The method of rich hydrocarbon industrial tail gas combined production of methanol, natural gas used for automobile and synthetic ammonia
Technical field
The present invention relates to a kind of method of utilizing rich hydrocarbon industrial tail gas production methyl alcohol, natural gas used for automobile and synthetic ammonia, being specifically related to a kind of is the method that raw material does not have conversion combined production of methanol, natural gas used for automobile and synthetic ammonia with rich hydrocarbon industrial tail gas such as coke-oven gas, calcium carbide furnace gas.
Background technology
The main raw material of synthesizing methanol, ammonia has Sweet natural gas and coal.Unstripped gas so that Sweet natural gas and coal make must could obtain qualified synthetic gas or hydrogen through technological processs such as conversion, separation.Technical process is longer, and natural resources is not fully used.The waste gas of at present industrial various hydrogeneous, carbon monoxide such as coke-oven gas, calcium carbide furnace gas etc., yellow phosphorus furnace gas are more and more.China has coke-oven gas, the above carbon monoxide of 6,000,000,000 standard cubic meter of nearly 40,000,000,000 standard cubic meter not to obtain utilizing and discharging in vain every year.
Utilize coke-oven gas synthetic ammonia, generally adopt methane portion oxidation or steam reforming technology to produce hydrogen and carbon monoxide, carry out middle temperature, low temperature shift, decarburization and methanation operation then successively and obtain qualified synthetic ammonia feedstock.During synthesizing methanol, also must be through operations such as conversion, conversion, benefit charcoals, to obtain acceptable material gas.This type of technical process is long, energy consumption is high, investment is high, unstripped gas active principle utilization ratio is low.
The utilization of calcium carbide furnace gas has two kinds of heat energy utilization and chemical utilizations usually, and promptly act as a fuel gas and industrial chemicals use.At present, China most of calcium carbide manufacturing enterprise all recycles calcium carbide furnace gas, but with the direct burning and exhausting of the form of igniting the torch, has promptly wasted a large amount of energy, again environment has been caused severe contamination.Only there is small part enterprise to reclaim, also only is used for producing steam or limestone kiln, the use that acts as a fuel, utilization ratio is low, comprehensive benefit is poor.In chemical utilization, at first carry out the purification of carbon monoxide, carbon monoxide after the purification is mainly used in produces high pure metal (nickel, tungsten, platinum etc.), sponge iron, polycrystalline state diamond film and some special steel, is used as the reductive agent of iron in the steel-making blast furnace etc., and added value is lower.
Summary of the invention
Technical problem to be solved by this invention is at above-mentioned deficiency of the prior art, the method for rich hydrocarbon industrial tail gas combined production of methanol, natural gas used for automobile and the synthetic ammonia that provide that a technical process is short, energy consumption is low, less investment and unstripped gas active principle utilization ratio is high.
For solving the problems of the technologies described above, the technical solution used in the present invention is: the method for the hydrocarbon industrial tail gas combined production of methanol of a kind of richness, natural gas used for automobile and synthetic ammonia is characterized in that this method may further comprise the steps:
(a) coke-oven gas and the calcium carbide furnace gas after will purifying, directly enter the methyl alcohol synthesizer, under the effect of methanol synthesis catalyst, make carbon monoxide, carbonic acid gas and H-H reaction in the gas generate methyl alcohol, reacted release gas is without circulation or small amount of recycled, and the volume percent of described coke-oven gas and calcium carbide furnace gas is 15: 1-3;
(b) with the release gas behind the synthesizing methanol in the step (a), enter methanator, under the effect of methanation catalyst, react, make remaining hydrogen in the gas and carbon monoxide, the carbonic acid gas generation methane that reacts, reacted gas carries out the transformation fractionation by adsorption through the transformation adsorption separation device, and isolated methane is as natural gas used for automobile; Hydrogen that the transformation fractionation by adsorption goes out and nitrogen carry out ammonia synthesis under the effect of synthetic ammonia catalyst, hydrogen unnecessary after the ammonia synthesis is pure hydrogen through the transformation fractionation by adsorption.
