Natural gas reciprocating compressor unit

Abstract

The embodiment of the invention discloses a natural gas reciprocating compressor unit, belongs to the technical field of compressors, and solves the problem that in the prior art, in order to meet different natural gas compression conditions, double-unit configuration is needed, so that the equipment cost is high. The unit comprises a first natural gas treatment device and a second natural gas treatment device which are used for compressing entering natural gas; the first valve is in an open state under a first condition, so that the entering natural gas is compressed in parallel through the first natural gas treatment device and the second natural gas treatment device; the second valve is in an open state under a second condition, so that the natural gas subjected to primary compression enters the second natural gas treatment device to be subjected to secondary compression; and the third valve is in an open state under the first condition, so that the natural gas subjected to parallel compression is mixed.

Description

Technical Field

[0001] The present application relates to the technical field of compressors, and in particular to a natural gas reciprocating compressor unit. Background Art

[0002] In the field of natural gas energy management and utilization, reciprocating compressors are widely used as key equipment in the natural gas extraction and transportation process. Their efficient and stable operation is crucial to ensuring the extraction, storage and seasonal allocation of natural gas.

[0003] In the prior art, the pressure difference between the inlet and outlet of the gas injection condition is relatively large, while the pressure difference between the inlet and outlet of the gas production condition is relatively small, and the number of compression stages of the gas injection condition is greater than that of the gas production condition. Therefore, in order to meet different natural gas processing needs, it is often necessary to configure two independent compressor units: one is dedicated to the summer gas injection period, responsible for injecting the collected natural gas into the gas storage reservoir for storage to meet future supply needs; and the other is focused on the winter gas production period, extracting natural gas from the gas storage reservoir to ensure the stability of heating and energy supply. However, although the operating mode in the prior art guarantees the continuity of production activities to a certain extent, in order to meet different natural gas compression conditions, it requires a dual-unit configuration, which not only increases the equipment investment cost, but also occupies valuable site area. Summary of the invention

[0004] The embodiment of the present application provides a natural gas reciprocating compressor unit for solving the following technical problems: In order to meet different natural gas compression conditions in the prior art, a dual unit configuration is required, which not only increases the equipment investment cost, but also occupies valuable site area.

[0005] The present application embodiment adopts the following technical solutions: The embodiment of the present application provides a natural gas reciprocating compressor unit. The unit includes: a first natural gas processing device and a second natural gas processing device, which are used to compress the incoming natural gas; a first valve, one end of which is connected to the air inlet end of the first natural gas processing device, and the other end is connected to the air inlet end of the second natural gas processing device. The first valve is in an open state under a first condition, so that the incoming natural gas is compressed in parallel through the first natural gas processing device and the second natural gas processing device, and the first valve is in a closed state under a second condition; a second valve, one end of which is connected to the air outlet end of the first natural gas processing device, and the other end is connected to the air inlet end of the second natural gas processing device. The second valve is in an open state under the second condition, so that the natural gas after the first stage of compression is compressed in parallel. The gas is fed into the second natural gas processing device for secondary compression; the second valve is in a closed state under the first condition; the third valve has one end connected to the gas outlet end of the first natural gas processing device and the other end connected to the gas outlet end of the second natural gas processing device, and the third valve is in an open state under the first condition to mix the natural gas compressed in parallel; the third valve is in a closed state under the second condition; wherein the first condition is the gas production stage, or the pressure difference between the gas inlet of the first natural gas processing device and the gas outlet of the second natural gas processing device is less than the first threshold value; the second condition is the gas injection stage, or the pressure difference between the gas inlet of the first natural gas processing device and the gas outlet of the second natural gas processing device is greater than the first threshold value.

[0006] The embodiment of the present application meets different demands for natural gas under different natural gas compression conditions through a set of units, avoids equipment idleness, and improves equipment utilization. The opening of the first valve and the third valve enables the first natural gas processing device and the second natural gas processing device to work in parallel and jointly process the incoming natural gas, thereby improving processing efficiency. By opening the second valve, the natural gas after the first-stage compression directly enters the second natural gas processing device for series compression, meeting the compression requirements under high pressure difference. Compared with the traditional dual-unit configuration, the embodiment of the present application only requires one set of compressor units and corresponding valve control systems, which significantly reduces the equipment investment cost and saves floor space.

[0007] In a feasible embodiment, the first natural gas processing device includes: a first-level air intake scrubber, the first-level air intake scrubber is used to filter the incoming natural gas; a first-level air intake buffer, the air inlet end of the first-level air intake buffer is connected to the air outlet end of the first-level air intake scrubber, and is used to buffer the natural gas filtered by the first-level air intake scrubber; a first-level compression cylinder, the air inlet end of the first-level compression cylinder is connected to the air outlet end of the first-level air intake buffer, and is used to compress the natural gas buffered by the first-level air intake buffer; a first-level exhaust buffer, the air inlet end of the first-level exhaust buffer is connected to the air outlet end of the first-level compression cylinder, and is used to buffer the natural gas compressed by the first-level compression cylinder; a first-level air cooler, the air inlet end of the first-level air cooler is connected to the air outlet end of the first-level exhaust buffer, and is used to cool the natural gas buffered by the first-level exhaust buffer.

