阅读说明：本技术 含氯有机废气净化处理工艺 (Chlorine-containing organic waste gas purification treatment process ) 是由 徐峥松 雷曙刚 于 2019-08-29 设计创作，主要内容包括：本发明提供了一种用于含氯有机废气净化处理工艺,属于废气处理技术领域。所述具体方法为对高浓度二氯甲烷、二氯乙烷、丙酰氯、氯苯等含氯有机废气进行收集,在引风机的作用下,含氯有机废气依次经过铁炭微电解反应器、UV光解设备进行处理、最后通过排气筒达标排放。本发明利用铁炭微电解对含氯有机废气进行预处理,可以最大程度降低含氯有机废气浓度,同时能将大分子物质进行氧化裂解,提高UV光解的处理效率,从而确保废气达标排放。(The invention provides a purification treatment process for chlorine-containing organic waste gas, belonging to the technical field of waste gas treatment. The specific method comprises the steps of collecting chlorine-containing organic waste gases such as high-concentration dichloromethane, dichloroethane, propionyl chloride, chlorobenzene and the like, treating the chlorine-containing organic waste gases sequentially through an iron-carbon micro-electrolysis reactor and UV photolysis equipment under the action of a draught fan, and finally discharging the chlorine-containing organic waste gases through an exhaust funnel after reaching the standard. According to the invention, the chlorine-containing organic waste gas is pretreated by utilizing iron-carbon micro-electrolysis, so that the concentration of the chlorine-containing organic waste gas can be reduced to the greatest extent, meanwhile, macromolecular substances can be subjected to oxidative cracking, the treatment efficiency of UV photolysis is improved, and the waste gas is ensured to be discharged up to the standard.)

1. The process for purifying and treating the chlorine-containing organic waste gas is characterized by comprising the following steps: chlorine-containing organic waste gas enters an iron-carbon micro-electrolysis reactor through a waste gas collecting pipeline, the gas passes through scrap iron and an active carbon packing layer from bottom to top and is fully contacted with a sprayed aqueous solution, the waste gas is firstly adsorbed by mixed packing of the scrap iron and the active carbon, because the scrap iron and the active carbon particles can form a primary battery under an acidic condition, an electrode reacts to generate H with high chemical activity, the H and the waste gas adsorbed on the surface of the mixed packing of the scrap iron and the active carbon undergo effective dechlorination reduction reaction, and the generated hydrogen chloride is dissolved in water under the washing action of the spraying liquid and is removed; step two: waste gas after dechlorination gets into UV photodissociation equipment, under the irradiation of ultraviolet ray, waste gas molecular bond fracture, form the unimolecule of free state, oxygen molecule in the air produces free oxygen under the effect of high energy UV ultraviolet ray beam, active oxygen promptly, need combine with oxygen molecule because of free oxygen is unstable, and then produce ozone, because ozone has extremely strong oxidation to the organic matter, make the organic matter unimolecule of free state form by ozone oxidation formation harmless or low harmful micromolecule compound, the tail gas after the processing passes through the aiutage and discharges up to standard.

2. The process for purifying and treating chlorine-containing organic waste gas according to claim 1, wherein the mixed filler of iron filings and activated carbon is prepared by the following method: cleaning greasy dirt on the surface of the scrap iron by using 1mol/L NaOH solution, washing the scrap iron clean, then activating the scrap iron by using 1% sulfuric acid to remove rust on the surface, washing the scrap iron to be neutral, and drying the scrap iron for later use; boiling the activated carbon with distilled water of 60-80 deg.C for 30min to remove impurities such as dust on the surface of the activated carbon, and oven drying in an oven of 80 deg.C; taking out the processed scrap iron and the activated carbon according to the mass ratio of 3: 4, uniformly mixing, and putting into an iron-carbon micro-electrolysis reactor to form an iron-carbon mixed filler layer.

3. The purification treatment process for chlorine-containing organic waste gas according to claim 1, wherein the high-energy UV light beam has a wavelength ranging from 170 to 184.9 nm.

4. The process according to claim 1, wherein the activated carbon used in the first step is waste activated carbon generated during the decolorization process.

5. The process according to claim 1, wherein the spraying solution is a sodium hypochlorite solution with a concentration of 0.6-1.0%, and when the concentration is decreased, fresh industrial sodium hypochlorite solution is periodically replenished to maintain the concentration of the spraying solution.

6. The purification treatment process of chlorine-containing organic waste gas according to claim 1, wherein the concentration of ozone in the UV photolysis apparatus is 15ppm to 48ppm, and the concentration of ozone is selected to be higher when the concentration of waste gas is higher, and to be lower when the concentration of waste gas is lower.

Technical Field

The invention belongs to the technical field of chlorine-containing organic waste gas purification treatment processes, and particularly relates to a chlorine-containing organic waste gas purification treatment process.

