Undesirable odours may occur due to the process, as well as the problems that arise in the operation of the facility and the insufficiency of operation. Odour control methods can be discussed under two separate headings.
PS: We did not mention the ozone method in this article. There are many articles about the ozone method on our site, you can read them.
When the facilities that cause bad odours are examined, it is seen that the source and structure of the odours and the methods that can be applied to prevent them may vary according to the type of these activities. Below are the activities that cause odour formation the most and the prevention methods that can be applied in these areas.
The way of working and the physical structure of these facilities greatly affect the formation of odour. In this respect, the most appropriate way to prevent odour formation is to establish and operate these facilities according to certain standards. There are guides prepared by various institutions and organizations for such facilities, which attach great importance to odour formation.
When odour pollution control and removal is approached according to the principles of clean production and prevention of pollution at its source, it is seen that preventing the formation of odour is more effective and preferable than methods such as purification or applying a safety distance. When approached from this point of view, odour prevention methods are stated as follows, in decreasing order of preference according to the nature of the measure:
Preventing odour before it occurs will be a more economical and effective method. This can be done by improving the production structure and operating conditions of the facility.
Use of appropriate raw materials: Choosing raw materials that will not cause odour formation among alternatives. The possible cost difference should be evaluated by considering the treatment cost.
Proper raw material and waste storage: Making warehouses and storage conditions at certain standards is one of the methods that most affect the formation of odour. It is especially important in the food and livestock and livestock industries.
Prevention of leaks: Performing operations in closed environments as much as possible, preventing leaks in pipes and boilers, collecting and purifying odorous process gases. (Good Housekeeping).
Purification: Purification of odorous gases and liquids from odour-forming compounds. For this, in addition to general purification techniques, original techniques are used.
Condensation is a technique for separating solvent vapours or other odorous gases from the waste gas by lowering their temperature below their dew point. In odorous gases, the water, which is separated from the water-saturated gas by condensation, acts as an absorber in the odorous gases and in this way the odorous gas is purified.
The application limit for odorous gases is 100,000 odour units/Nm3.
Adsorption is a heterogeneous reaction in which gas molecules are attached to solid surfaces that favour certain compounds over others and are thus separated from the liquid.
It consists of the breakdown of bacteria as a certain quality of the gas consumed by passing through the odorous gas environment around it. In the continuation of such investments, the design is not as important as ensuring the management and winning. The temperature rise is related to the humidity and temperature condition of the filter medium and the residence time of the gas.
Bio washing combines wet scrubbing with biodegradation. Here, the wash water contains populations of bacteria that can oxidize the odorous gas components. For this, the waste gas content must be washable and the washed components must be biodegradable under aerobic conditions.
Bio drip works in the same conditions as bio wash. Unlike bio washing, the bacterial population is attached to support elements, i.e. a bedding material. Here, the liquid is circulated through a bed of inert materials.
Thermal oxidation is the process of oxidation by heating the mixture of odorous gases in the waste gas stream, together with air or oxygen, in a furnace to a temperature above the flash point and maintaining a high temperature for a sufficient time to cause complete combustion to turn into carbon dioxide and water.
Catalytic oxidizers work much like thermal oxidizers. The biggest difference is that the gas passing through the flame zone also passes through a catalyst bed. The catalyst increases the rate of the oxidation reaction, allowing it to take place at lower temperatures. This allows the use of smaller oxidizers.
Comparison of Efficiency of Various Treatment Techniques
Odour Control Efficiency (%)
Bio – washing
Bio – drip