Background technology
All need to spray paint application in the industrial processes such as container, automobile, furniture, machine-building, need to use a large amount of organic solvent (Tianna solution etc.) in spraying lacquer process, these solvents are to discharge with the waste gas form.The processing method of current large-scale manufacturing lacquer spraying waste gas both domestic and external generally adopts methods such as burning disposal, concentrated catalytic combustion, the operating cost of incineration treatment method is very high, to expend a large amount of fuel simultaneously, make a lot of enterprises to bear, and solvent can not reclaim, and resource can not reuse.
At present, domestic other industry can be reclaimed lower boiling organic exhaust gas.The flow chart of the recovery technology that adopts as shown in Figure 1, the waste gas of production line carries out preliminary treatment through filter 10 and cooler 20 and removes the harmful substance to active carbon such as dust in the waste gas, after cooling off and going dust to handle, enter adsorption tanks 40 by blower fan 30, organic exhaust gas is purified by charcoal absorption, clean air after the purification directly discharges, the organic solvent that desorption comes out and the mist of steam enter separator after condenser 50 is condensed to normal temperature, according to solvent properties, water-soluble solvent is adopted rectifying, methods such as extraction are separated, to water-insoluble solvent, entering oil water separator 60 separates, the solvent of separating can further be handled or directly be recycled in the solvent tank 70, and the waste water of separating then directly discharges or enters the waste water processing station and further handle.
And the organic exhaust gas that picture spraying lacquer is produced, because the used organic solvent of its production process very mixes, boiling point is arranged below 110 ℃, as: benzene, toluene, n-butanol, cyclohexane, gasoline etc., boiling point is also arranged from 110 ℃ to 290 ℃, as dimethylbenzene, trimethylbenzene, durene, ethylene glycol monoethyl ether, ethylene glycol ether acetate, aromatic hydrocarbon solvent is (as SOLVESSO100#, 150#, the 200# solvent naphtha) etc., and be the organic solvent of multiple mixing, high boiling organic solvent, as trimethylbenzene, durene, ethylene glycol monoethyl ether, ethylene glycol ether acetate, aromatic hydrocarbon solvent is (as SOLVESSO100#, 150#, the 200# solvent naphtha) etc., with being difficult to desorption after traditional charcoal absorption technology absorption, simultaneously, spraying lacquer waste gas mixes the organic solvent of multifrequency nature difference great disparity, so, to when administering waste gas, organic solvent be reclaimed,, all do not had successful story though there is the people to do the trial that this recovery is administered in the past.
The inventor is at present situation, this is studied, accomplished in such waste gas of purification treatment, reclaim valuable resource---organic solvent, recovered solvent can be reused, and has reduced the consumption of fuel again, has both reached the cleaner production purpose, reach resource circulation utilization again, meet the requirement of sustainable development.
Therefore, the present invention will fill up such waste gas purification and reclaim the blank of administering.
Summary of the invention
The present invention aims to provide a kind of method for cleaning, recovering and treating painted lacquer exhaust organic gas and device; the recycling that contains various boiling points, characteristic differs greatly, ratio differs organic exhaust gas that is applicable to that spraying lacquer produced in producing; when such waste gas is administered; the resource of preciousness is reclaimed; reduce the consumption of the energy simultaneously, realized the purpose of energy-saving and emission-reduction, protection environment.
In order to reach above-mentioned purpose, technical scheme of the present invention is:
Method for cleaning, recovering and treating painted lacquer exhaust organic gas, carry out as follows: the organic exhaust gas that (1) painting line comes out, after collecting or coming out from paint spray booth, the drying room that sprays paint, dust, coating cloud through in the filtration treatment removal waste gas adopt cooling means with the high boiling organic solvent composition condensation of boiling point greater than 110 ℃; (2) utilize high boiling solvent to absorb recover again and reclaim the high boiling organic solvent of condensation; (3) through the residue organic exhaust gas after above condensation, the recovery, send into the adsorption tanks that adopt compound carbon bed structure, the not recoverable organic solvent composition of the prior process in the waste gas is adsorbed, waste gas is through adsorption tanks absorption purification later, discharging; (4) adopt the steam desorption method, the organic solvent desorption that adsorption tanks are adsorbed comes out; (5) solvent vapour behind the desorption and steam are become liquid after condensation; (6) with condensed mixing material with oil water separator with organic solvent and moisture from, the organic solvent of separating can be reused, the waste water otherwise processed of separating.
