Thermal Oxidizers

Thermal Oxidizers, Incineration Systems, Waste Heat Recovery, and more

speciality thermal oxidizers

Incineration is a thermal process for converting waste gases or liquids to an environmentally acceptable condition. Our systems are capable of achieving 99.9999% destruction efficiency. The basic incineration system is comprised of an auxiliary fuel burner, a refractory-lined chamber, a discharge vent stack, and a control system. These components are described below.

Auxiliary Fuel Burner

This burner is provided to maintain the system operating temperature at the level necessary to achieve the desired performance. The burner can be fired with either gaseous or liquid fuel. The burner design is an integral portion of the incineration system design to provide the proper heat release profile and flame envelope to assure proper destruction of the waste gases or liquids.

Refractory Lined Chamber

Waste gas or waste liquid incineration requires that the incoming waste be treated (1) at a high temperature (typically 1200 to 2000°F), (2) for a minimum residence time (typically 0.5 to 2.0 seconds) and (3) in an environment to ensure proper turbulent mixing of fuel, air, and waste. To meet these requirements, a steel vessel lined with high temperature refractory is provided. The vessel size and refractory materials are selected to be compatible with the waste stream and to meet the basic time, temperature, and turbulence requirement.

Discharge Vent Stack

A vent stack transports the flue gas exiting the incinerator to the atmosphere. The vent stack height is fixed by flue gas dispersion requirements to avoid interference with other plant structures or operations. Vent stacks available separately.

Control System

An automatic control system is an integral portion of each incinerator. The control system assures that the unit will be operated in a safe manner to protect both personnel and equipment. To meet performance objectives, the waste combustion is performed under controlled and repeatable conditions. Typically, the control system monitors and actively controls flue gas temperatures, combustion/quench air flows, fuel pressures/flow, and flame stability to ensure safe and consistent equipment operation.

Wide shot of a Specialty Thermal Oxidizer

Packaged Incineration Systems

Zeeco’s packaged thermal oxidizers are available off the shelf or for rental applications, and can be delivered in as fast as a week. Mounted on a prepiped, prewired skid, our units require only minimal field assembly for fast installation. Quick response, on-site engineering, 24/7 support, and technical consultation are always available, even after installation.

Design Features

  • ZEECO burner specifically designed for acid gas, glycol vent gas, flash gas
  • ZEECO Burner Management System (BMS) PLC, instruments, controls, and HMI at local control panel
  • Combustion air blower with variable frequency drive
  • Full rain shield prevents acid gas condensation
  • Greater than 99.999% DRE
  • NFPA 86 compliance

Options Available

  • Detonation arrestor
  • Knockout drum
  • Waste block valves
  • Process control system (minimal outside control interface required)
  • ZEECO Guardian™ Wireless Remote Monitoring System (cellular accessibility)
  • Ladders and platforms
  • ZEECO ultra-low NOx burners

AIR Heaters

A Direct Fired Air Heater effectively heats air, as needed in a variety of heating processes. This equipment is most commonly employed in Fluidized Catalytic Cracker (FCC) units in petroleum refineries. The direct-fired air heater is primarily intended to be used during start-up operations and short feed outages to heat the catalyst bed in the regenerator section of the FCC unit (catalyst regeneration). During normal operation, the air heater is not fired and air flows directly to the regenerator through the air heater without being heated. The mass flow rate and operating pressure during the un-fired condition may vary from that used during the fired case. 

Exterior of Air Heater on a trailer

waste heat recovery

Waste heat recovery equipment reclaims heat from flue gas for use in other process units. The heat is transferred directly from the hot flue gas to a steam boiler or circulating thermal oil system. The quantity of flue gas and the associated exit gas temperature limit the amount of heat recovered. These systems can typically recover up to 70-80% of the theoretical heat available in the flue gas. System heat recovery ranges in size from 1.0 MM Btu/hr to 300MM Btu/hr.

A primary advantage of waste heat recovery is the production of usable heat without any additional fuel expense. Because the waste heat recovery equipment draws heat from flue gas that would normally be discharged to the atmosphere, all heat recovered can be utilized to offset the fuel required to produce process heat in other facility operations. Zeeco waste heat recovery equipment improves overall plant economics and plant efficiency.

Exterior shot of a Waste Heat Recovery System

Post-Combustion Treatment

The goal of any incineration or thermal oxidation process is to control the amount volatile organic compounds (VOCs) released to the environment. While these systems typically achieve high destruction of VOCs, additional air pollutants may be generated during combustion of certain compounds in the waste stream. If released to the atmosphere without further treatment, these compounds can form secondary air pollutants.

Zeeco provides a variety of proven, environmentally beneficial solutions for post combustion treatment. Depending on the application and the components of the flue gas, one or more devices can be incorporated to form a compact waste treatment system:

  • Wet Scrubbers for HCI Removal
  • Wet Scrubbers for SO2 Removal
  • Baghouses (Fabric Filters) for Particulate Removal and Acid Gas Scrubbing
  • Venturi Scrubbers for Particulate Removal and Acid Gas Scrubbing
  • Selective Catalytic Reduction (SCR) for Post-Combustion NOx Removal
  • Selective Noncatalytic Reduction (SNCR) for Post-Combustion NOx Removal
  • Options for Catalytic Reduction of Dioxins and Furans
Post Combustion Treatment

Vent Stacks

Vent Stacks are used to discharge gasses to the atmosphere at a safe and environmentally friendly elevation. The required elevation and discharge velocity is dictated by a variety of design parameters. These include the vent stack’s location and surrounding structures as well as the vent gas temperature, constituents, allowable ground level concentrations, odor threshold, corrosion requirements and structural integrity. Structural integrity should consider all possible live loads, earthquake and wind conditions. 

Design Configurations: 

  • Single or double wall
  • Self, derrick or guy wire supported
  • Internal refractory lining or external insulation
  • Carbon steel, alloy, fiberglass construction
  • Strakes, tuned mass damper, or damping pad
  • Retractable or fixed aircraft warning lights
  • Rainshield material galvanized, aluminum, stainless
  • Ladders and platforms

Design Codes:

  • Any globally applicable design code, such as:
    • ASME STS-1
    • CICIND
    • IS 6533

Additional Features:

  • Custom thermal design to prevent corrosion
  • Single or multiple piece lift configurations available
Crane lifting a Vent Stack into place


At Zeeco, we understand the vital role thermal oxidizers, also known as incinerators, play in the destruction of hazardous waste gases. It's one reason we maintain a wide inventory of parts and critical components for ready for immediate shipping. Need on-site repair? Our global Rapid Response Team is as experienced and knowledgeable as they come and equally committed to returning your product to service in the shortest amount of time. Zeeco also offers emergency rentals when the unexpected occurs to get your operation back online fast.

  • Complete parts inventory for every thermal oxidizer / incinerator system with overnight delivery available
  • Rapid Response Team for emergency diagnostic service and repairs
  • Global technical services, including preventive maintenance, installation and commissioning
  • Emergency rentals
  • Thermal oxidizer/incinerator system training


Zeeco can provide combustion and emissions control solutions wherever hydrocarbon processing takes place. Customers can find our equipment and services in upstream, midstream, and downstream oil and energy processes.

We also offer products and support for other industries and applications such as tank/terminal loading and storage, pharmaceutical, carbon black, pulp & paper, steel, food processing, and more.