CN215855122U - Device for removing free chlorine in waste sulfuric acid - Google Patents

Abstract

The utility model discloses a device for removing free chlorine in waste sulfuric acid, wherein an inlet of a dilute acid storage tank (1) is communicated with a dilute acid storage device (10), an outlet of the dilute acid storage tank (1) and an outlet of a circulating storage tank (2) are communicated with an input port of a dechlorination circulating pump (3), a nitrogen storage chamber (11) is arranged at the bottom of a dechlorination tower (4), a sampling port (12) of the dechlorination tower (4) is communicated with the top of the circulating storage tank (2), an output port of the dechlorination circulating pump (3) is respectively communicated with the dechlorination tower (4), a finished product dilute acid tank (8), the dilute acid storage tank (1) and the circulating storage tank (2) through a branch I, a branch II, a branch III and a branch IV, an air outlet of a dechlorination blower (5) is communicated with an air inlet of the dechlorination tower (4), an outlet at the top of the dechlorination tower (4) is communicated with an input port I of a water flow ejector (16), the outlet of the absorption circulating pump (7) is communicated with the input port II of the water flow ejector (16).

Description

Device for removing free chlorine in waste sulfuric acid

Technical Field

The utility model relates to a device for removing free chlorine in waste sulfuric acid.

Background

In the current chlorine treatment process of the ionic membrane caustic soda device, about 7000 tons of waste sulfuric acid with the concentration of about 75% is generated every year, and the waste sulfuric acid dissolves chlorine gas with the concentration of 1100PPm, chloride ions with the concentration of 470PPm, and a small amount of suspended matters and mechanical impurities. The waste sulfuric acid containing more than 1000PPm of chlorine is treated as dangerous waste according to the relevant standard of the ministry of ecology and the national development and reform Committee < dangerous waste records >, so that 140 ten thousand yuan of waste sulfuric acid is subsidized every year for treating factories, and the part of waste sulfuric acid is treated and recycled. At present, the concentration and purification technology is generally adopted at home and abroad to treat dilute sulfuric acid containing impurities, namely, the low-concentration waste sulfuric acid after impurity removal is concentrated into high-concentration commodity acid by different methods for recycling. The applied concentration technology mainly comprises a high-temperature combustion concentration technology, a vacuum concentration technology and a multi-effect evaporation concentration technology. But the equipment investment is huge, the operation cost is high, and the applicability is poor.

Disclosure of Invention

The device for removing the free chlorine in the waste sulfuric acid provided by the utility model adopts a nitrogen blowing method to remove the free chlorine in the waste sulfuric acid, and has the advantages of simple process, simple and convenient operation, low investment, relatively low operation cost, no secondary pollution, simple removal operation and good removal effect.

The utility model adopts the following technical scheme: a device for removing free chlorine in waste sulfuric acid comprises a dilute acid storage tank, a circulating storage tank, a dechlorination circulating pump, a dechlorination tower, a dechlorination blower, a chlorine absorption circulating tank, an absorption circulating pump, a finished product dilute acid tank and a finished product circulating pump, wherein an inlet of the dilute acid storage tank is communicated with a dilute acid storage device, an outlet of the dilute acid storage tank and an outlet of the circulating storage tank are communicated with an input port of the dechlorination circulating pump, a nitrogen storage chamber is arranged at the bottom of the dechlorination tower, a sampling port is also arranged at the bottom of the dechlorination tower and is communicated with the top of the circulating storage tank, an output port of the dechlorination circulating pump is divided into a branch I, a branch II, a branch III and a branch IV, an output port of the dechlorination circulating pump is communicated with an inlet on tower side face, an output port of the dechlorination circulating pump is communicated with an inlet of the finished product dilute acid tank, and an outlet of the finished product circulating pump is connected with the finished product circulating pump, the branch III is communicated with a backflow port of the dilute acid storage tank through an output port of the dechlorination circulating pump, the branch IV is communicated with a backflow port of the circulating storage tank through an output port of the dechlorination circulating pump, an air outlet of the dechlorination air blower is communicated with an air inlet of the dechlorination tower through an air filter, a silencer is arranged on the dechlorination air blower, an outlet at the top of the dechlorination tower is communicated with an input port I of the water flow ejector, a liquid outlet at the lower part of the side surface of the chlorine absorption circulating tank is communicated with an inlet of the absorption circulating pump, and an outlet of the absorption circulating pump is communicated with an input port II of the water flow ejector.