In above-mentioned (4) step, the steam that is used for desorption heats alternating temperature through steam heater earlier, sends into adsorption tanks again.
The cleaning, recovering and treating painted lacquer exhaust organic gas device, mainly comprise filter, can be with the cooler of boiling point greater than 110 ℃ high boiling organic solvent composition condensation, high boiling solvent absorbs recover, blower fan, the adsorption tanks of compound carbon bed structure, condenser and oil water separator, the import of filter is connected with the organic exhaust gas pipeline, outlet is connected to the air inlet of cooler, the gas outlet of cooler is connected to the air intake that high boiling solvent absorbs recover, high boiling solvent absorbs recover and has the outlet of the liquid of recovery, the gas outlet of high boiling solvent absorption recover is connected to the inlet of blower fan, the outlet of blower fan is connected to the air inlet of adsorption tanks, the gas outlet of adsorption tanks communicates with atmosphere, the desorption liquid inlet of adsorption tanks is connected with the steam pipeline, the desorption liquid outlet of adsorption tanks is connected to the inlet of condenser, the outlet of condenser is connected to the inlet of oil water separator, and oil water separator has a wastewater outlet and an organic solvent outlet.
Adsorption tanks in parallel more than two are arranged in the said apparatus.
Three above adsorption tanks are arranged in the said apparatus, adopt the mode in parallel again of grouping series connection earlier to be connected in the device.
Filler in the above-mentioned filter adopts fiber filter material.
Above-mentioned cooler is a water cooler.
It is that ripple silk net filler, metal are piled up one or more the combination in filler and the ceramic packing that above-mentioned high boiling solvent absorbs filler in the recover.
Filler in the above-mentioned high boiling solvent absorption recover is the skewed high boiling solvent that is placed on and absorbs in the recover, the bottom incline of corresponding filler offers air intake on the sidewall of high boiling solvent absorption recover, the bottom incline that high boiling solvent absorbs the corresponding filler in bottom of recover offers downward recovery liquid outlet, and the top incline of corresponding filler offers the gas outlet on the sidewall of high boiling solvent absorption recover.
The horizontal high boiling solvent that is placed on of filler that above-mentioned high boiling solvent absorbs in the recover absorbs in the recover, high boiling solvent absorb corresponding filler on the sidewall of recover below offer air intake, offer downward recovery liquid outlet below the corresponding filler in bottom of high boiling solvent absorption recover, offer the gas outlet above the corresponding filler in top of high boiling solvent absorption recover.
Above-mentioned high boiling solvent absorbs in the recover shower nozzle that can spray liquid to filler is installed.
The number of above-mentioned oil water separator is at least one.
After adopting such scheme, the concrete technical process of the present invention can be such: from collect waste gas that organic exhaust gas pipeline (or paint spray booth, drying room) comes out through the filter filtration treatment after, enter the cooler cooling condensation, cooled waste gas absorbs recover through high boiling solvent, reclaimed the high boiling organic solvent in the waste gas, send into the adsorption tanks of one group of compound carbon bed structure again by high pressure positive blower, organic exhaust gas is through compound charcoal bed the time, the adsorbing medium active carbon carries out adsorption cleaning to organic exhaust gas, and the air that purified directly discharges; When compound charcoal bed reached capacity after the process absorption of certain hour, control system was cut off waste gas automatically and is entered adsorption tanks, fed steam or carried out desorption and regeneration through the steam that steam heater is heated; Compound charcoal bed after the regeneration drops into absorption again, and second compound charcoal bed enters desorption and regeneration, and one group of compound charcoal bed is desorption in turn one by one, and circulation is carried out; Organic solvent that desorption comes out and steam enter oil-water automatic segregator and separate after condenser is cooled to normal temperature, and the solvent of separating can utilize again, separate the waste water otherwise processed.The on-condensible gas that condenser comes out can also be sent in the adsorption tanks by blower fan once more and adsorb.
