Improvement of thermodynamic efficiency of the humid biofuel application in the distributed generation power suppliers

Abstract

The problems of the humid biofuel application in the distributed energy engineering facilities are considered. Use of drying (and thermal proceeding) in energy saving makes it possible to perform efficient biofuel gasification, compensating for, in many cases, the negative influence of the moisture on the efficiency of the energy facilities. The complicated functional connection between the drying and the gasification processes as well as of the gasification product purification are analyzed. The cold purification, taken as the basic technology, reduces the efficiency of the gasification versions with the temperature above the level of the liquid slag removal; yet, if the temperature is not higher than the ash softening beginning, then this influence is insufficient. When compared, the efficiency of the STIG steam-gas facility on the humid fuel tends to be just a little lower than the dry fuel and reaches 45–49%. The calculations show that, at the low gasification temperature, we should not remove all the fuel moisture if the humidity is below 40%. The oxygen blast application in the gasifier reduces the efficiency to some extent but oxygen is necessary to accumulate the highenergy synthetic gas, in particular, for the peak or the exterior application.