[0008] In a feasible embodiment, the second natural gas processing device includes: a secondary air intake scrubber, the secondary air intake scrubber is used to filter the incoming natural gas; a secondary air intake buffer, the air inlet end of the secondary air intake buffer is connected to the air outlet end of the secondary air intake scrubber, and is used to buffer the natural gas filtered by the secondary air intake scrubber; a secondary compression cylinder, the air inlet end of the secondary compression cylinder is connected to the air outlet end of the secondary air intake buffer, and is used to compress the natural gas buffered by the secondary air intake buffer; a secondary exhaust buffer, the air inlet end of the secondary exhaust buffer is connected to the air outlet end of the secondary compression cylinder, and is used to buffer the natural gas compressed by the secondary compression cylinder; a secondary air cooler, the air inlet end of the secondary air cooler is connected to the air outlet end of the secondary exhaust buffer, and is used to cool the natural gas buffered by the secondary exhaust buffer.

[0009] In a feasible embodiment, the unit also includes a secondary exhaust separator connected to the gas outlet end of the second natural gas processing device, and also includes a secondary exhaust filter connected to the gas outlet end of the secondary exhaust separator; a bypass pipeline is provided between the gas outlet end of the secondary exhaust separator and the gas outlet end of the secondary exhaust filter, and the bypass pipeline is provided with a fourth valve; a vent pipeline is provided at the gas outlet end of the secondary exhaust filter, and the vent pipeline is provided with a fifth valve; a sixth valve is provided between the secondary exhaust separator and the secondary exhaust filter; and a seventh valve is provided between the secondary exhaust filter and the downstream.

[0010] In a feasible implementation, when the filter element of the secondary exhaust filter is replaced, the fourth valve is in an open state, and the sixth valve and the seventh valve are both in a closed state, so that the natural gas discharged from the secondary exhaust separator is transferred to the downstream through the bypass pipeline; the fifth valve is in an open state, so that the natural gas in the secondary exhaust filter is discharged through the vent pipeline; a nitrogen purge port is provided on the secondary exhaust filter, and the nitrogen purge port is used for nitrogen purge after the natural gas in the secondary exhaust filter is discharged, so as to replace the filter element online.

[0011] The embodiment of the present application realizes the online replacement of the exhaust filter element through nitrogen purging and valve control, without stopping the machine or interrupting the production process, which significantly improves the maintenance efficiency and production continuity. Secondly, frequent shutdowns not only affect production efficiency, but also increase energy waste and maintenance costs. The embodiment of the present application effectively reduces additional costs by reducing downtime.

[0012] In a feasible implementation, the unit is provided with a return pipeline, one end of the return pipeline is connected to the air inlet port of the unit, and the other end of the return pipeline is connected to the air outlet port of the unit; a pneumatic regulating valve and a pneumatic switching valve are arranged in parallel on the return pipeline, and when the unit is started, the pneumatic regulating valve and the pneumatic switching valve are in the open state at the same time.

[0013] In a feasible implementation manner, the gas inlet end of the first natural gas processing device of the unit, the first natural gas processing device and the second natural gas processing device are respectively provided with two-way safety valve groups.

[0014] In a feasible implementation, the two-way safety valve group includes a first safety valve group and a second safety valve group; under a first condition, the first safety valve group is in an open state and the second safety valve group is in a closed state; under a second condition, the first safety valve group is in a closed state and the second safety valve group is in an open state; wherein the safety value threshold corresponding to the first safety valve group is less than the safety value threshold corresponding to the second safety valve group.

[0015] The embodiment of the present application achieves double safety protection by setting up dedicated safety valve groups for different operation stages. At any stage, at least one group of safety valves is under monitoring and available, reducing the risk of safety accidents caused by a single failure. Secondly, the requirements for pressure control under different compression conditions are different. Setting up safety valve groups separately can be accurately adjusted according to actual working conditions, improving the flexibility and adaptability of operation.

[0016] In a feasible implementation manner, the scrubber in the unit is provided with a glass plate level gauge and a differential pressure transmitter, and the glass plate level gauge is used to calibrate the reading of the differential pressure transmitter.

[0017] In a feasible implementation manner, the unit is provided with an alarm device, and the alarm device corresponds to different alarm thresholds under the first condition and the second condition respectively.

