1. TSA method chlorine/hydrogen chloride drying

 

1 Overview

 

In the production process of the polysilicon industry, it is necessary to obtain high-purity trichlorosilane by chemical means, and the synthesis of trichlorosilane must use high-purity chlorine, hydrogen and hydrogen chloride gas (water content ≤10-20ppm), so it must be Commercial chlorine (400-1000ppm water) and synthetic hydrogen chloride (1000-3000ppm water) are deeply dried. In the chlor-alkali industry, it is necessary to dry chlorine for chemical production raw materials. Our company provides desiccant and drying process, which can dry the chlorine to below 2ppm. The device runs smoothly and reliably. At present, our company's market share of this type of device is more than 90%.

 

2. Technical indicators

Pressure: Normal pressure～2.0Mpa

Temperature: normal temperature (excluding regeneration)

Water content in chlorine/hydrogen chloride: ≤2～20ppm (adjustable)

Processing gas volume: 50～10000Nm3/h

 

3. The temperature swing adsorption method for drying electronic grade high-purity chlorine/hydrogen chloride has the following advantages

(1) The purification before and after the synthesis of hydrogen chloride all adopts the adsorption method, the production scale is not limited, the process is simple, the degree of automation is high, and the operation is simple.

(2) Significantly reduce power consumption and improve product quality.

(3) Compared with the traditional method, the investment is less, the construction period is shorter, and the area is small.

(4) The equipment used is simple in structure and does not require special materials.

(5) The chlorine/hydrogen chloride loss of the drying device is small, the recovery rate is high, and there is no environmental pollution.

 

 

 

2. TSA method recovers chloride and hydrogen from SiHCl3 or polysilicon tail gas

 

1 Overview

 

In the production of trichlorosilane or polysilicon, a large amount of gas containing various chlorosilanes and hydrogen chloride needs to be discharged. Due to the special properties of chlorosilane and hydrogen chloride, a large amount of money needs to be invested in the treatment of tail gas, which also causes the yield of trichlorosilane to decrease in the production process.

 

The special adsorbent for chlorosilanes developed by our company can recover nearly 100% of chlorosilanes, and at the same time make the recycled hydrogen and chlorosilanes contain no harmful impurities, which fully meets the requirements of polysilicon production.

 

 

 

2. Technical indicators

 

Chloride recovery technical indicators

 

Operating temperature: 0.5～5.0Mpa

 

Operating temperature: normal temperature (adsorption separation process)

 

Processing gas volume: 10～30000Nm3/h

 

Chlorosilane recovery rate: ≥99.99%

 

Hydrogen purity: ≥99.999%

 

Recovery pressure of chlorosilane: Atmospheric pressure

 

Pressure drop of recovered hydrogen: ≤0.05Mpa

 

Carbon content of recovered hydrogen: ≤20ppb (meet the quality requirements of polysilicon reduction furnace for hydrogen)

 

 

3. Advantages of TSA chloride recovery device

(1) The use of special adsorbents has a very high separation coefficient for chlorides and other gases, and can effectively adsorb and separate chlorides with low partial pressure;

(2) The recovered chloride and hydrogen do not contain other harmful substances, which can fully meet the production requirements of polysilicon devices.

(3) Adopting the adsorption method, the process is simple, the energy consumption is low, the degree of automation is high, the operation is simple, and the production scale is not restricted;

(4) The device investment is low, the reduction cycle is short, and the floor space is small.