CN-122015352-A - Refrigerant circulating device for large-scale low-temperature evaporation equipment and operation method

CN122015352ACN 122015352 ACN122015352 ACN 122015352ACN-122015352-A

Abstract

The invention provides a refrigerant circulation device and an operation method for large-scale low-temperature evaporation equipment, which can solve the problems that a single compressor directly causes the shutdown of a whole machine and the uneven distribution of refrigerants among compressors, realize the continuous and stable operation of the large-scale low-temperature evaporation equipment, and comprise a condenser and also comprise independent refrigerant circulation units connected with the condenser, wherein at least two independent refrigerant circulation units are arranged, each independent refrigerant circulation unit respectively forms a mutually independent refrigerant circulation loop, the independent refrigerant circulation units respectively comprise compressors connected through pipelines, the exhaust ports of the compressors are communicated with the inlet ends of the condenser, the liquid outlet ends of the condensers are connected with the inlet ends of the evaporators through refrigerant on-off control valves and electronic expansion valves, and the refrigerant on-off control valves are used for controlling the on-off of the pipelines, and the outlet of the evaporators is connected with the air return ports of the compressors.

Inventors

LIU CHENXI
CHEN GUANGMING
Liang Rongxian
Shen Shuhuan

Assignees

江苏威胜达资源循环科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260331

Claims (10)

1. The refrigerant circulation device for the large-scale low-temperature evaporation equipment comprises a condenser, and is characterized by further comprising independent refrigerant circulation units connected with the condenser, wherein at least two independent refrigerant circulation units are arranged, each independent refrigerant circulation unit respectively forms a mutually independent refrigerant circulation loop, and each independent refrigerant circulation unit respectively comprises a refrigerant circulation loop connected through a pipeline: The air outlet of the compressor is communicated with the air inlet end of the condenser, the liquid outlet end of the condenser is connected with the inlet of the evaporator through a refrigerant on-off control valve and the electronic expansion valve, the refrigerant on-off control valve is used for controlling on-off of a pipeline, and the outlet of the evaporator is connected with the air return port of the compressor.
2. The refrigerant circulating device for a large-scale low-temperature evaporation device according to claim 1, wherein the independent refrigerant circulating units further comprise oil separators, the exhaust ports of the compressors are connected with the air inlet ends of the condensers through the oil separators, the oil separators can separate oil and gas of exhaust gases of the compressors, and lubricating oil separated by the oil separators returns to the compressors through oil return pipelines.
3. The refrigerant circulating device for a large-scale low-temperature evaporation apparatus as claimed in claim 2, wherein the independent refrigerant circulating units further comprise gas-liquid separators, respectively, and the outlets of the evaporators are connected with the air return port of the compressor through the gas-liquid separators, and are used for performing gas-liquid separation on the refrigerant flowing out of the evaporators.
4. A refrigerant circulation device for a large-scale low-temperature evaporation apparatus as defined in claim 3, wherein the independent refrigerant circulation units further comprise a dry filter, the liquid outlet end of the condenser is connected with the refrigerant on-off control valve through the dry filter, the inlet of the dry filter is communicated with the refrigerant outlet of the condenser, the outlet of the dry filter is connected with the refrigerant on-off control valve, and the dry filter can adsorb moisture in the refrigerant and impurities in a filtering pipeline.
5. A refrigerant circulation device for a large-scale low-temperature evaporation apparatus as defined in claim 1, wherein said condenser is communicated with each of said independent refrigerant circulation units through an air inlet pipe and a liquid outlet pipe, respectively, which are independent of each other, and all of the independent refrigerant circulation units share the same condenser.
6. A refrigerant circulation device for a large-scale low-temperature evaporation apparatus according to claim 1, further comprising a control unit configured to control compressors in a plurality of said independent refrigerant circulation units to be sequentially started at intervals in a preheating stage of apparatus start-up, for preventing overload of the apparatus caused by superposition of start-up currents generated when a plurality of compressors are simultaneously started up.
7. The refrigerant circulation device for a large-scale low-temperature evaporation apparatus according to claim 6, wherein the control unit is configured to control the refrigerant on-off control valve of the corresponding failed independent refrigerant circulation unit to be closed when a failure is detected by the compressor of any one of the independent refrigerant circulation units, so that the corresponding failed independent refrigerant circulation unit is stopped, and the remaining normal independent refrigerant circulation units are maintained to continuously operate.
8. A refrigerant circulation device for a large-scale low-temperature evaporation apparatus as defined in claim 4, wherein the compressor, the dry filter, the refrigerant on-off control valve, the electronic expansion valve, the oil separator, the gas-liquid separator and the evaporator of the independent refrigerant circulation unit are arranged in layers along the vertical direction and connected through pipelines, and a plurality of independent refrigerant circulation units are arranged on one side of the condenser in parallel.
9. A large-scale low-temperature evaporation device is characterized by comprising the refrigerant circulation device for the large-scale low-temperature evaporation device according to any one of claims 1 to 8, wherein the total refrigeration requirement of the low-temperature evaporation device can be met by the superposition of the cold energy of each independent refrigerant circulation unit.
10. A method of operating a refrigerant circulation device for a large-sized low-temperature evaporation apparatus, applied to the refrigerant circulation device for a large-sized low-temperature evaporation apparatus according to any one of claims 1 to 8, characterized by comprising: in the preheating stage, sequentially starting compressors in each independent refrigerant circulation unit according to a set time interval; And when the abnormal operation of the single compressor or the corresponding refrigerant circulation branch is monitored, the refrigerant circulation units corresponding to the abnormal operation are stopped, and the rest normal refrigerant circulation units continue to operate.

