Analysis of the Efficiency of Circuits using Natural Gas Additional Energy Potentials on Cogenerating Boiler Houses with Internal Combustion Engines

The article studies the energy efficiency of various circuits using the energy of natural gas excessive pressure in expander-generator units installed before gas reciprocating engines in cogeneration boiler houses. The circuits with and without gas heating before the expander are considered. As an energy effect from the expander use at the cogeneration boiler house fuel economy is taken as compared with the circuits with gas throttling with constant production schedules of electrical and thermal power. The dependence on specific fuel economy determination is obtained. For the circuits being compared, the areas of the energy effect magnitude dependence on the outside temperature are allocated. It is shown that the circuit with heated gas before the expander will have the greatest energy effect at the outside air temperature up to the value corresponding to the equal values of specific fuel economy for the considered circuits and with disconnection of gas heating at higher air temperatures. The method proposed in the paper can be used to calculate the energy effect from various circuits of the expander application in cogeneration boiler houses with internal combustion engine both in exisiting ones and the ones which are under design.