An integrated wet-process waste gas multi-pollutant efficient collaborative treatment device and method

Abstract

The present invention discloses an integrated wet-process waste gas multi-pollutant efficient collaborative treatment device and method. The device is provided with a pre-oxidation section, a centrifugal liquid membrane gas-solid separation section, a wet spray absorption section, a cyclone dehydration section, an electrostatic reaction section, a packing demisting section and an adsorption + catalytic reaction section; the bottom of the device is provided with an air inlet pipe and a liquid discharge pipe, and the top is provided with an exhaust pipe; the pre-oxidation section includes an air inlet pipe, an oxidant injection pipe and a mixing plate; the centrifugal liquid membrane gas-solid separation section, the wet spray absorption section, the cyclone dehydration section, the electrostatic reaction section, the packing demisting section and the adsorption + catalytic reaction section are arranged in sequence from bottom to top. The device and method of the present invention can remove multiple waste gas pollutants such as particulate matter, sulfur dioxide, nitrogen oxides, fluoride, HCl, heavy metals, VOCs, dioxins and malodorous gases generated by industrial kilns and industrial boilers in the process of collaborative treatment of solid and hazardous waste, so that the waste gas emissions meet the emission standards and sensory requirements.

Description

Technical Field

[0001] The present invention belongs to the field of atmospheric treatment, and discloses an integrated wet-process waste gas multi-pollutant efficient collaborative treatment device and method. Background Art

[0002] While supporting the national economy and social development, industrial kilns and boilers also cause serious air pollution problems. The particulate matter and NO x The total amount of conventional waste gas pollutants, such as SO2, fluoride, HCl, and heavy metals, remains high year-round. In recent years, the coordinated treatment of solid and hazardous waste using industrial kilns and boilers has rapidly developed. This technology, through harmless and resource-based disposal, not only solves the problem of solid and hazardous waste disposal but also saves on raw materials and fuel, becoming a key path to carbon emission reduction. However, the coordinated treatment of solid and hazardous waste can increase the humidity of the waste gas and produce a large number of difficult-to-treat unconventional waste gas pollutants, such as volatile organic compounds (VOCs), dioxins, and odorous gases.

[0003] Common industrial waste gas end-of-pipe treatment technologies include bag or electrostatic dust removal, wet absorption to remove acid gases, SCR or RCO catalytic decomposition to remove NO x and VOCs, adsorption to control heavy metals and dioxins, oxidation to remove malodorous gases, etc. Although the above-mentioned technologies are installed in series separately, the purification effect of multiple pollutants in waste gas is good, but there are disadvantages such as long treatment process, large floor space, and high investment and operation costs, which hinder their large-scale promotion and application. The development of short-process and integrated efficient synergistic treatment technology for multiple pollutants in waste gas, so as to achieve efficient purification of multiple pollutants in waste gas such as particulate matter, sulfur dioxide, nitrogen oxides, fluoride, HCl, heavy metals, VOCs, dioxins and malodorous gases in the same reactor as much as possible, is the current development trend and urgent need in the field of multiple pollutant treatment of waste gas.

[0004] The development of an integrated, efficient, and coordinated treatment technology for multiple pollutants in waste gas based on a wet spray absorption tower has practical application prospects and is a direction of widespread research attention. The wet absorption tower disclosed in Chinese invention patents CN 102921278 B and CN 103505997 B can coordinately control SO2, HCl, fluoride, and NO in waste gas. x, heavy metals, dioxins and other pollutants, but this method requires pre-dust removal and cannot meet the needs of integration. The exhaust gas multi-pollutant multi-field coupling collaborative purification device disclosed in Chinese invention patent CN107233798A and utility model patent CN206996173 U can meet the needs of integrated dust removal, deacidification, removal of heavy metals and other pollutants, but the device has the disadvantage of ozone escape from the electrostatic dust removal field. If the escaped ozone is not controlled, it is very easy to pollute the surrounding atmospheric environment. The most important thing is that these two patents do not provide the specific composition of the high-efficiency absorbent. The high-efficiency absorbent is the key to the absorption tower to remove multiple pollutants from exhaust gas. However, there is still a lack of high-efficiency absorbents on the market that can synergistically remove multiple pollutants from exhaust gas such as sulfur dioxide, nitrogen oxides, fluorides, HCl, heavy metals, VOCs, dioxins and odorous gases. Chinese invention patent CN 115254423 B discloses a process and device for deep treatment of multiple pollutants in waste gas mixed with malodor. The device consists of an indirect heat exchange unit, a multi-field coupled multi-pollutant collaborative control unit, and an ozone homogeneous oxidation-heterogeneous catalysis unit. The process has a good treatment effect, but the device is not an integrated device, and the ozone decomposition unit has shortcomings such as high energy consumption of the ozone generator, low ozone utilization efficiency, high usage load of the ozone decomposition multi-effect catalyst, and frequent replacement. Summary of the Invention

[0005] In order to overcome the above-mentioned deficiencies of the prior art, the primary purpose of the present invention is to provide an integrated wet-process waste gas multi-pollutant efficient synergistic treatment device.

[0006] Another object of the present invention is to provide an integrated wet-process method for efficient and coordinated treatment of multiple pollutants in waste gas.

