CN1024524C - Method for operation of claus-apparatus - Google Patents

Abstract

The invention concerns a manner of execution of the procedure according to main patent no.P3843295. In this case it is provided that an exhaust gas containing ammonia is added to the original gas, prior to its introduction into the combustion furnaces.

Description

Method for operation of Claus-apparatus

The present invention relates to a kind of working method of Cross unit, particularly a kind of composition-formed of this method.

In coking industry, utilize Crouse's method to produce sulphur and be widely used.US4 for example, 143,122 have described a kind of circulation cleaning equipment that cleans coke oven gas, equipment is in the front of a clustered aggregates, the latter is by the reactor of decompose nitrogen, refrigeration cycle recovery indirectly, and alkalization washing (extraction element), the claus oven that waste heat boiler is housed and two claus reaction devices are formed.This clustered aggregates is used for producing sulphur in the waste gas from the circulation cleaning equipment of front, produces the bottom heat supply gas of sulfur-bearing hardly and steam simultaneously as its byproduct.Crouse's residual gas then goes back in the reactor front delivery that is used for decompose nitrogen.

This device can only the cycle of treatment washing plant waste gas, as its raw material of determining, and the partial combustion of the decomposition of nitrogen compound and sulphur compound is to carry out in two different equipment, these two equipment configurations air feeder and waste heat boiler.

In the working method of Cross unit of the present invention, make earlier to contain H ₂The unstripped gas partial combustion of S, in a two-stage or multistage claus reaction device, continue reaction then, wherein, in the roasting kiln of the band waste heat boiler of on or two, installing side by side, the flow that depends on the hydrogen sulfide that adds with unstripped gas is realized the prime burning of unstripped gas, after this gas is further handled in an one claus reaction device, and the throughput of this reactor is by the maximum sulphur flow set of expecting.

In described method, be defined in the residual gas that forms behind the claus reaction device and will carry out shortening, the sulfide that all still are contained in the residual gas becomes hydrogen sulfide.Wherein with the heating hydrogen carrier of coal gas as hydrogenation.In addition, also use the hydrogen in the residual gas together, this hydrogen produces in the catalyst layer at roasting kiln when the generation catalytic decomposition of nitrogenize contained in the unstripped gas.Generally speaking, the hydrogen content in the residual gas is not enough to make the complete hydrogenation of contained sulfide, therefore, in the method, introduces heated air and is absolutely necessary as hydrogen carrier.

Therefore, the present invention relates to a kind of composition-formed of described method, on the one hand, can make the shortening of residual gas worthwhile more economically, can solve the environmental protection problem of ammonia-contaminated gas on the other hand simultaneously by this method.

According to the present invention,, can finish above-mentioned task by before entering roasting kiln, sneaking into a kind of ammoniated waste gas in the unstripped gas of back.

The ammonia-contaminated gas that mixes to unstripped gas can be a kind of waste gas from any source, for example is from the steam stripped ammonia vapour mixture that contains of waste water.Depend on its ammonia content, every Nm with raw material gas phase blended exhausted air quantity ³(standard cubic meter) unstripped gas can mix a Nm at most ³Waste gas.The ammonia contained nitride in unstripped gas that is added by this mode carries out catalytic decomposition at the catalyst layer of roasting kiln, has correspondingly improved the amounts of hydrogen that is produced in this way thus.Thereby the amounts of hydrogen of this raising can be used for the residual gas shortening, therefore, and the hydrogen that can corresponding minimizing adds from other source for this purpose, perhaps in case of necessity even can stop fully.

Further specify other details of the inventive method below by means of schema shown in the drawings.

In this schema, enter at pipeline 1 before the burner 2 and 5 of roasting kiln 3 and 6, in unstripped gas, sneak into a kind of ammoniated waste gas through managing 42.If the hydrogen sulfide flow that unstripped gas is brought into greater than the predetermined volumes of burning disconnected 3, will be shunted the gas mixture of a part of unstripped gas and ammonia-contaminated gas by pipe 1, through managing 4 burners 5 of sending into second roasting kiln 6.Supply with required combustion air by pipe 7 and 8 to burner 2 and 5, be used for to burner 2 and the necessary burning gas of 5 supplies, for example coke(oven)gas or partial oxygen gasification by pipe 9 pipes of telling 10 and 11.All be provided with catalyst layer 3a and 6a in the roasting kiln 3 and 6, be used for decomposing nitride that exists in the unstripped gas and the nitrogen of bringing into by waste gas.Catalyst layer 3a here and 6a are equipped with the commercial catalyst that this is suitable for, and they for example contain nickel is catalytic active substance.

