Thermal Efficiency Gain Research Articles

Generation of synthesis gas by partial oxidation of natural gas in a gas turbine

The application of partial oxidation in a gas turbine (PO-GT) in the production of synthesis gas for methanol production is explored. In PO-GT, methane is compressed, preheated, partial oxidized and expanded. For the methanol synthesis a 12% gain in thermal efficiency has been calculated for the PO-GT process, while the product cost decrease with 7%. For DME synthesis simular results are achieved. More development on the reactor and turbine are needed to implement this process in the industry.

The Prospects of the Steam Cycle in the Central Power Station

The advent of the gas turbine and its effect on the position of the steam turbine for the central power station is briefly discussed. In the opinion of the author the steam turbine will hold the field for large power generation for many years to come, and there is no immediate prospect of any other form of prime mover becoming a serious competitor for the generation of electricity in the central power station. Data are given indicating the gain in thermal efficiency that can be expected from increased steam conditions up to 2,000 lb. per sq. in., and 1,000 deg. F. with and without reheating. The advantages of reheating as a means of obtaining higher efficiency are strongly emphasized. Methods of operation to enable quick starting are discussed. Some of the principal constructional problems created by high steam conditions are briefly discussed and methods of overcoming the difficulties are indicated. The essence of the paper is to examine, in as simple a manner as possible, the means available for improving the efficiency of the central power station; and in an effort to achieve this, detailed methods of calculation are not included, as it is considered they would detract from a clear appreciation of the results. The minimum of assumptions have been made, so that the curves represent a true picture of the actual gains that could be obtained in practice.

The Increase in Thermal Efficiency Due to Resuperheating in Steam Turbines

Abstract Experience has shown that as the ratio of the number of stages of a turbine operating in the superheated region to the number operating in the moisture region is increased, the actual thermal efficiency is improved at a rate far in excess of the theoretical value. The results of a large number of tests on turbines at different superheats have been analyzed to form a basis for calculating the gain in thermal efficiency due to resuperheating. In this paper, these results are given showing that the heat consumption of a turbine installation may be decreased from 6 to 7 per cent as a result of resuperheating the steam. There seems to be a rather broad pressure range at which the resuperheating may take place in order to show approximately the maximum saving. The probable gain due to more than one resuperheating has been obtained. These results indicate that, when taking into account the pressure drop in the resuperheaters, the gain possible by going to more than two stages of resuperheating would be very small. The effect of resuperheating upon the exhaust conditions and capacity of the turbine is discussed. Curves are presented to show that the gains due to the resuperheating and the regenerative cycles are very nearly independent of each other and that these features may be used in the same turbine, with the expectation that the savings due to both will be nearly additive.