Revealing the Deodorizing Device of Pig Farms: Technology Makes Animal Husbandry More Environmentally Friendly

In the past two years, the environmental protection requirements for breeding enterprises in China have become increasingly high, especially in terms of exhaust emissions. It is required to install odor collection and treatment facilities and equipment at key nodes such as pig houses and manure treatment, and implement full monitoring and management of air quality in the farm to reduce odor gas emissions. Therefore, major aquaculture enterprises have added exhaust emission purification and deodorization equipment in both new and ongoing projects this year.
It can be foreseen that in the coming years, with the gradual recovery of pig production capacity, various places will put forward requirements for the exhaust emissions of breeding farms.
Although deodorization equipment has been used abroad for many years, it is still relatively unfamiliar to most domestic breeding enterprises. Based on the deodorization equipment that has already been put into use, this article provides a brief introduction for industry reference.
The principle of deodorization equipment
The principle of deodorization equipment used in pig farms is relatively simple, similar to the packing tower principle of industrial deodorization equipment. It allows the odor to pass through the packing, allowing the odor components to fully contact the spray liquid, and using the liquid phase to absorb the gas phase. Because the main components of the odor in pig farms are ammonia and dust, which are relatively soluble in water, they can achieve deodorization effects.

Structure of deodorization equipment
At present, most of the horizontal equipment in China adopts single-layer filter walls. The deodorization wall is erected 5-6 meters away from the fan outlet, which has a lower cost. The equipment generally consists of five main parts: filter material, outer enclosure, reservoir, sprinkler device, and electrical control. In addition, water quality monitoring and regulation systems can be added to increase the automation level of the equipment.
1. Filter material and filter material fixing frame (main core part)
Filter material is the core material of deodorization equipment. Currently, the main materials used are grid shaped filter material and spherical filter material, both of which are injection molded from PP plastic. Grid filter material is stacked in pieces to form modules, and stacked on site to form walls. Ball filter material is made into a basket shaped container, which disperses and piles up the filter balls.
Grid filter material is a type of filter material specially developed for ventilation and deodorization in aquaculture farms. Its characteristics are small wind resistance (less than 10Pa when unloaded), low static pressure requirements for fans, convenient installation and fixation, and no need for maintenance during use. The price of ball packaging materials is low, but the relative wind resistance is high (35Pa), which requires high static pressure of the fan. Additionally, the spherical filter wall is prone to dust accumulation and requires regular disassembly and cleaning after long-term use.

2. Civil infrastructure such as external enclosures and water tanks
Flat level pig houses are generally surrounded by steel structures, which have a lower cost and faster construction speed. However, the sealing effect is not ideal, and it is easy to leak some untreated odor. The pig houses in buildings are all constructed with deodorization rooms added to the civil engineering structure, using brick concrete or concrete structures. This type of structure has good sealing performance, long service life, and higher cost than steel structures.
3. Circulating spray device (spray cleaning)
The main components of the circulating spray system are the centrifugal water pump, spray pipeline, and spray nozzle.
The spray water pump needs to use a corrosion-resistant stainless steel pump head, both vertical and horizontal can be used; The spray pipeline adopts UPVC water supply pipe, with a pressure requirement of 1.0Mpa; The spray nozzle adopts a spiral nozzle that is not easily clogged.
4. Electronic control system
The electric control system mainly controls the opening of the water pump. In order to control the spray pressure and adjust the flow rate of the water pump, variable frequency control will be used.
5. Water quality monitoring and dosing device (controlling pH and conductivity)
There is a limit to the absorption of odor by circulating spray water. When the concentration of pollutants in the water is too high, it will have a significant impact on the deodorization effect. In order to increase the deodorization effect and improve the automation level of the equipment, it is recommended to add water quality monitoring devices and dosing adjustment devices when selecting equipment. Generally, equipment only needs to monitor the pH value and conductivity of the spray liquid to achieve this.