[0018] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects: the embodiments of the present application meet different demands for natural gas under different natural gas compression conditions through a set of units, avoiding equipment idleness and improving equipment utilization. The opening of the first valve and the third valve enables the first natural gas processing device and the second natural gas processing device to work in parallel and jointly process the incoming natural gas, thereby improving processing efficiency. By opening the second valve, the natural gas after the first-stage compression directly enters the second natural gas processing device for series compression, meeting the compression requirements under high pressure difference. Compared with the traditional dual-unit configuration, the embodiments of the present application only require one set of compressor units and corresponding valve control systems, which significantly reduces the equipment investment cost and saves floor space. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. In the drawings: Figure 1 A schematic diagram of a natural gas reciprocating compressor unit provided in an embodiment of the present application; Figure 2 A flowchart of a natural gas reciprocating compressor unit operation under a first condition provided in an embodiment of the present application; Figure 3 A flowchart of the operation of a natural gas reciprocating compressor unit under a second condition provided in an embodiment of the present application; Figure 4 A structural diagram of a natural gas reciprocating compressor unit provided in an embodiment of the present application; Figure 5 A schematic diagram of a two-way safety valve group provided in an embodiment of the present application; Figure 6 A schematic diagram of a first natural gas processing device provided in an embodiment of the present application; Figure 7 A schematic diagram of a second natural gas processing device provided in an embodiment of the present application; Figure 8 A schematic diagram of a two-stage exhaust filter device provided in an embodiment of the present application. Description of the drawings: 110 natural gas reciprocating compressor unit, 111 a first natural gas processing device, 112 a second natural gas processing device, 113 a first valve, 114 a second valve, 115 a third valve; 201 first-stage air intake scrubber, 202 first-stage air intake buffer, 203 first-stage compression cylinder, 204 first-stage exhaust buffer, 205 first-stage air cooler, 206 second-stage air intake scrubber, 207 second-stage air intake buffer, 208 second-stage compression cylinder, 209 second-stage exhaust buffer, 210 second-stage air cooler, 211 second-stage exhaust separator, 212 second-stage exhaust filter; 218 second safety valve group, 219 first safety valve group; 301 the sixth valve, 302 the fourth valve, 303 the seventh valve, 304 the eighth valve, 305 the ninth valve, 306 the fifth valve, 307 the pneumatic switch valve, 308 the pneumatic regulating valve. DETAILED DESCRIPTION

[0021] An embodiment of the present application provides a natural gas reciprocating compressor unit.

[0022] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments of this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0023] The embodiment of the present application provides a natural gas reciprocating compressor unit 110 . Figure 1 A schematic diagram of a natural gas reciprocating compressor unit provided in an embodiment of the present application is shown in FIG. Figure 1As shown, the unit includes: a first natural gas processing device 111 and a second natural gas processing device 112, which are used to compress the incoming natural gas. A first valve 113, one end of which is connected to the gas inlet end of the first natural gas processing device 111, and the other end of which is connected to the gas inlet end of the second natural gas processing device 112. The first valve 113 is in an open state under a first condition, so that the incoming natural gas is compressed in parallel through the first natural gas processing device 111 and the second natural gas processing device 112, and the first valve 113 is in a closed state under a second condition. A second valve 114, one end of which is connected to the gas outlet end of the first natural gas processing device 111, and the other end of which is connected to the gas inlet end of the second natural gas processing device 112, and the second valve 114 is in an open state under the second condition, so that the natural gas after the primary compression enters the second natural gas processing device 112 for secondary compression; the second valve 114 is in a closed state under the first condition. The third valve 115 has one end connected to the gas outlet of the first natural gas processing device 111 and the other end connected to the gas outlet of the second natural gas processing device 112. The third valve 115 is in an open state under the first condition to allow the natural gas compressed in parallel to be mixed; the third valve 115 is in a closed state under the second condition.

[0024] Specifically, Figure 1 As shown, the natural gas reciprocating compressor unit 110 in the embodiment of the present application includes a first natural gas processing device 111, a second natural gas processing device 112 and a plurality of valves. It should be noted that the valve in the embodiment of the present application may be a ball valve or other types of valves, which are not limited in the embodiment of the present application. One end of the first valve 113 is connected to the gas inlet end of the first natural gas processing device 111, and the other end is connected to the gas inlet end of the second natural gas processing device 112. Under the first condition, the valve is in an open state, allowing natural gas to enter the first natural gas processing device 111 and the second natural gas processing device 112 at the same time for parallel compression, thereby improving compression efficiency and shortening processing time. One end of the second valve 114 is connected to the gas outlet end of the first natural gas processing device 111, and the other end is connected to the gas inlet end of the second natural gas processing device 112. Under the second condition, the valve is opened, so that the natural gas that has been compressed in the first stage can enter the second natural gas processing device 112 for further compression to ensure that the natural gas reaches sufficient pressure for storage. One end of the third valve 115 is connected to the gas outlet of the first natural gas processing device 111, and the other end is connected to the gas outlet of the second natural gas processing device 112. Under the first condition, the valve is opened so that the natural gas from the first natural gas processing device 111 and the second natural gas processing device 112 are mixed here. The embodiment of the present application can simultaneously meet the requirements of different pressures and flows in the gas injection cycle and the gas production cycle through one unit, which not only reduces the commissioning of equipment, reduces costs, but also reduces the floor space.

