Regenerative Catalytic Oxidizer (RCO Series)

Product Overview

The RCO series regenerative catalytic oxidizer is specially designed for treating medium- to high-concentration industrial organic exhaust gas, typically within a VOC concentration range of approximately 1,000–10,000 mg/m³.

The system can also be integrated into an activated carbon adsorption concentration and catalytic combustion process, where it replaces the conventional catalytic combustion chamber and heating unit.

RCO technology is particularly suitable for applications requiring a high heat recovery rate. It is also well suited to production lines where the exhaust gas composition changes frequently due to different products or where VOC concentrations fluctuate significantly.

The system can treat a wide range of organic compounds, including aromatic hydrocarbons, ketones, esters, phenols, aldehydes, alcohols, ethers and other hydrocarbon-based pollutants.

During treatment, the organic exhaust gas is heated to approximately 280°C or above. Under the action of the catalyst, VOCs are oxidized and decomposed into carbon dioxide and water vapor.

The medium- to high-temperature gas generated during catalytic oxidation passes through the heat recovery section and transfers most of its thermal energy to the incoming exhaust gas. This reduces the fuel required to raise the inlet gas temperature and improves overall operating efficiency.

Working Principle

Organic exhaust gas is drawn into the oxidation system by a centrifugal fan. The gas is heated by the burner or auxiliary heating system until it reaches an operating temperature of approximately 250–300°C.

At this temperature, the organic compounds in the exhaust gas pass through the catalyst bed and are oxidized into carbon dioxide and water.

The high-temperature treated gas then enters a specially designed ceramic heat-storage chamber. More than 95% of the thermal energy can be absorbed and stored by the ceramic media under suitable operating conditions.

After transferring its heat to the ceramic media, the treated gas temperature drops to a level close to the inlet gas temperature and is discharged through the exhaust stack.

A regenerative catalytic oxidation system normally consists of two or three heat-storage chambers. Under PLC control, the gas flow direction is switched periodically so that the system continuously completes preheating, catalytic oxidation, heat storage and purging.

First, untreated exhaust gas enters a previously heated heat-storage chamber. The ceramic media transfers stored heat to the incoming gas, raising its temperature before it enters the catalytic oxidation chamber.

After oxidation, the purified high-temperature gas passes through another heat-storage chamber, where it releases thermal energy to the ceramic media before being discharged.

In a three-chamber system, a portion of the purified gas is directed into the third chamber to purge any residual untreated exhaust gas. This helps prevent untreated gas from being discharged during valve switching.

For applications with less stringent pollutant removal requirements, a two-chamber configuration may be selected to reduce equipment investment.

Operating Process

Process Stage	Description
1. Exhaust Gas Collection	Organic exhaust gas is collected and transported to the RCO system through the duct network.
2. Gas Preheating	The incoming gas passes through a heated ceramic heat-storage chamber and absorbs stored thermal energy.
3. Auxiliary Heating	When necessary, the burner or electric heating system raises the gas to the required catalytic oxidation temperature.
4. Catalytic Oxidation	VOCs pass through the catalyst bed and are oxidized into carbon dioxide and water vapor at a relatively low temperature.
5. Heat Recovery	The treated hot gas transfers its heat to another ceramic heat-storage chamber.
6. Purging	In a three-chamber system, purified gas is used to purge residual untreated gas from the standby chamber.
7. Automatic Flow Switching	PLC-controlled valves periodically reverse the airflow direction to maintain continuous heat recovery and treatment.
8. Compliant Discharge	Purified gas is discharged through the exhaust stack after meeting the required emission standard.

Key Features

• High gas hourly space velocity, typically above 30,000 h^-1
• VOC purification efficiency can exceed 99% under suitable operating conditions
• High operating safety and stable treatment performance
• Low-temperature catalytic oxidation reduces fuel consumption
• High-efficiency regenerative heat exchange improves economic performance
• Heat recovery efficiency can reach 95% or higher
• Compact equipment structure with a relatively small footprint
• Optional waste heat recovery for production heating or drying lines
• Low operating cost when VOC concentration is sufficient to support self-sustaining operation
• No significant thermal NOx generation under normal catalytic oxidation conditions
• Fully automatic PLC control with convenient operation and management
• Suitable for exhaust gas with fluctuating concentration and composition
• Two-chamber or three-chamber configurations available

