Application of Thermo-chemical Technologies for Conversion of Associated Gas in Diesel-Gas Turbine Installations for Oil and Gas Floating Units

Abstract

The paper considers the issue of thermo-chemical recovery of engine’s waste heat and its further use for steam conversion of the associated gas for oil and gas floating units. The characteristics of the associated gas are presented, and problems of its application in dual-fuel medium-speed internal combustion engines are discussed. Various variants of combined diesel-gas turbine power plant with thermo-chemical heat recovery are analyzed. The heat of the gas turbine engine exhaust gas is utilized in a thermo-chemical reactor and a steam generator. The engines operate on synthesis gas, which is obtained as a result of steam conversion of the associated gas. Criteria for evaluating the effectiveness of the developed schemes are proposed. The results of mathematical modeling of processes in a 14.1 MW diesel-gas turbine power plant with waste heat recovery are presented. The effect of the steam/associated gas ratio on the efficiency criteria is analyzed. The obtained results indicate relatively high effectiveness of the scheme with separate high and low pressure thermo-chemical reactors for producing fuel gas for both gas turbine and internal combustion engines. The calculated efficiency of such a power plant for considered input parameters is 45.6%.

Investigation of the Combustion Processes in the Gas Turbine Module of an FPSO Operating on Associated Gas Conversion Products

“…Investigations carried out earlier by the current authors have made it possible to identify the main parameters that influence the process of associated gas conversion [26]. It was found that an increase in the process pressure leads to an increase in the temperature, which is necessary for effective conversion.…”

“…Associated gas was adopted as the initial fuel, with the following composition (vol. ): methane (CH 4 ) 62.8-73.7%; ethane (C 3 H 8 ) 6.7-17.7%; propane (C 2 H 6 ) 6.1-9.0%; butane (C 4 H 10 ) 2.4-5.0%; pentane and heavier (C5+) 1.0-3.7%; carbon dioxide (CO 2 ) 0.6-9.2%; nitrogen (N 2 ) 0.0-4.4%; hydrogen sulfide (H 2 S) 0.0-2.8 [26,28]. Since the gas temperature behind the steam generator was above the dew point temperature, the maximum allowable steam/gas mass ratio was 6-7, depending on the composition of the associated gas.…”

Application analysis of a hybrid solid oxide fuel cell-gas turbine system for marine power plants

“…Two 250 kW high-temperature SOFC systems working with methanol were integrated within the ship supplying electrical energy. Cherednichenko and Serbin (2018) and Cherednichenko et al (2019) analysed the capabilities of thermo-chemical technologies for the conversion of different hydrocarbons on ships. As reported by Sun et al (2010), the SOFC-GT system for the Large Medium Speed Roll-on/Rolloff sealift ship has significant potential in reducing nitrogen oxides emission and fuel consumption.…”

Research of Low-Emission Associated Gas Combustion in the Gas Turbine Engine of a Floating Production, Storage and Offloading System

“…The applicability of thermo-chemical technologies for converging of associated gas in diesel-gas turbine installations for oil and gas floating units was considered in [8]. To describe the processes in the combustion chamber of a gas turbine engine working on synthesis gas, a mathematical model with detailed 35-reaction chemical mechanism was used.…”

“…To describe the processes in the combustion chamber of a gas turbine engine working on synthesis gas, a mathematical model with detailed 35-reaction chemical mechanism was used. The disadvantage of the proposed in [8] calculation model is the impossibility of predicting the higher hydrocarbons burning-out, which play a significant role in the associated gas oxidation process.…”