[0007] The purpose of the present invention is achieved through the following specific technical solutions:

[0008] An integrated wet-process waste gas multi-pollutant efficient synergistic treatment device, the device is provided with a pre-oxidation section, a centrifugal liquid membrane gas-solid separation section, a wet spray absorption section, a cyclone dehydration section, an electrostatic reaction section, a filler demisting section, and an adsorption + catalytic reaction section; the centrifugal liquid membrane gas-solid separation section, the wet spray absorption section, the cyclone dehydration section, the electrostatic reaction section, the filler demisting section, and the adsorption + catalytic reaction section are arranged in order from bottom to top in the device;

[0009] The pre-oxidation section includes an air inlet pipe, an oxidant injection pipe and a mixing plate, and the air inlet pipe is arranged at the bottom of the device; the centrifugal liquid film gas-solid separation section is composed of a centrifugal air inlet plate, a cyclone liquid film forming plate and a cyclone plate liquid inlet pipe; the wet spray absorption section is provided with a liquid spray pipe; the cyclone dehydration section is provided with a cyclone dehydration plate; the electrostatic reaction section includes a high-voltage electrostatic field and a flushing spray pipe; the packing demisting section is provided with a packing demisting screen; the adsorption + catalytic reaction section is provided with an adsorption + catalytic material layer;

[0010] The bottom of the device is also provided with a liquid drain pipe, and the top of the device is provided with an exhaust pipe.

[0011] The present invention uses a wet spray absorption tower as the core equipment, improves the exhaust gas multi-pollutant multi-field coupled collaborative purification device disclosed in Chinese patent CN 206996173 U, adds a pre-oxidation section, separates the packing demisting and adsorption section into a packing demisting section and an adsorption + catalytic section, and adopts a treatment mode of "pre-oxidation modulation - centrifugal liquid membrane gas-solid separation - wet spray absorption - electrostatic reaction - adsorption + catalytic reaction" to deeply purify the exhaust gas.

[0012] Based on the above device, the present invention also provides an integrated wet process waste gas multi-pollutant efficient collaborative treatment method, the method comprising the following steps:

[0013] (1) The waste gas to be treated enters the pre-oxidation section, is mixed with the oxidant, and is introduced tangentially into the device, and then enters the centrifugal liquid film gas-solid separation section; under the guidance of the centrifugal air inlet plate, the gas moves upward in a spiral along the tower wall, and the absorbent forms thin film droplets on the cyclonic liquid film forming plate. Under the combined action of centrifugal force and thin film droplets, particulate matter and attached heavy metals in the waste gas are removed;

[0014] (2) The waste gas treated in step (1) enters the wet spray absorption section, where most of the sulfur dioxide, nitrogen oxides, fluorides, HCl, inorganic odors and most of the difficult-to-degrade dioxins, VOCs and organic odor gases in the waste gas are removed by washing with a water-based composite absorbent;

[0015] (3) The gas after wet spray absorption in step (2) enters the cyclone dehydration section for dehydration, and then enters the electrostatic reaction section, where particulate matter and attached heavy metals are deeply removed under the action of electrostatics. At the same time, a small amount of remaining dioxins, VOCs, and organic odorous gases undergo a gas-gas homogeneous oxidation reaction with the ozone generated by static electricity and are removed;

[0016] (4) The waste gas treated in step (3) enters the packing demisting section to regulate the water vapor content in the waste gas, and then enters the adsorption + catalytic material layer. The remaining dioxins, VOCs, and organic odorous gases undergo ozone catalytic oxidation reaction under the action of the catalyst, and the residual pollutants are also adsorbed in this layer. The waste gas is deeply purified and meets the emission standards or even deep treatment (ultra-low emission) requirements and is discharged through the exhaust pipe.

[0017] Preferably, the oxidant in step (1) is at least one of gaseous ozone, liquid hydrogen peroxide, calcium hypochlorite, ammonium persulfate, potassium permanganate, and sodium chlorite.

[0018] Preferably, the water-based composite absorbent components in step (2) are composed of the following components in parts by mass: 50-100 parts of urea, 100-200 parts of alkaline substances, 8-16 parts of active additives and 1500-6000 parts of water; the active additive is a compound of an organosilicon nonionic surfactant and an active ingredient.

[0019] More preferably, the active ingredient is the active ingredient of the composite absorbent disclosed in Chinese invention patent CN 114210174 A, and the specific preparation steps include: heating and dehydrating the raw materials; then adding acid and continuously stirring; then adding alkali solution and continuously stirring to obtain the active ingredient; the raw materials are one or more of soybean oil, palm oil, corn oil, peanut oil, olive oil, rapeseed oil, safflower oil, sunflower oil, canola oil, sea buckthorn seed oil, tea oil, sacha inchi oil, linseed oil, argan oil, and walnut oil; in the preparation of the active ingredient, the heating and dehydration temperature is 50-150°C, the heating and dehydration time is 0.5-5h, the first and second stirring temperatures are both 20-100°C, and the stirring time is both 2-10h.

[0020] More preferably, the alkaline substance is at least one of sodium hydroxide, potassium hydroxide, limestone and lime.

[0021] More preferably, the mass ratio of the organosilicon nonionic surfactant to the active ingredient is 0.2-2:5-10.

[0022] More preferably, the organosilicon nonionic surfactant is polyether-modified silicone oil.

