阅读说明：本技术 一种环氧乙烷废气的吸收装置及处理环氧乙烷废气的方法 (Device for absorbing ethylene oxide waste gas and method for treating ethylene oxide waste gas ) 是由 车飞 张宝龙 于 2019-09-24 设计创作，主要内容包括：本发明公开了一种环氧乙烷废气的吸收装置及处理环氧乙烷废气的方法,属于废气吸收设备领域,其技术要点：一种环氧乙烷废气的吸收装置按照废气处理的顺序依次包括进气管、冷凝分离装置、催化吸收装置、冷凝分离装置、喷淋吸收塔组、旋流气液分离器、微波光电催化氧化炉、离心风机以及烟囱。其处理的方法包括将环氧乙烷废气经冷凝分离装置冷却至10℃以下分离气液；步骤一的废气导入催化吸收槽的液面下鼓泡；然后废气由碱性喷淋和酸性喷淋以吸收废气内的环氧乙烷；废气内多余水汽经旋流气液分离器分离气液得到干燥废气；然后微波光电催化氧化炉催化氧化,得到无害气体,随后经烟囱放空。降低了环氧乙烷废气中环氧乙烷的排放量,达到国家排放标准。(The invention discloses an absorption device of ethylene oxide waste gas and a method for treating the ethylene oxide waste gas, which belong to the field of waste gas absorption equipment and are technically characterized in that: an absorption device for ethylene oxide waste gas sequentially comprises an air inlet pipe, a condensation separation device, a catalytic absorption device, a condensation separation device, a spraying absorption tower set, a rotational flow gas-liquid separator, a microwave photoelectrocatalysis oxidation furnace, a centrifugal fan and a chimney according to the waste gas treatment sequence. The treatment method comprises cooling the ethylene oxide waste gas to below 10 deg.C by a condensation separation device to separate gas and liquid; introducing the waste gas in the first step into a catalytic absorption tank for bubbling below the liquid level; then the waste gas is sprayed by alkali and acid to absorb the ethylene oxide in the waste gas; surplus water vapor in the waste gas is separated into gas and liquid through a cyclone gas-liquid separator to obtain dry waste gas; then the harmless gas is obtained by catalytic oxidation in a microwave photoelectrocatalysis oxidation furnace, and then the harmless gas is discharged through a chimney. The discharge amount of the ethylene oxide in the ethylene oxide waste gas is reduced, and the national discharge standard is reached.)

1. An apparatus for absorbing an ethylene oxide off-gas, comprising:

the air inlet pipe (1), wherein an air inlet valve (11) is arranged on the air inlet pipe (1);

the condensation separation device (2) is used for liquefying and gas-liquid separating the ethylene oxide, is communicated with the air inlet pipe (1), and is internally provided with a condensation medium, and the temperature of the condensation medium is less than or equal to 10 ℃;

the catalytic absorption device (3) is used for dissolving ethylene oxide gas, the catalytic absorption device (3) comprises a catalytic absorption tank (31), a gas collection pipe (32) positioned above the catalytic absorption tank (31), and a distributor (33) arranged at the bottom of the catalytic absorption tank (31), a catalyst and water are arranged in the catalytic absorption tank (31), and an exhaust pipe of the condensation separation device (2) is introduced below the liquid level of the catalytic absorption tank (31) and communicated with the distributor (33);

the spray absorption tower set (4) is used for absorbing ethylene oxide, the spray absorption tower set (4) at least comprises an alkaline spray absorption tower (41) and an acidic spray absorption tower (42) which are communicated with each other, and the other end of the gas collecting pipe (32) is communicated below the alkaline spray absorption tower (41);

the rotational flow gas-liquid separator (5) is communicated with a discharge port of the acid spray absorption tower (42) and is used for separating gas and liquid;

the microwave photoelectrocatalysis oxidation furnace (6) is used for catalyzing the ethylene oxide waste gas into oxide and water under the action of microwave and photoelectricity and is communicated with the exhaust port of the cyclone gas-liquid separator (5);

the device comprises a chimney (9) for exhausting tail gas, wherein one end of the chimney (9) close to the microwave photoelectric catalytic oxidation furnace (6) is communicated with a centrifugal fan (8), and the other end of the centrifugal fan (8) is communicated with an exhaust port of the microwave photoelectric catalytic oxidation furnace (6).

2. An apparatus for absorbing ethylene oxide off-gas according to claim 1, wherein the condensation separation apparatus (2) comprises a shell and tube condenser (21) and a spiral plate condenser (22).

3. The ethylene oxide waste gas absorption device according to claim 2, wherein water at a liquid level of 1/4-3/5 is added into the separator of the spiral plate condenser (22), a drain pipe (23) is arranged below the spiral plate condenser (22), and a drain valve (24) is arranged on the drain pipe (23).