With the development of modern industry, chlorine-containing compounds are widely used as an important raw material in the industries of chemical industry, medicine, preservative, leather making, textile, coating, electronics, pesticide and the like, and the chlorine-containing compounds mainly contain organic matters and have volatility, so chlorine-containing organic waste gas is generated in the production and use processes.

The chlorine-containing organic compounds mainly include chlorinated hydrocarbons, chlorinated olefins, chlorinated aromatic hydrocarbons, acid chlorides, etc., representative substances of which are dichloromethane, dichloroethane, 1, 2-dichloroethylene, chlorobenzene, benzyl chloride, chloropropionyl chloride, etc., which have strong photochemical reactivity and have become a main substance of atmospheric pollution due to their high environmental toxicological characteristics.

In view of the serious environmental pollution caused by chlorine-containing organic waste gas, the treatment of chlorine-containing organic waste gas is a hot spot of the current domestic and foreign environmental research. The existing mature chlorine-containing organic waste gas treatment process mainly comprises the following steps: condensation, adsorption, organic solvent absorption, biological, photocatalytic oxidation, UV photolysis, direct combustion, and catalytic combustion.

In industrial applications, each of the conventional processes in the exhaust gas treatment process has advantages and disadvantages, and the application range thereof is limited. For example, the condensation method is generally applicable to high-concentration organic waste gas; the adsorption method is suitable for treating organic waste gas with single component, higher concentration and higher recovery and utilization value; the catalytic combustion method is suitable for treating the organic waste gas which is stable in discharge, small in air volume and free of organic waste gas which easily causes catalyst poisoning (sulfur, chlorine and nitrogen), and the direct combustion method is suitable for treating the organic waste gas which is stable in discharge, high in heat value and free of chlorine and organic waste gas which easily causes equipment corrosion.

Disclosure of Invention

The invention mainly solves the problems that the catalytic combustion method is easy to cause catalyst poisoning when treating chlorine-containing organic waste gas, the efficiency of treating the chlorine-containing organic waste gas by using single UV photolysis is not high, and the investment cost for treating the chlorine-containing organic waste gas by using the heat storage combustion method is overhigh, and provides a novel process which is feasible in technology, reasonable in economy and reliable in reaching the standard for treating the chlorine-containing organic waste gas.

In order to achieve the purpose, the technical scheme provided by the invention comprises the following two steps:

the first step is as follows: chlorine-containing organic waste gas enters the iron-carbon micro-electrolysis reactor through a waste gas collecting pipeline, the gas passes through the scrap iron and the activated carbon packing layer from bottom to top and is fully contacted with a sprayed aqueous solution, the waste gas is firstly adsorbed by the scrap iron-activated carbon mixed packing, as the scrap iron and the activated carbon particles can form a primary battery under an acidic condition, the electrode reaction generates H with high chemical activity, the H and the waste gas adsorbed on the surface of the scrap iron-activated carbon mixed packing undergo effective dechlorination reduction reaction, and the generated hydrogen chloride is dissolved in water under the washing action of the spraying liquid and is removed.

The iron filings-active carbon mixed filler is prepared by the following method: cleaning greasy dirt on the surface of the scrap iron by using 1mol/L NaOH solution, washing the scrap iron clean, then activating the scrap iron by using 1% sulfuric acid to remove rust on the surface, washing the scrap iron to be neutral, and drying the scrap iron for later use.

Boiling the activated carbon with distilled water of 60-80 deg.C for 30min to remove impurities such as dust on the surface of the activated carbon, and oven drying in an oven of 80 deg.C.

Taking out the processed scrap iron and the activated carbon according to the mass ratio of 3: 4, uniformly mixing, and putting into an iron-carbon micro-electrolysis reactor to form an iron-carbon mixed filler layer.

Chlorine-containing organic waste gas passes through the iron-carbon filler layer from bottom to top under the action of a draught fan, and spray liquid passes through the iron-carbon filler layer from top to bottom under the action of a water pump, so that countless primary batteries are formed on a three-phase interface to generate electrochemical reaction to generate high-energy activity [ H ] which is subjected to oxidation-reduction reaction with the chlorine-containing organic waste gas.

The second step is as follows: and (3) enabling the dechlorinated waste gas to enter UV photolysis equipment, and breaking molecular bonds of the waste gas under the irradiation of ultraviolet rays to form free unimolecules. Meanwhile, oxygen molecules in the air generate free oxygen under the action of the high-energy UV light beams, namely active oxygen, the free oxygen is required to be combined with the oxygen molecules due to the instability of the free oxygen, ozone is generated, single molecules of free organic matters are oxidized by the ozone to form harmless or low-harmful micromolecule compounds due to the extremely strong oxidation effect of the ozone on the organic matters, and the treated tail gas is discharged after reaching the standard through the exhaust funnel.

