Safe odour treatment at a food processing plant

1. DESOTEC provides expert and clear advice to customers about safe filter operation.
2. We work with our partner Lybover to boost safety by ensuring sufficient ventilation on site.
3. Our full-service solutions include safe off-site waste handling, keeping clients’ sites clean and dust-free.

This Belgian fish smoking company was subject to odour complaints from neighbours. It contracted a specialist odour advisory company, who recommended treating emissions from the three smokehouse ovens through activated carbon filtration.

The client contacted DESOTEC about our mobile filtration solution, but decided at that time that a fixed filter from a third party would better suit its needs.

However, production at this site is in batches, so air flow through the filter is discontinuous. This can lead to hotspots developing in the filter bed, which are fanned when the air flow is restarted.

Furthermore, the air emissions come directly from the smoking ovens, making them humid and sooty. A dust filter placed before the activated carbon filter became clogged.

After around a year, this fixed filter caught fire during operations. Fortunately, nobody was hurt in the incident, and staff were able to protect the building and nearby equipment.

However, the fixed filter (made from plastic) and associated piping were completely destroyed, so the company needed a new, safe treatment solution. It got back in contact with DESOTEC.

We explained to the client the hotspot risk related to discontinuous flow in activated carbon filtration systems, and advised operating filters under continuous ventilation in the future.

We then worked with our engineering partner Lybover to install a safe and efficient treatment set-up.

DESOTEC supplied an AIRCON 2000 filter (made of stainless steel) containing B-Pure 10-NB carbon to treat the flow from the ovens. Unlike many food production applications, flow rates are low (1400m³/h) and concentrations of odorous molecules are high.

Lybover installed the ducting and extra ventilation to reduce the humidity and temperature of the air emissions.

This system almost eliminates the risk of hotspots developing. However, DESOTEC also ensured that the client knew how to monitor and prevent any further incidents.

One option was to install our specially developed Inerti-box, which detects hotspots and automatically douses them with nitrogen. However, it was decided that the client could instead connect the filter to a water source and flush the carbon bed in the highly unlikely event of a hotspot developing.

The filter has been operating since July 2024 without issue. There have been no odour complaints from neighbours.

It will require exchange in roughly a year’s time. The client has chosen to exchange it in spring, so that there will be a fresh filter in place for the warmer months when any odour emissions would be worse.

The filter exchange will be quick and easy thanks to its plug-and-play system, requiring only 30 minutes and no production downtime – a fact that is appreciated by the client, who had to empty and refill the previous fixed filter itself.

DESOTEC technicians will transport the closed filter off-site. This process is dust-free, making it ideal for food production and processing companies, where cleanliness is paramount.

The filter will be emptied at our site, where we have the necessary safety precautions and trained staff to handle any risk of hotspot.

The spent carbon will then be thermally treated in our furnaces, where all adsorbed molecules will be completely destroyed. The carbon may then be reactivated for reuse, increasing the sustainability of this solution.