1: Silicide

2: Sulfide

3: Others

4. Degree of damage

Usually, silicide is regarded as a toxic substance of catalytic combustion sensor, that is, it completely destroys the catalyst. Sulfide, etc. are regarded as inhibitory substances, that is, only the sensitivity of measurement is reduced. This inhibition or reduction may be long-term and irreversible, or it may be temporary and recoverable.

1. Choose catalytic elements with strong antitoxic ability. It is proved that new catalysts such as composite metal oxide catalysts prepared by chemical coprecipitation can enhance the stability of the surface of catalytic elements. Improve the anti-poison ability of components. The new catalyst is also used, but the toxicity of products from different manufacturers may be quite different. Choosing better quality catalytic elements can effectively improve the average trouble-free working time of combustible gas detectors.

2. In the environment where there are substances that can cause poisoning of catalytic combustion sensors, a filter should be installed at the inlet of the suction pump of the instrument or in front of the sensor room. According to the pollution situation on site, it should be replaced frequently, or immediately after being exposed to toxic gas.

3. Avoid contacting the sensor with silicide and sulfide. If gaskets, sealing and insulating components containing silicone rubber, synthetic rubber or sealant are not used, polishing agents, cleaning agents and lubricants containing silicide should not be used in the environment where instruments are assembled and stored, and lubricants containing silicide should be avoided in parts such as valves of gas transmission network, and labels that can be self-adhered on the surface of instruments should not be used as far as possible (such adhesives often contain silicide); Installation and maintenance personnel should not use cosmetics containing silicone oil.

4. According to the actual situation, the concentration of the possible leaked gas should be estimated, and the combustible gas detector with appropriate range should be selected to avoid making the sensor work in the environment with high concentration of leaked gas for a long time.