Patent DE-102010053593-A1 (DE)
Title: Binderless briquetting of hard brown coal, bituminous coal and similar coals comprises processing raw coal, drying raw coal, treating dry coal, briquetting and treating briquette
Inventor: MINYAN FU
IPC: C10L5/08
Filed: 2010-12-07
Abstract: Binderless briquetting of hard brown coal, bituminous coal and similar coals comprises: (a) processing raw coal; (b) drying raw coal; (c) treating dry coal; (d) briquetting; and (e) treating briquette. The raw coal is initially screened to a particle size of = 6.3 mm and present oversized particles are crushed in a hammer mill (3). The crushed raw coal is dried in a steam-heated tube dryer (6) for soft brown coal to a final water content of 9-11 mass% with the use of hard brown coal and 1-3 mass% with the use of bituminous coal. Binderless briquetting of hard brown coal, bituminous coal and similar coals comprises: (a) processing raw coal; (b) drying raw coal; (c) treating dry coal; (d) briquetting; and (e) treating briquette. The raw coal is initially screened to a particle size of = 6.3 mm and present oversized particles are crushed in a hammer mill (3). The crushed raw coal is dried in a steam-heated tube dryer (6) for soft brown coal to a final water content of 9-11 mass% with the use of hard brown coal and 1-3 mass% with the use of bituminous coal, where the tube dryers relative to a known tube dryers for soft brown coal and apparatus is modified technologically. The dried and tempered coal is further crushed to an optimum particle size of = 0.5 mm in the tube dryers at 70-90[deg] C for briquetting by means of a steam-heated reservable impact hammer mill in collaboration with a suitable sifter, where the dry coal and oversized particles are added for treating the briquette. The briquetting of the processed dry coal is carried out by a two-roll press (18) exhibiting: a particle size of the dry coal of = 0.5 mm; water content of the dry coal of 9-11mass% with hard brown coal and 1-3 mass% with bituminous coal; temperature of the dry coal at 70-90[deg] C; pressure of 140-180 MPa; specific pressing force of 150 kN/cm; and pressing material vaporization prior to the pressing, where a scabs band is formed by an scabs crusher, which is designed as two-roll crusher, are divided into individual briquettes. The scabs break and the trickle coal from the two-roll press are sieved from the individual briquettes as an end product of the method and the dry coal is mixed in the region of the treating dry coal. An independent claim is also included for a plant for binderless briquetting of hard brown coal, bituminous coal and similar coals, where a bunker (1) with overlapping raw coal with a maximum particle size of 60 mm is connected downstream to a sifter (2) for separating the passage particle with a particle size of = 6.3 mm from the oversized particle and the hammer mill is installed for crushing the oversized particles to = 6.3 mm. A bunker is provided for temporary storage of the crushed raw coal with a particle size of = 6.3 mm. The bunker is connected downstream to the steam-heated tube dryer for drying the processed raw coal to the final water content of 9-11 mass% with the use from hard brown coal and 1-3mass% with the use of bituminous coal, and the tube dryer is associated with an electrostatic precipitator for the disposal of the resulting vapor and for returning the separated dry coal dust in the method. The drying is followed by the region for treating dry coal comprising the steam-heated reservable impact hammer mill with upstream- and downstream rotary valves, where the treated dry coal leaves the impact hammer mill with the particle size of = 0.5 mm. The impact hammer mill is connected downstream to a vibrating channel and one sifter in the form of a multiple-deck or a sizer for separating the oversized particles (greater than 0.5 mm) from the desired particles (less than 0.5 mm), where a bunker is provided for storage of the desired particles and a transporting device is provided for the reintroduction of oversized particles in the method. The at least warm dry coal at 70[deg] C after pressing is realized to scabs band by the two-roll press with pressing material vaporization prior to the pressing. The scabs crusher is formed as the two-roll crusher provided for breaking the scabs band into individual briquettes. The scabs crusher is followed by a further sifter for separating resulting fine particle from the individual briquettes during the pressing and crushing, where the fine particle in the region for treating dry coal is introduced back into the method.