4. The apparatus for absorbing ethylene oxide off-gas according to claim 1, wherein the catalyst is selected from a sulfuric acid solution, or a mixed solution of a liquid alkali and ethylene glycol.

5. The ethylene oxide waste gas absorption apparatus according to claim 4, wherein the liquid levels of the catalyst and water are controlled to 1/2-4/5 of the maximum liquid level of the catalytic absorption tank (31).

6. The apparatus for absorbing ethylene oxide off-gas according to claim 1, wherein the alkaline wash solution used in the alkaline spray absorber tower (41) is a NaOH solution, and the acid wash solution used in the acidic spray absorber tower (42) is H₂SO₄And (3) solution.

7. The ethylene oxide waste gas absorption device according to claim 1, wherein the centrifugal fan (8) is provided with an activated carbon adsorption tower (7) at one end close to the chimney (9), and the other end of the activated carbon adsorption tower (7) is communicated with the air inlet of the chimney (9).

8. A method for treating an ethylene oxide off-gas by using the apparatus for absorbing an ethylene oxide off-gas according to any one of claims 1 to 6, comprising the steps of:

step one, condensation separation: cooling the ethylene oxide waste gas to below 10 ℃ through a condensation separation device (2), and liquefying the ethylene oxide to obtain ethylene oxide liquid;

step two, catalytic absorption: introducing the residual waste gas in the first step into the liquid level of a catalytic absorption tank (31) through an exhaust pipe, and carrying out bubbling treatment under the action of a distributor (33);

step three, spraying and absorbing: the waste gas collected after the catalytic absorption in the step two is subjected to alkaline spraying and acid spraying operation to absorb the ethylene oxide and other waste gas in the waste gas again;

step four, gas-liquid separation: carrying out gas-liquid separation on the excess water vapor sprayed in the third step through a cyclone gas-liquid separator (5) to obtain dry waste gas;

step five, catalytic oxidation: carrying out catalytic oxidation on the dry waste gas obtained in the step four in a microwave photoelectrocatalysis oxidation furnace (6) to obtain harmless gas;

step six, discharging: and (4) discharging the harmless gas obtained in the fifth step into the atmosphere through a chimney (9).

9. The ethylene oxide waste gas absorption device and the ethylene oxide waste gas treatment method according to claim 8, wherein the ethylene oxide liquid obtained in the first step is dissolved in water at a liquid level of 1/4-3/5 below the condensation separation device (2).

10. The apparatus for absorbing ethylene oxide off-gas and the method for treating ethylene oxide off-gas according to claim 8, wherein in the sixth step, the gas in the fifth step is discharged into the activated carbon adsorption tower (7) for physical absorption purification treatment.

Technical Field

The invention belongs to the technical field of waste gas absorption, and particularly relates to an ethylene oxide waste gas absorption device and an ethylene oxide waste gas treatment method.

Background

Ethylene Oxide (EO) is the simplest cyclic ether, belongs to the heterocyclic class of compounds, and is an important petrochemical product. It has the chemical formula of C₂H₄And O. It is a toxic carcinogen that has been used to make germicides. At present, the detergent has better penetrating power, so that the detergent is widely applied to industries such as washing, pharmacy, printing and dyeing and the like.

At present, more practical ethylene oxide is produced in each month, more than 200 tons of ethylene oxide is produced in each month, and each time an operator enters an ethylene oxide transport vehicle, the operator firstly needs to empty gas in a storage tank and reduce pressure, and then nitrogen is adopted to press ethylene oxide liquid in the ethylene oxide transport vehicle into the storage tank. However, most of the vent gas is nitrogen, the content of the ethylene oxide is about 500PPM, and the vent gas is also contained in a workshop metering tank, and the total discharge amount of two places is 300m³/hr。

The existing waste gas device can only treat the content of the ethylene oxide to 50PPM, but the current national emission standard is 5PPM, and a new technical scheme is required to reduce the emission of the ethylene oxide in the waste gas in order to reach the emission standard.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide an ethylene oxide waste gas absorption device, which reduces the discharge amount of ethylene oxide in the ethylene oxide waste gas so as to reach the national discharge standard of the content of the ethylene oxide waste gas.

