SU912243A1 - Method of drying hydrogen sulphide containing gas - Google Patents

Description

This invention relates to a gas drying technique and can be applied to ocyiuKH hydrogen sulfide-containing natural or associated petroleum gas.

A known method of drying the gas includes the first contacting of the gas with the absorbent, the separation of the absorbed gas from the saturated absorbent, the regeneration of the absorbent followed by its recirculation to contact with the gas and the release of non-condensable gases from the regeneration stage, according to which it is proposed to blow hydrogen sulfide from the absorbed absorbent in a special column using sulfur-free gas, and the stripping gas, saturated with hydrogen sulfide, is returned to the main stream of gas entering the drying system 1.

The disadvantage of this method is the need to supply a sulfur-free gas from an external source, which significantly increases the cost of the process. In addition, the size of the stripping column is very significant, since the stripping takes place at high pressure (equal to the pressure in the absorber), and large diameter and height of the packing in the column are required to ensure efficient mass exchange of the stripping gas with the saturated absorber. Also, this method does not solve the problem of preventing hydrogen sulfide-containing gas from escaping into the atmosphere from the regenerator together with water vapor, which enters the regeneration unit along with the overall absorbent, since it is impossible to completely blow off the sulfur in the stripping column.

The closest to the proposed technical essence and the achieved result is a method of drying the gas by contacting it with

15 absorbent, discharging from a saturated; Absorbent gas absorbed by it by reducing the pressure of the absorbent and weathering the gas, regeneration; absorbent under vacuum, return

20 it to the stage of contacting with the gas, separating the non-condensed gases from the stage of regeneration and injecting them with a stream of graded sorbent. This method eliminates

25 the need to supply a sulfur-free stripping gas; the size of the apparatus for separating the absorbed gas from the saturated absorbent material (low weathering

Claims (2)

30 pressure instead of the stripper). and it is also completely warned of the discharge into the atmosphere of non-condensable hydrogen sulfide-containing: elements from the regeneration stage 2. The disadvantage of this method is that it is impossible to return the gas to the stage of contact with a6ccjp6eHTQM, since the pressure in the Purifier is lower than the pressure in the manifold. In addition, this gas contains more than 1 liter of hydrogen sulphide, which prevents it from being used for its own needs by a plant and drying (for example, as fuel for a regenerator or a desorption gas). Therefore, in the case of drying of the sulfur-containing gas by the considered method, the weathering gas is flared, t, e. irretrievably loses p. The purpose of the invention is the elimination of hydrogen sulphide losses. The post-agglomera goal is achieved by — according to the method of —susifying the hydrogen-containing gas of the gas, including an absorption with a chi-glycol, separation from the saturated absorbed hydrogen absorbed by it, regeneration is absorbed / under vacuum, recycling it to the absorption stage and the release of uncondensed regeneration gases by injecting a gas stream from the absorption stage, the injection leads to two stages, and in the second stage, as a working flow, using a regenerated absorber, while the injection is egenerirovann№1 absorber RCT pressure of 25-250 kgf / cm. The proposed method allows saving capital costs and eliminating the loss of hydrogen sulfide-containing gas due to the possibility of using weathering gases that were previously flared, Example 1. Associated non-gas 3 of 500 thousand with a hydrogen sulfide content of 0.5% of dryness. absorber, regenerated with 98.56% diethyl {glycol {DEG} at a pressure of 6 kgf / cFvi and a temperature of 20 ° C, DEG consumption of 2 m- / h, V natant DEG (concentration 96 May.%) under absorption conditions dissolves 10 nm / h of gas, which contains 58 vol. % of hydrogen sulfide. After reducing the pressure to 1.5 kgf / cm, 5 m / h of absorbed gas is extracted from the saturated absorbent in the weather, the remaining 5 m / h which is removed, the gas goes to the regenerator together with saturated glycol. During the regeneration of the absorbent, this gas is removed together with the evaporated water, the coolant is separated from the separator in the separator and injected to the flow of pei-generated DEG supplied by the pump to the absorber. A gas weathered from the saturated DEG in a weathering device is also injected. Since the pressure in the absorber is small and the amount of gas absorbed by the absorber is small, gases can be injected in one step. The second injector is not applicable in this case. The mixture of regenerated DEG and injected gas is returned to the absorber. Example 2. Natural gas in the amount of 3 million with a hydrogen sulfide content of 6 vol. % is dried in the absorber with regenerated 99.5% dung1 DEG at a pressure of 80 kgf / cm and a temperature of 40 ° C. DEG consumption 10. In saturated DEG (concentration 97%), under conditions of absorption, 140 nm / h of gas containing 44 vol. % of hydrogen sulfide. After reducing the pressure to 2 kgf / cm from the saturated absorbent, 123 absorbed water is absorbed from the saturated absorbent. The rest of that 1 / nm / h of gas goes to the regenerator along with saturated glycol. When absorbent is regenerated, this gas is removed along with the evaporated water, cooled, separated from the water in the separator, and injected into the injectors sequentially, first with a dried gas stream and then with the regenerated DEG stream supplied by the pump for recycling to the adsorber. A gas weathered from the saturated DEG in the exhauster is also injected. Thus, all the gas (140) absorbed by the glycopene in the absorber is returned to the contacting stage together with 10 m / h of regenerated DEG (this GS13 is then combined with the main ocyiiieHHoro gas stream.) The proposed spasse; gas drying can be used in typical gas treatment facilities with a hydrogen sulfide content of 1, J and 5 million nm- / day capacity, and 3-ayo-gas-based hydrogen sulfide hydrogen discharge devices: 1 live gas with a capacity of 100; 200; 300 and 500 thousand. Expected annual economic effect from using Approximately 3 thousand rubles. Claim 1, Method of waspsu hydrogen sulfide permeates a second-piece counterstep, an example of which is glycol absorption, separation of absorbed hydrogen sulfide from a saturated absorber, regeneration of an absorber under vacuum, its recirculation to the absorption stage and separation of an uncondense condensation under vacuum, and recirculation of the absorber under vacuum. gas flow through the absorption stage, characterized in that, in order to eliminate the loss of hydrogen sulfide, the regeneration gases after injection are directed to the additional stage th injection by utilizing as working stream of the regenerated absorber. 2. The method according to claim 1, characterized in that the injection the regenerated absorber is carried out at a pressure of 25-250 kgf / cm. Sources of information taken into account in the examination 1. Patent IT No. 3069829, cl. On 01 D 53/26, published 1973. 2. Authors certificate of the USSR 466039, cl. B 01 D 53/26, 1975 (prototype).