Deodorization method

脫臭原理

Scope of application

advantage

shortcoming

1. Masking method

A stronger aromatic odor is mixed with odor to mask the odor and make it acceptable

It is suitable for the occasions that need to eliminate the influence of low concentration odor gas immediately and temporarily. The odor intensity is about 2.5, and there is no organized emission source

The odor effect can be eliminated as soon as possible with high flexibility and low cost

The odor components are not removed

2. Dilution diffusion method

The odorous gas is discharged into the atmosphere through the chimney or diluted with odorless air to reduce the concentration of odorous substances to reduce the odor

It is suitable for the treatment of medium and low concentration of organized odor gas

Low cost
The equipment is simple

It is easy to be restricted by meteorological conditions, and the odor still exists

3. Thermal combustion

Under high temperature, the odor and fuel gas are fully mixed to realize complete combustion

It is suitable for treating combustible gas with high concentration and small volume

The purification efficiency is high, and the odor is completely oxidized and decomposed

The equipment is easy to corrode, consumes fuel, has high treatment cost and is easy to form secondary pollution

4. Catalytic combustion

5. Water absorption method

Some substances in the odor are easily soluble in water, so that the odor components can directly contact with water, thus dissolving in water to achieve the purpose of deodorization

Odor gas from water soluble and organized emission source

The process is simple, the management is convenient, and the equipment operation cost is low

The washing liquid needs to be treated for secondary pollution; the purification efficiency is low, so it should be combined with other technologies, and the treatment effect of mercaptan and fatty acid is poor

6. Liquid absorption method

Some odor components can be removed by the chemical reaction between some substances in the odor and the liquid medicine

It is suitable for the treatment of odor with large gas volume and high and medium concentration

It can deal with some odor components pertinently, and the technology is mature

Low purification efficiency, consumption of absorbent, easy to form and secondary pollution

7. Adsorption method

By using the adsorption function of adsorbent, the odorous substances are transferred from gas phase to solid phase

It is suitable for the treatment of odorous gas with low concentration and high purification requirements

The purification efficiency is very high, and it can deal with multi-component malodorous gas

The adsorbent is expensive and difficult to regenerate, so the odor gas to be treated should have lower temperature and dust content

8. Biological filter deodorization

After the pretreatment process of dust removal and humidification or cooling, the odor gas passes through the filter bed composed of filter materials from bottom to top from the bottom of the filter bed. The odor gas is transferred from the gas phase to the water microorganism mixture phase, and is decomposed by the microbial metabolism fixed on the filter material

At present, biological deodorization method is the most widely studied, the most mature process and the most commonly used method in practice. It can be divided into soil deodorization, composting deodorization and peat deodorization.

Low processing cost

Because of the large area, the fillers need to be replaced regularly, the deodorization process is not easy to control, and problems are easy to occur after running for a period of time, and the treatment of hydrophobic and refractory substances is still difficult.

9. Biotrickling filter

The principle is similar to that of biofilter, but the filter media used are inert materials such as polypropylene balls, ceramics, charcoal, plastic and so on, which can not provide nutrients.

Only the microorganisms which degrade some odorous substances adhere to the filler, and there is no case that the organic matter in the filter media is consumed by the mixed microbial community in the biofilter

The number of microorganisms in the tank is large, which can bear more pollution load than that of biofilter. The inert filter media can not be replaced, resulting in less pressure loss, and the operating conditions are easy to control

It is necessary to add nutrients continuously, and the operation is complex, so its application is limited

10. Washing activated sludge deodorization process

The odor substance is fully contacted with the mixed liquid containing suspended solids, which is removed from the odor in the absorber, and the washing liquid is sent to the reactor to degrade the dissolved odor substance through the metabolic activities of suspended microorganisms

It has a wide range of application

At the same time, the operating conditions are easy to control and the floor area is small

The equipment costs a lot, the operation is complex and needs to add nutrients

11. Aeration activated sludge deodorization process

The malodorous substances were dispersed into the mixed liquid containing activated sludge in the form of aeration, and the odor substances were degraded by suspended microorganisms

At present, it has been used for odor treatment in fecal treatment plant and sewage treatment plant in Japan

After acclimation of activated sludge, the removal rate of malodorous components not exceeding the limit load can reach more than 99.5%.

This method is limited by its application

12. Three phase multi-media catalytic oxidation process

The reactor is filled with special solid composite packing, and the packing is compounded with multi-media catalyst. When the odor gas passes through the packing layer under the action of the induced draft fan, it fully contacts with the liquid-phase compound oxidant sprayed out in the form of divergent mist through the special nozzle on the surface of the solid packing, and under the catalysis of the multi-media catalyst, the pollution factors in the odor gas are fully decomposed.

It has a wide range of application, especially for the treatment of large gas volume, medium and high concentration waste gas, and has a good removal rate of hydrophobic pollutants.

It has the advantages of small land occupation, low investment, low operation cost, convenient management, instant use, impact load resistance, and not easy to be affected by pollutant concentration and temperature changes.

A certain amount of medicine should be consumed

13. Low temperature plasma technology

In the process of dielectric barrier discharge (DBD), particles with high chemical activity, such as electrons, ions, free radicals and excited molecules, are produced in the plasma. The pollutants in the waste gas react with these active groups with high energy, and finally convert into CO2 and H2O, so as to achieve the purpose of purifying waste gas.

It has wide application range and high purification efficiency, especially suitable for multi-component malodorous gas which is difficult to be treated by other methods, such as chemical industry, medicine industry, etc.

It has the advantages of high electron energy, can interact with almost all odorous gas molecules, low operating cost, fast reaction, quick start and stop of the equipment, and can be opened as soon as it is used.

High one-time investment