In order to achieve the purpose, the invention provides the following technical scheme: an apparatus for absorbing an ethylene oxide off-gas, comprising:

the air inlet pipe is provided with an air inlet valve;

the condensation separation device is used for liquefying and gas-liquid separating the ethylene oxide, is communicated with the air inlet pipe, and is internally provided with a condensation medium, and the temperature of the condensation medium is less than or equal to 10 ℃;

the catalytic absorption device is used for dissolving ethylene oxide gas and comprises a catalytic absorption tank, a gas collecting pipe positioned above the catalytic absorption tank and a distributor arranged at the bottom of the catalytic absorption tank, wherein a catalyst and water are arranged in the catalytic absorption tank, and an exhaust pipe of the condensation separation device is introduced below the liquid level of the catalytic absorption tank and is communicated with the distributor;

the spray absorption tower group is used for absorbing ethylene oxide, the spray absorption tower group at least comprises an alkaline spray absorption tower and an acidic spray absorption tower which are communicated with each other, and the other end of the gas collecting pipe is communicated below the alkaline spray absorption tower;

the rotational flow gas-liquid separator is communicated with the discharge port of the acid spray absorption tower and is used for separating gas and liquid;

the microwave photoelectrocatalysis oxidation furnace is used for catalyzing the ethylene oxide waste gas into oxide and water under the action of microwave and photoelectricity and is communicated with the exhaust port of the rotational flow gas-liquid separator;

and the chimney is used for exhausting tail gas, one end of the chimney close to the microwave photoelectric catalytic oxidation furnace is communicated with a centrifugal fan, and the other end of the centrifugal fan is communicated with an exhaust port of the microwave photoelectric catalytic oxidation furnace.

By adopting the technical scheme, the temperature of the ethylene oxide waste gas (namely the waste gas) entering through the air inlet pipe can be effectively reduced to be below 10 ℃ under the action of the condensation separation device, and at the moment, the ethylene oxide is changed into liquid ethylene oxide from gas state at the temperature because the boiling point of the ethylene oxide is 10.4 ℃. In this case, a large portion of the ethylene oxide is removed from the ethylene oxide off-gas, which contributes to a reduction in the ethylene oxide content of the ring off-gas. And then the gas after the condensation separation treatment is subjected to catalytic absorption, so that the ethylene oxide in the waste gas can be further absorbed by catalytic liquid (namely a mixture of the catalyst and water) in the catalytic absorption device, and the content of the ethylene oxide in the waste gas is further reduced.

Then the waste gas after catalytic absorption is discharged into an alkaline spray absorption tower, under the action of alkaline liquor, the acid gas in the waste gas can be absorbed by the alkaline liquor, and then the waste gas is discharged into an acid spray absorption tower and subjected to acid liquor treatmentUnder the action, alkaline gas in the waste gas can be absorbed by the acid liquor, and meanwhile, the acid liquor has a certain catalysis effect, so that water in the spraying absorption tower group can absorb ethylene oxide in the waste gas more quickly and comprehensively, and the content of ethylene oxide in the waste gas can be further reduced. Because the waste gas after the spraying operation contains a large amount of moisture, when the microwave and photoelectric treatment is directly carried out, the moisture in the waste gas can influence the effective proceeding of the microwave and photoelectric treatment, therefore, a cyclone gas-liquid separator is additionally arranged before the microwave treatment, the excessive moisture in the waste gas can be effectively removed under the action of the cyclone gas-liquid separator, the waste gas passing through the cyclone gas-liquid separator enters the microwave photoelectric catalytic oxidation furnace, the waste gas such as ethylene oxide and the like can be catalyzed into oxide and water (harmless gas) under the action of the microwave and the photoelectric, and the ethylene oxide generates CO₂And H₂O (water vapor) is changed into harmless gas and can be discharged. And finally, under the action of a centrifugal fan, exhausting the carbon dioxide and water (water vapor) from the chimney. Therefore, the effective absorption of the ethylene oxide waste gas can be completed by adopting the similar operation to reduce the content of the ethylene oxide in the waste gas, thereby reaching the emission standard of the ethylene oxide waste gas.

Further, the condensation and separation device comprises a tube array condenser and a spiral plate condenser.

Furthermore, 1/4~3/5 liquid level water is added to the separator of spiral plate condenser, the below of spiral plate condenser is equipped with the drain pipe, be equipped with drainage valve on the drain pipe.

Through adopting above-mentioned technical scheme, fill the water of 1/4~3/5 liquid level in the separator of spiral plate condenser, because ethylene oxide is easily dissolved in water, liquefied ethylene oxide is through dissolving in water this moment, can accomplish the effective separation between ethylene oxide and other waste gases through regularly discharging waste water from this. Meanwhile, the existence of water can also play a role in liquid sealing on the ethylene oxide waste gas, and the discharge of the ethylene oxide from a drain pipe is reduced, so that the effect of gas-liquid separation is achieved.

Further, the catalyst is selected from a sulfuric acid solution or a mixed solution of liquid alkali and glycol.

Further, the liquid levels of the catalyst and water are controlled to be 1/2-4/5 of the maximum liquid level of the catalytic absorption tank.

