JPS6129613A - Method of burning and deodorizing waste gas - Google Patents

Abstract

PURPOSE:To remove gas tar material and eliminate an explosion potential by a method wherein waste gas is injected onto the waste gas between the facility for generating waste gas and a combustion and deodorizing furnace. CONSTITUTION:Waste gas is guided into the lower part of a cylindrical water injection device 1 and in a direction of tangential line under an operation of a discharging fan 9, and discharged from the top end of the water injection device 1 while being lifted along the inner wall of the cylinder in a spiral form. The waste gas is contacted with water injected from the injection nozzle 2 arranged at the top end of the water injection device 1 while being guided in a spiral form, thereby gas-like tar contained in the waste gas becomes a liquid tar 3 and settled at the bottom part 4 of a circulating tank 4. With this arrangement, the gas-like tar in the waste gas is removed and thus it is possible to remove an explosive potential such as a source of ignition and film detonation.

Description

[Detailed Description of the Invention] [Industrial Application Field] The invention relates to a method for combustion deodorization of `f6 combustible waste gas generated from resin manufacturing processes, resin processing processes, etc.0 [Prior Art] Combustible Recently, the cylinder combustion power method, which has the highest processing efficiency of 1%, has been adopted for the removal of sex gases.

This combustion method involves the risk of explosion since the target to be treated is flammable gas, so various safety measures are taken.

One of the safety measures is to prevent flames from the combustion furnace from backfiring and causing fires in the ducts and manufacturing equipment. To prevent this, one method is to install a flashback prevention device in the duct that connects the combustion furnace and manufacturing equipment.

Conventionally, fire extinguishing agent (Halon 13
A fire extinguishing system 7 is equipped with a light source (such as 01) installed, and when the flame backfires and the flame propagates, it is detected by the deviation or pressure at this time, and if the temperature exceeds a certain set temperature or pressure, the fire extinguishing system will explode. Fire extinguishing agent was then sprayed, and a sword was used to prevent the spread of the flames. However, with this method, there is a possibility that the flame propagation cannot be stopped in the case of extremely fast flame propagation (Matsuha 5-6) such as detonation, even if the extinguishing agent is sprayed after detecting the temperature or pressure. be.

[Purpose of the invention]

This is to avoid the possibility that conventional flame propagation cannot be prevented.

1) If the waste gas contains gaseous resin (commonly referred to as tar), this tar will adhere to the inside of the duct and solidify when cooled, causing the duct to become clogged. l (Since this tar is an insulator, it becomes electrically charged and becomes an ignition source (discharge ignition due to static electricity), which also becomes a combustion source and has explosive potential.0 Tar accumulates in this pipe and comes into contact with an ignition source. The phenomenon of tetonation, which causes combustion and detonation, has recently been studied, and several cases of explosion accidents caused by the accumulation of combustibles (lubricating oil) have been reported. It also removes tar.

[Structure of the invention]

Waste gas generation equipment that uninventively generates waste gas containing flammable gas
In a method for deodorizing combustion gas by supplying it to a combustion deodorizing furnace, the waste gas is injected with water grapes between the waste gas generation equipment and the combustion deodorizing furnace. 〇 Figure 1 shows the 20-sheet τ of the coating machine waste gas combustion deodorization treatment that uses only water for circulation and injection, and includes the water injection device τ 〇 Figure 2 U' [If Alkilolua C inside
H2GHz OH1 Mid° type surfactant (R-CON〈H2of(2oH
7. When the water is injected and water is injected, the coating machine waste gas combustion deodorizing treatment is shown in 20 sheets.・
In order to remove vine vapor-like tar that becomes a source of detonation and ignition, combustible gas generated from coating machines etc. The tar is injected and settled in a circulation tank 4 as #-shaped tar 6, and the settled tar is discharged out of the system by a car pump 5 or the like. Water injection is carried out by a circulation pump 6, and a ball tap device 7 for water supply is installed so that the water is carried away by the outlet gas of the water injection device 1. It is released into the outlet gas of this water injection device and is not included in the vaporized tar. In addition, injecting an alkylolamide type surfactant 'f into the piping between the circulation pump 5 and the syringe 2 at the 1ζ stage (lowering the V5 degree τ of the tar) to make it easier to take out the rL autumn tar 3. Effective. Further, it is preferable that the water injection device applies salt 9 to two locations, one at the spray gas outlet of the coating machine and the other gas inlet of the deodorizing furnace.

For the purpose of preventing flame propagation, it is preferable that the amount of circulating water to be injected and the liquid/gas ratio (mole ratio) of waste gas be 7 or more, and the injection method is to arrange the injection nozzles in several rows or rows as shown in Figure 6. It is best to overlap the V mounting and injection areas.

When it backfires, burns, and detonates, a sudden burst of pressure is generated along with the flame. For this reason, there is a high possibility that simple spraying will be blown away by this pressure.

Therefore, when spraying, the pressure must be dissipated through the pressure dissipation port.

Preface to the fourth side δ (No changes to the content) If high-pressure injection is used, it will not be blown away even at the above pressure, and flames can be prevented. However, it is necessary to eliminate gaps in the injection zone. If this gap is eliminated, the flame will become discontinuous, and flame propagation will definitely be eliminated.

An embodiment of the folding gas combustion deodorizing process flow sheet shown in FIG. 1, which includes a water injection device that injects and circulates only water and a circulation tank, will be described.