The unstripped gas that technical solution of the present invention adopts is coke-oven gas and calcium carbide furnace gas." two gas head " scheme fully combines the characteristics of the rich hydrogen of coke-oven gas, the many carbon of calcium carbide furnace gas, not only produces multiple Chemicals, has improved the economic benefit of whole process and the utilization ratio of industrial tail gas active principle, and realized exempting from CH
4Transform, exempt from the CO conversion, no air separation facility has reduced the complicacy of technology, the saving energy consumption, and resource obtains maximum using.
Coke-oven gas mainly refers to the by-product gas of process of coking, generally mainly consisting of of coke-oven gas: carbon monoxide 5.5~7.0%; Carbonic acid gas 1.2~2.5%; Hydrogen 54~59%; Methane 23~28%; Nitrogen 3~5%; Oxygen 0.3~0.7%.When calcium carbide furnace gas is meant employing closed calcium carbide furnace production calcium carbide, in process of production, the industrial gaseous waste of generation.Its classical group becomes: carbon monoxide 75~85%; Carbonic acid gas 1~3%; Hydrogen 3~10%; Methane 0.2~2%; Nitrogen 3~8%; About oxygen 0.5%.Carbon monoxide and carbonic acid gas are relatively low owing to hydrogen richness in the coke-oven gas is higher, during therefore with its synthesizing methanol, must methane conversion wherein be carbon monoxide, and, hydrogen charcoal ratio is adjusted to certain proportion, to satisfy the technical requirements of catalst for synthesis of methanol by means such as benefit charcoals, therefore technical process is longer, owing to must methane conversion wherein be carbon monoxide, be provided with conversion and air separation facility, its investment is bigger.
Technical solution of the present invention adopts coke-oven gas and calcium carbide furnace gas to be used, improving the hydrogen charcoal ratio in the gas mixture, thereby satisfy the technical requirements of methanol synthesis catalyst, and the gas behind the synthesizing methanol directly enters methanator, reduce the gas circulation amount, and reduced investment.
The present invention compared with prior art has the following advantages:
1. make gas composition and effectively energy step application, reduce unstripped gas and energy expenditure.
2. exempt from CH
4Transform, exempt from the CO conversion, no air separation facility has reduced the complicacy of technology.
3. opened up a new way for the comprehensive utilization of rich hydrocarbon industrial tail gas such as coke-oven gas, calcium carbide furnace gas.
4. reduced emission amount of carbon dioxide.
5. investment cost is low.
Below by embodiment, technical scheme of the present invention is described in further detail.
Embodiment
Methanol synthesis catalyst in following examples (as C306, XNC-98, NC307 and LC308), methanation catalyst (as 0804-2, J103H and J111, JRE and RHM-266), synthetic ammonia catalyst (as A110-1 (H)) all adopt domestic sophisticated commercial catalysts at present.Under the processing condition of embodiment, the methanol reactor bed temperature is in 210~280 ℃ of scopes; The methanator bed temperature is in 270~500 ℃ of scopes; The ammonia synthesis reactor bed temperature is in 380~550 ℃ of scopes.
Embodiment 1
Coke-oven gas adopts existing mature technology, after wet purification, removes wherein prussiate and partial vulcanization thing, and residue sulfide adopts dry purification process that it is removed to 0.1 * 10
-6(v/v) below; Calcium carbide furnace gas adopts the prior art dedusting, remove prussiate after, wherein acetylene is removed to 5 * 10
-6(v/v) below.Come coke-oven gas and calcium carbide furnace gas behind the self-purification, by after 15: 1 mixed, carbon monoxide 10.85%; Carbonic acid gas 1.86%; Hydrogen 53.38%; Methane 23.98%; Nitrogen 4.09%; Oxygen 0.40% is with 10000h
-1After air speed is passed through methanol reactor, carbon monoxide 4.93%; Carbonic acid gas 0.84%; Hydrogen 51.64%; Methane 36.38%; Nitrogen 6.20%.Reacted gas is with 3000h
-1Air speed is by behind the methanator, carbon monoxide and total carbon dioxide content are less than 0.2%, hydrogen 42.56%, methane 49.42%, nitrogen 7.67%, again after the transformation adsorption separation device carries out the transformation fractionation by adsorption, can obtain methane content greater than 95% natural gas used for automobile and hydrogen nitrogen mixed gas.The residual hydrogen nitrogen mixed gas enters ammonia synthesis reactor, carries out ammonia synthesis under the effect of synthetic ammonia catalyst, and hydrogen unnecessary after the ammonia synthesis is pure hydrogen through the transformation fractionation by adsorption.