[0025] Furthermore, if Figure 1 As shown, under the first condition, the first valve 113 and the third valve 115 are in an open state, and the second valve 114 is in a closed state. Natural gas enters the first natural gas processing device 111, and simultaneously enters the second natural gas processing device 112 through the first valve 113. Natural gas is processed in parallel in the first natural gas processing device 111 and the second natural gas processing device 112 at the same time, and the gas processed by the first natural gas processing device 111 is mixed with the gas processed by the second natural gas processing device 112 through the third valve 115, and the mixed gas is produced.

[0026] Furthermore, if Figure 1 As shown, under the second condition, the first valve 113 and the third valve 115 are in a closed state, and the second valve 114 is in an open state. The natural gas enters the first natural gas processing device 111 for processing, and after processing, enters the second natural gas processing device 112 through the second valve 114, so as to be processed again in the second natural gas processing device 112, and the re-processed gas is stored.

[0027] In a feasible implementation, the first condition is the gas production stage, or the pressure difference between the gas inlet of the first natural gas processing device and the gas outlet of the second natural gas processing device is less than the first threshold. The second condition is the gas injection stage, or the pressure difference between the gas inlet of the first natural gas processing device and the gas outlet of the second natural gas processing device is greater than the first threshold.

[0028] The pressure difference between the inlet and outlet of natural gas is large during the gas injection stage, while it is small during the gas production stage. The compression stage of the gas injection stage is greater than that of the gas production stage. Therefore, the pressure difference value during the gas production stage is less than the first threshold value, while the pressure difference value during the gas injection stage is greater than the first threshold value. Or in other application stages, when the pressure difference between the inlet of the first natural gas processing device and the outlet of the second natural gas processing device is less than the first threshold value, the first condition is used, and when the pressure difference between the inlet of the first natural gas processing device and the outlet of the second natural gas processing device is greater than the first threshold value, the second condition is used.

[0029] In one possible implementation, Figure 2 A flowchart of a natural gas reciprocating compressor unit operation under a first condition provided in an embodiment of the present application, Figure 3 A flowchart of the operation of a natural gas reciprocating compressor unit under the second condition provided in an embodiment of the present application, Figure 4 A structural diagram of a natural gas reciprocating compressor unit provided in an embodiment of the present application, Figure 6 A schematic diagram of a first natural gas processing device provided in an embodiment of the present application, wherein: Figure 6 correspond Figure 4 The first natural gas processing unit. Figure 2 , Figure 3 , Figure 4 as well as Figure 6 As shown, the first natural gas processing device 111 includes: a first-stage air intake scrubber 201, which is used to filter the incoming natural gas. A first-stage air intake buffer 202, the air intake end of the first-stage air intake buffer 202 is connected to the air outlet end of the first-stage air intake scrubber 201, and is used to buffer the natural gas filtered by the first-stage air intake scrubber 201. A first-stage compression cylinder 203, the air intake end of the first-stage compression cylinder 203 is connected to the air outlet end of the first-stage air intake buffer 202, and is used to compress the natural gas buffered by the first-stage air intake buffer 202. A first-stage exhaust buffer 204, the air intake end of the first-stage exhaust buffer 204 is connected to the air outlet end of the first-stage compression cylinder 203, and is used to buffer the natural gas compressed by the first-stage compression cylinder 203. A first-stage air cooler 205, the air intake end of the first-stage air cooler 205 is connected to the air outlet end of the first-stage exhaust buffer 204, and is used to cool the natural gas buffered by the first-stage exhaust buffer 204.

[0030] Specifically, Figure 2 , Figure 3 , Figure 4 as well as Figure 6 As shown, the first-stage intake scrubber 201, the first-stage intake buffer 202, the first-stage compression cylinder 203, the first-stage exhaust buffer 204, and the first-stage air cooler 205 in the first natural gas processing device 111 are connected in sequence through pipelines. The natural gas from the upstream enters the first-stage intake buffer 202 after being filtered by the first-stage intake scrubber 201. After being buffered by the buffer, the natural gas enters the first-stage compression cylinder 203 of the compressor for primary compression. The compressed gas passes through the first-stage exhaust buffer 204 and enters the first-stage air cooler 205 through a pipeline for cooling.

[0031] In one possible implementation, Figure 2 A flowchart of a natural gas reciprocating compressor unit operation under a first condition provided in an embodiment of the present application, Figure 3 A flowchart of the operation of a natural gas reciprocating compressor unit under the second condition provided in an embodiment of the present application, Figure 4 A structural diagram of a natural gas reciprocating compressor unit provided in an embodiment of the present application, Figure 7 A schematic diagram of a second natural gas processing device provided in an embodiment of the present application, wherein: Figure 7 correspond Figure 4 The second natural gas processing unit. Figure 2 , Figure 3 , Figure 4 as well as Figure 7As shown, the second natural gas processing device 112 includes: a secondary air intake scrubber 206, which is used to filter the incoming natural gas. A secondary air intake buffer 207, the air intake end of the secondary air intake buffer 207 is connected to the air outlet end of the secondary air intake scrubber 206, and is used to buffer the natural gas filtered by the secondary air intake scrubber 206. A secondary compression cylinder 208, the air intake end of the secondary compression cylinder 208 is connected to the air outlet end of the secondary air intake buffer 207, and is used to compress the natural gas buffered by the secondary air intake buffer 207. A secondary exhaust buffer 209, the air intake end of the secondary exhaust buffer 209 is connected to the air outlet end of the secondary compression cylinder 208, and is used to buffer the natural gas compressed by the secondary compression cylinder 208. A secondary air cooler 210, the air intake end of the secondary air cooler 210 is connected to the air outlet end of the secondary exhaust buffer 209, and is used to cool the natural gas buffered by the secondary exhaust buffer 209.