The bottom of the dilute acid storage tank is connected with a blow-down valve I, and a valve I is arranged between an outlet of the dilute acid storage tank and an input port of the dechlorination circulating pump. And a valve II is arranged between the outlet of the circulating storage tank and the input port of the dechlorination circulating pump.

And a valve III is arranged between the output port of the dechlorination circulating pump and the inlet on the side surface of the dechlorination tower.

And a valve IV is arranged between the output port of the dechlorination circulating pump and the inlet of the finished product dilute acid tank.

And a valve V is arranged between the output port of the dechlorination circulating pump and the return port of the dilute acid storage tank. And a valve VI is arranged between the output port of the dechlorination circulating pump and the return port of the circulating storage tank. And a valve VII is arranged between a liquid outlet at the lower part of the side surface of the chlorine absorption circulating groove and an inlet of the absorption circulating pump, and a blow-down valve II is arranged at the bottom of the chlorine absorption circulating groove.

The utility model has the following beneficial effects: after the technical scheme is adopted, the device provided by the utility model has the advantages that the operation is stable, the device is economical and feasible, and the free chlorine in the waste sulfuric acid is removed, so that the aim of recycling is fulfilled. The utility model can be used for circularly blowing the waste sulfuric acid containing chlorine by adopting nitrogen or compressed air to remove free chlorine, and circularly absorbing the blown free chlorine by using alkali. The blowing time of the utility model is determined by the amount of the waste sulfuric acid and the flow of the nitrogen, 15 tons of waste sulfuric acid is treated, the flow of the nitrogen is 3.5m3/h, the blowing is generally carried out for 8 hours, the free chlorine in the waste acid can be reduced to below 50PPm, thus avoiding the blackening of the sulfuric acid caused by overlong time and the carbonization of the sulfuric acid caused by a small amount of oil carried in the nitrogen. When the pH value of the absorption liquid reaches 7-8 after detection, the dilute alkali solution is recycled, so that the air pollution is reduced to the minimum. The method for removing the free chlorine in the waste sulfuric acid by adopting the nitrogen blowing method has the advantages of simple process, simple and convenient operation, low investment, relatively low operation cost and no secondary pollution. After treatment, the free chlorine in the waste sulfuric acid is reduced to below 50PPm from 1100PPm, and the cost is saved.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Detailed Description

