1 Interdisciplinary Graduate School of Energy Systems (IGES), Prince of Songkla University, Hat Yai, Songkhla, Thailand.
2 Environmental Protection Department, Environmental Management Agency, Harare, Zimbabwe.
Waste Manag Res. 2019 Jan;37(1):83-94. doi: 10.1177/0734242X18804029. Epub 2018 Oct 25.
The recovery of energy from municipal solid waste (MSW) has gained popularity in many industrialized countries, but its adoption in economically developing countries, especially in Africa, has been slow. While capital investments and technical requirements for waste-to-energy (WtE) systems are among the most important causes for this slow adoption, the unavailability of data on the thermochemical quality of MSW as a potential feedstock for energy recovery is also a limiting factor. In this paper, Harare, a typical African city, was selected as a case study. The evaluation was based on the analysis of the MSW's composition, moisture as-discarded, thermochemical properties and energy content. The results show that the quality of the MSW is comparable to that in regions outside Africa where WtE has been a success. The combustible fraction exceeded 75 wt% making it ideal for thermal treatment without requiring supplementary fuel. With an MSW throughput of 421,757 tonnes year (11.1% of which is recycled), and a lower heating value of 10.1 MJ kg, the energetic potential was estimated at 3.8 × 10 GJ. MSW thermal treatment via conventional technologies can reduce the waste throughput to landfills by up to 40%, provide up to 112 GWh year of electrical energy, and increase the annual share of electrical energy produced from bio-fuels and wastes from 1.3% to at least 2.2%. These benefits make thermal MSW treatment a suitable option for waste disposal in African cities.
从城市固体废物（MSW）中回收能源在许多工业化国家已经很普遍，但在经济发展中国家，特别是在非洲，其采用速度较慢。虽然垃圾能源化（WtE）系统的资本投资和技术要求是导致这种缓慢采用的最重要原因之一，但作为能源回收潜在原料的 MSW 的热化学质量数据不可用也是一个限制因素。本文选择了非洲典型城市哈拉雷作为案例研究。评估基于对 MSW 的组成、丢弃时的水分、热化学特性和能量含量的分析。结果表明，MSW 的质量与 WtE 已经成功的非洲以外地区相当。可燃部分超过 75wt%，无需补充燃料即可进行热处理。如果每年处理 421,757 吨 MSW（其中 11.1%被回收），低位热值为 10.1MJ/kg，则能量潜力估计为 3.8×10^9GJ。通过传统技术对 MSW 进行热处理，可以将送往垃圾填埋场的废物量减少多达 40%，提供高达 112GWh/年的电能，并将生物燃料和废物产生的年度电能份额从 1.3%至少提高到 2.2%。这些好处使得对 MSW 的热能处理成为非洲城市废物处理的一种合适选择。