[0032] Specifically, Figure 2 , Figure 3 , Figure 4 as well as Figure 7 As shown, the secondary air intake scrubber 206, the secondary air intake buffer 207, the secondary compression cylinder 208, the secondary exhaust buffer 209, and the secondary air cooler 210 in the second natural gas processing device 112 are connected in sequence through pipelines. The natural gas from the upstream enters the secondary air intake buffer 207 after being filtered by the secondary air intake scrubber 206. After being buffered by the buffer, the natural gas enters the secondary compression cylinder 208 of the compressor for secondary compression. The compressed gas passes through the secondary exhaust buffer 209 and enters the secondary air cooler 210 through a pipeline for cooling.

[0033] The embodiment of the present application meets the demand for gas injection and production of natural gas through a set of units, thus avoiding equipment idleness and improving equipment utilization. Under the first condition, the opening of the first valve 113 enables the first natural gas processing device 111 and the second natural gas processing device 112 to work in parallel and jointly process the incoming natural gas, thereby improving processing efficiency. Under the second condition, since a higher compression level is required, by adjusting the valve state, the natural gas after the first-stage compression directly enters the second natural gas processing device 112 for series compression, thereby meeting the compression requirements under high pressure difference.

[0034] Under the first condition, if Figure 2 , Figure 3 , Figure 4 , Figure 6 as well as Figure 7 As shown, taking the gas production process as an example: it is necessary to confirm in advance whether the first valve 113 is open, whether the second valve 114 is closed, and whether the third valve 115 is open.

[0035] Furthermore, the natural gas from the upstream enters the first-stage intake buffer 202 through the first-stage intake scrubber 201 for buffering, and then enters the first-stage compression cylinder 203 of the compressor. The compressed gas passes through the first-stage exhaust buffer 204 and enters the first-stage air cooler 205 for cooling through the pipeline; the other path passes through the second-stage intake scrubber 206 and enters the second-stage intake buffer 207 for buffering, and then enters the second-stage compression cylinder 208 of the compressor for compression. The compressed gas passes through the second-stage exhaust buffer 209 and enters the second-stage air cooler 210 for cooling through the pipeline. The two cooled gases are mixed and filtered by the second-stage exhaust separator 211 and the second-stage exhaust filter 212 before entering the downstream. The two paths are compressed simultaneously.

[0036] Under the second condition, if Figure 2 , Figure 3 , Figure 4 , Figure 6 as well as Figure 7 As shown, taking the gas injection process as an example: it is necessary to confirm in advance whether the first valve 113 is closed, whether the second valve 114 is open, and whether the third valve 115 is closed.

[0037] Furthermore, the natural gas from the upstream is filtered through the first-stage air intake scrubber 201 and then enters the first-stage air intake buffer 202. After being buffered by the buffer tank, it enters the first-stage compression cylinder 203 of the compressor for first-stage compression. The compressed gas passes through the first-stage exhaust buffer 204 and then enters the first-stage air cooler 205 through a pipeline for cooling. The cooled gas enters the second-stage air intake scrubber 206 for separation and then enters the second-stage air intake buffer 207 for buffering. The buffered gas enters the second-stage compression cylinder 208 of the compressor for second-stage compression. The compressed gas passes through the second-stage exhaust buffer 209 and then enters the second-stage air cooler 210 for cooling through a pipeline. The cooled gas enters the second-stage exhaust separator 211 and the second-stage exhaust filter 212 for filtration and then enters the downstream.

[0038] In a feasible implementation, the first energy consumption value corresponding to the first natural gas processing device 111 and the second energy consumption value corresponding to the second natural gas processing device 112 are obtained in real time, and the first energy consumption value and the second energy consumption value are compared with the corresponding energy consumption threshold value to determine the first energy consumption difference value. The energy consumption threshold value is the upper limit of energy consumption for economic operation set according to the operation history data. The volume of uncompressed natural gas is obtained, and the energy consumption value required for compression is determined based on the volume of uncompressed natural gas and the current compression condition (the first condition or the second condition). The first energy consumption difference value is compared with the energy consumption value required for compression completion to determine the second energy consumption difference value. The second energy consumption difference value can be used to determine whether the completion of the current compression task will exceed the energy consumption upper limit. If the first energy consumption difference is less than the energy consumption required to complete the compression, that is, it exceeds the energy consumption upper limit, the compression duration is determined based on the second energy consumption value, and when the compression duration is less than the preset duration, the first natural gas processing device 111 and the second natural gas processing device 112 are allowed to continue to perform the compression task. If the compression duration is not less than the preset duration, the compression pause time is determined and sent to the corresponding supervisor, indicating that the equipment has been working continuously for a long time and there is a risk of serious loss. Among them, the compression pause time is the compression time corresponding to the compression duration equal to the preset duration.

