In the State Register of Inventions of the Russian Federation, patent for invention No. 2639701 "Method of utilization of acid gases containing hydrogen sulphide and ammonia by the Claus method below the dew point" is registered.
The invention relates to the field of chemistry and can find application in the utilization of hydrogen sulphide in the oil, gas, oil refining industry, as well as non-ferrous metallurgy and, in particular, in the processing of acid gases.
The technical task solved by the patented JSC «Giprogazoochistka» method is to reduce costs by optimizing the process design of the process by heating the process gas and carrying out hydrolysis reactions in a combined catalytic apparatus that is uniform for the Claus reactors of the catalytic stage while maintaining a high degree of sulfur recovery.
A key feature of the developed domestic desulfurization technology is a high degree of utilization of harmful gases, exceeding 99.5%. This does not require expensive (in comparison with existing foreign analogues) post-treatment, which significantly reduces the costs of plants during construction and operation. Solving environmental problems from JSC «Giprogazoochistka», based on the experience of successful implementation of hundreds of projects, will allow Russian enterprises to reduce costs for environmental protection.
Considering the new rules for controlling emissions and minimizing the toxic effects on the atmosphere, the new technology will solve the problems of both refiners of oil and natural gas, and owners of factories around the world.
The development and start of production of units using domestic technology JSC «Giprogazoochistka» will be the first and certainly an important step in solving a complex of problems of licensing technologies in the oil and gas sector of the country, as well as a prospect for the development of export potential.
The invention relates to a method for the utilization of acid gases containing hydrogen sulphide and ammonia, according to the Claus method below the dew point, including the thermal and catalytic steps.
The raw acid gas is sub-stoichiometrically burned in a Claus furnace, the heat obtained is utilized in the recovery boiler, followed by separation of the liquid sulfur in the condenser, and the process gas leaving the thermal stage is fed to the catalytic stage where it is heated and passed through at least two successively mounted reactors Claus with built-in heat exchangers for the removal of Claus reaction heat, between which elements an alumina catalyst is filled. Reactors operate cyclically with periodic sequence switching. One of the Claus reactors operates at a temperature above the dew point of sulfur, and the other at a temperature below the dew point.
The process is carried out using a combined catalytic reactor installed at the inlet to the catalytic stage and comprising a preheating zone and a catalytic zone where at a temperature of 300-350 ° C hydrolysis of COS and CS2 takes place and alternately works in pairs with each of the Claus reactors in the mode above the dew point of sulfur. The combined catalytic reactor is equipped with a titanium oxide catalyst. In the first in the course of the Claus reactor, a temperature gradient of 300-250 ° C is maintained above the sulfur point, and in the second in the course of the Claus reactor a temperature gradient of 155-115 ° C is maintained, while the inlet temperature is maintained above the sulfur dew point by at least 5 ° C, at the outlet - below the dew point of sulfur. To increase the efficiency of condensation of sulfur on the catalyst, an alumina catalyst of different porosity is filled into the Claus catalytic reactor. In the upper part of the layer of the alumina catalyst, the ratio of the volume of micropores and mesopores to the volume of ultramacropores does not exceed 5, and in the lower part it is more than 10.
All this in general provides an increase in the degree of sulfur recovery to 99.5-99.7%.