KR19980052152A - Polysulfide reaction accelerator and method for the coke oven gas purifier - Google Patents

Abstract

The present invention is to produce free sulfur (Na ₂ Sxt1) of free sulfur liberated from hydrogen sulfide (H ₂ S) which is a harmful component in the coke oven gas in a deoiler for purifying the gas generated during coke distillation. The present invention relates to a method and a device for activating the present invention, and a method and a device for activating polysulfide production for converting sodium cyanide (NaCN) into rodan salt (NaSCN).

In the configuration, in the coke oven gas purification apparatus configured to be connected to the absorption tower 10 and the regeneration tower 20, the buffer tank 30 and the dissolution tank 40 to be sequentially reacted;

Sodium hydroxide inlet 50, a mixer 60 for mixing sodium hydroxide and free sulfur, and a free sulfur dissolving agent for heating and dissolving free sulfur on the low sulfur passage that is moved from the regeneration tower 2 to the buffer tank 30. (70), the melting tin (40) and the liquid temperature raising device (31) (41) formed inside the buffer tank 30, completely dissolving free sulfur and supplying to the buffer tank (30) harmless to the poisonous sodium cyanide Prevents corrosion in the device by NaCN by making sufficient polyemulsion reaction (Na2Sx + S → Na2Sxn) to transform into rotan salt, and decreases gas absorption efficiency caused by free sulfur unresolved, and release of NaCN The present invention relates to a polysulfate reaction promoting device in a coke oven gas purification device which prevents water pollution caused by water.

Description

Polysulfide reaction accelerator and method for the coke oven gas purifier

The present invention relates to a polysulfate reaction accelerator and method thereof in a coke oven gas purifier;

Activates the generation of free sulfur to polysulfide (Na ₂ Sxt1) free from hydrogen sulfide (H ₂ S), a toxic component in coke oven gas, in a deoiler that purifies the gas generated from coke distillation. TECHNICAL FIELD The present invention relates to an apparatus and a method for activating polysulfide production for converting sodium cyanide (NaCN) absorbed into a coke absorption liquid into harmless rhodan salt (NaSCN).

In general, in order to use the coke oven gas for other purposes, it is necessary to properly purify the harmful components (H ₂ S, HCN) in the gas.

The reason is that when the gas is used in the furnace of the steelmaking process, the steel is vulnerable, and when released into the atmosphere, it causes pollution and harms the human body.

Therefore, the method of removing the harmful components is used and the conventional purification method is H ₂ S and HCN contained in the coke oven gas sent to the absorption tower 10 as shown in Figure 1 is provided in the absorption tower (10) Reacted with sodium hydroxide (NaOH) (H2S + NaOH → NaHS + H ₂ O) (HCN + NaOH → NaCN + H ₂ O) H ₂ S and HCN, which are harmful ingredients, are absorbed by NaHS and NaCN The coke oven gas that remains in the tower and is purified is used as a cold-rolling plant heat source through the absorption tower 10 upper outlet 12.

The filthy liquid, which is an absorbent liquid absorbing harmful components in the gas, is collected at the bottom of the absorption tower 10 and is transferred to the regeneration tower 20 by a pump, and the regeneration tower blows air and reacts with oxygen contained in the air to reproduce and regenerate oxidation. Reaction (NaHS + 1 / 2O2 → NaOH + S ↑) is carried out at this time free liberated sulfur is sent to the buffer tank (30) to the polycracking reaction to harm the sodium cyanide (NaCN) in filth Na ₂ Sx + S → Na ₂ Sxt1) is reacted with sodium cyanide and the product produced by the polymulsification reaction (Na2Sxt1 + NaCN → NaSCN + Na ₂ Sx) to make the poisonous sodium cyanide (NacN) harmless It converts to salt (NaSCN) and uses a method of purifying (H ₂ S, HCN), which is a harmful component in gas.

