Odour Control: Solving the problem of sticky particulates in a high temperature frying environment
Odour that extends beyond the boundaries of a production facility and causes a nuisance to the surrounding area is considered pollution and can negatively impact the lives of employees and those living nearby. The Environment Agency holds the power to serve notices on companies not dealing with odour issues adequately, outlined in its H4 Odour Management Guidelines.
Odour Issues in high temperature frying environments
Odour issues can be found in the production of ready meals; frozen food; spices; sauces; meats; and seafood. High temperature cooking/frying is commonplace in these sectors, as this can reduce cooking time and increase production efficiency, but the process can cause odour to be emitted into the atmosphere. The odour comes from the food itself, the coating or the oil that it is fried in.
Most commonly, the oil mist comes from when the food is fried and thermal breakdown takes place under the high temperatures. This can cause issues not only with odour but also acridity, which can be dangerous for both workers and the wider community. Odours that are acridic in nature can be harmful in high quantities, particularly to the back of the throat. In addition, the oil can create coatings in the factory environment, damaging machinery, and the oil and steam mist can be incredibly sticky to walk on. Sticky oil particulates can also be flammable. If appropriate extraction is not in place, there is a risk of fire in the extraction ducts, and any fire damper installation can become ineffective as the particulates are too sticky.
Odour control management is therefore an essential part of operations in a high temperature cooking environment.
A solution that solved the issue of sticky particulates
Traditional odour control measures can be ineffective in a high temperature frying environment, due to the sticky particulates that form part of the emissions. Centrifugal or standard impingement wet scrubbers are often a go-to solution in these environments, however their suitability varies as they are not effective at dealing with sub-micron particulates and the standard mist elimination can be inadequate, with no gas scrubbing phase included to remove odour at this stage.
When FEG was asked to solve an acrid odour issue for Whitby Seafoods, the first stage was a full survey to understand the exact requirements. Questions asked included the type and quantity of particulates in the air, the nature of the odour issue, gas analysis if required, water consumption, trade effluent permit limits, type of system (i.e. once-through or recirculatory), and what was required to control the contaminant at the point of release and efficiency of the machinery.
The seafood manufacturer was dealing with a complaint about the acrid odour in the neighbouring community and required a solution that would both integrate with existing factory processes and solve the odour acridity issue.
Gas/Odour emissions were analysed and the exact contaminants were identified, specific to the high-temperature frying process. It was quickly evident that a standard scrubber solution would not prove effective due to the sub-micron sticky particulates and gas phase contaminants.
Liquid Gas Scrubber Installation
Our patent-pending Liquid Gas Contact Scrubber (LGC) was specified and installed as the solution. The flexible and modular multi-stage scrubber system proved an ideal solution as, unlike other scrubbing solutions, the LGC can cope with both particulates and gas phase odour – solving the issue of sticky particulates that are typically difficult to remove in high temperature cooking facilities.
The unique design of the scrubber ensures a practical and low maintenance solution, suitable for internal or external installation and with no cleaning of ducts. Recirculation of liquor reduces costs and lowers environmental footprint and the system tackles legionella, ensures BAT (Best Available Techniques) compliance and can incorporate CIP systems. It also provides a fire barrier accepted by insurance companies.
The flexible, modular nature of the LGC meant the FEG team was able to deliver a tailored approach and a cost-effective solution for our client, successfully removing the acridity issue for the client so that they could continue production in confidence. As part of the project the team also designed and installed a PLC system.
Our team is an experienced provider of air pollution and odour control systems, operating at Principal Designer/Contractor level when required.