[0023] More preferably, the organosilicon nonionic surfactant is at least one of SYLGARD™ OFX-0309 Fluid and XIAMETER™ OFX-0193 Fluid polyether-modified silicone oils.

[0024] Preferably, the adsorption + catalytic material in the adsorption + catalytic material layer in step (4) consists of a substrate, a coating and an active component;

[0025] The matrix is ​​any one of integral honeycomb, strip, and plate-shaped activated carbon;

[0026] The coating is LaMn composed of metal lanthanum (La), manganese (Mn), copper (Cu), iron (Fe), and chromium (Cr). 1-x M x O3 (M = Cu, Fe, Cr) perovskite oxide, x = 0.2~0.8;

[0027] The active component is nano manganese dioxide (MnO2).

[0028] More preferably, the substrate is activated carbon having an iodine value greater than 800 mg / g.

[0029] More preferably, the adsorption + catalysis material is prepared by the following method:

[0030] Step 1: Synthesis of LaMn series by conventional sol-gel method 1-x M x O3 perovskite oxide;

[0031] Step 2: LaMn 1-x M x O3 perovskite oxide and coal tar are mixed in a mass ratio of 1:0.1-0.3, and water is added to obtain a coating slurry;

[0032] Step 3: Immerse the substrate in the coating slurry prepared in step 2 for 24-32 hours. Remove the substrate and allow it to stand to remove excess slurry from the entire material. Blow it with hot air to ensure that the pores are not blocked. Dry the material and then calcine it.

[0033] Step 4: Repeat the impregnation, drying and calcination process in step 3 to finally obtain the monolithic LaMn 1-x M x For O3 / activated carbon samples, the loading amount of the perovskite oxide coating on the substrate is 2-6 wt.%;

[0034] Step 5: The monolithic LaMn 1-x M x The O3 / activated carbon samples were immersed in Mn(NO3)2 solution for 24-32 h, taken out, purged with hot air, dried, and then calcined;

[0035] Step 6: Repeat the impregnation, drying and calcination process of step 5 to finally obtain the monolithic MnO2 / LaMn 1-x M x The O3 / activated carbon sample is the adsorption + catalytic material, in which the MnO2 loading is 10~20 wt.%.

[0036] More preferably, the calcination temperature in the third and fifth steps is 300-500° C., and the calcination time is 3-6 h; and the drying in the third and fifth steps is drying at 100-110° C. for 30-36 h.

[0037] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0038] (1) The present invention improves the existing multi-pollutant multi-field coupled coordinated purification device for waste gas (CN 206996173 U) by adding a pre-oxidation section. The pre-oxidation improves the solubility of pollutants in water, promotes the conversion of SO2 and NO, which are insoluble in water, into SO3 and NO2, which are highly soluble. The VOCs, dioxins and malodorous substances that are difficult to decompose are modulated to generate some oxidation intermediates that are easily decomposed or water-soluble. The SO2, NO, VOCs, dioxins and malodorous substances in the waste gas can be fully oxidized at the air inlet of the device, avoiding the previous problem of reoxidizing the pollutants in the spray section, and significantly improving the oxidation efficiency and the absorption efficiency of the spray section.

[0039] (2) The water-based composite absorption liquid developed by the present invention fundamentally avoids the secondary pollution and flammability and explosion problems caused by the volatilization of the organic absorption liquid. By using the water-based composite absorption liquid, the inorganic odorous substance ammonia in the waste gas that is soluble in water is directly absorbed by water, and the fluoride, HCl in the waste gas and the sulfate (SO4 2- ) is absorbed and neutralized by alkali solution, NO x Under the action of urea, it is converted into N2. The active additive in the water-based composite absorption liquid is a compound material composed of an organic silicon nonionic surfactant and the active ingredient described in the invention patent CN 114210174 A. The active ingredient described in the invention patent CN 114210174 A is equivalent to an anionic surfactant. The organic silicon nonionic surfactant is combined with the anionic surfactant. Due to the difference in groups between the organic silicon nonionic and the anionic, the molecules of the organic silicon nonionic surfactant are easily embedded in the micelles formed by the anionic surfactant. The repulsion of the hydrophobic groups inside the micelles in the solution becomes smaller, and the critical micelle concentration is significantly reduced, making it easier for micelles to form. At the same time, the SO4 absorbed by the alkali solution 2- 、Cl - and F - It can act as an inorganic salt adjuvant to reduce the repulsion between surfactant ion heads, further promoting the formation of micelles. A key characteristic of micelles is their solubilization effect. The more micelles there are, the more solubility VOCs, dioxins, and organic malodorous substances increase, significantly improving absorption efficiency. Under the action of the water-based composite absorption liquid, nearly all sulfur dioxide, nitrogen oxides, fluoride, HCl, and most difficult-to-treat dioxins, VOCs, and malodorous gases in the exhaust gas are removed.

