Utilize reforming gas waste heat continuous production liquid SO
3And 65%SO
3The system of oleum
The present invention relates to a kind of production sulfan (SO
3) and 65% sulphur trioxide (SO
3) system of oleum.
At present, industrial production liquid SO
3And 65%SO
3(dissociating) oleum all adopts 20%SO
3(dissociating) common oleum is a raw material, and through 2-3 placed in-line still pot, with the coal heating, one pot one pot discontinuously SO
3Steam, make liquid SO through condensation
3Or 65%SO
3Sulfuric acid behind the fuming acid, every pot of steaming is put back to system again.Again in pot, add 20%SO later on
3Fuming acid continues to produce.The poor product quality that this method is produced, the device structure complexity, investment is big, and is intermittent operation, and it was both dangerous to need to consume a large amount of bunker coals, and output is low again.In addition, producing in the vitriolic technology with reforming gas, adopting the processing unit of double conversion and double absorption usually, promptly it has two absorption towers, carries out twice absorption with twice reforming gas and produces sulfuric acid.Though this equipment need not consume coal, can't produce pure SO
3And 65%SO
3Fuming acid can't satisfy people's needs.
Purpose of the present invention is exactly to provide a kind of device structure simple in order to address the above problem, invest little, the safe and reliable reforming gas waste heat continuous production liquid SO that utilizes
3And 65%SO
3The system of oleum.
Technical solution of the present invention:
A kind of reforming gas waste heat continuous production liquid SO that utilizes
3And 65%SO
3The system of oleum, it includes 20%SO
3Oleum absorption tower 1 and 98% sulfuric acid absorption tower 2, wherein the outlet on absorption tower 1 links to each other with circulation groove 6-2, the outlet on absorption tower 2 with circulation groove 6-3, link to each other, circulation groove 6-2 and 6-3 are connected by pump (9), comb water cooler 7 connects the spray acid import of 98% sulfuric acid absorption tower 2, and spiral water cooler 8 meets 20%SO
3The spray acid import on oleum absorption tower 1, another outlet that it is characterized in that circulation groove 6-2 links to each other with the liquid-inlet of thin-film evaporator 3 by pump 10, the gas feed of thin-film evaporator 3 connects the reforming gas of being sent here by convertor with certain temperature, and reforming gas is communicated with the pneumatic outlet of thin-film evaporator 3 by valve 11 simultaneously and together meets 20%SO
3The gas feed on oleum absorption tower 1, the liquid exit of thin-film evaporator 3 connects the import of circulation groove 6-2, form the recycle system of thin-film evaporator 3, the evaporation outlet of thin-film evaporator 3 links to each other with the gas feed of condenser 4, the entery and delivery port of condenser 4 connects water coolant, can obtain neat liquid SO at its condensate outlet
3, the pneumatic outlet of condenser 4 meets 65%SO
3The gas feed on oleum absorption tower 5,65%SO
3The pneumatic outlet on oleum absorption tower 5 connects the gas feed of 98% sulfuric acid absorption tower 2 by valve 12, and its liquid exit meets the circulation groove 6-1 of self, and circulation groove 6-1 meets 65%SO by pump 13 and spiral water cooler 14
3The spray acid import on oleum absorption tower 5, circulation groove 6-2 also is communicated with circulation groove 6-1,6-3 by pump 15.
System of the present invention is rationally advanced, and is simple in structure, invests for a short time, both can produce liquid SO separately
3Or 65%SO
3Fuming acid also can while continuous production liquid SO
3And 65%SO
3Fuming acid.Present device utilizes reforming gas used heat to come work, so equipment is durable in use, need not to expend bunker coal, the production cost product low 100% more than than produced in conventional processes per ton, and entire equipment production is being carried out under the air tight condition continuously, and the concentration of medium that is contacted is a scope stably, and equipment is subjected to the corrosion situation very faint, the quality product height is wanted much superior at aspects such as outward appearance and dregginess.
Fig. 1 is the structure principle chart of system of the present invention.
Dotted portion is the part of original sulfuric acid typical production flow process among Fig. 1, and the solid line among Fig. 1 is partly made liquid SO for the present invention
3With 65% free SO
3The environment division that oleum increased.
As Fig. 1, temperature is that (this reformed gas is by SO for 200~290 ℃ reforming gas
3Convertor is sent, and it is about 8% SO
3Gas) at first send into thin-film evaporator 3, this moment is by 200%SO
3The 20% free SO that carry to thin-film evaporator 3 by circulation groove 6-2 and pump 10 on oleum absorption tower 1
3Just by the heat heating evaporation of reforming gas itself, the reforming gas after the heat exchange is sent into 20%SO to oleum
31 relieving haperacidity of oleum absorption tower, SO
3Thin-film evaporator 3 evaporation back liquid are got back to circulation groove 6-2, with 20%SO
3The concentration that oleum absorption tower 1 is sent is higher than 20% free SO
3Oleum is sent into SO after mixing again
3Thin-film evaporator 3 forms circulation.Evaporation at thin-film evaporator 3 exports the SO that obtains
3Vaporised gas is delivered to SO
3Condenser 4 condensations just obtain condensed neat liquid SO from the condensate outlet of condenser 4
3, the SO that does not have condensation to get off
3Gas is delivered to 65%SO again
3Oleum absorption tower 5 absorbs, and sends into circulation acid tank 6-1 after the absorption, and circulation acid tank 6-1 sends into 14 coolings of spiral water cooler by pump 13, and the liquid-inlet of sending absorption tower 5 after the cooling back to is by absorbing SO
3Gas increases concentration, can obtain 65%SO from the outlet of spiral water cooler 14 simultaneously
3The oleum finished product.For guaranteeing that circulation acid tank 6-2 goes here and there acid and regulates, when promptly concentration is high, deliver to circulation groove 6-2, if amount is after a little while, be returned to circulation groove 6-1 from circulation groove 6-2 outlet by pump 15 again, guarantee continuous production.65%SO
3The gas that not having in the oleum absorption tower 5 absorbs is delivered to 98% sulfuric acid absorption tower 2 from its outlet and is absorbed once more and be used for relieving haperacidity.