Efficient ammonia compressor starting device

Abstract

The utility model relates to the technical field of ammonia compressor start-up, in particular to an efficient ammonia compressor start-up device which comprises an ammonia compressor and a gas ammonia pipeline used for leading in gas ammonia, an inlet of the ammonia compressor is connected with one port of the gas ammonia pipeline, the gas ammonia pipeline is communicated with an inlet of a start-up ejector, and the start-up ejector is communicated with an outlet of the ammonia compressor. An outlet of the starting ejector is connected with an inlet of the liquid separation tank, an outlet of the ammonia compressor is connected with an inlet of the cooler, an outlet of the cooler is connected with an inlet of the first condenser, and the outlet of the cooler is further connected with an inlet of the second condenser. According to the utility model, the starting ejector is utilized to perform negative pressure pumping on the gas ammonia pipeline, so that the kinetic energy is improved, the efficiency of replacing nitrogen with ammonia gas is accelerated, the starting time is shortened, the starting cost of a chemical device is reduced, and the consumption of ammonia is reduced. The cooled liquid ammonia is conveyed to a required position through a liquid ammonia conveying pipeline; and the gas ammonia is conveyed to the gas ammonia pipeline for reutilization.

Description

Technical Field

[0001] The utility model relates to the technical field of starting an ammonia compressor, and particularly relates to an efficient device for starting an ammonia compressor. Background Art

[0002] Ammonia compression refrigeration is a large-scale machinery widely used in chemical projects. To prevent explosion caused by the contact of ammonia with air and poisoning caused by ammonia leakage, there is 99.9% nitrogen in the ammonia refrigeration system. When starting an ammonia compressor initially or restarting it after maintenance, the ammonia compressor needs to use ammonia to displace the nitrogen in the system. However, the molecular weight and density of nitrogen are much larger than those of ammonia (ammonia density is 0.77 and molecular weight is 17, nitrogen density is 1.25 and molecular weight is 28), and the following problems occur: 1. The time for ammonia to displace nitrogen is long, which prolongs the starting time and increases the starting cost of the chemical device system; 2. The displacement of nitrogen by ammonia is not complete, and more nitrogen in the system leads to surging of the ammonia compressor; 3. When the ammonia compressor is not normal (when surging occurs), the inlet cannot reach negative pressure, the gas fluidity is small, and the time is long while the consumption of ammonia is also increased, wasting materials. Content of the Utility Model

[0003] The purpose of the utility model is to provide an efficient device for starting an ammonia compressor.

[0004] The utility model provides the following technical solution:

[0005] The utility model provides an efficient device for starting an ammonia compressor, which includes an ammonia compressor and an ammonia gas pipeline for introducing gaseous ammonia. The inlet of the ammonia compressor is connected to one end port of the ammonia gas pipeline. The inlet of a starting ejector is communicated with the ammonia gas pipeline. The outlet of the starting ejector is connected to the inlet of a liquid separation tank. The outlet of the ammonia compressor is connected to the inlet of a cooler. The outlet of the cooler is connected to the inlet of a first condenser and is also connected to the inlet of a second condenser.

[0006] Furthermore, it further includes a liquid ammonia buffer tank. The liquid discharge outlets of the first condenser and the second condenser are both connected to the liquid inlet of the liquid ammonia buffer tank. The gas discharge outlets of the first condenser and the second condenser are both connected to the gas inlet of the liquid ammonia buffer tank. The liquid discharge outlet of the liquid ammonia buffer tank is connected to a liquid ammonia conveying pipeline.

[0007] Furthermore, a non-condensable gas separator is arranged in the liquid ammonia buffer tank, and the gas discharge outlet of the non-condensable gas separator is connected to the ammonia gas pipeline.

[0008] Furthermore, a first pump is arranged on the connecting pipeline between the ammonia gas pipeline and the inlet of the starting ejector.

[0009] Further, the steam inlet of the start-up ejector is connected to one end of a steam pipeline, and a second pump is provided on the steam pipeline.

