Development of a biomass gasifier which uses the superheated steam and its application to micro co-generation system

Abstract

Micro scale gasifier of biomass, which are refuse derived fuel and wood pellets, using the superheated steam has been developed and the feasibility of the generation pyrolysis gas as a fuel for micro co-generation was verified. The thermal cracking experiments were conducted at the superheated steam temperature from 500 to 700 degree C. The quantitative analysis of pyrolysis gases were carried out and residue amounts of char and tar were determined. Moisture and tar in the pyrolysis gas were removed by a cooling device which was kept at 0 degree C. The calorific values of the pyrolysis gases were about 14 to 19 MJ/Nm3, and were 1/3 to 1/2 than that of town gas(13A). Then, the refined gas was supplied to a micro gas engine of 1 kW output as a fuel. The experiments were conducted repeatedly by changing the mixture ratio of pyrolysis gas and town gas. As a result, it turned out that the mixture of 13% of pyrolysis gas to the town gas is possible under keeping constant power output.