[Example 1] Table 1 Components and concentration of waste gas *: Gaseous tar concentration unit is rrIg/kg.

Waste gas having the components and concentrations shown in Table 1 is discharged from the coating machine at a gas flow rate of 300 Nrn'/1 nin and a temperature of 120°C. The waste gas is introduced into the lower part of the cylindrical water injection device 1 and the kissing direction of the cylinder by the exhaust hole 9, and as it rises spirally on the inner wall of the cylinder, the top force of the water injection device 1 is increased.
It is discharged in the direction of tangential force. During the spiral upward movement of the waste gas, the gaseous tar contained in the waste gas comes into contact with water injected from the spray nozzle 271' provided at the top of the injection device 1 at 7. Liquid tar 6 and 'z!
It settles to the bottom of the 11 circulation. The water injected from the two injection nozzles 1 is separated from the tar 6 in a circulation tank 4, and is supplied by a pump 6.

Gas air volume 300 Nm7m1n, circulating water volume t1,
2 m'/min (Circulating water amount 1.2 m'/min
= 67 kg-mol/min gas with a quantity of 300 N
If m7m1n = 13.4kg mo I/min, liquid/gas ratio 5 (see Table 2), the outlet tar concentration σs,
(S mg/kg and l-lactal removal rate are 280-5
．． 6/2.80X100298%. Injection pressure is 5
kg/an'.

The amount of circulating water is calculated and π and @ (Europe/Gas ratio is specified)
Table 2 shows the tar removal rate and outlet tar concentration of t'fI (no change in content).

Table 2 Liquid/Gas Ratio (Molar Ratio), Tar Removal Rate, and Outlet Tar Concentration The temperature of the circulating water was 64°C, and the temperature of the gas discharged from the top of the water injection device 1 was 37°C. Coating machine 8 and water injection device 1
The duct connecting the two is heated 16 with hot air.

The waste gas that comes into contact with the water injected from the injection nozzle 2 carries water with it, so that the amount of water in the circulation tank 4 decreases.

For this reason, the circulation tank 4 is equipped with a water tag device 7 for automatic water supply.

The amount of waste gas was 600 Nm7mln, and the amount of acid water received in the circulation tank 4 was 23m'/day.

In addition, the circulation tank 4 is divided into 2 parts to separate 6 basins of liquid tar, and the liquid tar settled in the tank is discharged to the outside by a gear pump 5 with 6 tanks, and the supernatant liquid is transferred to the tank of other power. It overflows into the air and is sent to the spray nozzle 2 by the circulation pump 6.

Add liquid tar 3 to 4 at a water temperature of 37°C. QQQ~5゜000
CPL/) Because of its viscosity, it is very difficult to discharge.

For this reason, an alkylolamide type surfactant (RCON < CHzCHzOH), injection CH
2CH20H Then, the enemy tar will soften and be discharged easily (Mouse 2
figure).

The tar removal rate in the waste gas is 280111g/kgK vs. the surfactant concentration in the shite circulating water is approximately 60 [11g/kg (
#) Then, the tar viscosity is 2゜5.
Q Decrease in OCP.

Furthermore, when the surfactant concentration was increased, the tar viscosity decreased to below 1.0 OOCP.

Since water droplets are entrained in the outlet gas that has passed through the injector, they are removed by the eliminator 18.

The water droplets are returned to the circulation tank 4. The wet waste gas that has passed through the eliminator is sent to the heat exchanger at the outlet of the combustion furnace 1Q by the air supply unit 19.The temperature of this wet waste gas is raised to 400°C by the heat exchanger, and then it is combusted. sent to the furnace,
When it comes into contact with the flames, it is decomposed. At the time of burning, the combustion temperature was 800°C. Is this Tsutsubuchi combustion gas the aforementioned heat source? A
The waste heat is guided to the vessel 11, the waste heat recovery device 12, and then to the chimney. The amount of steam recovered in the waste P recovery device 12 was 1.7 t/hr, and the temperature of the gas exhausted to the chimney was 200°C.

〔Effect of the invention〕

According to the invention, 1. Even if there is combustion or explosion due to backfire from the waste gas generation equipment or waste gas combustion furnace, the water jet film from the water jet nozzle will cause the combustion and 2. By contacting with water jetted from the water injection nozzle, more than 98% of the gaseous tar in the waste gas is removed, and explosive potential such as ignition sources and film tetonation can be eliminated.

[Brief explanation of drawings]

1 and 2 are 20-sheet illustrations of the inventive combustion deodorizing process. FIG. 6 is a plan view of the water injection device. Explanation of symbols 1 Water injection device 2 Injection nozzle 6 Liquid tar 4 Circulation tank 5 Gear pump 6 Circulation pump 7 Ball tap device 8 Coating machine 9 Exhaust fan 10
Combustion furnace 11 Heat exchanger 12 Separate recovery device 15 Surfactant tank 16 P-air heating section 21 Waste gas outlet procedure amendment (method)

Claims (1)

[Scope of Claims] 1. In a method of supplying waste gas containing flammable gas from waste gas generation equipment to a combustion deodorizing furnace to perform combustion deodorization, water is added to the waste gas between the waste gas generation equipment and the combustion deodorization furnace. A method for combustion deodorization of waste gas, characterized in that it is injected. 2. A combustion deodorizing method for waste gas according to claim 1, which comprises injecting water containing an alkylolamide type surfactant.