Precooling heat exchange system for oxygen generator

Abstract

The present invention relates to a precooling heat exchange system for an oxygen generator, comprising an outdoor circulation system which performs cooling heat exchange and then performs circulation to an indoor heat exchange system for heat exchange; and further comprising a control system. An control output end of the control system is connected to the outdoor circulation system. A signal input end of the control system is connected to the indoor circulation system. The indoor circulation system comprises a shell-and-tube heat exchanger, a water-cooled water chilling unit, and an indoor circulation pump, and primary industrial water is cooled by means of the shell-and-tube heat exchanger. The outdoor circulation system comprises an outdoor plate heat exchanger, a closed cooling tower, and an outdoor circulation pump. When an outdoor ambient temperature is lower than -2°C, the temperature formed by the shell-and-tube heat exchanger of the indoor circulation system is lowered by means of natural low-temperature heat exchange of the outdoor plate heat exchanger, and a shell-side heat exchange medium in the shell-and-tube heat exchanger is cooled in the outdoor closed cooling tower. The present invention greatly reduces power consumption, and finally achieves high-efficiency heat exchange and energy saving operation of the precooling system.

Description

Oxygen generator pre-cooling heat exchange system TECHNICAL FIELD

[0001] The present application relates to oxygen production technology field, especially to an oxygen generator pre-cooling heat exchange system. BACKGROUND

[0002] The 35000m 3 / h oxygen generator pre-cooling system process core is to cool the 100℃ high-temperature compressed air of the last stage of the air compressor to below 18℃ by 7℃-15℃ ultra-low temperature cooling water, and then enter the molecular sieve system for purification, and finally enter the air separation device for rectification to extract qualified oxygen, nitrogen and argon products.

[0003] The 7℃-15℃ ultra-low temperature cooling water of the oxygen pre-cooling process system is obtained by secondary cooling of 24℃-33℃ industrial circulating water. The secondary cooling of the industrial water is performed by three water chillers as a cold source, of which two have a refrigerating capacity of 1200kw and one has a refrigerating capacity of 1500kw. The water chillers consume a large amount of electricity during operation, and the production cost is high. Even in winter, the cooling water is cooled by the water chillers, and the low temperature weather in the northeast region is not effectively utilized to reduce the temperature of the pre-cooling process water by natural low temperature heat exchange. SUMMARY

[0004] The present application provides an oxygen generator pre-cooling heat exchange system. By the outdoor circulation system, indoor circulation system and control system of the system, the cold source is stabilized and the industrial refrigerators are stopped at the same time, the power consumption is greatly reduced, and finally the pre-cooling system realizes efficient heat exchange and energy-saving operation.

[0005] In order to achieve the above purpose, the present application adopts the following technical scheme:

[0006] An oxygen generator pre-cooling heat exchange system, comprising an outdoor circulation system and an indoor circulation system, the indoor circulation system comprising an indoor heat exchanger, a water-cooled chiller and an indoor circulating pump, the outdoor circulation system being circulated to the indoor heat exchange system after heat exchange and cooling, the water-cooled chiller of the indoor circulation system circulating the refrigerated circulating water into the heat exchanger for heat exchange, and then pumping out the heat exchange water by the indoor circulating pump; further comprising a control system, the control output end of the control system being connected to the outdoor circulation system, the signal input end of the control system being connected to the indoor circulation system, and the indoor heat exchanger being a column tube heat exchanger;

[0007] The outdoor circulating system comprises an outdoor plate heat exchanger, a closed cooling tower and an outdoor circulating pump, when the outdoor environment temperature is lower than -2 DEG C, the temperature formed by the tube heat exchanger of the indoor circulating system is reduced by natural low-temperature heat exchange of the outdoor plate heat exchanger, the shell side heat exchange medium of the tube heat exchanger is cooled in the closed cooling tower, and the outdoor circulating pump provides circulating power for the outdoor plate heat exchanger.

[0008] Further, the tube side of the tube heat exchanger of the indoor circulating system is primary industrial water, and the shell side is heat exchange medium glycol.

[0009] Further, the parameter of the indoor circulating pump is 115-120 m3 / h, and the outlet pressure is 10-15 Bar.

[0010] Further, the circulating medium of the outdoor plate heat exchanger of the outdoor circulating system is glycol antifreeze.

[0011] Further, the power of the outdoor circulating pump is 15 KW, and the flow is 110-160 m3 / h.

[0012] Further, the system further comprises fans, the number of the fans is 18-20, and the fans are arranged on the top of the outdoor plate heat exchanger.

[0013] Further, the final heat exchange temperature of the outdoor plate heat exchanger is controlled to be 5-8 DEG C.