[0040] (3) The present invention also separates the packing demisting adsorption section into a packing demisting section and an adsorption + catalytic section. The adsorption + catalytic material layer is the final barrier for exhaust gas purification. The packing demisting section can regulate the water vapor content in the exhaust gas, reduce the competitive adsorption between water vapor and ozone, VOCs, dioxins and organic odorous gases in the adsorption + catalytic material layer, and significantly improve the purification efficiency of the adsorption + catalytic material. The adsorption + catalytic section is set as an integral MnO2 / LaMn 1-x M x O3 / activated carbon material layer, MnO2 / LaMn 1-x M x The surface of O3 / activated carbon materials contains a large number of oxygen vacancies. In an environment with an appropriate amount of water vapor, ozone adsorbed on the oxygen vacancies will be activated to generate highly active oxygen species (O ‒ 、O2 ‒ Ozone catalytic oxidation of VOCs, dioxins, and organic odor molecules, under the action of highly reactive oxygen species, decomposes them into CO₂, H₂O, and oxidation products. Ozone is also removed in this process by generating O₂. Small amounts of residual VOCs, dioxins, odorous gases, and ozone catalytic oxidation products are adsorbed by activated carbon. Exhaust gas flows from bottom to top through the various reaction stages of the integrated wet-process, multi-pollutant, and highly efficient coordinated exhaust gas purification unit, achieving advanced treatment and discharge through the exhaust stack, meeting emission standards or even advanced treatment (ultra-low emission) requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a structural diagram of an integrated wet-process waste gas multi-pollutant efficient collaborative treatment device of the present invention;

[0042] In the figure, 1 is the pre-oxidation section, 1-1 is the oxidant injection pipe, 1-2 is the mixing plate, 2 is the centrifugal liquid film gas-solid separation section, 2-1 is the centrifugal air inlet plate, 2-2 is the cyclone liquid film forming plate, 2-3 is the cyclone plate liquid inlet pipe, 3 is the wet spray absorption section, 3-1 is the liquid spray pipe, 4 is the cyclone dehydration section, 4-1 is the cyclone dehydration plate, 5 is the electrostatic reaction section, 5-1 is the high-voltage electrostatic field, 5-2 is the flushing spray pipe, 6 is the packing demisting section, 6-1 is the packing demisting screen, 7 is the adsorption + catalytic reaction section, and 7-1 is the adsorption + catalytic material layer. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below with reference to specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is subject to the claims. Unless otherwise specified, the reagents used in the examples can be purchased from conventional commercial sources.

[0044] like Figure 1As shown, the present invention provides an integrated wet-process waste gas multi-pollutant efficient synergistic treatment device, the purification device is provided with a pre-oxidation section 1, a centrifugal liquid membrane gas-solid separation section 2, a wet spray absorption section 3, a cyclone dehydration section 4, an electrostatic reaction section 5, a filler demisting section 6 and an adsorption + catalytic reaction section 7; the centrifugal liquid membrane gas-solid separation section 2, the wet spray absorption section 3, the cyclone dehydration section 4, the electrostatic reaction section 5, the filler demisting section 6 and the adsorption + catalytic reaction section 7 are arranged in the device from bottom to top in sequence;

[0045] The pre-oxidation section 1 includes an air inlet pipe, an oxidant injection pipe 1-1 and a mixing plate 2-2, wherein the air inlet pipe is arranged at the bottom of the device; the centrifugal liquid film gas-solid separation section 2 is composed of a centrifugal air inlet plate 2-1, a cyclone liquid film forming plate 2-2 and a cyclone plate liquid inlet pipe 2-3; the wet spray absorption section 3 is provided with a liquid spray pipe 3-1; the cyclone dehydration section 4 is provided with a cyclone dehydration plate 4-1; the electrostatic reaction section 5 includes a high-voltage electrostatic field 5-1 and a flushing spray pipe 5-2; the packing demisting section 6 is provided with a packing demisting screen 6-1; and the adsorption + catalytic reaction section 7 is provided with an adsorption + catalytic material layer 7-1;

[0046] The bottom of the device is also provided with a liquid drain pipe, and the top of the device is provided with an exhaust pipe.

[0047] Example 1: Monolithic MnO2 / LaMn 0.6 Cu 0.4 O3 / activated carbon adsorption + catalytic material layer

[0048] Monolithic MnO2 / LaMn 0.6 Cu 0.4 The preparation process of O3 / activated carbon adsorption + catalytic material includes the following specific steps:

[0049] Step 1: Synthesis of LaMn series by conventional sol-gel method 0.6 Cu 0.4 O3 perovskite oxide;

[0050] Step 2: LaMn 0.6 Cu 0.4 O3 perovskite oxide and binder coal tar are mixed in a mass ratio of 1:0.2, and deionized water is added to obtain a coating slurry;

[0051] Step 3: Immerse the honeycomb activated carbon with an iodine value greater than 800 mg / g in the coating slurry for 24 hours, remove it and let it stand to remove excess slurry from the whole material, and blow it with hot air to ensure that the channels are not blocked;

[0052] Step 4: Dry at 105 °C and calcine in a 350 °C calciner for 4 h;

[0053] Step 5: Repeat the impregnation, drying and calcination process of steps 3 and 4 to obtain a monolithic LaMn with a perovskite oxide coating loading of about 5 wt.% 0.6 Cu 0.4 O3 / activated carbon samples;

[0054] Step 6: Prepare the monolithic LaMn 0.6 Cu 0.4 The O3 / activated carbon sample was immersed in Mn(NO3)2 solution for a period of time, taken out and purged with hot air, dried at 105℃, and calcined in a 350℃ calcining furnace;

[0055] Step 7: Repeat the impregnation, drying and calcination process of step 6 to finally obtain a monolithic MnO2 / LaMn with an active component loading of about 10 wt.%. 0.6 Cu 0.4 O3 / activated carbon samples.

