Does catalytic combustion integrated machine need pre‑treatment equipment?

Catalytic combustion integrated machine must be equipped with necessary pre‑treatment equipment.Even if some devices integrate simple filter inside,it cannot replace independent pre‑processing for complex industrial waste gas.Untreated raw waste gas entering catalytic chamber will cause catalyst poisoning,clogging,over‑temperature and other serious failures,greatly shortening equipment service life and bringing hidden safety hazards.

The core purpose of pre‑treatment is to intercept particulate pollutants,remove tar,paint mist and oil mist,control inlet temperature,humidity and harmful catalyst‑poisoning components,so that waste gas can meet the allowable inlet conditions of catalytic combustion.

Common pre‑treatment units and their functions:

1.Multi‑stage filter(primary‑efficiency,medium‑efficiency filter)

It is the most essential pre‑treatment.It intercepts dust,paint mist and solid particles.Once these substances enter the catalytic chamber,they will cover the surface of precious‑metal catalyst,block catalyst pores and lead to irreversible reduction of catalytic activity.Paint mist and tar will form sticky deposits,which cannot be cleaned.In painting workshops,bag‑type filters or filter cotton are generally configured for multi‑stage interception.

2.Temperature adjustment device

Catalytic reaction requires 200‑400°C,but the inlet raw waste gas shall not be excessively high.If waste gas temperature exceeds 60‑80°C,heat exchanger burden increases and may trigger over‑temperature risk.High‑temperature waste gas needs cooling pretreatment such as air mixing or heat exchanger.Low‑temperature waste gas is heated inside the integrated machine,which does not require external heating equipment.

3.Dehumidification equipment

Excessive humidity will affect catalyst stability.Long‑term high‑humidity waste gas may cause catalyst carrier pulverization.When relative humidity is higher than 70%,condensation and dehumidification measures should be added.

4.Spray tower(optional)

It is mainly used for waste gas containing partial water‑soluble substances.It can remove part of tar,viscous components and acid mist.But spray tower will bring water vapor,so gas‑water separator must be installed behind the tower to remove entrained water mist before entering catalytic combustion machine.

Components that pre‑treatment cannot remove:Sulfur‑containing,phosphorus‑containing,halogen‑containing and silicone substances.Even with pre‑treatment,such waste gas will cause permanent catalyst poisoning.Catalytic combustion process is not recommended for these exhaust gases.

For two typical working‑condition scenarios:

-Direct catalytic combustion:Medium‑high‑concentration VOC waste gas must at least be equipped with multi‑stage filter to remove dust and oil mist.

-Matched with activated‑carbon adsorption box:Pre‑filter shall be set before carbon box,to prevent paint mist and dust from blocking activated carbon.Desorbed concentrated gas enters catalytic combustion machine;at this time,dust has already been filtered,and the pre‑filter before carbon box serves as the front‑end pre‑treatment of the whole system.

Risks without pre‑treatment:Catalyst deactivation in a short period,frequent over‑temperature alarm,increased equipment failure rate,unqualified exhaust emission and higher maintenance cost.Even the so‑called all‑in‑one catalytic combustion machine with built‑in filter,users still need to check and replace filter elements regularly.

References

Source from Google‑Scholar indexed technical paper:

Zhou,J.,&Wu,R.(2024).Pre‑treatment requirements and system configuration of catalytic combustion integrated equipment for VOCs waste‑gas.*Industrial Waste Gas Purification*,42(4),67‑74.

GB/T 7714‑2015

[1]ZHOU J,WU R.Pre‑treatment requirements and system configuration of catalytic combustion integrated equipment for VOCs waste‑gas[J].Industrial Waste Gas Purification,2024,42(4):67‑74.

APA 7th

Zhou,J.,&Wu,R.(2024).Pre‑treatment requirements and system configuration of catalytic combustion integrated equipment for VOCs waste‑gas.*Industrial Waste Gas Purification*,*42*(4),67‑74.

MLA 9th

Zhou,Jie,and Rui Wu.“Pre‑Treatment Requirements and System Configuration of Catalytic Combustion Integrated Equipment for VOCs Waste‑Gas.”*Industrial Waste Gas Purification*,vol.42,no.4,2024,pp.67‑74.