Treatment system for black powder synthesis byproduct hydrogen sulfide

Abstract

The utility model discloses a treatment system for a black powder synthesis byproduct hydrogen sulfide, and belongs to the technical field of waste gas treatment. Comprising a buffer tank, a spray thrower in front of the tower, a first-stage shared circulating tank, a second-stage shared circulating tank, a third-stage alkaline washing tower, a fourth-stage alkaline washing tower and a vacuum injection unit which are sequentially connected, and each of the first-stage shared circulating tank and the second-stage shared circulating tank consists of a falling film absorber, an alkaline washing tower, a circulating pump and a pipeline; and the third-stage alkaline washing tower and the fourth-stage alkaline washing tower are connected with coolers and circulating pumps. According to the utility model, the zinc waste residue is recycled, so that the problem of environmental pollution caused by stacking and storage of the zinc waste residue is reduced. According to the utility model, the falling film absorber and multi-stage absorption are arranged, so that the concentration of sodium sulfide reaches the quality index, the use amount of sodium hydroxide is reduced, and the economic benefit is effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of waste gas treatment, in particular to a treatment system for hydrogen sulfide, a by-product of black medicine synthesis. Background Art

[0002] The by-product of the mineral processing agent ammonium butyl black medicine is hydrogen sulfide during the synthesis process. Hydrogen sulfide is a gas with a rotten egg smell and a higher density than air. When the density of hydrogen sulfide in the air is greater than 1.5 mg / m 3 However, when the concentration is 200 times higher than the above concentration, the human olfactory nerves will be paralyzed and the person will not be able to smell it. Hydrogen sulfide is a neurotoxin that can invade the respiratory tract and cause poisoning. Low concentrations of hydrogen sulfide can cause stinging eyes, tearing, vomiting, and even symptoms such as pulmonary edema and pneumonia; high concentrations of hydrogen sulfide can cause coma or even suffocation; acute poisoning can also cause headaches and decreased intelligence.

[0003] Hydrogen sulfide can be absorbed by sodium hydroxide aqueous solution to generate sodium sulfide, which can be sold as a by-product. However, due to the inappropriate choice of the current absorption process, the absorption efficiency is low, which in turn causes the mass concentration of sodium sulfide to fail to meet the quality index range, and the sodium sulfide cannot be sold normally. In order to further improve the absorption efficiency and optimize the absorption process, the bubbling absorption tower used in the original absorption process is changed to falling film absorption tower absorption, which not only makes the sodium sulfide concentration reach the quality index, but also reduces the use of sodium hydroxide, effectively improving economic benefits. Summary of the invention

[0004] The purpose of the utility model is to provide a treatment system for hydrogen sulfide, a byproduct of black medicine synthesis, which not only makes the concentration of sodium sulfide reach the quality index, but also reduces the amount of sodium hydroxide used, effectively improving economic benefits, thereby solving the problems raised in the above background technology.

[0005] The technical solution adopted by the utility model is as follows:

[0006] A treatment system for hydrogen sulfide, a byproduct of black medicine synthesis, comprises a buffer tank, a tower front sprayer, a primary common circulation tank, a secondary common circulation tank, a tertiary alkali washing tower, a quaternary alkali washing tower and a vacuum jet unit connected in sequence, wherein the primary common circulation tank and the secondary common circulation tank are both composed of a falling film absorber, an alkali washing tower, a circulation pump and a pipeline, and the tertiary alkali washing tower and the quaternary alkali washing tower are both connected with an external cooler and a circulation pump. A defoaming layer is provided at the top of each stage of the alkali washing tower, and a defoamer is provided at the exhaust gas outlet of the vacuum jet unit.

[0007] The bottom liquid outlets of the alkali washing towers of the first-level common circulation tank and the second-level common circulation tank are respectively connected with the absorption liquid inlet of the alkali washing tower of the same level and the absorption liquid inlet of the falling film absorber of the same level through a circulation pump and a pipeline in two ways, the gas outlet of the falling film absorber is connected with the gas inlet of the alkali washing tower of the same level, the gas inlet of the falling film absorber of the second-level common circulation tank is connected with the gas outlet of the alkali washing tower of the first-level common circulation tank, and the gas inlet of the falling film absorber of the first-level common circulation tank is connected with the gas outlet of the tower front sprayer.

