RTO

Characteristics of Exhaust Gas in Agrochemical & Fine Chemical Production

Exhaust gas from pesticide technical materials, intermediates, and fine agrochemical synthesis is highly specialized and challenging:

1.Complex composition: Contains large amounts of organic solvents such as toluene, xylene, methanol, DMF, dichloromethane, esters, and ethers.

2.Highly toxic components: Includes sulfur-, chlorine-, phosphorus-, and cyanide-containing compounds, as well as amines and heterocyclic pesticide-related odorous substances.

3.Highly fluctuating concentration & intermittent emissions: Emissions vary significantly due to reactor venting and distillation tail gas discharge.

4.High boiling points, prone to coking and polymerization: Easily causes fouling, blockage, and corrosion of equipment.

5.Strong toxicity and persistent odor, difficult to degrade: Conventional treatments such as UV or activated carbon adsorption cannot meet emission standards.

6.Generation of corrosive and toxic gases during incineration: Such as HCl, SO₂, PH₃, and cyanide compounds.

During production processes including feeding, reaction, recovery, centrifugation, filtration, and drying, large amounts of VOCs are emitted.

The agrochemical industry exhaust gas is characterized by complex composition, unstable concentration, and high corrosiveness. When applying RTO treatment, special attention must be given to:

Explosion prevention

Anti-corrosion design

Core Working Principle of RTO for Pesticide Industry

RTO (Regenerative Thermal Oxidizer) operates at 760–900°C to completely oxidize VOCs. The ceramic honeycomb regenerator enables bidirectional heat storage and release, achieving a heat recovery efficiency ≥95%, significantly reducing fuel consumption.

1.Preheating of exhaust gas: Ambient exhaust gas passes through a high-temperature ceramic bed and is rapidly heated to above 750°C

2.High-temperature oxidation: The combustion chamber is maintained at 800–850°C, where VOCs are oxidized into CO₂ and H₂O, with a residence time ≥1.5 seconds

3.Heat recovery: Clean high-temperature flue gas flows through another regenerator, transferring heat to the ceramic media before being discharged at a lower temperature

4.Valve switching: Pneumatic three-way valves switch direction every 90–120 seconds. Three-chamber systems include a purge function to prevent gas bypass, ensuring continuous closed-loop operation

Key Components of RTO for Pesticide Industry

(1) Burner

The burner is the “heart” of the RTO system, determining operational stability.

1.Split-type design

2.Fully automatic load modulation

3.Multi-valve group control for safety and stability

(2) Regenerative Ceramic Media

Unique structure: parallel channel design enhances lateral airflow

Excellent thermal shock resistance: ΔT > 400°C

Strong anti-clogging performance, longer service life

Lower pressure drop, reducing operating costs

(3) Pneumatic Switching Valve

1.External installation for easy maintenance

2.Hard sealing + shaft gas sealing, leakage rate<0.1%

3.Vertical stroke design to prevent sticking during long-term operation

(4) Fan

1.High efficiency, low noise, low vibration, energy-saving

2.Explosion-proof centrifugal design

3.Reliable, high-quality brand suppliers

Technical Parameters of RTO for Pesticide Industry

Airflow Capacity: 50,000 m³/h

Exhaust Source: Exhaust gas from agrochemical intermediate production workshops

Inlet Concentration: NMHC: 3,500–8,000 mg/m³ Main components include toluene, chloromethane, chlorobenzene, methanol, etc. The exhaust gas also contains a certain amount of HCl and various volatile organic compounds (VOCs)

Outlet Emission Standards:

NMHC ≤ 60 mg/m³

Benzene ≤ 4 mg/m³

Dichloromethane ≤ 20 mg/m³

Hydrogen chloride (HCl) ≤ 5 mg/m³

Removal efficiency ≥ 99%

Applicable Agrochemical Exhaust Gas Sources

Vent gas from pesticide synthesis reactors

Non-condensable gases from solvent distillation and recovery systems

Volatile emissions from drying, crystallization, and grinding processes

Odorous exhaust gas from sulfur-, chlorine-, and phosphorus-containing intermediates

Highly toxic, intermittent, and fluctuating organic exhaust gas streams

Advantages of RTO in Agrochemical Industry

Ultra-high destruction efficiency: DRE ≥ 99.9%, effectively decomposing highly toxic and refractory organic compounds

Resistant to catalyst poisoning: Not affected by sulfur, chlorine, or phosphorus compounds, unlike RCO systems

Robust performance: High-temperature resistance, anti-corrosion, and anti-coking design for harsh operating conditions

Excellent energy efficiency: High heat recovery efficiency; medium-concentration exhaust gas can achieve self-sustaining combustion with minimal natural gas consumption

Comprehensive compliance solution: Simultaneously addresses VOC emissions, odor control, and hazardous exhaust gas treatment

Stable continuous operation: Capable of 24/7 operation, fully compatible with continuous agrochemical production processes