This study proposes an approach for integrated solid waste management (ISWM) system to minimize the current shortcomings of the management system based on 3R strategy. The proposed approach allows waste to segregate at source based on color code and suggests modification in the primary collection vehicle. The recommended method for treatment of organic waste is composting/anaerobic digestion. However, this study does not encompasses the waste generated from commercial, industrial and other sources. Further study can be carried out to determine overall MSW generation and composition. Also adequate awareness campaign shall be designed for spontaneous involvement of public in practicing 3R based waste management.