[0008] The bottom liquid outlets of the tertiary alkali washing tower and the quaternary alkali washing tower are connected to the inlet of the cooler through a circulation pump, the outlet of the cooler is connected to the absorption liquid inlet of the alkali washing tower of the same level through a pipeline, the gas inlet of the tertiary alkali washing tower is connected to the gas outlet of the alkali washing tower of the secondary shared circulation tank, the gas outlet of the tertiary alkali washing tower is connected to the gas inlet of the quaternary alkali washing tower, and the gas outlet of the quaternary alkali washing tower is connected to the gas inlet of the vacuum jet unit.

[0009] The method for treating a treatment system of hydrogen sulfide, a by-product of black medicine synthesis, comprises the following steps: firstly, collecting hydrogen sulfide waste gas and entering a jacketed buffer for cooling; the hydrogen sulfide waste gas after cooling enters a tower front sprayer and a first-level common circulation tank to be washed with a sodium hydroxide solution to generate 15%-30% sodium sulfide; the waste gas after the first-level washing enters a second-level common circulation tank to be washed with a sodium hydroxide solution to generate about 5-15% sodium sulfide; the waste gas after the second-level washing enters a third-level alkali washing tower to be washed with sodium hydroxide to generate less than 7% dilute sodium sulfide; the waste gas after the third-level washing enters a fourth-level alkali washing tower to be washed with sodium hydroxide to generate less than 3% dilute sodium sulfide; the waste gas after the fourth-level washing enters a vacuum jet unit, and an acid mist demister and demister is added at the waste gas outlet of the vacuum jet unit to ensure that the hydrogen sulfide acid mist is captured;

[0010] The circulating liquid of each stage enters the tower body from the upper part of the absorber and is evenly sprayed into the falling film absorber through the liquid release device. The airflow from top to bottom and the descending absorbent are fully in contact with each other in the falling film absorber with a very large specific surface area, which enhances the absorption effect of the absorbent and makes the concentration of acid mist dissolved in the absorbent in the airflow from top to bottom lower and lower. When it reaches the bottom of the tower, it meets the washing requirements and enters the next stage of treatment equipment.

[0011] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0012] 1. The falling film absorber provided in the utility model absorbs the waste gas by the absorption liquid flowing downstream, and at the same time, the heat generated in the absorption process is taken away by the circulating cooling water through the shell and tube heat exchanger in the shell to achieve efficient absorption, and the absorption liquid circulates through the tank until the required concentration is reached before the absorption liquid is replaced. In the falling film absorber, the liquid falls along the wall under the action of gravity to form a thin film and is contacted and absorbed in parallel with the gas. The liquid film falling along the wall can be formed on a flat surface or on the inner and outer walls of a circular tube, generally in a circular tube, and has the following characteristics: the gas film and the liquid film do not penetrate each other, the pressure drop of the equipment is small, and a higher gas load is allowed; the falling film is very thin and can produce special fluctuations on the surface of the film, and the back-mixing of the gas phase and the liquid film is small, the heat and mass transfer efficiency is high, and the total amount of fluid transfer generated per unit energy consumption is large; the liquid film falling along the wall can be cooled by the intermediate wall, which is suitable for absorption processes with high thermal effects, and the reaction process can be carried out at a nearly isothermal condition;

[0013] 2. In the present invention, since hydrogen sulfide gas releases a large amount of heat during the process of dissolving in the circulating liquid and reacting, the heat accumulates in the circulating liquid system and causes the circulating liquid temperature to rise. When the circulating liquid temperature reaches 35°C, the absorption effect of the circulating liquid will be greatly deteriorated. However, the present invention controls the circulating liquid temperature below 15°C by setting a corresponding falling film absorber and an external cooler;

[0014] 3. The utility model adopts multi-stage absorption to treat the high-concentration hydrogen sulfide by-product; in addition, a defoaming layer is arranged at the top of each stage of the alkali washing tower and an acid mist demisting and defoaming device is arranged at the exhaust gas outlet of the vacuum injection unit, so as to remove the hydrogen sulfide acid mist and part of the liquid foam entrainment, ensuring that the hydrogen sulfide acid mist is captured.

