The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 20, 1996
Filed:
Nov. 18, 1994
Stanley J Selle, East Grand Forks, MN (US);
Douglas R Hajicek, Grand Forks, ND (US);
Michael D Mann, Thompson, ND (US);
Nanak S Grewal, Grand Forks, ND (US);
Energy and Environmental Research Center Foundation, Grand Forks, ND (US);
Abstract
A process of improving overall quality of coals or other solid fuels comprising heat treating those coals in a controlled, spontaneous, fluidized bed reactor system. The bed system is of such a geometry that in combination with the control system a higher velocity region exists where the fluidizing gas and fuel are fed than where the treated solids exit. The offgas exiting the top of the reactor has a velocity of the average of the inlet gas velocities. Treated coal is withdrawn intermediate to top and bottom. Residence time is controlled by the amount of the solid fuel feed, the location of the treated solid fuel overflow, and the temperature is maintained by oxygen to flue gas ratio, feedstock size and fluidizing velocity. The unit can be operated in a drying mode or a devolatilization mode, to control volatiles, moisture and fines.