[0014] Compared with the prior art, the present application has the following beneficial effects:

[0015] 1) Through the outdoor circulating system, the indoor circulating system and the control system of the system, the cold source is stabilized, the industrial refrigeration machine is stopped, the power consumption is greatly reduced, and finally the high-efficiency heat exchange energy-saving operation of the pre-cooling system is realized;

[0016] 2) Energy-saving operation in winter is realized, the power consumption of the original system is 247 kw / h, the power consumption is 497,900 yuan, and after the system is changed, the power consumption in winter is 907,000 yuan, and the total energy-saving benefit in winter is 407,200 yuan;

[0017] 3) The low-carbon and green development of oxygen production is substantially contributed, and the carbon emission is reduced by more than 700 tons;

[0018] 4) The new and old systems are automatically switched according to the air temperature conditions, the high-energy-consumption refrigeration machine is accurately controlled, and the energy consumption is flexibly reduced;

[0019] 5) The industrial refrigerant condenser operation industrial water consumption is reduced, the pre-cooling system industrial water demand is reduced, and the production line load is reduced. DETAILED DESCRIPTION

[0020] Figure 1 is a structural schematic diagram of the present application.

[0021] Figure 2 is a natural heat exchange and large refrigeration machine switching structure block diagram of the present application. DETAILED DESCRIPTION

[0022] The specific embodiments of the present application are further described below in conjunction with the accompanying drawings:

[0023] See Figure 1, which is a structural schematic diagram of the present application. The present application is an oxygen generator pre-cooling heat exchange system, which includes an outdoor circulation system, an indoor circulation system, a fan and a control system. The outdoor circulation system circulates after cooling and heat exchange to the indoor heat exchange system for heat exchange. The control output end of the control system is connected to the outdoor circulation system. The signal input end of the control system is connected to the indoor circulation system. The indoor circulation system includes an indoor heat exchanger, a water-cooled chiller and an indoor circulating pump. The indoor heat exchanger uses a shell-and-tube heat exchanger. The water-cooled chiller of the indoor circulation system flows the refrigerated circulating water into the heat exchanger for heat exchange, and then the indoor circulating pump pumps out the heat exchange water. The shell-and-tube heat exchanger cools the primary industrial water. The indoor circulating pump provides circulating power for the circulating medium in the shell-and-tube heat exchanger. The tube side of the shell-and-tube heat exchanger of the indoor circulation system is primary industrial water, and the shell side is heat exchange medium ethylene glycol. The outdoor circulation system includes an outdoor plate heat exchanger, a closed cooling tower and an outdoor circulating pump. When the outdoor environment temperature is lower than -2℃, the temperature formed by the shell-and-tube heat exchanger of the indoor circulation system is cooled by natural low-temperature heat exchange through the outdoor plate heat exchanger. Natural heat exchange replaces large refrigeration machines to achieve significant energy saving. The closed cooling tower in the outdoor environment cools the shell side heat exchange medium of the shell-and-tube heat exchanger. The outdoor circulating pump provides circulating power for the outdoor plate heat exchanger. The outdoor circulating pump provides circulating power for the outdoor plate heat exchanger. The outdoor plate heat exchanger of the outdoor circulation system circulates ethylene glycol antifreeze. The number of fans is 20, which are arranged at the top of the outdoor plate heat exchanger. The fan power is 1.5KW to achieve efficient heat exchange of the outdoor plate heat exchanger.

[0024] In the compressed air cooling process stage of the oxygen generator, the high-temperature compressed air discharged by the air compressor is cooled by chilled water. The preparation of chilled water is completed by 2-3 industrial refrigeration machines. The oxygen generator pre-cooling heat exchange system of the present application replaces the heat exchange circulation system of the existing industrial refrigeration machine. The indoor circulating water pump is set to have a flow rate of 118m3 / h and an outlet pressure of 10Bar. The outdoor circulating pump is a low-power high-efficiency circulating pump with a power of 15KW to ensure a flow rate of 160m3 / h. The outdoor heat exchange area is about 100m 2The outdoor circulation system will complete the temperature saturation of the ethylene glycol coolant formed by the indoor tube heat exchanger through the natural low-temperature heat exchange of the outdoor plate heat exchanger to realize cooling, and the cooled ethylene glycol is recycled to the indoor heat exchanger to exchange heat with industrial water, and the ethylene glycol coolant is driven by the outdoor circulation pump to circulate to the outdoor plate heat exchanger after being exchanged by the indoor tube heat exchanger, to form an automatic circulation cooling of the coolant.

