Авіаційно-космічна техніка та технологія (Aug 2020)
INCREASING THE EFFICIENCY OF HYDROGEN PRODUCTION TECHNOLOGY BY USING A REGENERATION CIRCUIT WITH A ROTARY-PISTON EXPANDER MACHINE
Abstract
The article discusses a promising technology for the production and safe accumulation of hydrogen from the Black Sea hydrogen sulfide, which includes the following processes: production of hydrogen sulfide from the depths of the Black Sea; separation of hydrogen sulfide and seawater; destruction of hydrogen sulfide to produce a hydrogen-containing gas; separation of hydrogen from a hydrogen-containing gas; safe hydrogen storage; safe transportation of hydrogen. It is proposed to use the regeneration circuit to increase the efficiency of this technology, which includes: an expansion machine for high-pressure hydrogen sulfide, a seawater hydraulic turbine, and a heat pump installation. It is proposed to evaluate the efficiency of the application of the technology for the production and safe accumulation of hydrogen from the Black Sea hydrogen sulfide by effective capacity, which includes: thermal power of hydrogen, power of the regeneration circuit; the power needed to carry out hydrogen production processes. It is proposed to use the 20RPD-4.4/1.75 rotary piston engine as a hydrogen sulfide expansion machine that will satisfy all the requirements. Rational operating modes and limiting values of the efficiency of using the technology for obtaining and safe accumulation of hydrogen from the Black Sea hydrogen sulfide for daily hydrogen production of 200 kg/day were determined depending on the degree of hydrogen sulfide conversion during destruction, the gas content of hydrogen sulfide in seawater and the depth of immersion of the lifting pipeline using the regeneration circuit. The minimum permissible degrees of conversion at which the efficiency of using the technology for obtaining and safe accumulation of hydrogen from the Black Sea hydrogen sulfide for a gas content of hydrogen sulfide of 2.5 m3/m3 at a depth of immersion of the lifting pipeline of 250...1000 m is 0.427 ... 0.413, for 5 m3/m3 – 0.375...0.363, for 7.5 m3/m3 – 0.363...0.350, for 10 m3/m3 – 0.356...0.343. The use of the regeneration circuit allowed us to reduce the minimum permissible degrees of conversion for the gas content of hydrogen sulfide of 2.5...10 m3/m3 at a depth of immersion of the lifting pipeline of 250...1000 m by 0.136 ... 0.069.
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