June 10, 2010
Compared with traditional commercial air source heat pump projects, hot water in slaughterhouses has higher requirements, and the design and construction of the system is more difficult.
1. Since the air source heat pump project in slaughterhouses is a high-temperature hot water project, great attention should be paid to the selection of pipe materials and insulation materials. common PPR pipes cannot be used for pipes. It is recommended to use galvanized pipes instead. Because PPR pipes are prone to deformation during long-term contact with high-temperature water, and may even cause bursting in severe cases.
2. In terms of pipe insulation materials, do not choose common rubber and plastic materials, especially the insulation of steam engine pipes. Rubber and plastic insulation materials will soften due to high temperature, thus deforming and affecting the insulation effect. It should be changed to asbestos material, and the thickness should not be less than 25 cm.
3. When choosing an insulated water tank, it is recommended to communicate more with the user. If you can choose 8 cm, don't choose 5 cm. Under normal circumstances, the difference between the two is only about 100 yuan/ton. If calculated according to the 6-ton project, the cost is only about 600 yuan, but the insulation effect is very obvious, especially in the north.
4. When designing the water consumption of the system, the correct water consumption design should be: total water consumption = soup pool capacity + miscellaneous parts cleaning consumption. If the water consumption is simply designed according to the soup pool capacity, there will be a problem of insufficient hot water supply. Generally, when slaughterhouses scald pigs, the hot water demand for washing miscellaneous parts of each pig is calculated to be about 15-20 liters.
5. The water in the soup pool needs to be designed with a constant temperature. During the process of scalding pigs, the water in the soup pool will cool down by about 5°C each time it is used, so a steam generator must be installed. Since slaughterhouses are generally located in the suburbs and gas pipelines are difficult to cover, it is recommended to use an electric steam generator or a biomass steam generator. If an electric steam generator is used, according to the average winter temperature of about 0°C, the soup pool capacity is within 4 tons, and the power selection of a 48kW air source heat pump can meet the demand.
If it is 6 tons or more than 8 tons, it needs to be recalculated. It is important to note that although the capacity of the 2-ton and 4-ton hot spring pools is half the size on the surface, when choosing an electric steam generator for a 2-ton hot spring pool, a 48kW air source heat pump should also be used. The reason is that the larger the capacity of the pool, the slower the water temperature drops during the scalding process.
6. For slaughtering less than 500 heads per day, it is not recommended to use a waste heat recovery system. Although a large amount of hot water is consumed every day in the slaughterhouse hot water project, the addition of waste heat recovery equipment also requires a certain amount of investment. For projects with a small slaughter volume, the cost may not be recovered in 5 years.
7. Generally speaking, slaughterhouses are far away from cities, so most of the water used comes from groundwater from self-built wells, especially in North China. Groundwater is very easy to scale after heating, so when doing slaughterhouse projects, be sure to use a TDS pen to test the water quality used. If the TDS test value exceeds 50, a descaling device must be installed separately.
8. For the rebuilt slaughterhouse air source heat pump project, if the project uses an electric steam generator, the total transformer capacity of the slaughterhouse and the load of the main power supply line and distribution box must also be considered. Once the project is signed, if the original distribution box or main power supply line is underloaded and the power supply system needs to be rebuilt, it will cause a great loss to oneself.
Air source heat pumps not only perfectly solve the heating needs of animal husbandry, but also greatly improve the economic benefits of farmers. With the expansion of scale, farmers' requirements for heating are not only sufficient heating capacity, but also require the ability to improve the economic benefits of breeding, which requires the heating system to achieve precise temperature control.