[0025] As shown in FIG. 2, when the outdoor environment temperature is lower than -2℃, the temperature of the indoor circulation system formed by the tube heat exchanger is cooled through the natural low-temperature heat exchange of the outdoor plate heat exchanger, and the natural heat exchange is completed to replace the large refrigeration machine, and the closed cooling tower is outdoors, and the circulation of the closed cooling tower and the outdoor circulation pump is to lead the ethylene glycol coolant in the outdoor plate heat exchanger to the outdoor closed cooling tower, so that the ethylene glycol is cooled in the outdoor closed cooling tower, and the heat exchange capacity between the ethylene glycol and the industrial water entering the outdoor plate heat exchanger from the indoor circulation system is restored.

[0026] The outdoor plate heat exchanger is the intersection of the ethylene glycol coolant of the outdoor circulation system and the industrial water of the indoor circulation system, and the heat exchange is completed, so that the heat exchange between the water-cooled chiller and the industrial water is replaced.

[0027] The indoor circulation pump circulates the industrial water to the outdoor plate heat exchanger, and the ethylene glycol coolant entering the outdoor plate heat exchanger from the outdoor circulation system is exchanged, and then enters the next process flow for use.

[0028] The control system adjusts the ethylene glycol coolant at the outdoor temperature of 0℃ to -30℃, so that the final heat exchange temperature of the outdoor plate heat exchanger side is controlled to 5-8℃, which is the best heat exchange temperature of the compressed air at the front end of the molecular sieve process flow, and the process temperature is accurately controlled.

[0029] The pre-cooling system circulates water and low-temperature ethylene glycol to exchange heat through the heat exchanger, the ethylene glycol is exchanged at a temperature of 5-8℃, and the circulating water is exchanged at a temperature of 7-15℃, and the low-temperature circulating water enters the nitrogen cooling tower to complete the heat exchange purpose required by the present application.

[0030] The ethylene glycol exchanged with the system circulating water in the heat exchanger is raised in temperature, and is driven by the low-power outdoor circulation pump to circulate to the outdoor plate heat exchanger through the pipeline, the outdoor plate heat exchanger is provided with a low-power fan to realize forced air supply of low-temperature air, the ethylene glycol coolant is naturally exchanged with outdoor low-temperature air in the outdoor plate heat exchanger, and the heat exchange temperature is automatically and effectively controlled by the control system to be maintained at 5-8℃, and the ethylene glycol coolant is driven by the indoor circulation pump to enter the indoor tube heat exchanger again to form a cycle.

[0031] The above examples are implemented on the premise of the technical solution of the present application, and detailed implementation modes and specific operation processes are given, but the protection scope of the present application is not limited to the above examples. The methods used in the above examples are all conventional methods unless otherwise specified.

Claims

1. An oxygen generator pre-cooling heat exchange system, comprising an outdoor circulation system and an indoor circulation system, the indoor circulation system comprising an indoor heat exchanger, a water-cooled chiller and an indoor circulation pump, the outdoor circulation system circulating to the indoor heat exchange system after cooling heat exchange, the water-cooled chiller of the indoor circulation system circulating the chilled water to the heat exchanger for heat exchange, and then the indoor circulation pump pumping the heat exchanged water; characterized in that, Also include a control system, the control output of the control system is connected to the outdoor circulation system, the signal input of the control system is connected to the indoor circulation system, the indoor heat exchanger uses column tube heat exchanger; The outdoor circulation system includes outdoor plate heat exchanger, closed cooling tower, outdoor circulating pump, when the outdoor environment temperature is lower than -2℃, the temperature formed by the column tube heat exchanger of the indoor circulation system is cooled by the natural low temperature heat exchange of the outdoor plate heat exchanger, the shell side heat exchange medium of the column tube heat exchanger is cooled in the outdoor closed cooling tower, and the outdoor circulating pump provides circulating power for the outdoor plate heat exchanger.

2. The pre-cooling heat exchange system of an oxygen generator according to claim 1, characterized in that, The tube side of the column tube heat exchanger of the indoor circulation system is primary industrial water, and the shell side is heat exchange medium glycol.

3. The pre-cooling heat exchange system of an oxygen generator according to claim 1, characterized in that, The indoor circulating water pump parameters are flow 115-120 m 3 / h, outlet pressure 10-15 Bar.

4. The pre-cooling heat exchange system of an oxygen generator according to claim 1, characterized in that, The circulating medium of the outdoor plate heat exchanger of the outdoor circulation system is glycol antifreeze solution.

5. The pre-cooling heat exchange system of an oxygen generator according to claim 1, characterized in that, The outdoor circulating pump power is 15KW, ensuring the flow rate of 110-160m 3 / h.

6. The pre-cooling heat exchange system of an oxygen generator according to claim 1, characterized in that, Also include a fan, the number of fans is 18-20, and the fan is arranged on the top of the outdoor plate heat exchanger.

7. The pre-cooling heat exchange system of an oxygen generator according to claim 1, characterized in that, The final heat exchange temperature of the outdoor plate heat exchanger is controlled to be 5-8℃.

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