Preliminary investigation on the starch potential as natural binder in the hot binderless briquetting process of torrefied municipal solid waste

Municipal solid waste (MSW) has the great potential to be next generation of solid fuel. However, it has major drawbacks of low calorific value and low bulk density. Low calorific value results smaller energy and the low bulk density develop problems during the handling, transportation, and storage. Combination of torrefaction and briquetting offer solutions for those problems. Torrefaction is the thermochemical process in the inert condition used to produce high calorie solid fuel. Meanwhile, briquetting is a densification process used to increase the bulk density of the powder material. In this research, the process employs starch material contained in MSW as the binder to create agglomeration among the particles. In order to understand the role of starch as binder, this study was initiated by performing binderless briquetting at low pressure employing starch material, rice, as binder and torrefied orange peel as the representative of MSW. The experiment was varied in various parameter such as the rice composition in the briquette, briquetting temperature and rice torrefaction temperature. The products were then evaluated for its quality by comparing its briquette strength using drop shatter test method. The result showed that the optimum rice torrefaction temperature to produce durable briquette from torrefied MSW material was 175 ℃.