SU1608109A1 - Method of cleaning blow off gases of wells from hydrogen sulphide - Google Patents

Abstract

The invention relates to the purification of gases from hydrogen sulfide and can be used in the development of wells in natural hydrocarbon gases with a high content of hydrogen sulfide. To ensure effective purification of gases containing 30-50 vol.% Of hydrogen sulfide in one step, oxidation of hydrogen sulfide with oxygen in an amount of 100-110 vol.% Of the stoichiometry on the catalyst — magnesium chromite on supported alumina — is carried out (magnesium chromite content is 10-20 wt.), taken up in the form of spherical granules with a strength of 165-520 kg / cm ² , and the oxidation process is carried out in a fluidized bed of catalyst at 250-350 ° C. The method provides a degree of gas purification from hydrogen sulfide of 98-99%, while the degree of conversion of hydrogen sulfide into sulfur is 98-100%. 1 hp pf, 2 tab.

Description

The invention relates to the purification of gases from hydrogen sulfide and can be used in the development of a well in fields of natural hydrocarbon gases with a high content of hydrogen sulfide.

The purpose of the invention is to ensure the purification efficiency when the hydrogen sulfide content in gases is 30-50 vol.

Example 1. The catalysts used in the proposed method are catalysts of a supported type. Alumina of various modifications is used as a carrier. In tab. 1 shows the comparative

strength characteristics of the used catalysts.

Experimental conditions. Studies of the oxidation of hydrogen sulfide are carried out on a flow-through installation with a fluidized bed of catalyst. Temperature range of tests is 250-350 C. The reaction mixtures are analyzed for the content of Og, N, H ,, S, SO., SNd, 00, CO COS, NW by gas chromatography.

Conditions for analysis. At-. boron - LHM-8 MD chromatograph with two parallel columns. The sorbents are molecular sieves and poropak Q. The carrier gas is helium. Nasi5 gas velocity

About 00

about with

tel 30 ml / min. Working temperature of the column sorbents: zeolites NaX 20 ° С, poropak Q,

The amount of air required for the oxidation of hydrogen sulfide is calculated by the formula:

Vg. , 760.5 "V -C / tOO,

the amount of air required for the oxidation of hydrogen sulfide, l / h; air volume containing

1 volume of oxygen; oxygen stoichiometric ratio

-L about 2 years

S, + H ,, 0,

VP - the amount of hydrogen sulfide-containing gaga, l / h; C is the concentration of hydrogen sulfide,

crOf

oo; Sf, - sulfur gas.

To start the apparatus, the catalyst bed is preheated to, after which the stripping gas is fed into the layer in separate streams, containing up to 30-50 vol. and air in an amount close to stoichiometric. The reaction proceeds at 250-350 seconds. Excess heat is removed by a heat exchanger immersed in a fluidized bed of catalyst. In the decontamination process, the degree of conversion of hydrogen sulphide into sulfur is over 97%.

The source gas contains,%: 30; COj 2; CH 68. After mixing the source gas with air in a volume ratio of 1: 0.72 into a reactor containing 5 g of catalyst (composition 1 according to table 1, the content of magnesium chromite is 10 wt.%) At temperature and Vo6. 3600 serves a mixture of composition, vol.%: H, s 17,5; 0 8.8; N2 32.5; SSg 1,2; methane rest; оС 1.0. (06 - coefficient of excess Og in relation to HjS by the reaction: + Sp +).

The degree of purification from hydrogen sulfide, the degree of conversion to sulfur 93%; the concentration in the exhaust gas is 0.35% by volume; no oxidation and decomposition of methane is observed,

Example 2 Similar to Example 1, but pure oxygen is used as the oxidizing agent. After mixing the source gas with oxygen in a volume of S +

1/2 0 +

0

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five

0

five

0

five

0

five

nom ratio of 1: 0.15 to the reactor serves a mixture of composition, about 6.%: 26.1; Ou 13, COg 1, methane rest, oi 1.0.

The degree of purification from hydrogen sulfide is 98%; 98% sulfur conversion; HgS concentration in the exhaust gas is 0.6 vol.%.

PRI me R 3. The source gas contains,%: 35; CH4 63. After mixing the gas with air in a ratio of 1: 0.83, the mixture of the composition is fed into the reactor, volume%: 19.1; 0 9.6; N2 35.7; SOD 1.1; methane the rest. Other conditions are similar to example 1.

