Two-stage producer gas and its applications 

GT V01 1960 260-267

A brief historical introduction surveys the improvements in gas producers and the development of two-stage generators during the last twenty years. The principles of the two-stage generators are discussed and the separation of the process of distillation of the volatile products from the gasiffcation of the coke by the steam/ air blast is described. The practical development of commercial plants for the production of three types of producer gas (hot raw gas, hot detarred gas and cold clean gas) is described. Typical operating data are given and the utilization of the gas is discussed. The methods of gas cleaning and treatment of by- products are described. The two-stage method of gasification enables the by-products to be obtained in easily handled form, thus enhancing their value, and at the same time reduces effluent to a minimum. The disposal of effluent is described. The types and range of brown and bituminous coals which can be gasified in the two-stage producer are described and illustrated by reference to the fuels now being gasz9ed in two-stage plants in various parts of the world. This leads to a discussion of thermal efficiency both in respect of the gas and the by-products. Reference is made to the particular advantages of the two-stage producer which are helpful in fulfilling the requirements of the Clean Air Act 1956 and which can- not be realized with conventional single-stage producers. In the last part of the paper attention is paid to the economic questions relating to the production and utilization of two-stage producer gas.

S. Kruszewski

A. H. O. Johnson