The present invention can adopt the Automatic Control technology, and the man-machine interface operation can show the working condition with monitoring system in real time; At different production status, necessary automatically controlled security protection and reliable interlock protection are set, guarantee the safe and reliable operation of retracting device.
By such scheme as can be seen; the present invention on the basis of existing technology; before entering adsorption tanks through the waste gas after filtering; absorb recover by a high boiling solvent earlier; reclaim the organic solvent of condensation; stop the high boiling organic solvent in the organic exhaust gas to enter adsorption tanks; overcome high boiling organic solvent in the traditional handicraft is difficult to desorption in adsorption tanks shortcoming; under the situation that does not increase energy consumption; the resource of preciousness is reclaimed; reduce secondary pollution, can reuse recovered solvent simultaneously, reduced the consumption of the energy; being applicable to the various boiling points that contain that produced in the production of spraying paint; characteristic differs greatly; the recycling of the organic exhaust gas that ratio differs; both reach the purpose of cleaner production, realized the resource circulation utilization again, realized energy-saving and emission-reduction; the purpose of protection environment.
The specific embodiment
Below in conjunction with accompanying drawing the present invention is described in detail.
As shown in Figure 2, be the flow chart of method for cleaning, recovering and treating painted lacquer exhaust organic gas of the present invention, concrete steps are as follows:
(1) organic exhaust gas that comes out of painting line, after collecting or coming out from paint spray booth, the drying room that sprays paint, carry out filtration treatment through filter 1, after the harmful substances to active carbon such as the most of dust in the removal waste gas, coating cloud, again by cooler 2, with the condensation of the high boiling organic solvent composition of part in the organic exhaust gas, as: dimethylbenzene, trimethylbenzene, durene, ethylene glycol monoethyl ether, ethylene glycol ether acetate, aromatic hydrocarbon solvent boiling points such as (as SOLVESSO100#, 150#, 200# solvent naphthas) are higher than 110 ℃ organic solvent composition;
(2) organic exhaust gas after going dust and cooling processing enters high boiling solvent and absorbs recover 3, reclaims the high boiling organic solvent of condensation by it;
(3) through the residue organic exhaust gas after above step condenses, the recovery, send into adsorption tanks 5 by blower fan 4, these adsorption tanks 5 adopt compound carbon bed structure, it act as in the absorption organic exhaust gas at the not recoverable organic solvent composition of aforementioned process, organic exhaust gas is after adsorption tanks 5 absorption, be purified processing, reached the improvement purpose, can directly discharge by exhaust duct 9;
(4) adopt the steam desorption method, steam is fed in the adsorption tanks 5, so that organic solvent desorption adsorbed in the adsorption tanks 5 is come out, also can be with steam earlier through steam heater 6, it is heated alternating temperature after, send into adsorption tanks 5 again, feed adsorption tanks 5 with vapor form, can full and uniformly be full of the inner space of adsorption tanks 5,, improve solvent recovering rate the abundant desorption of organic solvent of absorption in the adsorption tanks 5;
(5) solvent vapour behind the desorption and steam enter condenser 7, become liquid after condensation;
(6) condensed mixing material is fed oil water separator 8, with organic solvent and moisture from, the organic solvent of separating can be reused, and the direct discharging of waste water of separating or enter the waste water processing station and further handle; And enter adsorption tanks 5 absorption (not shown) by blower fan 4 once more by the on-condensible gas that condenser 7 comes out.