However, in the conventional apparatus, the free sulfur (S ↑) liberated during oxidation and regeneration in a regeneration tower is a polymulsification reaction (Na ₂ Sx + S → Na ₂ ), which is a preparatory step for detoxifying highly toxic sodium cyanide (NaCN). Sodium cyanide (NaCN) when the highly toxic sodium cyanide (NaCN) is discharged to the outside of the device without reacting with rhodium salt (NaSCN) because it is present in the bottom of the buffer tank 30 without forming Sxt1). There is a problem of water pollution caused by the problem to increase the wastewater treatment costs to prevent this.

In addition, the free sulfur in the undissolved state becomes a bubble, causing a foaming phenomenon to flow over the regeneration tower 20 and the buffer tank 30, the gas purification efficiency is lowered, and the sodium cyanide remaining in the device is the piping of the device And the problem of reducing the life of the device by corroding the device.

Therefore, the technical problem to be achieved by the present invention is an apparatus and method for converting the highly toxic sodium cyanide to harmless rodan salt by forming a high-efficiency polysulfide production reaction by dissolving free sulfur sufficiently in a deoiler to solve the above problems. To provide.

1 is a configuration diagram of a conventional coke oven gas purification device

2 is a configuration diagram of a coke oven gas purification apparatus provided with the present invention

FIG. 3 is a detail A diagram of FIG. 2.

* Description of the codes on the main parts of the drawings *

10 absorption tower 11: gas inlet pipe

12: gas discharge pipe

20: regeneration tower

30: buffer tank 31: steam pipe

40: melting tank 41: steam pipe

50: sodium hydroxide inlet

60: mixer 61: mixing wings

70: dissolver 71: tube

72: steam inlet 73: steam outlet

74: cell

Method for achieving the technical problem to be achieved by the invention;

In the coke oven gas purification apparatus is connected to the absorption tower and regeneration tower, the buffer tank and the dissolution tank to perform the reaction sequentially;

(H ₂ S + NaOH → NaHW + H ₂ O) (HCN + NaOH → NaCN + H ₂ O) produced by the reaction of absorption tower, NaHS in NaHS and NaCN is redox reaction (NaHS + 1 / 2O) ₂ → NaOH + S ↑) to generate free sulfur.

Therefore, sodium hydroxide is introduced into the passage between the absorption tower and the buffer tank, and sodium hydroxide and free sulfur are mixed to remove free sulfur as a means to solve the problems caused by undissolved sulfur. The polysulfide (Na2Sxn) produced by the polyemulsification reaction (Na ₂ Sx + S → Na ₂ Sxt1) with the dissolved free sulfur by heating the solution of the buffer tank and the dissolution tank with sodium cyanide (NaCN) This step consists in promoting the reaction (Na2Sxn + NaCN-> Na ₂ Sx).

In addition, the configuration of the present invention will be described;

It is installed on the passage of free sulfur moving from the regeneration tower to the buffer tank and is equipped with a sodium hydroxide inlet and a mixer equipped with a mixing wing for mixing sodium hydroxide and free sulfur. Passing through the outside, the other side is composed of a free sulfur dissolver connected to the buffer tank, a steam pipe formed inside the dissolution tank and the buffer tank.

Hereinafter, described in detail with reference to the accompanying drawings.

Mixing blades 61 which are combined in the rear end of the sodium hydroxide inlet 50 formed on the pipe which is a passage of free sulfur moved from the regeneration tower 20 to the buffer tank 30 and mixed with free sulfur. Mixer 60 is provided;

One side of the mixer 60 and the flange are coupled to each other, and the steam inlet 72 and the outlet 73 through which steam passes therein are spaced apart from the outer circumferential surface of the cell 74 and pass through a predetermined distance. Steam is flowed into the free sulfur dissolver 70 and the dissolution tank 40 and the buffer tank 30 provided with the dissolver tube 71 coupled to the pipe connected to the buffer tank 30 while the other side conducts heat. It consists of the steam pipe 41 so that.