The hydrogen that ammonia and all the other nitride catalysts generate when decomposing is stayed in the gas.Through after the roasting kiln 3, the gas of this heat enters waste heat boiler 13 via pipe 12, is 270 ℃ in this gas cooling to temperature, so that then enter collection tube 15 through managing 14, pipe 15 is sent to gas the first step of claus reaction device 16.If started second roasting kiln 6 equally, the gas shunting that handle the there is extracted out by pipe 17, correspondingly cooling in affiliated waste heat boiler 18, and this is after manage the 19 same collection tubes 15 of introducing, like this, two stock streams of gas lump together and send into claus reaction device 16.Gas is extracted out by the first step of claus reaction device 16 through managing 20, and arrives first flue of waste heat boilers 22 through interchanger 21, and being cooled to temperature at this is 154 ℃.Then, through managing 23 gas sent into the second stage of claus reaction device 16.Wherein, obtaining a little in the interchanger 21 that gas connects betwixt reheats.Gas is drawn by claus reaction device 16 through managing 24 again, is sent to second flue of waste heat boiler 122, and being cooled to temperature again at this is 154 ℃.Because most sulphur are removed from the gas of waste heat boiler 22 back, so this gas that repeatedly is also referred to as Crouse's residual gas only contains a small amount of unconverted H ₂S and SO ₂Because these impurity, this residual gas can't directly enter atmosphere.Thereby, at first it is sent into interchanger 26 through managing 25, arrive hydrogenation reactors 29 through managing 27 then, wherein, be heated to about 280 ℃ in the well heater 28 that gas connects earlier betwixt.In hydrogenation reactor 29, all sulfide that are contained in the residual gas all become hydrogen sulfide through shortening.Wherein, the hydrogen carrier that at first is used for hydrogenation with the contained hydrogen conduct of residual gas itself.Because the present invention sneaks into unstripped gas with ammonia-contaminated gas, has correspondingly improved the hydrogen content in the residual gas.If so also deficiency is so that the complete hydrogenation of all sulfide that residual gas still exists, can add other hydrogen-containing gas, for example combustion gas to hydrogen reactor 29 through managing 9.For the shortening of sulfide, use commercially available hydrogenation catalyst here, they for example contain that nickel is activeconstituents.Residual gas behind the hydrogenation is extracted out by hydrogenator through managing 30.As previously mentioned, because this residual gas only contains H ₂S is as sulfur component, and available one goes on foot H ₂The S washing continues to handle to it.If Cross unit and gasification or the coupling of coal tar equipment, the raw gas that this residual gas for example can be produced with the there is at H ₂Mix mutually before the S washing step.

The isolating sulphur of gas cooling time institute is extracted out through managing 31,32,33 and 34 in waste heat boiler 13,18 and 22, and each manifold goes into to collect house steward 35, by pipe 35 sulphur is sent to further processing treatment.Pipe 36 is used for to waste heat boiler 22 provides boiler water storage, and the steam that the there produces is then extracted out by pipe 37.Waste heat boiler 13 is supplied with necessary boiler water storage by pipe 38.Tell arm 39 by this pipe, supply with boiler water storage to waste heat boiler 18.Extract the steam that produces out by managing 40 and 41 in waste heat boiler 13 and 18, the steam of wherein managing in 41 merges with the vapor phase of managing in 40.

Illustrate that with embodiment the mode of operation of the inventive method contains 53%(Vol below) H ₂The unstripped gas of S is with 1210Nm ³The flow of/h enters technology by pipe 1.To sneak into flow to this air-flow be 240Nm through managing 42 ³/ h contains 18%(Vol) NH ₃Waste gas.It is very high to handle in the residual gas that this mixed gas forms hydrogen richness under the condition of having stated in front then, so that only need import only 59Nm to hydrogenator 29 through managing 9 ³Combustion gas.Compare with preceding method, saved 79% expense during the residual gas hydrogenation.Solved the problem of environmental pollution of the ammonia-contaminated gas that adds simultaneously.

Claims (2)

1, a kind of working method of Cross unit wherein makes earlier to contain H ₂The unstripped gas of S is in the roasting kiln of one or two band waste heat boiler of installing side by side, the flow that depends on the hydrogen sulfide that adds with unstripped gas is realized the prime burning of unstripped gas, it is characterized in that: before entering roasting kiln, in unstripped gas, sneak into a kind of ammoniated waste gas, after the burning, gas is further handled in an independent claus reaction device.

2, the described method of claim 1 is characterized in that, mostly is every Nm most with the amount of the ammonia-contaminated gas of original mixed gases ³Raw material mixes 1Nm ³Waste gas.

Images