The degree of neutralization from hydrogen sulfide is 98%; the degree of conversion of hydrogen sulfide to sulfur is 98%; oxidation and decomposition of methane is not observed.

An example. The source gas contains, vol.%: CO. 2; CH4 58. After mixing the gas with air in a ratio of 1: 0.95, the mixture of the composition is fed into the reactor, volume%: 20.5; Og. 10.3; N2 38.3; WITH 1,0; methane the rest. Other conditions are similar to example 1.

Degree of neutralization from hydrogen sulphide 99%; sulfur conversion rate of 99%; oxidation and decomposition of methane is not observed.

PRI me R 5. The source gas contains, vol.%:, 5; WITH ,, 2; CH4, 5. After mixing the gas with air in a ratio of 1: 1.18, the mixture of the composition is fed into the reactor,%: 22.8; O 11, N2 2, COg 0.9; methane the rest.

The degree of purification from hydrogen sulfide is 98%; the degree of conversion of hydrogen sulfide to sulfur, 98%; oxidation and decomposition of methane is not observed.

Example 6 The content of the active component in the catalyst (composition 1} 20% by weight. Other conditions are the same as the example. After mixing with the required amount of air, the mixture of the composition is fed into the reactor,% by volume: 22.8; 0. U ,; Ng 2, CH,. 0.9, oi 1.0.

The degree of purification from hydrogen sulfide is 99%; the degree of conversion to sulfur is 99%. No oxidation or decomposition of methane is observed.

Example 7: Similar to example 1, but MgCr204 / o -AHgOe (composition 2) is used as a catalyst.

The content of the active component is 15 wt.%.

The degree of purification of hydrogen sulfide 97 the degree of conversion to sulfur oxidation and decomposition of methane is not observed.

Example It is similar to example 5, but MgCr2 04 D-ACO3 (composition 3) is used as a catalyst.

The degree of purification from hydrogen sulfide is 98%; 98% sulfur conversion; oxidation and decomposition of methane is not observed.

EXAMPLE 9 Analogous to example 5, but twt MgCr O / S-Mlj Oj (composition k) is used as a catalyst.

The degree of purification from hydrogen sulfide is 98%; the conversion rate of HjS to sulfur is 98%; oxidation and decomposition of methane is not observed.

;

08103

 relation 1: 1, (1) “Other conditions. same as in example 1.

The degree of purification from hydrogen sulfide is 87%; H28 conversion rate is 87%. Example 15. The concentration of hydrogen sulfide in the source gas is 70 vol.%. Air is supplied to oxidizing gases in a ratio of 1: 1.67 (tx. 1). The remaining Q conditions are the same as in Example 1. The degree of purification from hydrogen sulfide is the degree of conversion of H28 in the whole of 72%. Example 1b, Analogous to example 5, but for oxidizing hydrogen sulfide 15 a catalyst of composition 1 is used with an active ingredient content of 8%.

The degree of purification from hydrogen sulfide 93%; conversion rate is 93%.

20 Example 17. In a reactor containing 5 g of catalyst (composition 1),

Example 10: Process temperature 350 ° C. Other conditions are similar to example 5.

The degree of purification from hydrogen sulfide is 99%; sulfur conversion rate of 99%; oxidation and conversion of methane is not observed.

Example 11. The volumetric feed rate of the gas mixture to the 6000 iJ reactor. Other conditions are the same as in Example 5.

The degree of purification from hydrogen sulfide is 98%; 98% sulfur conversion; oxidation and decomposition of methane is not observed.

EXAMPLE 12 The source gas contains in its composition dust (silica sand) with an average particle size of 50 microns, a dust concentration of 0.5 wt.%). Other conditions are similar to example 5. The operation time is 100 hours.

The average degree of purification from hydrogen sulfide during operation is 98%; a sulfur conversion rate of 98%; oxidation and decomposition of methane is not observed.

PRI me R 13. Similar to example 12, but the concentration of dust in the gas is 1 wt.% (Corresponds to the maximum concentration of dust in the exhaust gases). Operating time 100 hours. I

The average degree of purification from hydrogen sulfide is 98%; average degree of transformation

at 300 s, a gas mixture of the composition is supplied, 6b.%: H2S 23; Og 12.7; Nj 38; CO. 1, the rest is methane, oL 1.1,

25 3600.