[0056] Example 2: Active ingredient

[0057] The active ingredient is prepared with reference to the invention patent with publication number "CN 114210174 A" and titled "A method for treating malodor and organic waste gas by enhanced absorption / adsorption coupling", which includes the following specific steps:

[0058] In the first step, soybean oil was heated and dehydrated at 130 °C for 3 h;

[0059] In the second step, 1 mol / L dilute hydrochloric acid was added to the slurry after heating and dehydration in the first step, and the mixture was stirred continuously at 30 °C for 5 h to prevent local overheating.

[0060] In the third step, 1 mol / L dilute sodium hydroxide alkali solution was added to the slurry prepared in the second step and stirred at 30 °C for 5 h to obtain the active ingredient.

[0061] Comparative Example 1: Monolithic MnO2 / activated carbon adsorption + catalytic material layer

[0062] The preparation process of the monolithic MnO2 / activated carbon adsorption + catalytic material includes the following specific steps:

[0063] Step 1: Immerse the honeycomb activated carbon sample with an iodine value greater than 800 mg / g in a Mn(NO3)2 solution for a period of time, take it out and blow it with hot air, dry it at 105°C, and calcine it in a 350°C calcining furnace;

[0064] Step 2: Repeat the impregnation, drying and calcination process of the first step to finally obtain a monolithic MnO2 / activated carbon sample with an active component loading of about 10 wt.%.

[0065] In the following examples 1 to 3 and comparative examples 1 to 9, the waste gas treated is the inlet waste gas of a certain industrial furnace co-processing sludge plant, and the waste gas composition (average concentration) is: particulate matter 465 mg / m 3 , sulfur dioxide 1078 mg / m 3 , nitrogen oxides 59mg / m 3 , fluoride 8 mg / m 3 HCl 23 mg / m 3 , heavy metals 5 mg / m 3 、TVOC 27.5 mg / m 3 、Dioxin 0.18ngTEQ / m 3 And the concentrated odor emission concentration is 17378 (dimensionless); the device used to treat the waste gas is Figure 1 The integrated wet-process waste gas multi-pollutant efficient collaborative treatment device shown has the following specific treatment steps:

[0066] (1) The waste gas to be treated enters the pre-oxidation section, is mixed with the oxidant, and is introduced tangentially into the device, and then enters the centrifugal liquid film gas-solid separation section; under the guidance of the centrifugal air inlet plate, the gas moves upward in a spiral along the tower wall, and the absorbent forms thin film droplets on the cyclonic liquid film forming plate. Under the combined action of centrifugal force and thin film droplets, particulate matter and attached heavy metals in the waste gas are removed;

[0067] (2) The waste gas treated in step (1) enters the wet spray absorption section, where most of the sulfur dioxide, nitrogen oxides, fluorides, HCl, inorganic odors and most of the difficult-to-degrade dioxins, VOCs and organic odor gases in the waste gas are removed by washing with a water-based composite absorbent;

[0068] (3) The gas after wet spray absorption in step (2) enters the cyclone dehydration section for dehydration, and then enters the electrostatic reaction section, where particulate matter and attached heavy metals are deeply removed under the action of electrostatics. At the same time, a small amount of remaining dioxins, VOCs, and organic odorous gases undergo a gas-gas homogeneous oxidation reaction with the ozone generated by static electricity and are removed;

[0069] (4) The waste gas treated in step (3) enters the packing demisting section to regulate the water vapor content in the waste gas, and then enters the adsorption + catalytic material layer. The remaining dioxins, VOCs, and organic odorous gases undergo ozone catalytic oxidation reaction under the action of the catalyst, and the residual pollutants are also adsorbed in this layer. The waste gas is deeply purified and meets the emission standards or even deep treatment (ultra-low emission) requirements and is discharged through the exhaust pipe.

[0070] The compositions of the absorption liquids used in the following Examples 1 to 3 and Comparative Examples 1 to 9 are shown in Table 1. The raw material parts in the table are parts by mass. The organosilicon nonionic surfactant used is SYLGARD™ OFX-0309 Fluid polyether-modified silicone oil.

[0071] Table 1 Composition of water-based composite absorption liquid

[0072]

[0073] Effect Example 1

[0074] In this embodiment, the oxidant of the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 1, and the adsorption + catalytic material prepared in Example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 3.2 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides were 1.03 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.06 mg / m 3 , TVOC 0.91 mg / m 3 No dioxins were detected, the concentrated odor emission concentration was 309 (dimensionless), and ozone was 0.89 mg / m 3 In this embodiment, the removal efficiency of multiple pollutants in the exhaust gas is higher than 95%, meeting the emission standards and odor sensory requirements.

[0075] Effect Example 2

[0076] In this embodiment, the oxidant of the pre-oxidation section is liquid sodium chlorite, the water-based composite absorption liquid is absorption liquid 2, and the adsorption + catalytic material prepared in Example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 4.3 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides 1.65 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.04 mg / m 3 , TVOC 1.11 mg / m 3 No dioxins were detected, the odor concentration was 417 (dimensionless), and ozone was 0.13 mg / m 3 In this embodiment, the removal efficiency of multiple pollutants in the exhaust gas is higher than 95%, meeting the emission standards and odor sensory requirements.