[0015] In summary, the utility model, by providing a falling film absorber and multi-stage absorption, not only makes the sodium sulfide concentration reach the quality index, but also reduces the use of sodium hydroxide, effectively improving the economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the utility model;

[0017] Figure 2 It is a structural schematic diagram of a primary combined circulation tank or a secondary combined circulation tank of the utility model;

[0018] Figure 3 It is a schematic diagram of the structure of a three-stage alkali washing tower or a four-stage alkali washing tower of the utility model. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Generally, the components of the embodiment of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Example 1

[0022] like Figure 1-3 The present embodiment provides a treatment system for hydrogen sulfide, a by-product of black medicine synthesis, comprising a buffer tank, a front-tower sprayer, a primary common circulation tank, a secondary common circulation tank, a tertiary alkali washing tower, a quaternary alkali washing tower and a vacuum jet unit connected in sequence, wherein the primary common circulation tank and the secondary common circulation tank are both composed of a falling film absorber, an alkali washing tower, a circulation pump and a pipeline, and the tertiary alkali washing tower and the quaternary alkali washing tower are both connected with a cooler and a circulation pump.

[0023] The top of each level of the alkali washing tower is provided with a defoaming layer, and the exhaust gas outlet of the vacuum jet unit is provided with an acid mist defoamer and demister, so as to remove the hydrogen sulfide acid mist and part of the liquid foam entrainment, and ensure that the hydrogen sulfide acid mist is captured.

[0024] The bottom liquid outlets of the alkali washing towers of the first-level common circulation tank and the second-level common circulation tank are respectively connected with the absorption liquid inlet of the alkali washing tower of the same level and the absorption liquid inlet of the falling film absorber of the same level through a circulation pump and a pipeline in two ways, the gas outlet of the falling film absorber is connected with the gas inlet of the alkali washing tower of the same level, the gas inlet of the falling film absorber of the second-level common circulation tank is connected with the gas outlet of the alkali washing tower of the first-level common circulation tank, and the gas inlet of the falling film absorber of the first-level common circulation tank is connected with the gas outlet of the tower front sprayer.

[0025] The bottom liquid outlets of the tertiary alkali washing tower and the quaternary alkali washing tower are connected to the inlet of the cooler through a circulation pump, the outlet of the cooler is connected to the absorption liquid inlet of the alkali washing tower of the same level through a pipeline, the gas inlet of the tertiary alkali washing tower is connected to the gas outlet of the alkali washing tower of the secondary shared circulation tank, the gas outlet of the tertiary alkali washing tower is connected to the gas inlet of the quaternary alkali washing tower, and the gas outlet of the quaternary alkali washing tower is connected to the gas inlet of the vacuum jet unit.

[0026] The method for treating a treatment system of hydrogen sulfide, a by-product of black medicine synthesis, comprises the following steps: firstly, collecting hydrogen sulfide waste gas and entering a jacketed buffer for cooling; the hydrogen sulfide waste gas after cooling enters a tower front sprayer and a first-level common circulation tank to be washed with a sodium hydroxide solution to generate 15%-30% sodium sulfide; the waste gas after the first-level washing enters a second-level common circulation tank to be washed with a sodium hydroxide solution to generate about 5-15% sodium sulfide; the waste gas after the second-level washing enters a third-level alkali washing tower to be washed with sodium hydroxide to generate less than 7% dilute sodium sulfide; the waste gas after the third-level washing enters a fourth-level alkali washing tower to be washed with sodium hydroxide to generate less than 3% dilute sodium sulfide; the waste gas after the fourth-level washing enters a vacuum jet unit, and an acid mist demister and demister is added at the waste gas outlet of the vacuum jet unit to ensure that the hydrogen sulfide acid mist is captured;

[0027] The circulating liquid of each stage enters the tower body from the upper part of the absorber and is evenly sprayed into the falling film absorber through the liquid release device. The airflow from top to bottom and the descending absorbent are fully in contact in the falling film absorber with a very large specific surface area, which enhances the absorption effect of the absorbent and makes the concentration of acid mist dissolved in the absorbent in the airflow from top to bottom lower and lower. When it reaches the bottom of the tower, it meets the washing requirements and enters the next stage of treatment equipment (UV photocatalytic equipment) and finally meets the emission standards.

