How to Remove Emissions in the Food Production Industry

It comes without saying that odours are the main course on the food industry’s pollution menu. This is particularly true for industrial plants located nearby residential areas. Many plants such as slaughterhouses, pet food and animal feed factories, coffee roasters, and breweries often receive odour complaints from their neighbours. The smelly ingredients giving off odour nuisance include volatile organic compounds (VOCs), ammonia (NH3), and dihydrogen sulfide (H₂S). 

To remove these odours, food businesses can harness the best available technologies (BAT) such as activated carbon filtration. In particular, standard or impregnated activated carbon can trap VOCs or inorganic odorous molecules into their pores.

Safe odour treatment at a food processing plant

A Belgian fish smoking company was subject to odour complaints from its neighbours. To resolve this issue, they initially opted for a fixed filter from a third party. However, after a year, the fixed unit caught fire during operations. This likely occurs because of the discontinuous production, often leading to hotspots developing in the filter bed, which are fanned when the air flow is restarted. Given that the fixed filter (made of plastic) and associated piping were completely destroyed, the company reached out to DESOTEC for a safer odour removal solution. We supplied an AIRCON 2000 filter (made of stainless steel) and installed our specially developed Inerti-box, which detects hotspots and automatically douses them with nitrogen. Since then, the filter has been operating seamlessly and there have been no odour complaints from neighbours. Read more.

Odour removal from slaughterhouses

A family-owned company in the Netherlands runs a slaughterhouse where pork is processed. The site includes closed tanks where intestinal waste is stored before being converted into fertiliser or destroyed, with vents to release the gases from the decomposition process. A bioscrubber was in place to remove odours from air emissions, but this was proving insufficient. As the factory is situated on the edge of an urban area, people living nearby complained both to the company and the environmental authorities about the odour nuisance. To eliminate odorous compounds (ammonia, dihydrogen sulphide (H₂S), dimethyl sulphide (DMS) and mercaptans) from their air emissions, the company tapped into DESOTEC’s expertise. As the flowrate to treat was very low (300 m³/h), we recommended our smallest filter, i.e. the AIRCON 2000. This proved to be very effective, removing 99% of the odorous molecules, thus satisfying both environmental authorities and those living near the site. Read more. 

Chemical oxygen demand (COD) includes a series of substances (both biodegradable and non biodegradable) which can be removed via oxidation. These encompass pesticides and POPs, among others, and are released into wastewater when rinsing food. If not removed from wastewater, COD will harm marine wildlife. In addition to this, COD could also disrupt bacteria in wastewater treatment biofilters. 

Activated carbon filtration is a BAT to decontaminate food production or processing wastewater from COD. Relying on the adsorption mechanism, activated carbon is able to capture these contaminants, which are not efficiently removed by biological treatments.

Reducing wastewater COD levels at plastic recycling company

An Italian company recycles plastic food packaging. The washing and recycling processes result in wastewater containing a COD concentration of around 600 mg/L. When increasing its rate of production, the client found that its fixed activated carbon filters were unable to cope. DESOTEC converted the client’s unit to use sand, which filters out the suspended solids from the wastewater. Next, a MOBICON mobile filter was installed, thus reducing the COD levels to 150 mg/L. Read more.