Hereinafter will be described with respect to the operation.

The soil solution absorbing H ₂ S and HCN harmful substances in the coke oven gas in the absorption tower 10 is transferred to the regeneration tower 20 by a pump, and the soil solution is regenerated by the oxidation and regeneration reaction by air and absorbed into the absorption liquid. Free sulfur sprinkled from the top of the tower 10 and separated from the filth solution is supplied with 45% NaOH solution introduced from the sodium hydroxide inlet 50 provided on the regeneration tower 10 and the buffer passageway, and is coupled to the rear end of the inlet by Hurenji. The free sulfur, which is sent to the mixer 60 and sufficiently mixed by the mixing blade 61 provided therein, increases the alkalinity and the alkalinity is increased, is transferred to the dissolver tube 71 to the steam introduced into the cell 74. Dissolution is achieved by conduction heat.

Dissolved free sulfur is sent to the buffer tank 30 to achieve a sufficient polymulsification reaction (Na ₂ Sx + S → Na ₂ Sxn).

In addition, sodium cyanide (NaCN) in the filthy fluid absorbed by harmful components in the gas in the absorption tower 10 is supplied to the dissolution tank 40 to steam the liquid temperature riser provided in the buffer tank 30 and the dissolution tank 40 The chemical reaction temperature is increased by the pipe 41 to react with the polysulfide (Na ₂ Sxn) produced by the polyemulsion reaction, that is, the poisonous sodium cyanide (NaCN) detoxification reaction (NaCN + Na ₂ Sxn → NaSCN + Na). ₂ Sx) is promoted to transform the highly toxic sodium cyanide into rhodan salt.

The free sulfur separated from the regeneration tower was completely dissolved in the dissolver and supplied to the buffer tank, so that the polycyclic reaction (Na ₂ Sx + S → Na ₂ Sxn) to convert the highly toxic sodium cyanide to harmless rodan salt was sufficiently performed. Corrosion in the device by NaCN is prevented;

The complete dissolution of free sulfur prevents the decrease in gas absorption efficiency caused by the foaming phenomenon due to the accumulation of unsolved phases, and by removing and discharging NaCN completely, there is an effect of reducing the wastewater treatment cost and water pollution for removing NaCN.

Claims (2)

NaHS in NaCN and NaCN by (H ₂ S + NaOH → NaHS + H ₂ O) (HCN + NaOH → NaCN + H ₂ O) reaction in absorption tower (10) + 1 / 2O ₂ → NaOH + S ↑) absorption tower 10 and the regeneration tower 20 is generated free sulfur, In the coke oven gas purification device configured to be sequentially connected to the buffer tank 30 and the dissolution tank 40, the hydroxide on the free sulfur passage that is moved to the buffer tank 30 to the absorption tower (10) Coke oven gas purification comprising the steps of adding sodium, mixing sodium hydroxide and free sulfur, dissolving free sulfur by heating, and heating the liquid in the buffer tank 30 and the dissolution tank 40. Method for promoting polysulfide reaction in apparatus. In the coke oven gas purification apparatus configured to be sequentially connected to the absorption tower 10 and the regeneration tower 20, the buffer tank 30 and the dissolution tank 40, the reaction is performed, Sodium hydroxide inlet 50 is provided on the free sulfur passage from the regeneration tower 20 to the buffer tank 30, the mixer 60 is provided with a mixing blade 61 for mixing sodium hydroxide and free sulfur, One side is coupled to the rear end of the mixer 60 and the inside passes through the outside of the cell 74 coupled with the steam pipe and the other side is a free sulfur dissolver 70 connected to the buffer tank 30, A multi-sulfide reaction promoting device in the coke oven gas purifier, characterized in that consisting of the dissolution tank 40 and the steam pipe 31, 41 formed in the buffer tank (30).