Description

Refrigerant circulating device for large-scale low-temperature evaporation equipment and operation method Technical Field The invention relates to the technical field of heat exchange matched with low-temperature evaporation equipment, in particular to a refrigerant circulating device for large-scale low-temperature evaporation equipment and an operation method. Background The low-temperature evaporation equipment is widely applied to industries such as chemical industry, medicine, food and the like, low-temperature concentration, drying or distillation of materials is realized through evaporation refrigeration, the refrigeration capacity requirement of large-scale low-temperature evaporation equipment is large, and a single compressor is difficult to meet, so that a scheme of cooperative refrigeration by a plurality of compressors is generally adopted. In the prior art, a refrigeration system is usually formed by adopting a structure that a plurality of compressors are connected in parallel, refrigerant discharged by the compressors is mixed into a condenser to complete condensation after being connected in parallel through copper pipes, liquid refrigerant is distributed to an evaporator through a shared pipeline, and after evaporation refrigeration is completed, gaseous refrigerant is redistributed back to each compressor to be compressed, so that circulating refrigeration is realized. In the parallel connection structure of a plurality of compressors, each compressor shares the same refrigerant pipeline system, when any single compressor has abnormal oil return, lubrication fault or other faults, the operation of the whole low-temperature evaporation equipment is usually required to be stopped to ensure the safety of the equipment, the production process is interrupted, the economic loss is large, in the parallel connection pipeline refrigerating system, the refrigerating pipelines are not mutually independent, the flowing resistance of each branch pipeline is different, the working states of the compressors are different in the operation process, the compressors are mutually interfered through the shared pipeline, even if a condenser with larger specification is configured, more refrigerant is filled, the refrigerant distribution in each compressor still has uneven phenomenon, and the refrigerating effect is reduced. Disclosure of Invention The invention provides a refrigerant circulation device and an operation method for large-scale low-temperature evaporation equipment, which can solve the problems that a single compressor directly causes the shutdown of a whole machine and the refrigerant distribution among compressors is uneven, and realize the continuous and stable operation of the large-scale low-temperature evaporation equipment. The refrigerant circulation device for the large-scale low-temperature evaporation equipment comprises a condenser and is characterized by further comprising independent refrigerant circulation units connected with the condenser, wherein at least two independent refrigerant circulation units are arranged, each independent refrigerant circulation unit respectively forms a mutually independent refrigerant circulation loop, and each independent refrigerant circulation unit respectively comprises a refrigerant circulation loop connected through a pipeline: the exhaust port of the compressor is communicated with the air inlet end of the condenser, the liquid outlet end of the condenser is connected with the inlet of the evaporator through a refrigerant on-off control valve and an electronic expansion valve, the refrigerant on-off control valve is used for controlling on-off of a pipeline, and the outlet of the evaporator is connected with the air return port of the compressor. The independent refrigerant circulation units further respectively comprise an oil separator, the exhaust port of the compressor is connected with the air inlet end of the condenser through the oil separator, the oil separator can separate oil from gas of the exhaust of the compressor, and lubricating oil separated by the oil separator returns to the compressor through an oil return pipeline. Further, the independent refrigerant circulation units further comprise gas-liquid separators respectively, and the outlets of the evaporators are connected with the air return ports of the compressors through the gas-liquid separators and are used for performing gas-liquid separation on the refrigerant flowing out of the evaporators. Further, the independent refrigerant circulation units further comprise a drying filter respectively, the liquid outlet end of the condenser is connected with the refrigerant on-off control valve through the drying filter, the inlet of the drying filter is communicated with the refrigerant outlet of the condenser, the outlet of the drying filter is connected with the refrigerant on-off control valve, and the drying filter can adsorb moisture in the refrigerant and impurities in the f