[0077] Effect Example 3

[0078] In this embodiment, the oxidant of the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 3, and the adsorption + catalytic material prepared in Example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 3.6 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides were 1.73 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.07 mg / m 3 , TVOC 1.04 mg / m 3 No dioxins were detected, the concentrated odor emission concentration was 309 (dimensionless), and ozone was 0.96 mg / m 3 In this embodiment, the removal efficiency of multiple pollutants in the exhaust gas is higher than 95%, meeting the emission standards and odor sensory requirements.

[0079] Effect Comparative Example 1

[0080] In this comparative example, the oxidant in the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 4, and the adsorption + catalytic material prepared in Example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 4.0 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides were 1.91 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.12 mg / m 3 , TVOC 10.6 mg / m 3 , dioxin 0.07ng TEQ / m 3 , odor emission concentration 3090 (dimensionless), ozone 0.74 mg / m 3 It can be seen that when the water-based composite absorption liquid is used, the removal efficiency of TVOC and dioxins is about 60%.

[0081] Effect Comparative Example 2

[0082] In this comparative example, the oxidant in the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 5, and the adsorption + catalytic material prepared in Example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 3.8 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides were 1.45 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.09 mg / m3 , TVOC 7.95 mg / m 3 , dioxin 0.055ng TEQ / m 3 , odor emission concentration 550 (dimensionless), ozone 1.3 mg / m 3 It can be seen that when the water-based composite absorption liquid is used, the removal efficiency of TVOC and dioxins is about 70%, which does not meet the odor sensory requirements.

[0083] Effect Comparative Example 3

[0084] In this comparative example, the oxidant in the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 6, and the adsorption + catalytic material prepared in Example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 5.1 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides 1.65 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.14 mg / m 3 , TVOC 17.73 mg / m 3 , dioxin 0.11ng TEQ / m 3 , concentrated odor emission concentration 4168 (dimensionless), ozone 0.8 mg / m 3 It can be seen that when the water-based composite absorption liquid is used, the removal efficiency of TVOC and dioxins is less than 50%, which does not meet the odor sensory requirements.

[0085] Effect Comparative Example 4

[0086] In this comparative example, the oxidant in the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 7, and the adsorption + catalytic material prepared in Example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 5.3 mg / m 3 , sulfur dioxide 598.87 mg / m 3 , nitrogen oxides 36.12 mg / m 3 , fluoride 4.32 mg / m 3 and HCl 11.68 mg / m 3 , heavy metals 0.68 mg / m 3 , TVOC 1.94 mg / m 3 , dioxin 0.06ng TEQ / m 3 , concentrated odor emission concentration 550 (dimensionless), ozone 1.1 mg / m3 It can be seen that when the water-based composite absorption liquid is used, the removal efficiency of sulfur dioxide, nitrogen oxides, fluoride and HCl is less than 50%, which is difficult to meet the removal requirements of acidic waste gas.

[0087] Effect Comparative Example 5

[0088] In this comparative example, the oxidant in the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 8, and the adsorption + catalytic material prepared in Example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 4.8 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides were 1.84 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.12 mg / m 3 , TVOC 18.34 mg / m 3 , dioxin 0.12ng TEQ / m 3 , concentrated odor emission concentration 9772 (dimensionless), ozone 1.8 mg / m 3 It can be seen that when the water-based composite absorption liquid is used, the TVOC and dioxin removal efficiency is less than 40%, which is difficult to meet the requirements for the removal of organic waste gas and the odor sensory requirements.

[0089] Effect Comparative Example 6

[0090] In this comparative example, the oxidant in the pre-oxidation section was liquid calcium hypochlorite, the water-based composite absorption liquid was absorption liquid 9, and the adsorption + catalytic material prepared in Example 1 was placed. The exhaust gas passed through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration was: particulate matter 4.8 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides were 1.60 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.20 mg / m 3 , TVOC 9.51 mg / m 3 , dioxin 0.06ng TEQ / m 3 , concentrated odor emission concentration 2344 (dimensionless), ozone 1.4 mg / m 3 It can be seen that when the water-based composite absorption liquid is used, the TVOC and dioxin removal efficiency is about 65%, which does not meet the odor sensory requirements.

[0091] Effect Comparative Example 7

[0092] In this comparative example, the oxidant in the pre-oxidation section was liquid calcium hypochlorite, the water-based composite absorption liquid was absorption liquid 10, and the adsorption + catalytic material prepared in Example 1 was placed. The exhaust gas passed through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration was: particulate matter 4.1 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides 1.00 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.10 mg / m 3 , TVOC 16.12 mg / m 3 , dioxin 0.11ng TEQ / m 3 , odor emission concentration 5495 (dimensionless), ozone 1 mg / m 3 It can be seen that when the water-based composite absorption liquid is used, the TVOC and dioxin removal efficiency is about 40%, which does not meet the odor sensory requirements.