Technical Advantages

Item	Typical Description
Suitable VOC Concentration	Approximately 1,000–10,000 mg/m³
Catalytic Operating Temperature	Approximately 250–500°C, depending on the catalyst and VOC composition
Typical Treatment Temperature	Approximately 250–300°C
VOC Removal Efficiency	Up to 99% or higher under suitable design conditions
Heat Recovery Efficiency	≥95%
Gas Hourly Space Velocity	>30,000 h-1
Heat Storage Media	High-efficiency ceramic heat-storage material
Catalyst Type	Precious-metal or transition-metal catalyst supported on saddle-shaped or honeycomb ceramic media
Control Method	PLC automatic control with system interlocks
Available Configuration	Two-chamber or three-chamber regenerative structure

System Components

Component	Function
Combustion and Heating Unit	Provides auxiliary heat during system startup and low-concentration operating conditions.
Regenerative Chambers	Contain ceramic heat-storage media for gas preheating and thermal energy recovery.
Catalyst Bed	Promotes VOC oxidation at a lower temperature than direct thermal combustion.
Flow Reversing System	Uses automatic valves to switch gas flow between the heat-storage chambers.
Purging System	Removes residual untreated gas from the standby chamber before switching.
Exhaust System	Discharges purified gas through the fan and exhaust stack.
PLC Control Cabinet	Controls temperature, valve switching, fan operation, alarms and safety interlocks.
Connecting Ductwork	Connects exhaust gas collection, oxidation, heat recovery and discharge sections.

Regardless of the selected system configuration, regenerative chambers containing the heat-storage media must normally be arranged in pairs or as part of a coordinated multi-chamber system.

Catalytic Oxidation Technology

The RCO system uses a dedicated catalyst supported on saddle-shaped or honeycomb ceramic media. The catalyst may contain precious metals or transition metals selected according to the pollutant composition and operating requirements.

Because the catalyst lowers the activation energy required for VOC oxidation, organic pollutants can be decomposed at approximately 250–500°C instead of the much higher temperatures required for direct thermal oxidation.

This reduces fuel consumption, decreases equipment thermal load and helps lower the overall investment and operating costs.

Waste Heat Recovery

The high-temperature gas produced after catalytic oxidation contains recoverable thermal energy. In addition to regenerative heat recovery inside the RCO system, optional heat exchangers can be installed to supply hot air or hot water to other production processes.

Recovered heat can be reused in drying ovens, coating lines, production heating systems or other processes requiring thermal energy.

For facilities with drying lines, recovering the oxidation heat can significantly reduce overall energy consumption.

Applicable Industries

• Automotive coating production lines
• Shipbuilding and marine coating operations
• Motorcycle and bicycle manufacturing
• Household appliance production
• Container coating and drying lines
• Petroleum and petrochemical industries
• Chemical manufacturing
• Rubber product production
• Paint and coating manufacturing
• Shoe adhesive and bonding processes
• Plastic product manufacturing
• Metal printing and can manufacturing
• Printing ink production and printing lines
• Cable and enameled wire production
• Industrial drying lines requiring heat recovery

Typical Treatable Organic Compounds

Compound Category	Typical Examples
Aromatic Hydrocarbons	Benzene, toluene, xylene and related aromatic compounds
Ketones	Acetone, methyl ethyl ketone and other ketone compounds
Esters	Ethyl acetate, butyl acetate and other ester solvents
Phenols	Phenol and related phenolic compounds
Aldehydes	Formaldehyde and other aldehyde compounds
Alcohols	Ethanol, methanol, isopropanol and other alcohol vapors
Ethers	Ether-based organic solvents
Hydrocarbons	Mixed hydrocarbon vapors and petroleum-based VOCs

Operating Cost Advantages

When the organic exhaust gas concentration reaches a sufficient level, typically around 1,000 mg/m³ or higher depending on its calorific value, the oxidation heat released by the VOCs can help maintain the required operating temperature.

Under suitable conditions, the auxiliary heating system may operate intermittently or stop after startup, significantly reducing fuel consumption.

The actual self-sustaining concentration depends on VOC composition, airflow, heating value, moisture content, heat recovery efficiency and system heat loss.

Safety and Automatic Control

• Automatic temperature control
• High-temperature alarm and shutdown protection
• Fan and valve interlock control
• Combustion flame monitoring
• Overpressure and abnormal pressure alarm
• PLC-controlled chamber switching
• Automatic purging before startup and flow switching
• Emergency shutdown protection
• Optional VOC concentration and LEL monitoring

Important Operating Requirements

Before selecting and operating the RCO system, the exhaust gas composition and installation environment must be carefully evaluated.