As shown in Figure 3, be that the present invention sprays the artwork that the lacquer organic exhaust gas reclaims the embodiment one of controlling device, comprise that mainly filter 1, cooler 2, high boiling solvent absorb adsorption tanks 5, condenser 7 and the oil water separator 8 of recover 3, blower fan 4, at least one compound carbon bed structure.
The import of filter 1 is connected with the organic exhaust gas pipeline, the organic exhaust gas that painting line comes out, after collecting or coming out from paint spray booth, the drying room that sprays paint, enter filter 1 by the organic exhaust gas pipeline, carry out filtration treatment, filler in the filter 1 adopts fiber filter material, after the harmful substances to active carbon such as the most of dust in the removal waste gas, coating cloud, is entered the air inlet of continuous cooler 2 again by the outlet of filter 1.
In the present embodiment, cooler 2 adopts water cooler, it mainly acts on is with the condensation of the high boiling organic solvent composition of part in the organic exhaust gas, as: dimethylbenzene, trimethylbenzene, durene, ethylene glycol monoethyl ether, ethylene glycol ether acetate, aromatic hydrocarbon solvent boiling points such as (as SOLVESSO100#, 150#, 200#) are higher than 110 ℃ organic solvent composition.Certainly, also can adopt other cooler herein,, not exceed with present embodiment as aerial cooler etc. with identical effect.
Organic exhaust gas after going dust and cooling processing, gas outlet by cooler 2 enters the air intake that high boiling solvent absorbs recover 3, to reclaim the high boiling organic solvent of condensation, prevent that the high boiling organic solvent that mixes in the organic exhaust gas from entering adsorption tanks 5 thereafter, overcome high boiling organic solvent in the traditional handicraft and enter the shortcoming that is difficult to desorption behind the adsorption tanks 5, the resource of preciousness is reclaimed, reduced secondary pollution, can reuse recovered solvent simultaneously, reduce the consumption of the energy.
In the present invention, the concrete structure that high boiling solvent absorbs recover 3 can have the different forms of expression, can be as shown in Figure 6, filler 32 is housed in casing 31, filler 32 is skewed and is placed in the casing 31, the bottom incline of corresponding filler 32 offers air intake 301 on the sidewall of high boiling solvent absorption recover 3, the bottom incline that high boiling solvent absorbs the corresponding filler 32 in bottom of recover 3 offers downward recovery liquid outlet 302, and the top incline of corresponding filler 32 offers gas outlet 303 on the sidewall of high boiling solvent absorption recover 3.The concrete structure of this high boiling solvent absorption recover 3 also can be as shown in Figure 7, the filler 32 horizontal high boiling solvents that are placed on absorb in the casing 31 of recover 3, high boiling solvent absorb corresponding filler 32 on the sidewall of recover 3 below offer air intake 301, offer downward recovery liquid outlet 302 below the corresponding filler 32 in bottom of high boiling solvent absorption recover 3, offer gas outlet 303 above the corresponding filler 32 in top of high boiling solvent absorption recover 3.Wherein, the fillers 32 in the casing 31 are piled up filler for ripple silk net filler or metal, also can be ceramic packings, or ripple silk net filler, metal are piled up filler and several combination of ceramic packing.When practical application, organic exhaust gas is entered by the air intake 301 that high boiling solvent absorbs recover 3, filter by the high boiling solvent in 32 pairs of organic exhaust gas of filler and to hold back, tackle the solvent of condensation, and utilize filler 32 to absorb uncooled high boiling organic solvent molecule through soaking into, agglomeration liquid, flow out by reclaiming liquid outlet 302 then, reclaim, reach the purpose that reclaims this partial solvent, and other composition enters adsorption tanks 5 still by filler 32 by gas outlet 303 in the organic exhaust gas.
Certainly this high boiling solvent absorbs recover 3 also can other structure performances; all ripple silk net filler, metals of can utilizing are piled up one or more combination in filler and the ceramic packing; tackle the solvent of condensation; and utilize filler to absorb uncooled high boiling organic solvent molecule through soaking into; agglomeration liquid; reach the purpose that reclaims this partial solvent, all fall within protection scope of the present invention.
