Direct and reverse cycle coupling based absorption and compression combined type refrigerating system and method

Abstract

The invention discloses a direct and reverse cycle coupling based absorption and compression combined type refrigerating system and method. The system comprises a power subcycle and an absorption and compression combined type refrigerating subcycle. According to the direct and reverse cycle coupling based absorption and compression combined type refrigerating system and method, higher temperature portions of a medium and low temperature heat source drive the power subcycle to do work and accordingly the heat transfer temperature difference due to the fact that a heat source is directly applied to the absorption and compression combined type refrigerating system is reduced; lower temperature portions and the power subcycle are served as the heat source of the absorption and compression combined type refrigerating subcycle; work form the power subcycle drives a compressor in the absorption and compression combined type refrigerating subcycle; in the absorption and compression combined type refrigerating subcycle, the compressor is arranged between an evaporator and an absorber and the evaporation pressure can be lower than the absorption pressure, and accordingly the evaporation temperature can achieve a lower value, requirements in the low temperature refrigerating field are satisfied, and meanwhile the system can normally operate under the condition with the higher condensing temperature; the input energy of the integral system is the medium and low temperature heat source, the product output is low temperature capacity, and exterior input work is not required.

Description

technical field [0001] The invention relates to the technical field of medium and low temperature heat source refrigeration, in particular to an absorption-compression composite refrigeration system and method based on forward and reverse cycle coupling. Background technique [0002] Absorption refrigeration technology is a refrigeration technology that can be driven by low-temperature waste heat resources or low-temperature renewable energy such as solar energy and geothermal energy. It has a wide range of refrigeration temperatures, about -60°C to 10°C, and is widely used in air conditioning, cold storage, and petroleum smelting and other chemical processes. The evaporation temperature of conventional single-stage absorption refrigeration cannot be too low, and it is only suitable for some industrial sectors such as air conditioning and cold storage. But there are also some industrial sectors, such as the food processing industry (quick-freezing, freeze-drying, long-term ...

AI Technical Summary

Problems solved by technology

The evaporation temperature of conventional single-stage absorption refrigeration cannot be too low, and it is only suitable for some industrial sectors such as air conditioning and cold storage

But there are also some industrial sectors, such as the food processing industry (quick-freezing, freeze-drying, long-term preservation of food, etc.), some gas (propane, etc.) liquefaction, some low-temperature environmental laboratories, and solid CO 2 (Dry ice) production, etc., need to use low-temperature cooling capacity (such as lower than -30°C), at this time, single-stage absorption refrigeration is difficult to meet the requirements, and multi-stage processes are required

Although the two-stage absorption refrigeration cycle proposed by Rogdakis and Antonopoulos can produce cooling capacity from -70°C to -30°C, the thermal performance coefficient is low

In addition, when medium and low temperature heat energy (such as flue gas at 350°C) is used to directly drive the absorption refrigeration cycle, there will be a large temperature difference between the heat source and the working medium, resulting in large irreversible losses.

For the low-temperature cooling capacity, it can also be obtained by cascade compression refrigeration cycle in industry, but both the high-temperature zone and the low-temperature zone of the cycle use compression refrigeration cycle, which will consume a lot of work.

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