The changes of structures and macerals of hard lignite during non-binder briquetting

In this paper a new technique is developed to convert hard lignite into briquets. Coal samples with Late Jurassic age were collected from the Zhalanoer mine. In a specially manufactured briquetting machine, the low quality lignite has been converted into a clean fuel with high strength and low moisture content, and the heating values increased by 1000 Kcal/kg. Huminites of briquets become soft and deformed during briquetting process. Importantly, the maceral groups gave rise to strong fluorescence during heating under certain pressure. Many new macerals were also produced, such as bituminite, terpenite and fluorinite, all of which may act as a part of binders. It is i implied in this paper that the mechanics of briquetting follows the rules of creep mechanics rather than that of the Hooke’s law.