Unsuitable or Restricted Substances

• Highly viscous oil or ester-like substances that may coat the catalyst surface
• Phosphorus-containing compounds
• Arsenic-containing compounds
• Antimony compounds
• Mercury compounds
• Lead compounds
• Zinc compounds
• Tin compounds
• High concentrations of dust or particulate matter

These substances may poison, block or damage the catalyst and must be removed through appropriate pretreatment before the gas enters the RCO system.

Installation Environment

• The installation area should be free from highly corrosive gases.
• Outdoor equipment should be provided with effective rain protection.
• Adequate maintenance and emergency access should be reserved.
• The installation foundation should meet the equipment load requirements.
• Ventilation and fire-safety requirements should be evaluated before installation.

Electrical Supply

The standard electrical requirement stated for the equipment is three-phase AC 380 V, 50 Hz. The final electrical configuration should be confirmed according to the destination country and project requirements.

Pretreatment Requirements

Dust, oil mist, sticky substances and catalyst-poisoning compounds may reduce catalytic activity or block the heat-storage media.

Depending on the actual exhaust gas conditions, the following pretreatment equipment may be required:

• Dust filters
• Oil mist separators
• Spray scrubbers
• Condensers
• Demisters
• Activated carbon concentration systems
• Zeolite rotor concentrators

Why Choose ES Air RCO Series?

• Designed for medium- to high-concentration industrial VOC exhaust gas
• High VOC removal and heat recovery efficiency
• Lower oxidation temperature than direct thermal combustion
• Low fuel consumption under suitable VOC concentrations
• Two-chamber and three-chamber configurations available
• Suitable for changing VOC composition and concentration
• Optional waste heat recovery for production reuse
• Fully automatic PLC operation
• Customized process design according to actual working conditions

Frequently Asked Questions

What is a regenerative catalytic oxidizer?

A regenerative catalytic oxidizer is an industrial VOC treatment system that combines catalytic oxidation with ceramic regenerative heat recovery. It oxidizes organic pollutants at a relatively low temperature and reuses the heat from the treated gas.

What VOC concentration is suitable for the RCO series?

The RCO series is generally designed for medium- to high-concentration organic exhaust gas, typically around 1,000–10,000 mg/m³. The final suitability depends on VOC composition, airflow and calorific value.

What is the difference between RCO and RTO?

RCO uses a catalyst to reduce the required oxidation temperature, while RTO relies on higher-temperature thermal oxidation. RCO can reduce fuel consumption but requires stricter pretreatment to protect the catalyst.

Can the RCO operate without continuous auxiliary heating?

Under suitable VOC concentration and calorific-value conditions, the oxidation heat released by the exhaust gas may maintain the required operating temperature after startup, reducing or eliminating continuous auxiliary heating.

Why is catalyst protection important?

Dust, heavy metals, phosphorus compounds, sticky oil mist and other contaminants may poison or block the catalyst. Suitable pretreatment is required to maintain catalytic activity and service life.

Can waste heat be reused?

Yes. Optional heat recovery equipment can use the treated gas heat for drying lines, process hot air, hot water or other production requirements.

Can ES Air customize the RCO system?

Yes. ES Air can design the system according to airflow, VOC concentration, chemical composition, temperature, humidity, dust content, heat recovery requirements and local emission standards.

Customized Regenerative Catalytic Oxidation Solutions

ES Air provides regenerative catalytic oxidation systems and integrated VOC treatment solutions for coating, chemical, printing, rubber, cable and industrial drying applications.

System selection should be based on exhaust gas volume, VOC concentration, pollutant composition, calorific value, temperature, humidity, particulate content and required treatment efficiency.

Contact ES Air for working-condition evaluation, process design, equipment selection and customized RCO solutions.

SEO Brief: The ES Air RCO Series Regenerative Catalytic Oxidizer is designed for medium- to high-concentration industrial VOC exhaust gas. It combines low-temperature catalytic oxidation, ceramic heat recovery and PLC automatic control to achieve high VOC removal efficiency and reduced fuel consumption. The system is suitable for automotive coating, shipbuilding, chemical, rubber, printing, cable, paint and industrial drying applications.