Experimental and Process Design Study of a Fast Pyrolytic Gasification Process. Quarterly Technical Report No. 5,April--June 1975.

摘要

A total of 55test runs have been made with the experimental entrainment gasifier to date. Early tests revealed several equipment problems. The rotary feeders originally designed for feeding the coal were unsatisfactory for pressurized feeding. The coal injectors were subject to plugging by slag deposition. Overheating and melting of the combustion stage refractory insulation was encountered. Plugging was encountered in the heat recovery exchanger and in the gas scrubber. Satisfactory feeding of the pulverized coal has been achieved with auger-driven feeders aided by pneumatic vibrators. Relocating the pyrolysis coal injectors near the top of the combustion stage and the use of a low feed rate relative to the combustion coal feed rate eliminated char plugging and permitted conversion efficiencies of from 59-71percent and heat values of 317-336BTU/SCF. A critical review was made of prior work with entrained flow gasifiers. A series of parametric equilibrium calculations were made to study the effect of varying mixture ratios and the equilibrium temperature on the performance of the combustion stage of the present gasifier. A thermodynamic analysis was made of three different methods for cooling the gasifier combustion products. A preliminary design study was made of a commercial scale gasifier having a throughput capacity of 25tons per hour with detailed cost estimates for the equipment required. (ERA citation 01:018437)