Why treat the kitchen exhaust air?
Air discharged from commercial kitchens and restaurants, especially kitchens where deep fryers are used frequently, contain large amounts of grease in the cooking fumes.
The fumes contain heat energy, odor molecules, soot and grease particles. The heat causes the grease to take either liquid form, gaseous form or in form of aerosols.
The kitchen ventilation should provide a good working environment by venting the cooking fumes, heat and odors from the kitchen while simultaneously supplying fresh air. Ideally, the ventilation system should ensure that the rest of the property and surroundings are not negatively affected by the kitchen operations.
The illustration below shows an exhaust ventilation in a commercial kitchen without ozone treatment.
The large grease particles are separated and entrapped by an air filter in the kitchen hood. The air then continues through the ventilation duct with odors and smaller airborne grease particles. Without efficient and continuous air purification, these will follow the exhaust air flow through the entire duct and adhere to the duct walls, the fan, the heat exchanger and the pre-filter of the heat exchanger. A small part remains airborne and passes into the environment like odor.
Over time, fat deposits are generated in the kitchen ventilation. Grease is a very energy-rich fuel and constitutes, therefore, a large and real fire hazard if ignited. Learn more about how to increase fire safety.
Odors emitted from the ventilation exhausts to the surroundings can cause complaints from residents and businesses. These complaints may lead to authorities forcing the person in charge to take immediate action. Learn more about how to reduce odor problems.
Restaurants and kitchens with equipment such as deep fryers, grills, woks or griddles need a reliable, high capacity purification system that continuously purifies the air from grease.
Purifying the exhaust air and kitchen duct enables:
- Optimized heat recovery
- Increased fire safety
- Less odor problems
- Possibility to utilize cheaper ventilation material
- Lower operational costs
- Reduced environmental impact
Hot purified air is a valuable asset that directly affects the energy consumption of the property
As an example, a restaurant with an exhaust air flow of 5,000 m3/h (i.e. 1380 l/s) loses energy approximately worth 13,500 EUR per year.
Utilizing efficient purification of the exhaust air, up to 82% of energy can be recycled and large sums saved. See the diagram on the right.
Read more about how to efficiently minimize grease in the exhaust air.