Embodiment 2
Coke-oven gas adopts existing mature technology, after wet purification, removes wherein prussiate and partial vulcanization thing, and residue sulfide adopts dry purification process that it is removed to 0.1 * 10
-6(v/v) below; Calcium carbide furnace gas adopts the prior art dedusting, remove prussiate after, wherein acetylene is removed to 5 * 10
-6(v/v) below.Come coke-oven gas and calcium carbide furnace gas behind the self-purification, by after 15: 2 mixed, carbon monoxide 14.93%; Carbonic acid gas 1.87%; Hydrogen 50.62%; Methane 22.63%; Nitrogen 4.18%; Oxygen 0.41% is with 12000h
-1After air speed is passed through methanol reactor, carbon monoxide 7.88%; Carbonic acid gas 0.99%; Hydrogen 43.95%; Methane 39.83%; Nitrogen 7.36%.Reacted gas is with 4000h
-1Air speed is by behind the methanator, carbon monoxide and total carbon dioxide content are less than 0.2%, hydrogen 24.73%, methane 64.35%, nitrogen 10.43%, again after the transformation adsorption separation device carries out the transformation fractionation by adsorption, can obtain methane content greater than 95% natural gas used for automobile and hydrogen nitrogen mixed gas.The residual hydrogen nitrogen mixed gas enters ammonia synthesis reactor, carries out ammonia synthesis under the effect of synthetic ammonia catalyst, and hydrogen unnecessary after the ammonia synthesis is pure hydrogen through the transformation fractionation by adsorption.
Embodiment 3
Coke-oven gas adopts existing mature technology, after wet purification, removes wherein prussiate and partial vulcanization thing, and residue sulfide adopts dry purification process that it is removed to 0.1 * 10
-6(v/v) below; Calcium carbide furnace gas adopts the prior art dedusting, remove prussiate after, wherein acetylene is removed to 5 * 10
-6(v/v) below.Come coke-oven gas and calcium carbide furnace gas behind the self-purification, by after 15: 3 mixed, carbon monoxide 18.54%; Carbonic acid gas 1.88%; Hydrogen 48.17%; Methane 21.43%; Nitrogen 4.25%; Oxygen 0.42% is with 10000h
-1After air speed is passed through methanol reactor, carbon monoxide 8.46%; Carbonic acid gas 0.87%; Hydrogen 30.64%; Methane 49.93%; Nitrogen 9.90%.Reacted gas is with 4000h
-1Air speed is by behind the methanator, carbon monoxide and total carbon dioxide content are less than 0.2%, hydrogen 2.95%, methane 84.30%, nitrogen 12.28%, again after the transformation adsorption separation device carries out the transformation fractionation by adsorption, can obtain methane content greater than 95% natural gas used for automobile and hydrogen nitrogen mixed gas.The residual hydrogen nitrogen mixed gas enters ammonia synthesis reactor, carries out ammonia synthesis under the effect of synthetic ammonia catalyst, and hydrogen unnecessary after the ammonia synthesis is pure hydrogen through the transformation fractionation by adsorption.
For 1,000,000 tons of/year coke and 180,000 tons of/year calcium carbide enterprises, can produce 4.65 hundred million m every year
3Coke-oven gas and 0.81 hundred million m
3Calcium carbide furnace gas.Adopt the technical program, preresearch estimates can be produced 8.6 ten thousand tons of methyl alcohol, 1.5 hundred million m every year
3Natural gas used for automobile and 0.7 ten thousand tons of synthetic ammonia, 500,000,000 yuan of the output values reduce CO
2Discharge 210,000 tons.
The above; it only is preferred embodiment of the present invention; be not that the present invention is imposed any restrictions, everyly any simple modification that above embodiment did, change and equivalence changed, all still belong in the protection domain of technical solution of the present invention according to the technology of the present invention essence.