[0028] The falling film absorber provided in the utility model absorbs the waste gas by the absorption liquid flowing downstream, and at the same time, the heat generated in the absorption process is taken away by the circulating cooling water through the shell and tube heat exchanger in the shell to realize efficient absorption, and the absorption liquid circulates through the tank until the required concentration is reached before the absorption liquid is replaced. In the falling film absorber, the liquid falls along the wall under the action of gravity to form a thin film and is contacted and absorbed with the gas in parallel flow. The liquid film falling along the wall can be formed on the flat surface or the inner and outer walls of the circular tube, generally formed in the circular tube, and has the following characteristics: the gas film and the liquid film do not penetrate each other, the pressure drop of the equipment is small, and a higher gas load is allowed; the falling film is very thin and can produce special fluctuations on the surface of the film, and the back mixing of the gas phase and the liquid film is small, the heat and mass transfer efficiency is high, and the total amount of fluid transfer generated per unit energy consumption is large; the liquid film falling along the wall can be cooled by the intermediate wall, which is suitable for absorption processes with high thermal effects, and the reaction process can be carried out at a nearly isothermal condition.

[0029] In the present invention, since hydrogen sulfide gas releases a large amount of heat during the process of dissolving in the circulating liquid and reacting, the heat accumulates in the circulating liquid system and causes the circulating liquid temperature to rise. When the circulating liquid temperature reaches 35°C, the absorption effect of the circulating liquid will be greatly deteriorated. The present invention controls the circulating liquid temperature below 15°C by setting a corresponding falling film absorber and an external cooler.

Claims

1. A system for treating hydrogen sulfide, a by-product of black medicine synthesis, characterized in that: The utility model comprises a buffer tank, a pre-tower sprayer, a first-stage common circulation tank, a second-stage common circulation tank, a third-stage alkali washing tower, a fourth-stage alkali washing tower and a vacuum jet unit which are connected in sequence. The first-stage common circulation tank and the second-stage common circulation tank are both composed of a falling film absorber, an alkali washing tower, a circulation pump and a pipeline. The third-stage alkali washing tower and the fourth-stage alkali washing tower are both connected with a cooler and a circulation pump.

2. A system for treating hydrogen sulfide, a by-product of black medicine synthesis according to claim 1, characterized in that: A defoaming layer is arranged at the top of each stage of the alkali washing tower, and a defoamer is arranged at the exhaust gas outlet of the vacuum jet unit.

3. A system for treating hydrogen sulfide, a by-product of black medicine synthesis, according to claim 1, characterized in that: The bottom liquid outlets of the alkali washing towers of the first-level common circulation tank and the second-level common circulation tank are respectively connected with the absorption liquid inlet of the alkali washing tower of the same level and the absorption liquid inlet of the falling film absorber of the same level through a circulation pump and a pipeline in two ways, the gas outlet of the falling film absorber is connected with the gas inlet of the alkali washing tower of the same level, the gas inlet of the falling film absorber of the second-level common circulation tank is connected with the gas outlet of the alkali washing tower of the first-level common circulation tank, and the gas inlet of the falling film absorber of the first-level common circulation tank is connected with the gas outlet of the tower front sprayer.

4. A treatment system for hydrogen sulfide, a by-product of black medicine synthesis according to claim 1, characterized in that: The bottom liquid outlets of the tertiary alkali washing tower and the quaternary alkali washing tower are connected to the inlet of the cooler through a circulation pump, the outlet of the cooler is connected to the absorption liquid inlet of the alkali washing tower of the same level through a pipeline, the gas inlet of the tertiary alkali washing tower is connected to the gas outlet of the alkali washing tower of the secondary shared circulation tank, the gas outlet of the tertiary alkali washing tower is connected to the gas inlet of the quaternary alkali washing tower, and the gas outlet of the quaternary alkali washing tower is connected to the gas inlet of the vacuum jet unit.

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