[0010] Further, a third pump is provided on the gaseous ammonia pipeline.

[0011] Compared with the prior art, the utility model provides an efficient ammonia compressor starting device with a simple structure. The start-up ejector is used to extract negative pressure from the gaseous ammonia pipeline, enhance the kinetic energy, accelerate the efficiency of ammonia replacing nitrogen, shorten the starting time, and reduce the starting cost of the chemical plant. During the replacement period, the ammonia compressor does not need to be started, which avoids the surge caused by nitrogen entering the compressor, reduces the consumption of motive steam while avoiding equipment damage, and reduces the consumption of ammonia. The liquid ammonia obtained through cooling is transported to the required position through the liquid ammonia transportation pipeline; the gaseous ammonia is recovered and sent to the gaseous ammonia pipeline for reuse. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a connection schematic diagram of the utility model.

[0013] (The arrows in the figure indicate the direction of material flow)

[0014] In the figure, 1 - ammonia compressor; 2 - gaseous ammonia pipeline; 3 - start-up ejector; 4 - liquid separation tank; 5 - cooler; 6 - first condenser; 7 - second condenser; 8 - liquid ammonia buffer tank; 9 - liquid ammonia transportation pipeline; 10 - non-condensable gas separator; 11 - first pump; 12 - second pump; 13 - third pump; 14 - steam pipeline. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] The following further describes the utility model Figure 1 in conjunction with the attached drawings.

[0016] In the following embodiments, the start-up ejector adopts a steam ejector, the cooler adopts a shell-and-tube heat exchanger, the first condenser adopts a tank-type separator, and the second condenser adopts a tank-type separator.

[0017] In an embodiment of the present utility model, an efficient ammonia compressor starting device includes an ammonia compressor 1 and an ammonia gas pipeline 2 for introducing gaseous ammonia. The inlet of the ammonia compressor 1 is connected to one end of the ammonia gas pipeline 2. The inlet of a starting ejector 3 is communicated with the ammonia gas pipeline 2. The outlet of the starting ejector 3 is connected to the inlet of a liquid separation tank 4. The outlet of the ammonia compressor 1 is connected to the inlet of a cooler 5. The outlet of the cooler 5 is connected to the inlet of a first condenser 6 and is also connected to the inlet of a second condenser 7. In practical applications, steam and nitrogen are mixed and enter the liquid separation tank 4 from the starting ejector 3. The volume continues to expand and the pressure continues to decrease. The steam condenses into water, and the volume becomes smaller to form a negative pressure area, thereby increasing the suction force and continuously pumping air to achieve negative pressure pumping on the ammonia gas pipeline 2, enhancing the kinetic energy, accelerating the efficiency of ammonia replacing nitrogen, shortening the starting time, and reducing the starting cost of the chemical device. During the replacement period, the ammonia compressor does not need to be started, avoiding nitrogen entering the compressor to cause surging, reducing the consumption of power steam while avoiding equipment damage and reducing the consumption of ammonia. The liquid ammonia obtained from the first condenser and the second condenser is sent to the required location, and the liquid ammonia evaporates, absorbing heat from the outside to achieve refrigeration.

[0018] In an embodiment of the present utility model, it further includes a liquid ammonia buffer tank 8. The liquid discharge outlets of the first condenser 6 and the second condenser 7 are both connected to the liquid inlet of the liquid ammonia buffer tank 8. The gas discharge outlets of the first condenser 6 and the second condenser 7 are both connected to the gas inlet of the liquid ammonia buffer tank 8. The liquid discharge outlet of the liquid ammonia buffer tank 8 is connected to a liquid ammonia conveying pipeline 9. It is stored in the liquid ammonia buffer tank and the liquid ammonia in the liquid ammonia buffer tank 8 is sent out through the liquid ammonia conveying pipeline 9.