[0039] In one possible implementation, Figure 4 A structural diagram of a natural gas reciprocating compressor unit provided in an embodiment of the present application, Figure 8 A schematic diagram of a secondary exhaust filter 212 device provided in an embodiment of the present application. Figure 4 and Figure 8 As shown, the unit further includes a secondary exhaust separator 211 connected to the gas outlet end of the second natural gas processing device 112, and further includes a secondary exhaust filter 212 connected to the gas outlet end of the secondary exhaust separator 211. A bypass pipeline is provided between the gas outlet end of the secondary exhaust separator 211 and the gas outlet end of the secondary exhaust filter 212, and the bypass pipeline is provided with a fourth valve 302; a vent pipeline is provided at the gas outlet end of the secondary exhaust filter 212, and the vent pipeline is provided with a fifth valve 306; a sixth valve 301 is provided between the secondary exhaust separator 211 and the secondary exhaust filter 212; and a seventh valve 303 is provided between the secondary exhaust filter 212 and the downstream.

[0040] Specifically, Figure 4 and Figure 8As shown, in the embodiment of the present application, a sixth valve 301 is provided between the secondary exhaust separator 211 and the secondary exhaust filter 212. The separated natural gas can be transferred to the secondary exhaust filter 212 through the sixth valve 301 in the open state. A seventh valve 303 is provided between the secondary exhaust filter 212 and the downstream. The filtered natural gas can be transferred to the downstream through the seventh valve 303 in the open state. A bypass pipeline is provided between the gas outlet end of the secondary exhaust separator 211 and the gas outlet end of the secondary exhaust filter 212 in the embodiment of the present application. One end of the bypass pipeline is provided between the gas outlet of the secondary exhaust separator 211 and the sixth valve 301, and the other end of the bypass pipeline is provided between the seventh valve 303 and the downstream. A fourth valve 302 is provided on the bypass pipeline. The gas discharged from the secondary exhaust separator 211 can be transferred to the downstream through the bypass pipeline through the fourth valve 302 in the open state. In the embodiment of the present application, a vent pipe is provided at the gas outlet end of the secondary exhaust filter 212, and the air inlet of the vent pipe is provided between the gas outlet of the secondary exhaust filter 212 and the seventh valve 303. The natural gas in the secondary exhaust filter 212 can be discharged through the vent pipe in the open state.

[0041] In order to achieve the purpose of online replacement of the filter element of the secondary exhaust filter 212, when the filter element of the secondary exhaust filter 212 is replaced, the natural gas discharged from the secondary exhaust separator 211 is transferred to the downstream through the bypass pipeline, and the natural gas in the secondary exhaust filter 212 is discharged through the vent pipeline.

[0042] In a possible implementation, Figure 4 and Figure 8 As shown, when the filter element of the secondary exhaust filter 212 is replaced, the fourth valve 302 is in an open state, and the sixth valve 301 and the seventh valve 303 are both in a closed state, so as to transfer the natural gas discharged from the secondary exhaust separator 211 to the downstream through the bypass pipeline; the fifth valve 306 is in an open state, so as to discharge the natural gas in the secondary exhaust filter 212 through the venting pipeline. A nitrogen purge port is provided on the secondary exhaust filter 212, and the nitrogen purge port is used to purge nitrogen after the natural gas in the secondary exhaust filter 212 is discharged, so as to replace the filter element online.

[0043] Specifically, the secondary exhaust filter 212 in the embodiment of the present application is provided with a nitrogen purge port, which can realize online replacement of the filter element and reduce the start and stop of the machine.

[0044] Furthermore, in normal operation, the sixth valve 301 and the seventh valve 303 are in an open state, and the fourth valve 302 is in a closed state. When replacing the filter element online, the fourth valve 302 must be opened first, and then the sixth valve 301 and the seventh valve 303 must be closed, and the fifth valve 306 must be opened to release the natural gas in the container and then closed, and then nitrogen is purged through the eighth valve 304 and the ninth valve 305, each time pressurized to a preset pressure (e.g., 0.5 MPag), left to stand for a preset time (e.g., 2 minutes) and then released, and the filter element can be replaced after repeating the operation for a preset number of times (e.g., 4 times).

[0045] In a possible implementation, Figure 4 and Figure 7 As shown, the unit is provided with a return pipeline, one end of which is connected to the air inlet port of the unit, and the other end of which is connected to the air outlet port of the unit. A pneumatic regulating valve 308 and a pneumatic switch valve 307 are arranged in parallel on the return pipeline. When the unit is started, the pneumatic regulating valve 308 and the pneumatic switch valve 307 are both in an open state.