The concentration of SOg in the exhaust gas is 1.8 vol.%; total conversion of N28 to SOa and sulfur 100%; the degree of conversion of NGZ to sulfur is 9.8%.

Example 18. In a reactor containing 5 g of catalyst (composition 1), a gas mixture of the composition, vol.%: H, S 23; 0g. N, 38; CO 1; methane the rest, about 1.2. The remaining conditions are the same as in example 17.

The concentration of SOi in the waste gas is 3.4%; total conversion to sulfur and 80g 100%; HgS conversion rate

sulfur 89%.

Example 19. In a reactor containing 5 g of catalyst (composition 1), at 300. ° C serves a mixture of composition,% vol. 23; N2 38; CO. one; Og 15; methane the rest. About 1.3.

The concentration of SOg in the exhaust gas is 5.3 vol.%; total conversion to sulfur and SOi 100%; 84% sulfur conversion.

The results of the experiments are given in table. 2

The examples show that the proposed method using a catalyst allows in one step to achieve high degrees

40

45

50

whelp N28 to sulfur 98%; oxidation and 55 times the purification from HjS in a fairly widespread methane deposition is not observed. temperature range of 250–350 ° C (i.e. pp ime r I. The concentration of hydrogen sulfide in the source gas is 60 06.%. On

measures 9 and 10), concentrations of hydrogen sulfide 30-50 vol.% (examples 1.3-5) and volumetric rates.

gas oxidation air is supplied to co0

at 300 s, a gas mixture of the composition is supplied, 6b.%: H2S 23; Og 12.7; Nj 38; CO. 1, the rest is methane, oL 1.1,

5 3600.

The concentration of SOg in the exhaust gas is 1.8 vol.%; total conversion of N28 to SOa and sulfur 100%; the degree of conversion of NGZ to sulfur is 9.8%.

Example 18. In a reactor containing 5 g of catalyst (composition 1), a gas mixture of the composition, vol.%: H, S 23; 0g. N, 38; CO 1; methane the rest, about 1.2. The remaining conditions are the same as in example 17.

The concentration of SOi in the waste gas is 3.4%; total conversion to sulfur and 80g 100%; HgS conversion rate

sulfur 89%.

Example 19. In a reactor containing 5 g of catalyst (composition 1), at 300. ° C serves a mixture of composition,%: 23; N2 38; CO. one; Og 15; methane the rest. About 1.3.

The concentration of SOg in the exhaust gas is 5.3 vol.%; total conversion to sulfur and SOi 100%; 84% sulfur conversion.

The results of the experiments are given in table. 2

The examples show that the proposed method using a catalyst allows in one step to achieve high degrees

0

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5 purification from HjS in a fairly wide temperature range of 250-350 C (sizes 9 and 10), hydrogen sulfide concentrations of 30-50 vol.% (Examples 1.3-5) and volumetric rates.

The proposed method can be used to purify hydrocarbon-containing gases at concentrations of hydrogen sulfide in them up to 50 vol.%, and the known method allows to process natural gases with a concentration of hydrogen sulfide up to 25 vol., using five catalytic steps. it necessitates the creation of additional catalytic stages, thus, at a concentration in the source gas of about 50 vol.%, 10 successive reactors will be needed. The multistepness of the known method causes a high metal intensity and complexity of instrumentation of the process. This precludes the creation of mobile stripping gas disposal systems based on this method.

Claims (2)

1. A method for purifying exhaust gas from hydrogen sulphide from wells, including oxidation with oxygen on a catalyst to produce elemental sulfur, characterized in that In order to ensure purification efficiency when the content in gases is 30-50 vol.% of hydrogen, hydrogen, and to simplify the process, magnesium chromite on a carrier — alumina with a content of magnesium chromite of 10–20 wt.%, taken as spherical granules with a strength of 165-520 kg / cm, and the oxidation process is carried out in a fluidized bed of catalyst at 250-350 C. 2. The method according to claim 1, about tl and h and y - y and with the fact that oxygen is taken in the amount of 100-110 o6.% of stoichiometry. Table 1