Adsorption wheel
With an adsorption wheel (also: adsorption rotor), large volumes of exhaust air with low organic loads can be treated at significantly lower cost than with thermal processes.
Adsorption Rotor for Exhaust Air Treatment
An adsorption rotor is used to remove and concentrate volatile organic compounds (VOCs) from exhaust air streams. It is particularly suitable for large exhaust air volumes with low pollutant concentrations. Contaminated air passes through a rotating wheel containing highly porous adsorption media, where the pollutants are captured on the surface. Through continuous regeneration, the adsorbed substances are released again and concentrated into a much smaller air stream. This allows downstream exhaust air treatment systems to operate more economically and helps reduce operating costs. Adsorption rotors are used in industries such as painting and coating, chemicals, and other solvent-based production processes.
Eisenmann Environmental Technology designs and delivers adsorption rotor systems as part of efficient exhaust air treatment concepts. Each system is individually engineered to suit the specific process conditions, pollutant loads, and requirements for energy efficiency and emission reduction.
At your side through every project phase
From our experienced team, you receive everything you need for your highly efficient exhaust air treatment — from design and manufacturing through to after-sales service. We always keep your specific production environment in focus. Where standard products are not sufficient, we develop our own solutions.
Depending on your needs, we can combine the adsorption with thermal or regenerative thermal oxidation systems as well as with a steam boiler or combined heat and power unit. Let us advise you in detail and align all measures with your operational processes.
How our adsorption wheel works
Unlike thermal processes, adsorption does not convert pollutants and requires almost no temperature increase. Instead, this physical process uses solid materials such as activated carbon or zeolite. These have the property of accumulating gases or vapours on their surface — i.e. adsorbing them.
Our adsorption wheel consists of chambers arranged concentrically around an axis. Exhaust air is fed to the adsorption material contained within.
This is followed by desorption in a sealed section of the rotating adsorption rotor, where the accumulated pollutants are driven off again. Hot air is directed in counterflow over the adsorption material. Since this air stream is more highly concentrated and has a lower volume, it can be thermally oxidised in a significantly more cost-efficient manner.
Your benefits
- Very large exhaust air volumes: The adsorption wheel from Eisenmann Environmental Technology processes lightly loaded exhaust air volumes of up to 200,000 Nm³/h per unit.
- Reduced volume flow: The desorption air stream is up to 40 times more concentrated and correspondingly lower in volume. This allows the exhaust air to be treated more cost-effectively.
- Less primary energy: Thanks to the high solvent concentration, adsorption reduces the use of primary energy sources such as natural gas.
- Lower concentration peaks: Due to the high absorption capacity of the adsorption bed, our system buffers concentration peaks.
Need advice?
Simply get in touch with us by phone or email. We will be happy to inform you about your options for the adsorption wheel and develop your optimal solution.
Frequently asked questions about adsorption wheels (ADW)
What is an adsorption wheel?
An adsorption wheel concentrates volatile organic compounds (VOCs) from industrial exhaust air. To achieve this, the rotating adsorption medium, typically made of zeolite, captures the pollutants and subsequently releases them into a much smaller air stream. This enables downstream air pollution control systems, such as regenerative thermal oxidizers (RTOs) and thermal oxidizers (TNVs), to operate more efficiently and with lower energy consumption. Adsorption wheels are primarily used for applications with high exhaust air volumes and low VOC concentrations.
How does an adsorption wheel work?
An adsorption wheel consists of a rotating zeolite rotor divided into adsorption, regeneration, and cooling sections. In the adsorption section, the zeolite material captures VOCs from the exhaust air stream. In the regeneration section, a heated air stream desorbs the pollutants from the zeolite. This process creates a much smaller, highly concentrated exhaust air stream. The concentrated air stream is then directed to a thermal oxidation or thermal treatment system for destruction of the pollutants. As a result, the system removes VOCs efficiently while reducing overall energy consumption.
What applications are adsorption wheels suitable for?
Adsorption wheels are particularly suitable for industrial processes with high exhaust air volumes and low to moderate VOC concentrations. Typical applications include paint shops, coating lines, printing facilities, battery production plants, and electronics manufacturing. Companies use this technology to reduce emissions while lowering energy consumption and operating costs. Eisenmann Environmental Technology designs and supplies adsorption wheel systems for a wide range of industrial applications, tailoring each solution to the specific requirements of the customer’s process.
What pollutants can be treated with an adsorption wheel?
Adsorption wheels are primarily used to remove and concentrate volatile organic compounds (VOCs). These include a wide range of solvents such as alcohols, ketones, esters, and aromatic hydrocarbons generated during industrial manufacturing processes. Whether a specific substance can be treated depends on its chemical properties and the operating conditions of the system.
When is it worthwhile to use an adsorption wheel?
An adsorption wheel is particularly cost effective when treating large exhaust air volumes with low VOC concentrations. In such applications, direct thermal air pollution control can require significant energy input. By concentrating the pollutants, the adsorption wheel significantly reduces the volume of air that needs to be treated. This helps lower both capital investment and long term operating costs.
How does an adsorption wheel reduce energy consumption and operating costs?
An adsorption wheel concentrates VOCs contained in large exhaust air streams into a much smaller air volume. As a result, the downstream thermal air pollution control system only needs to treat a fraction of the original airflow. This reduces fuel consumption and improves the overall energy efficiency of the system. In many applications, adsorption wheels therefore play a key role in lowering operating costs.
Can an adsorption wheel be combined with an RTO or TNV?
Adsorption wheels are frequently combined with regenerative thermal oxidizers (RTOs) or thermal oxidizers (TOs). The adsorption wheel concentrates the VOCs, while the thermal treatment system oxidizes and destroys the pollutants. This combination provides an economical and energy efficient solution for air pollution control, even when treating large exhaust air volumes with low pollutant concentrations. Eisenmann Environmental Technology integrates adsorption wheels as part of comprehensive air pollution control systems and combines them with downstream technologies to meet specific process requirements.
What is the difference between an adsorption wheel and an activated carbon filter?
An activated carbon filter stores VOCs in the filter media until its adsorption capacity is exhausted. The activated carbon must then be replaced or regenerated. In contrast, an adsorption wheel operates continuously and regenerates itself during operation. This makes it particularly suitable for high exhaust air volumes and continuous industrial processes. Activated carbon filters are often used for smaller airflows, while adsorption wheels are primarily used to concentrate VOCs before downstream thermal air pollution control systems.
Can an adsorption wheel be integrated into existing air pollution control systems?
In many cases, an adsorption wheel can be integrated into existing air pollution control systems. In particular, adding VOC concentration upstream of existing RTO or TNV systems can significantly reduce energy consumption. The feasibility of a retrofit depends on the specific process conditions and system parameters. Eisenmann Environmental Technology evaluates existing system designs and develops customized retrofit solutions to improve energy efficiency and make optimal use of existing plant capacity.
What factors affect the performance of an adsorption wheel?
Several factors influence how efficiently an adsorption wheel operates. These include VOC concentration, exhaust air volume, pollutant composition, temperature, and humidity. Dust and other airborne contaminants can also affect performance. Careful system design and engineering ensure that the adsorption wheel achieves high removal efficiency and reliable long term operation. Eisenmann Environmental Technology takes all relevant process parameters into account during system design to ensure the adsorption wheel is optimally matched to the requirements of each application.