[0019] In an embodiment of the present utility model, a non-condensable gas separator 10 is arranged in the liquid ammonia buffer tank 8. The gas discharge outlet of the non-condensable gas separator 10 is connected to the ammonia gas pipeline 2. The gas-liquid is further separated by the non-condensable gas separator, and the gaseous ammonia is sent to the ammonia gas pipeline 2 through the gas discharge outlet of the non-condensable gas separator 10 for reuse.

[0020] In an embodiment of the present utility model, a first pump 11 is arranged on the connecting pipeline between the ammonia gas pipeline 2 and the inlet of the starting ejector 3; it is convenient to control the flow rate.

[0021] In an embodiment of the present utility model, the steam inlet of the starting ejector 3 is connected to one end of a steam pipeline 14. A second pump 12 is arranged on the steam pipeline 14; it is convenient to control the flow rate.

[0022] In an embodiment of the present utility model, a third pump 13 is arranged on the ammonia gas pipeline 2; it is convenient to control the flow rate.

[0023] In practical applications, steam and nitrogen are mixed and enter the liquid separation tank 4 from the start-up ejector 3. The volume continues to expand and the pressure continues to decrease. The steam condenses into water, and the volume becomes smaller to form a negative pressure area, thereby increasing the suction force and continuously pumping air to achieve a negative pressure on the gas ammonia pipeline 2, enhancing the kinetic energy, accelerating the efficiency of ammonia replacing nitrogen, shortening the start-up time, and reducing the start-up cost of the chemical plant; during the replacement period, the ammonia compressor does not need to be started, avoiding the surge caused by nitrogen entering the compressor, reducing the consumption of power steam while avoiding equipment damage, and reducing the consumption of ammonia; the liquid ammonia buffer tank is used for storage, and the liquid ammonia in the liquid ammonia buffer tank 8 is sent out through the liquid ammonia delivery pipeline 9; the gas-liquid is further separated through the non-condensable gas separator, and the gas ammonia is sent to the gas ammonia pipeline 2 through the gas discharge port of the non-condensable gas separator 10 for reuse.

[0024] The embodiments of the present invention are given for the purposes of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A high-efficiency ammonia compressor start-up device, characterized in that: It includes an ammonia compressor and an ammonia pipeline for introducing ammonia gas, wherein the inlet of the ammonia compressor is connected to one end of the ammonia pipeline, the ammonia pipeline is connected to the inlet of a start-up ejector, the outlet of the start-up ejector is connected to the inlet of a liquid separator, the outlet of the ammonia compressor is connected to the inlet of a cooler, the outlet of the cooler is connected to the inlet of a first condenser, and the outlet of the cooler is also connected to the inlet of a second condenser.

2. The high-efficiency ammonia compressor start-up device according to claim 1 is characterized in that: It also includes a liquid ammonia buffer tank, wherein the liquid discharge port of the first condenser and the liquid discharge port of the second condenser are both connected to the liquid inlet of the liquid ammonia buffer tank, the gas discharge port of the first condenser and the gas discharge port of the second condenser are both connected to the gas inlet of the liquid ammonia buffer tank, and the liquid discharge port of the liquid ammonia buffer tank is connected to a liquid ammonia delivery pipeline.

3. The high-efficiency ammonia compressor start-up device according to claim 2 is characterized in that: A non-condensable gas separator is arranged in the liquid ammonia buffer tank, and a gas outlet of the non-condensable gas separator is connected to the gas ammonia pipeline.

4. The high-efficiency ammonia compressor start-up device according to claim 1 is characterized in that: A first pump is provided on the connecting pipeline between the gas ammonia pipeline and the inlet of the start-up ejector.

5. The high-efficiency ammonia compressor start-up device according to claim 1 is characterized in that: The steam inlet of the start-up ejector is connected to a port of a steam pipeline, and a second pump is arranged on the steam pipeline.

6. The high-efficiency ammonia compressor start-up device according to claim 1, characterized in that: The gas ammonia pipeline is provided with a third pump.

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