For improving the rate of recovery to high boiling organic solvent, also can absorb shower nozzle 33 is housed in the recover 3 at high boiling solvent, when containing the bigger solvent of viscosity such as aromatic hydrocarbon solvent (as SOLVESSO100#, 150#, 200# solvent naphtha), trimethylbenzene, durene in the waste gas, take to wash to get off to be reclaimed, avoid filler 32 to stop up with the solvent liquid that the method that sprays will be collected on the filler 32.Further, also can on filler 32, add the spray absorption liquid, utilize the principle on chemical industry absorption tower, the high boiling solvent in the organic exhaust gas is absorbed, holds back and reclaims according to the solvent properties in the different waste gas.
Because composition, the ratio of different paint and the different solvent that manufacturer adopted have nothing in common with each other, so this high boiling solvent absorbs the kind of filler 32 in the recover 3, the kind whether shower nozzle 33 and hydrojet are installed is chosen and can be done necessary the adjustment according to different situations.
The gas outlet 303 that high boiling solvent absorbs recover 3 is connected to the inlet of blower fan 4, absorbs residue organic exhaust gas after recover 3 reclaims through high boiling solvent, is sent into the air inlet of adsorption tanks 5 by the outlet of blower fan 4.
Offer the desorption liquid inlet on the adsorption tanks 5, be connected with the steam pipeline, the water supply steam enters, and by steam being fed in the adsorption tanks 5, organic solvent desorption adsorbed in the adsorption tanks 5 is come out.Adsorption tanks 5 adopt compound carbon bed structure, can use the patent No. to be the adsorption tanks described in the ZL200620063193.6, have adsorption tanks 5 among the present invention at least, the concrete number of adsorption tanks 5 and connected mode are according to actual needs and design and decide, in general be formed in parallel by the adsorption tanks 5 of two compound carbon bed structures at least, as in the present embodiment, adsorption tanks 5 are that the adsorption tanks 5 of three compound carbon bed structures compose in parallel, adopt parallel way, can realize that many branch roads adsorb organic exhaust gas simultaneously, improve adsorption efficiency, also can use control valve 10 control organic exhaust gas to enter the passage of adsorption tanks 5 simultaneously, each parallel branch is taken turns to operate, as in the present embodiment, compound charcoal bed in first adsorption tanks 5 is after absorption after a while, will reach capacity, at this moment control valve 10 can cut off the passage that organic exhaust gas enters these adsorption tanks 5 automatically, feed steam then, organic solvent to absorption in these adsorption tanks 5 carries out desorption and regeneration, adsorption tanks 5 after the regeneration drop into absorption again, cut off organic exhaust gas then and enter the passage of second adsorption tanks 5, second compound charcoal bed that reaches the full adsorption tanks 5 that close entered desorption and regeneration, so, one group of compound charcoal bed is desorption in turn one by one, and circulation is carried out; Also can be by the adsorption tanks 5 of compound carbon bed structure more than three, adopt the mode in parallel again of series connection earlier to connect, such as using four adsorption tanks 5, earlier adsorption tanks 5 are connected in twos, and then with two series arm parallel connections, earlier organic exhaust gas is fed series arm, help organic exhaust gas is further adsorbed, improve adsorption effect.
The gas outlet of adsorption tanks 5 communicates with atmosphere, after organic exhaust gas is sent into adsorption tanks 5 by blower fan 4, in the adsorbing medium charcoal absorption organic exhaust gas in the adsorption tanks 5 at the not recoverable organic solvent composition of aforementioned process, organic exhaust gas is carried out adsorption cleaning, and the air that purified can directly be disposed in the atmosphere by exhaust duct 9 by the gas outlet.
The desorption liquid outlet of adsorption tanks 5 is connected to the inlet of condenser 7, and the organic solvent steam and the steam that are come out by adsorption tanks 5 desorptions enter the condenser 7 that is attached thereto, and become liquid after condensation.