[0093] Effect Comparative Example 8

[0094] In this comparative example, the oxidant in the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 1, and no adsorption + catalytic material is placed. After the exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section" from bottom to top, the average outlet concentration is: particulate matter 4.4 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides were 1.87 mg / m 3 , fluoride and HCl were not detected, heavy metals were 0.14 mg / m 3 , TVOC 5.96 mg / m 3 , dioxin 0.09ng TEQ / m 3 , concentrated odor emission concentration 2344 (dimensionless), ozone 20 mg / m 3 It can be seen that without the placement of adsorption + catalytic materials, the TVOC and dioxin removal efficiency is less than 70%, which does not meet the odor sensory requirements and there is residual ozone emission.

[0095] Effect Comparative Example 9

[0096] In this comparative example, the oxidant in the pre-oxidation section is gaseous ozone, the water-based composite absorption liquid is absorption liquid 1, and the adsorption + catalytic material prepared in comparative example 1 is placed. The exhaust gas passes through the "pre-oxidation modulation section - centrifugal liquid membrane gas-solid separation section - wet spray absorption section - electrostatic reaction section - adsorption + catalytic reaction section" from bottom to top, and the average outlet concentration is: particulate matter 3.8 mg / m 3 , sulfur dioxide was not detected, nitrogen oxides were 1.45 mg / m 3, fluoride and HCl were not detected, heavy metals were 0.09 mg / m 3 , TVOC 4.08 mg / m 3 , dioxin 0.03ng TEQ / m 3 , odor emission concentration 417 (dimensionless), ozone 11 mg / m 3 It can be seen that when the uncoated adsorption + catalytic material of Comparative Example 1 is used, the TVOC and dioxin removal efficiency is about 85%, and it is difficult to remove residual VOCs, dioxins, organic odorous waste gas and ozone.

[0097] It can be seen from the removal effects of multiple pollutants in waste gas of Effect Examples 1, 2, 3 and Effect Comparative Example 1 that the compounding ratio of the organosilicon nonionic surfactant and the active ingredient of the composite absorbent in invention patent CN 114210174 A affects the removal efficiency of TVOC, dioxins and organic malodorous gases. A compounding ratio outside the range of 0.2-2:5-10 will lead to a significant decrease in the removal efficiency of TVOC, dioxins and organic malodorous gases. For example, in Effect Comparative Example 1, the compounding ratio of the two is 3:4, resulting in a decrease in the removal efficiency of TVOC, dioxins and organic malodorous gases from 95% to 60%.

[0098] It can be seen from the removal effects of multiple pollutants in waste gas of Example 1 and Comparative Example 2 that the addition of organosilicon nonionic surfactant improves the removal efficiency of TVOC, dioxins and organic odorous gases, and the removal efficiency is increased from 70% to 95%. This is closely related to the fact that the organosilicon nonionic surfactant significantly reduces the critical micelle concentration of the absorption liquid, promotes micelle formation, and increases the solubility of TVOC, dioxins and organic odorous gases.

[0099] It can be seen from the waste gas multi-pollutant removal effects of Example 1 and Comparative Example 3 that the organosilicon nonionic surfactant alone is not sufficient to effectively remove TVOC, dioxins and organic malodorous gases. It must be used together with the active ingredients in the invention patent CN114210174 A to effectively remove TVOC, dioxins and organic malodorous gases. The organosilicon nonionic surfactant is equivalent to the TVOC, dioxin and organic malodorous gas solubilizing agent in the absorption liquid of the invention patent CN 114210174 A.

[0100] It can be seen from the removal effects of multiple pollutants from waste gas in Example 1, Comparative Example 4 and Comparative Example 5 that the mass fraction of each component of the water-based composite absorbent directly affects the removal efficiency of multiple pollutants from waste gas. Since the alkali in the water-based composite absorbent is mainly responsible for the absorption of acidic components such as sulfur dioxide, nitrogen oxides, fluoride, and HCl, urea absorbs NO xReduced to N2, the active additive is responsible for removing VOCs, dioxins, and organic malodorous gases. In the comparative example 4, the alkali and urea are not in the optimal proportion range, and the removal efficiency of acidic components such as sulfur dioxide, nitrogen oxides, fluorides, and HCl is seriously affected. The removal efficiency of sulfur dioxide, nitrogen oxides, fluorides, and HCl are all lower than 50%, which is difficult to meet the removal requirements of acidic waste gas; and in the comparative example 5, the active additive is not in the optimal proportion range, and the removal efficiency of VOCs, dioxins, and organic malodorous gases is seriously affected. The removal efficiency of TVOC and dioxins is lower than 40%, which is difficult to meet the removal requirements of organic waste gas and the odor sensory requirements.

[0101] It can be seen from the removal effects of multiple pollutants in waste gas of Example 1, Comparative Examples 6 and 7 that the removal effect of VOCs, dioxins and organic malodorous gases by the compound solution of the active ingredient in the invention patent CN 114210174 A and the organosilicon nonionic surfactant is much better than that by the compound solution with the polyoxyethylene nonionic surfactant TW20 and the cationic surfactant CTAB.

[0102] It can be seen from the exhaust gas multi-pollutant removal effects of Example 1, Comparative Example 8 and Comparative Example 9 that the adsorption + catalytic material prepared by the present invention can effectively remove residual VOCs, dioxins, malodorous gases and ozone, and the LaMn loaded by the adsorption + catalytic material 1-x M x The O3 coating effectively improves the removal efficiency of VOCs, dioxins, malodorous gases and ozone of MnO2 / activated carbon materials.