[0046] Specifically, the natural gas reciprocating compressor unit 110 in the embodiment of the present application is provided with a return pipeline, and the two ends of the return pipeline are connected to the air intake end and the exhaust end of the unit. The return pipeline is provided with a pneumatic regulating valve 308 and a pneumatic switch valve 307, and the two valves are connected in parallel and opened at the same time when the machine is started to reduce the start-up load; during normal operation, the regulating valve is used to adjust the flow.

[0047] In one possible implementation, Figure 5 A schematic diagram of a two-way safety valve group provided in an embodiment of the present application is shown in FIG. Figure 4 and Figure 5 As shown, the gas inlet end of the first natural gas processing device 111 of the unit, the first natural gas processing device 111 and the second natural gas processing device 112 are respectively provided with two-way safety valve groups.

[0048] Specifically, in the embodiment of the present application, two safety valve groups are respectively provided at the gas inlet end of the first natural gas processing device 111, the first natural gas processing device 111 and the second natural gas processing device 112. When the natural gas pressure value is greater than the corresponding safety value threshold, the outlet valve of the safety valve group is opened to reduce the pressure value.

[0049] In a possible implementation, Figure 4 and Figure 5As shown, the two-way safety valve group includes a first safety valve group 219 and a second safety valve group 218; under a first condition, the first safety valve group 219 is in an open state, and the second safety valve group 218 is in a closed state; under a second condition, the first safety valve group 219 is in a closed state, and the second safety valve group 218 is in an open state; wherein, the safety value threshold corresponding to the first safety valve group 219 is less than the safety value threshold corresponding to the second safety valve group 218, so as to adapt to the two operating conditions of the natural gas reciprocating compressor unit of the present application under the first condition and the second condition.

[0050] Specifically, the natural gas reciprocating compressor unit 110 in the embodiment of the present application is provided with two safety valves in the air intake pipeline and each exhaust pipeline, namely, the first safety valve group 219 and the second safety valve group 218. The safety valve setting values ​​are respectively applicable to different natural gas compression conditions to prevent the safety valve setting value from being too high due to satisfying two working conditions at the same time, thereby affecting the safe operation of the unit.

[0051] In a feasible implementation manner, the scrubber in the unit is provided with a glass plate level gauge and a differential pressure transmitter, and the glass plate level gauge is used to calibrate the reading of the differential pressure transmitter.

[0052] Specifically, the unit scrubber uses a glass plate level gauge and a differential pressure transmitter to meet the different requirements of liquid density under different compression conditions. The glass plate level gauge can be used as a calibration instrument for the differential pressure transmitter to prevent the differential pressure level transmitter from generating false liquid levels due to pressure fluctuations caused by density changes, thereby ensuring the accuracy of the liquid level and realizing remote transmission and real-time viewing.

[0053] In a feasible implementation manner, the unit is provided with an alarm device, and the alarm device corresponds to different alarm thresholds under the first condition and the second condition respectively.

[0054] Specifically, in the embodiment of the present application, the alarm shutdown values ​​of the pressure instrument and the temperature instrument of the unit are set separately, and the corresponding mode is selected when starting the unit under different compression conditions to ensure safe and reliable operation of the unit.

[0055] The natural gas reciprocating compressor unit in the embodiment of the present application can simultaneously meet the requirements of different pressures and flows under different compression conditions, which not only reduces the commissioning of equipment and reduces costs, but also reduces the floor space. The setting of the two-way safety valve can ensure the safe and reliable operation of the safety valve. The bypass setting of the filter can reduce the downtime caused by replacing the filter element and reduce the gas waste caused by downtime and venting.

[0056] Each embodiment in this application is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device, equipment, and non-volatile computer storage medium embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0057] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the embodiments of the present application may have various changes and variations. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application.

Claims

1. A natural gas reciprocating compressor unit, characterized in that: The unit comprises: a first natural gas processing unit and a second natural gas processing unit for compressing incoming natural gas; a first valve, one end of which is connected to the gas inlet end of the first natural gas processing device, and the other end of which is connected to the gas inlet end of the second natural gas processing device, the first valve being in an open state under a first condition so that the incoming natural gas is compressed in parallel through the first natural gas processing device and the second natural gas processing device, and the first valve being in a closed state under a second condition; a second valve, one end of which is connected to the gas outlet of the first natural gas processing device, and the other end of which is connected to the gas inlet of the second natural gas processing device, the second valve being in an open state under a second condition so that the natural gas after the primary compression enters the second natural gas processing device for secondary compression; the second valve being in a closed state under a first condition; a third valve, one end of which is connected to the gas outlet of the first natural gas processing device, and the other end of which is connected to the gas outlet of the second natural gas processing device, wherein the third valve is in an open state under a first condition to allow the natural gas compressed in parallel to be mixed; and the third valve is in a closed state under a second condition; Among them, the first condition is the gas production stage, or the pressure difference between the gas inlet of the first natural gas processing device and the gas outlet of the second natural gas processing device is less than a first threshold; the second condition is the gas injection stage, or the pressure difference between the gas inlet of the first natural gas processing device and the gas outlet of the second natural gas processing device is greater than the first threshold.

