Direct heat pump integrated variable pressure drying system and method

Abstract

The invention discloses a direct heat pump integrated variable pressure drying system and method, and belongs to the fields of energy, power and the like. The system is characterized in that an evaporator of a conventional direct heat pump is used as a cold source, a condenser is a heat source, after the circulating air is pressurized and heated through the air compressor, the temperature is reduced and the humidity is increased after the circulating air exchanges heat and wet with wet materials in the drying box, and then the circulating air is divided into two paths: one path of circulatingair is mixed with high-temperature air at the inlet of the drying box through a circulating fan to reduce the heat damage of inlet materials; and the other path of circulating air is cooled through the evaporator, and then enters a gas-liquid separator through pressure reduction and condensation of an expansion machine, and after the gas absorbs heat in the condenser, the gas enters the air compressor to start the next round of circulation. According to the system, the compressor and the expansion machine are additionally arranged in the closed air circulation, and the pressure ratio of the air compressor and a refrigerant compressor can be adjusted, so that the requirements of different drying box temperatures and water condensation rates can be met. According to the system, closed circulation is adopted, and the influence of ambient air cleanliness, temperature and humidity is avoided; and meanwhile, due to the fact that part of the expansion work is recycled by the expansion machine, the system can be used for effectively saving energy and effectively dehumidifying.

Description

technical field [0001] The invention relates to a direct heat pump integrated pressure-variable drying system and method, belonging to the field of energy and power. Background technique [0002] In modern industry, for the use and further processing of materials, drying methods are usually adopted. Drying technology is not only widely used in food, chemical, pharmaceutical and other industries, but also plays an important role in emerging industries such as biotechnology and nanotechnology. Drying is currently a high-energy-consuming operation, accounting for a relatively high proportion of the total energy consumption of production. At the same time, different materials have different requirements on the properties after drying, different operating conditions are required in drying, and there are different requirements for drying methods and drying equipment. Therefore, it is necessary to design a drying system with high efficiency and energy saving, and a wide range of a...

AI Technical Summary

Problems solved by technology

The open heat pump drying device has a simple structure and is easy to operate, but it is greatly affected by the ambient temperature; the closed drying device can save the intake air purification equipment, has no exhaust pollution to the environment, the drying temperature can be adjusted, and there are many choices of drying media; The semi-open drying device is in between

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