The outlet of condenser 7 is provided with a plurality of by-pass valve (not shown), correspondingly also be provided with one or more oil water separators 8, in embodiment one, owing to adopt isothermal desorption method desorption, therefore can only use an oil water separator 8, this separator is similar to the described separator of patent ZL200620063193.6.Condensed mixing material is entered the inlet of oil water separator 8 by condenser 7, organic solvent is separated with water, this oil water separator 8 has a wastewater outlet 801 and an organic solvent outlet 802, the solvent of separating can export 802 by organic solvent and flow out, reclaim, again utilize, and the waste water of separating is directly discharged or is entered the waste water processing station and further handles by wastewater outlet 801, and enters adsorption tanks 5 absorption (drawing among the figure) by blower fan 4 once more by the on-condensible gas that condenser 7 comes out.And in embodiment two,, therefore a plurality of oil water separators 8 need be set owing to adopt the alternating temperature desorption, be used for the solvent of desorption under the different period condition of different temperatures is branched to different solvent species separators, to guarantee to reclaim the different kinds of liquid solvents product.
As shown in Figure 4, process schematic representation for another preferred embodiment of the present invention, desorption reclaims in order to make adsorption tanks 5 adsorbed organic solvents can access to greatest extent, one steam heater 6 is connected to the inlet of adsorption tanks 5, this steam heater 6 can be heated to steam 100 ℃-300 ℃ temperature range, automatic control system can be at required different desorption temperature of different kinds of liquid solvents and time, according to technological requirement, after the different desorption periods is heated to needed temperature with saturated steam with steam heater 6, feed adsorption tanks 5 again.This steam heater 6 can be selected different heating modes such as electrical heating, heat-conducting oil heating, combustion fuel heating or steam heated according to different needs for use.
Adopt steam heater 6, on the one hand, enter adsorption tanks 5 with vapor form and carry out desorption, steam can evenly fill the inner space of adsorption tanks 5, with the abundant desorption of organic solvent of absorption in the adsorption tanks 5, improve the desorption effect of active carbon, reduce steam consumption and shorten desorption time; On the other hand, because the organic exhaust gas that is reclaimed is the mixed organic solvents of multiple different performance, different boiling, therefore, adopt different desorption temperatures in the separating process process, can be recovered to the different solvent species and the product of ratio, make the product of retrieving (solvent of heterogeneity and ratio) be used for different paint (as priming paint, intermediate coat or finish paint etc.) occasion.Certainly, in use, can select this method desorption, also can select to adopt routine (isothermal) the desorption method desorption among the embodiment one without this method according to different paint formulation.When selecting the isothermal desorption method, can also select different isothermal desorption temperatures according to different solvents.
Other structure of present embodiment is identical with embodiment one, so repeat no more.
Cleaning, recovering and treating painted lacquer exhaust organic gas device of the present invention, focus on the basis of existing technology, before entering adsorption tanks 5 through the organic exhaust gas after filtering, absorb recover 3 by a high boiling solvent earlier, reclaim the organic solvent of condensation, stop the high boiling organic solvent in the organic exhaust gas to enter adsorption tanks 5, overcome high boiling organic solvent in the traditional handicraft is difficult to desorption in adsorption tanks 5 shortcoming.And the embodiment in this part, all are optimal design of doing according to thought of the present invention, can spray the shower nozzle 33 of liquid to filler such as absorbing at high boiling solvent to install in the recover 3, and, select different hydrojets according to the different solvents characteristic in the organic exhaust gas, solvent is reclaimed, for another example in embodiment two, for realizing that the organic exhaust gas in the adsorption tanks 5 is fully adsorbed, before steam enters adsorption tanks 5, earlier heat alternating temperature, differ and lift through steam heater 6.Every according to technological thought of the present invention, any change of being done on the technical scheme basis all falls within the protection domain of the present invention.