Controlling VOC emissions in wood furniture production
Controlling and reducing VOC emissions present a significant challenge for the wooden furniture industry.
In this case, a factory making kitchen furniture was producing VOC emissions ranging from 250 to 1 500 mgC/m3, yet needed to abide by a legal limit of just 75 mgC/m3.
DESOTEC provides mobile filters for several wooden furniture companies. Solutions are modular and flexible, meaning they can be adapted to the changing needs of each particular factory, the chemicals it uses, and the policy landscape in which it operates.
At the kitchen furniture site in question, an Aircon V-XL filter was chosen as the optimal system and is now operating effectively, maintaining VOC emissions under the limit.
VOC extraction systems for use in the production of wood furniture must be capable of dealing with several key issues.
Firstly, there are a number of manufacturing stages during which VOCs can be emitted: for example, glueing, painting, laminating and varnishing. That means that there may be diverse areas of a factory from which VOCs must be removed at different stages of the production process, such as spray booths and paint spraying walls.
There is also a range of chemicals used, among the most common and potentially harmful of which are butyl acetate and xylene.
Finally, the concentration of emissions fluctuates during the different stages of the production process.
Therefore, any VOC extraction system must be capable of managing discontinuous production, several different VOC sources, a variety of chemicals, and a wide range of concentrations.
At our client’s kitchen furniture factory, there are four locations emitting VOCs: two drying ovens and two paint spray booths. The furniture is made of composite wood, which contains glues and resins, while the finishes include paints, laminates and varnishes.
A range of VOCs is emitted at different stages of the manufacturing process, necessitating the installation of a solution that is both robust and scalable.
The customer chose DESOTEC’s Aircon V-XL mobile filter system due to its flexibility and efficiency. This model is capable of handling a flow rate of 5 500-55 000 m3/h. It contains R-PURE activated carbon to adsorb VOCs. The impurities stick to the surface of the carbon's pores until the filter is saturated.
In the case of the kitchen furniture factory, all four emissions sources were combined into one single extraction system. Automatic control valves were installed so the filter extracts VOCs only during the relevant stages of the production process.
A Flame Ionization Detector (FID) was also fitted, which continually measures the concentration of VOCs in the purified gas so that the client knows when the filter is becoming saturated and can plan for an exchange from DESOTEC.
Changing a mobile filter is relatively simple and takes around just one hour – unlike changing a fixed filter, which is a far lengthier and more complicated process.
To make the connection easier, the filter is plugged to a fixed docking station, the AIRCONNECT patented system from DESOTEC. It allows changing the activated carbon filter without connecting and disconnecting the inlet and outlet piping, hence saving time and man-effort.
The DESOTEC truck manoeuvres the replacement into position. The driver then transports the saturated filter away from the site to DESOTEC, removing the risk to clients of handling any contamination from the spent carbon.
The kitchen furniture plant in question produces VOC concentrations ranging from 250 to 1 500 mgC/m3. Despite these fluctuations, and the discontinuous operation of the plant, the Aircon V-XL is able to operate smoothly, keeping emissions within the legal limits of just 75 mgC/m3. It handles a flow rate of 38 000m3/h – well within its capacities.
To ensure safe operation, a hotspot detector has also been fitted, which prevents fires in the filter's carbon bed by closing down the system and flushing it with an inert gas if it detects carbon monoxide in the purified gas. The filter is then left to cool and can be restarted after a day.
This is just one example of DESOTEC’s mobile activated carbon filters in action. Talk to the team today to find out how they can help your business.
At DESOTEC’s facilities, all used carbon is analysed so the right measures can be taken for handling and removing the saturated carbon out of the mobile filters. All molecules that were adsorbed on the activated carbon at the customers’ site, are desorbed inside DESOTEC’s reactivation furnaces. These contaminants are then fully destroyed, in accordance with National and European legislation, by an incineration and neutralisation setup. The entire installation and it's emissions are under continuous on-line monitoring, which guarantees that only harmless water vapour is seen exiting the chimney.