The product adopts a special high-energy high-ozone UV light beam (with the wavelength range of 170-184.9nm) to irradiate organic gas, so that the interior of organic gas molecules is cracked, chemical bonds are broken, and atoms or groups in a free state are formed.

The high-energy high-ozone UV light beam is used for decomposing oxygen molecules in the air to generate free oxygen, namely active oxygen, and the free oxygen is unstable and needs to be combined with the oxygen molecules to generate ozone.

The purifying equipment carries out complete oxidation decomposition reaction on the dechlorinated organic waste gas by using high-energy UV light beams and ozone, so that the organic waste gas is degraded and converted into low molecular compounds, water and carbon dioxide.

Compared with the prior art, the technology has the following advantages:

(1) chlorine-containing organic waste gas firstly passes through an iron-carbon micro-electrolysis reactor to perform dechlorination reduction reaction under the action of high-energy activity [ H ], the removal efficiency of chlorine reaches more than 95 percent, and the purified waste gas is basically free of chlorine.

(2) The iron-carbon micro-electrolysis reactor has the advantages of simple structure, small occupied area, simple and convenient operation and maintenance, long service life, easy realization of industrial application of the whole set of device and suitability for waste gas treatment of small and medium-sized factories, and can react only by adding activated carbon and scrap iron as primary batteries to form an anode and a cathode.

(3) The used filler is low in cost and easy to obtain, only scrap iron used as a corrosion electrode needs to be supplemented periodically during operation, and active carbon does not need to be replaced, so that the method is a good method for treating wastes with wastes. Extra energy consumption is not needed, and the operation cost can be greatly saved.

(4) The load bearing capacity is strong, and the influence of the environment is small. The technology can resist strong impact load, and the treatment effect is less influenced by the ambient temperature, air humidity and the like.

The invention adopts the combined technology of iron-carbon micro-electrolysis and UV photolysis to treat the chlorine-containing organic waste gas, and the iron-carbon micro-electrolysis technology can not only enable the chlorine-containing organic waste gas to be dechlorinated, reduced and released, but also enable macromolecules and organic matters which are difficult to degrade in the waste gas to be oxidized, decomposed and removed; UV photodissociation further carries out oxidative decomposition to waste gas, generates carbon dioxide and water, ensures that waste gas discharge to reach standard.

Drawings

FIG. 1 is a schematic structural diagram of a chlorine-containing organic waste gas purification treatment process device, wherein the chlorine-containing organic waste gas purification treatment process device comprises a 1-iron-carbon micro-electrolysis reactor, a 2-iron-carbon filler layer, a 3-UV photolysis device, a 4-spray pump, a 5-induced draft fan and a 6-exhaust funnel.

The specific implementation mode is as follows:

the technical solutions in the embodiments of the present invention are clearly and completely described below, and the described implementation examples are only a part of the embodiments of the present invention, not all embodiments, and the present invention is not limited by the limitations of the embodiments.

The invention provides a process for purifying and treating chlorine-containing organic waste gas, which comprises the following steps of:

(1) chlorine-containing organic waste gas enters the iron-carbon micro-electrolysis reactor from bottom to top through a waste gas collecting pipeline under the action of a draught fan, and organic chlorine is subjected to dechlorination and oxidation under the action of high-energy activity [ H ].

(2) The spray liquid passes through the iron-carbon micro-electrolysis reactor from top to bottom under the action of the spray pump and is fully contacted with the waste gas, and soluble components in the waste gas and chlorine hydride which is a dechlorination reduction product are dissolved in the spray liquid and are removed.

(3) And the organic waste gas after dechlorination enters UV photolysis equipment through a waste gas pipeline, and molecular bonds of the waste gas are broken to form small molecular compounds under the action of high-energy ultraviolet rays.

(4) Meanwhile, the oxygen in the waste gas produces ozone under the action of high-energy ultraviolet rays, and the small molecular compounds are further oxidized and decomposed into carbon dioxide and water.

(5) The waste gas treated by the process is discharged through a 15-high exhaust funnel under the action of a draught fan.

(6) The types, concentrations and air volumes of the chlorine-containing organic waste gases are different, and the selected iron-carbon mass ratio, the flow rate of the spraying liquid, the retention time, the size of equipment and the like are different greatly.

(7) Contains unsaturated bonds, vinyl chloride, chlorostyrene and the like which are easy to polymerize, when the process is adopted for treatment, high molecular polymers are easy to generate to block equipment and pipelines, and the invention is not applicable.

(8) It should be noted that, for those skilled in the art of exhaust gas treatment, various improvements and modifications can be made without departing from the technical principle of the present invention, and these improvements and modifications are also considered to be within the scope of the present invention.