By adopting the technical scheme, the sulfuric acid is common catalytic liquid (namely a mixture of the catalyst and water) for absorbing the ethylene oxide, and the absorption rate of the ethylene oxide can be improved under the action of the catalytic liquid, so that the content of the ethylene oxide in the waste gas can be reduced.

Further, the alkaline washing solution adopted in the alkaline spray absorption tower is NaOH solution, and the acid washing solution of the acidic spray absorption tower is H₂SO₄And (3) solution.

Further, the NaOH solution is optimized to be 1-15 wt% of NaOH solution, and the H2SO4 solution is optimized to be 1-15 wt% of H₂SO₄And (3) solution.

By adopting the technical scheme, the NaOH solution is the alkali wash liquid of a common alkali spray absorption tower, and can absorb the acid gas (the acid gas refers to the gas which can react with alkali to generate salt, such as HCl and H) in the ethylene oxide waste gas₂S, etc.); and H₂SO₄The solution is a commonly used acid washing solution of an acid absorption tower, and can absorb alkaline gas (such as NH) in ethylene oxide waste gas₃Other organic ammonia).

Furthermore, an active carbon adsorption tower is installed at one end, close to the chimney, of the centrifugal fan, and the other end of the active carbon adsorption tower is communicated with the air inlet of the chimney.

By adopting the technical scheme, the active carbon adsorption tower mainly contains the active carbon adsorption filter element, and under the action of the active carbon adsorption filter element, the active carbon adsorption tower can effectively absorb odor, natural and synthetic dissolved organic matters, micro-pollutants and the like in waste gas through the physical adsorption effect of the active carbon. Thereby effectively reducing the discharge amount of harmful gas in the chimney in the later period and greatly improving the discharge quality.

The invention provides the following technical scheme: a method for treating ethylene oxide waste gas by using an ethylene oxide waste gas absorption device comprises the following operation steps:

step one, condensation separation: cooling the ethylene oxide waste gas to below 10 ℃ through a condensation separation device, and liquefying the ethylene oxide to obtain ethylene oxide liquid;

step two, catalytic absorption: leading the residual waste gas in the first step into the liquid level of the catalytic absorption tank through an exhaust pipe, and carrying out bubbling treatment under the action of a distributor;

step three, spraying and absorbing: the waste gas collected after the catalytic absorption in the step two is subjected to alkaline spraying and acid spraying operation to absorb the ethylene oxide and other waste gas in the waste gas again;

step four, gas-liquid separation: carrying out gas-liquid separation on the excess water vapor sprayed in the third step through a cyclone gas-liquid separator to obtain dry waste gas;

step five, catalytic oxidation: carrying out catalytic oxidation on the dried waste gas obtained in the step four by using a microwave photoelectrocatalysis oxidation furnace to obtain harmless gas;

step six, discharging: and (4) discharging the harmless gas obtained in the fifth step into the atmosphere through a chimney.

Further, dissolving the ethylene oxide liquid obtained in the step one in water at the liquid level of 1/4-3/5 below the condensation separation device.

Further, in the sixth step, the gas in the fifth step is discharged into an activated carbon adsorption tower to be physically absorbed and purified.

By adopting the technical scheme, the content of the ethylene oxide in the ethylene oxide waste gas (namely the waste gas) can be effectively reduced by liquefying the ethylene oxide after condensation separation treatment, and then the content of the ethylene oxide in the waste gas can be further reduced by the absorption of the catalyst (sulfuric acid). And then under the respective spraying action of the alkaline washing solution and the acid washing solution, the content of harmful gas in the waste gas can be reduced again, and then under the action of the cyclone gas-liquid separator, redundant water in the waste gas is discharged, so that the later catalytic oxidation operation is facilitated. Then the harmless gas can be obtained after catalytic oxidation by a microwave photoelectrocatalysis oxidation furnace.

In conclusion, the invention has the following beneficial effects:

1. the invention reduces the discharge amount of the ethylene oxide in the ethylene oxide waste gas, and reaches the national discharge standard of the content of the ethylene oxide waste gas;

2. optimally, water with the liquid level of 1/4-3/5 is filled in a separator of the spiral plate condenser, and because ethylene oxide is easily dissolved in water, the liquefied ethylene oxide is dissolved in water, so that the effective separation of ethylene oxide and other waste gases can be completed by regularly discharging waste water; meanwhile, the existence of water can also play a role in liquid sealing on the ethylene oxide waste gas, so that the discharge of the ethylene oxide from a drain pipe is reduced, and the effect of gas-liquid separation is achieved.

Drawings

FIG. 1 is a schematic structural view of example 2 in an ethylene oxide off-gas absorption apparatus.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.