2. A natural gas reciprocating compressor unit according to claim 1, characterized in that: The first natural gas processing device comprises: A primary air intake scrubber, the primary air intake scrubber is used to filter the incoming natural gas; A first-stage air intake buffer, the air intake end of the first-stage air intake buffer is connected to the air outlet end of the first-stage air intake scrubber, and is used to buffer the natural gas filtered by the first-stage air intake scrubber; A first-stage compression cylinder, the air inlet end of the first-stage compression cylinder is connected to the air outlet end of the first-stage air inlet buffer, and is used to compress the natural gas buffered by the first-stage air inlet buffer; A first-stage exhaust buffer, the air inlet end of the first-stage exhaust buffer is connected to the air outlet end of the first-stage compression cylinder, and is used to buffer the natural gas compressed by the first-stage compression cylinder; A primary air cooler, wherein the air inlet end of the primary air cooler is connected to the air outlet end of the primary exhaust buffer, and is used to cool the natural gas buffered by the primary exhaust buffer.

3. A natural gas reciprocating compressor unit according to claim 1, characterized in that: The second natural gas processing device comprises: A secondary air intake scrubber, the secondary air intake scrubber is used to filter the incoming natural gas; A secondary air intake buffer, the air intake end of the secondary air intake buffer is connected to the air outlet end of the secondary air intake scrubber, and is used to buffer the natural gas filtered by the secondary air intake scrubber; A secondary compression cylinder, the air inlet end of the secondary compression cylinder is connected to the air outlet end of the secondary air inlet buffer, and is used to compress the natural gas buffered by the secondary air inlet buffer; A secondary exhaust buffer, the air inlet end of the secondary exhaust buffer is connected to the air outlet end of the secondary compression cylinder, and is used to buffer the natural gas compressed by the secondary compression cylinder; A secondary air cooler, wherein the air inlet end of the secondary air cooler is connected to the air outlet end of the secondary exhaust buffer, and is used to cool the natural gas buffered by the secondary exhaust buffer.

4. A natural gas reciprocating compressor unit according to claim 1, characterized in that: The unit further comprises a secondary exhaust separator connected to the gas outlet end of the second natural gas processing device, and further comprises a secondary exhaust filter connected to the gas outlet end of the secondary exhaust separator; A bypass pipeline is provided between the gas outlet end of the secondary exhaust separator and the gas outlet end of the secondary exhaust filter, and the bypass pipeline is provided with a fourth valve; The gas outlet end of the secondary exhaust filter is provided with a venting pipeline, and the venting pipeline is provided with a fifth valve; A sixth valve is provided between the secondary exhaust separator and the secondary exhaust filter; A seventh valve is provided between the secondary exhaust filter and the downstream.

5. A natural gas reciprocating compressor unit according to claim 4, characterized in that: When the filter element of the secondary exhaust filter is replaced, the fourth valve is in an open state, and the sixth valve and the seventh valve are both in a closed state, so as to transfer the natural gas discharged from the secondary exhaust separator to the downstream through the bypass pipeline; The fifth valve is in an open state to discharge the natural gas in the secondary exhaust filter through the vent line; The secondary exhaust filter is provided with a nitrogen purge port, which is used to purge nitrogen after the natural gas in the secondary exhaust filter is released, so as to replace the filter element online.

6. A natural gas reciprocating compressor unit according to claim 1, characterized in that: The unit is provided with a return pipeline, one end of which is connected to the air inlet port of the unit, and the other end of which is connected to the air outlet port of the unit; A pneumatic regulating valve and a pneumatic switching valve are arranged in parallel on the return pipeline. When the unit is started, the pneumatic regulating valve and the pneumatic switching valve are both in an open state.

7. The natural gas reciprocating compressor unit according to claim 1, characterized in that: The gas inlet end of the first natural gas processing device of the unit, the first natural gas processing device and the second natural gas processing device are respectively provided with two-way safety valve groups.

8. A natural gas reciprocating compressor unit according to claim 7, characterized in that: The two-way safety valve group includes a first safety valve group and a second safety valve group; Under the first condition, the first safety valve group is in an open state, and the second safety valve group is in a closed state; Under the second condition, the first safety valve group is in a closed state, and the second safety valve group is in an open state; Among them, the safety value threshold corresponding to the first safety valve group is smaller than the safety value threshold corresponding to the second safety valve group.

9. The natural gas reciprocating compressor unit according to claim 1, characterized in that: The scrubber in the unit is provided with a glass plate level gauge and a differential pressure transmitter, and the glass plate level gauge is used to calibrate the reading of the differential pressure transmitter.

10. The natural gas reciprocating compressor unit according to claim 1, characterized in that: The unit is provided with an alarm device, and the alarm device corresponds to different alarm thresholds under the first condition and the second condition respectively.

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