In figure 1, the utility model provides a device for removing free chlorine in waste sulfuric acid, which comprises a dilute acid storage tank 1, a circulating storage tank 2, a dechlorination circulating pump 3, a dechlorination tower 4, a dechlorination blower 5, a chlorine absorption circulating tank 6, an absorption circulating pump, a finished product dilute acid tank 8 and a finished product circulating pump 9, wherein an inlet of the dilute acid storage tank 1 is communicated with a dilute acid storage device 10, an outlet of the dilute acid storage tank 1 and an outlet of the circulating storage tank 2 are communicated with an inlet of the dechlorination circulating pump 3, a nitrogen storage chamber 11 is arranged at the bottom of the dechlorination tower 4, a sampling port 12 is also arranged at the bottom of the dechlorination tower 4, the sampling port 12 is communicated with the top of the circulating storage tank 2, an outlet of the dechlorination circulating pump 3 is divided into a branch I, a branch II, a branch III and a branch IV, an outlet of the dechlorination circulating pump 3 is communicated with an inlet on tower 4 side, an outlet of the branch II is communicated with an inlet of the finished product dilute acid tank 8, a finished product circulating pump 9 is connected with an outlet of a finished product dilute acid tank 8, a branch III is formed by communicating an output port of a dechlorination circulating pump 3 with a backflow port of a dilute acid storage tank 1, a branch IV is formed by communicating an output port of the dechlorination circulating pump 3 with a backflow port of a circulating storage tank 2, an air outlet of a dechlorination air blower 5 is communicated with an air inlet of a dechlorination tower 4 through an air filter 14, a silencer 15 is arranged on the dechlorination air blower 5, an outlet at the top of the dechlorination tower 4 is communicated with an input port I of a water flow ejector 16, a liquid outlet at the lower part of the side surface of a chlorine absorption circulating tank 6 is communicated with an inlet of the absorption circulating pump 7, an outlet of the absorption circulating pump 7 is communicated with an input port II of the water flow ejector 16, a blow-down valve I17 is connected with the bottom of the dilute acid storage tank 1, a valve I18 is arranged between the outlet of the dilute acid storage tank 1 and the input port of the dechlorination circulating pump 3, a valve II 19 is arranged between the outlet of the circulating storage tank 2 and the input port of the dechlorination circulating pump 3, dechlorination circulating pump 3's delivery outlet and the import of dechlorination tower 4 side between be equipped with valve III 20, dechlorination circulating pump 3's delivery outlet and finished product dilute acid tank 8's import between be equipped with valve IV 21, dechlorination circulating pump 3's delivery outlet and dilute acid storage tank 1's backward flow mouth between be equipped with valve V22, dechlorination circulating pump 3's delivery outlet and circulation storage tank 2's backward flow mouth between be equipped with valve VI 23, chlorine absorption circulating tank 6's the liquid outlet of side lower part and absorption circulating pump 7's import between be equipped with valve VII 24, chlorine absorption circulating tank 6's bottom is equipped with blowoff valve II 13.

The utility model discloses a method for removing free chlorine in waste sulfuric acid by using a device, which comprises the following steps: firstly, drying 75% of waste sulfuric acid in a dilute acid storage device 10 by using chlorine, and pumping the dried waste sulfuric acid into a dilute acid storage tank 1 or a circulating storage tank 2 by using a pump for storage; secondly, pumping part of the dried waste sulfuric acid stored in the dilute acid storage tank 1 or the circulating storage tank 2 into a finished product dilute acid tank 8 directly through a dechlorination circulating pump 3, inputting the other part of the waste sulfuric acid into a dechlorination tower 4 through the dechlorination circulating pump 3, spraying the waste sulfuric acid input into the dechlorination tower 4 to be in reverse contact with nitrogen entering from the lower part of the dechlorination tower 4, introducing the nitrogen in a purging mode, wherein the purging time is determined by the amount of the waste sulfuric acid and the flow of the nitrogen, when 15 tons of waste sulfuric acid are treated, the flow of the nitrogen is 3.5m3/h, and the purging time is 8 hours, so that free chlorine in the waste sulfuric acid can be reduced to below 50PPm,

chlorine in the waste sulfuric acid is removed after reverse contact, and qualified dilute sulfuric acid after dechlorination is discharged into a circulating storage tank 2 through a sampling port 12 to be directly sold or prepared into 93 percent acid for self use; and step three, feeding the chlorine gas removed in the step two into a water flow ejector 16, pumping the dilute alkali solution discharged from the chlorine gas absorption circulating tank 6 into the water flow ejector 16 through an absorption circulating pump 7, mixing the chlorine gas with the chlorine gas, and then spraying the mixed solution into the chlorine gas absorption circulating tank 6 to absorb the chlorine gas, and performing recovery treatment when the pH value of the dilute alkali solution reaches 7-8 by detection, so that the air pollution is reduced to the minimum. In the utility model, the higher the temperature of the waste sulfuric acid is, the better the dechlorination effect is, but the requirements on the material of the equipment are higher, so the comprehensive consideration is to select the normal temperature.