[0103] The applicant declares that the above embodiments are preferred implementation methods of the invention, but the implementation methods of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. An integrated wet process for efficient and coordinated treatment of multiple pollutants in waste gas, characterized in that: The following steps are involved: (1) The waste gas to be treated enters the pre-oxidation section, is mixed with the oxidant, and is introduced tangentially into the device, and then enters the centrifugal liquid film gas-solid separation section; under the guidance of the centrifugal air inlet plate, the gas moves upward in a spiral along the tower wall, and the absorbent forms thin film droplets on the cyclonic liquid film forming plate. Under the combined action of centrifugal force and thin film droplets, particulate matter and attached heavy metals in the waste gas are removed; the waste gas to be treated is the flue gas of industrial kilns and / or industrial boilers; (2) The waste gas treated in step (1) enters the wet spray absorption section, and is washed with a water-based composite absorbent to remove most of the sulfur dioxide, nitrogen oxides, fluorides, HCl, inorganic odors and most of the difficult-to-degrade dioxins, VOCs and organic odor gases in the waste gas; the water-based composite absorbent components are composed of the following by mass: 50-100 parts of urea, 100-200 parts of alkaline substances, 8-16 parts of active additives and 1500-6000 parts of water; the active additive is a compound material of polyether-modified silicone oil and active ingredients in a mass ratio of 0.2-2:5-10; (3) The gas after wet spray absorption in step (2) enters the cyclone dehydration section for dehydration, and then enters the electrostatic reaction section, where particulate matter and attached heavy metals are deeply removed under the action of electrostatics. At the same time, a small amount of remaining dioxins, VOCs, and organic odorous gases undergo a gas-gas homogeneous oxidation reaction with the ozone generated by static electricity and are removed; (4) The waste gas treated in step (3) enters the packing demisting section to regulate the water vapor content in the waste gas, and then enters the adsorption + catalytic material layer. The remaining dioxins, VOCs, and organic odorous gases undergo ozone catalytic oxidation reaction under the action of the catalyst, and the residual pollutants are also adsorbed in this layer. The waste gas is deeply purified and meets the emission standards or even deep treatment requirements and is discharged through the exhaust pipe; The adsorption + catalytic material layer is prepared by the following method: Step 1: Synthesis of LaMn series by conventional sol-gel method 1-x M x O3 perovskite-type oxide; x = 0.2~0.8, M = Cu, Fe or Cr; Step 2: LaMn 1-x M x O3 perovskite oxide and coal tar are mixed in a mass ratio of 1:0.1-0.3, and water is added to obtain a coating slurry; Step 3: Immerse the substrate in the coating slurry prepared in step 2 for 24-32 hours, remove it and let it stand to remove excess slurry from the whole material, blow it with hot air; dry the material and then calcine it; Step 4: Repeat the impregnation, drying and calcination process in step 3 to finally obtain the monolithic LaMn 1-x M x For O3 / activated carbon samples, the loading amount of the perovskite oxide coating on the substrate is 2-6 wt.%; Step 5: The monolithic LaMn 1-x M x The O3 / activated carbon samples were immersed in Mn(NO3)2 solution for 24-32 h, taken out, purged with hot air, dried, and then calcined; Step 6: Repeat the impregnation, drying and calcination process of step 5 to finally obtain the monolithic MnO2 / LaMn 1-x M x The O3 / activated carbon sample is the adsorption + catalytic material, in which the MnO2 loading is 10~20 wt.%.

2. The method according to claim 1, characterized in that The oxidant in step (1) is at least one of gaseous ozone, liquid hydrogen peroxide, calcium hypochlorite, ammonium persulfate, potassium permanganate, and sodium chlorite.

3. The method according to claim 1, characterized in that The active ingredient is prepared by the following method: heating and dehydrating the raw materials; then adding acid and continuously stirring; then adding alkali solution and continuously stirring to obtain the active ingredient; the raw materials are one or more of soybean oil, palm oil, corn oil, peanut oil, olive oil, rapeseed oil, safflower oil, sunflower oil, canola oil, sea buckthorn seed oil, tea oil, sacha inchi oil, linseed oil, argan oil, and walnut oil; the heating and dehydration temperature is 50-150°C, the heating and dehydration time is 0.5-5 hours, the first and second stirring temperatures are both 20-100°C, and the stirring time is both 2-10 hours.

4. The method according to claim 1, wherein The alkaline substance is at least one of sodium hydroxide, potassium hydroxide, limestone and lime.

5. The method according to claim 1, wherein The adsorption + catalytic material in the adsorption + catalytic material layer in step (4) is composed of a substrate, a coating and an active component; The matrix is ​​any one of integral honeycomb, strip, and plate-shaped activated carbon; The coating is LaMn composed of metal lanthanum, manganese, copper, iron and chromium 1-x M x O3 perovskite oxide, x = 0.2~0.8, M = Cu, Fe or Cr; The active component is nano manganese dioxide.

6. The method according to claim 5, characterized in that The matrix is ​​activated carbon with an iodine value greater than 800 mg / g.

7. The method according to claim 1, characterized in that The calcination temperature in the third and fifth steps is 300-500°C, and the calcination time is 3-6 hours. The drying in the third and fifth steps refers to drying at 100-110°C for 30-36 hours.

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