Claims (8)

1. A device for removing free chlorine in waste sulfuric acid is characterized by comprising a dilute acid storage tank (1), a circulating storage tank (2), a dechlorination circulating pump (3), a dechlorination tower (4), a dechlorination air blower (5), a chlorine gas absorption circulating tank (6), an absorption circulating pump (7), a finished product dilute acid tank (8) and a finished product circulating pump (9), wherein an inlet of the dilute acid storage tank (1) is communicated with a dilute acid storage device (10), an outlet of the dilute acid storage tank (1) and an outlet of the circulating storage tank (2) are communicated with an inlet of the dechlorination circulating pump (3), a nitrogen storage chamber (11) is arranged at the bottom of the dechlorination tower (4), a sampling port (12) is also arranged at the bottom of the dechlorination tower (4), the sampling port (12) is communicated with the top of the circulating storage tank (2), an outlet of the dechlorination circulating pump (3) is divided into a branch I, a branch II, a branch III and a branch IV, the branch I is communicated with an inlet on the side surface of the dechlorination tower (4) through an output port of the dechlorination circulating pump (3), the branch II is communicated with an inlet of the finished product dilute acid tank (8) through an output port of the dechlorination circulating pump (3), the outlet of the finished product dilute acid tank (8) is connected with the finished product circulating pump (9), the branch III is communicated with a backflow port of the dilute acid storage tank (1) through an output port of the dechlorination circulating pump (3), the branch IV is communicated with a backflow port of the circulating storage tank (2) through an output port of the dechlorination circulating pump (3), an air outlet of the dechlorination blower (5) is communicated with an air inlet of the dechlorination tower (4) through an air filter (14), a silencer (15) is arranged on blower (5), an outlet on the top of the dechlorination tower (4) is communicated with an input port I of a water flow ejector (16), and a liquid outlet on port on side lower part of the chlorine absorption circulating tank (6) is communicated with an inlet of the absorption circulating pump (7), the outlet of the absorption circulating pump (7) is communicated with the input port II of the water flow ejector (16).

2. The device for removing the free chlorine in the waste sulfuric acid as claimed in claim 1, wherein the bottom of the dilute acid storage tank (1) is connected with a blowdown valve I (17), and a valve I (18) is arranged between the outlet of the dilute acid storage tank (1) and the input of the dechlorination circulating pump (3).

3. The apparatus for removing free chlorine from waste sulfuric acid as claimed in claim 1, wherein a valve II (19) is arranged between the outlet of the circulating storage tank (2) and the input of the dechlorination circulating pump (3).

4. The apparatus for removing free chlorine from waste sulfuric acid as claimed in claim 1, wherein a valve III (20) is provided between the output of the dechlorination circulating pump (3) and the inlet of the side of the dechlorination tower (4).

5. The apparatus for removing free chlorine from waste sulfuric acid as claimed in claim 1, wherein a valve IV (21) is arranged between the output of the dechlorination circulating pump (3) and the inlet of the finished product dilute acid tank (8).

6. The device for removing the free chlorine in the waste sulfuric acid as claimed in claim 1, wherein a valve V (22) is arranged between the output port of the dechlorination circulating pump (3) and the return port of the dilute acid storage tank (1).

7. The device for removing the free chlorine in the waste sulfuric acid as claimed in claim 1, wherein a valve VI (23) is arranged between the output port of the dechlorination circulating pump (3) and the return port of the circulating storage tank (2).

8. The device for removing the free chlorine in the waste sulfuric acid as claimed in claim 1, wherein a valve VII (24) is arranged between a liquid outlet at the lower part of the side surface of the chlorine gas absorption circulating tank (6) and an inlet of the absorption circulating pump (7), and a blow-down valve II (13) is arranged at the bottom of the chlorine gas absorption circulating tank (6).

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