Energy-saving system of ethylene oxide recycle gas compressor

Abstract

The utility model discloses a recycle gas compressor energy-saving system of an ethylene oxide device, which belongs to the technical field of ethylene oxide production and comprises an EO absorption tower, a recycle gas compressor, a recycle gas compressor surface cooler, an EO desorption tower, an EO desorption tower reboiler, a secondary cooler, an EO lean and rich absorption liquid plate heat exchanger a, a light component removal tower reboiler and an EO refining tower reboiler. The EO desorption tower kettle pump and the newly added EO lean and rich absorption liquid plate heat exchanger b can be used for reutilizing the circulating water return of the circulating gas compressor surface air cooler, and the shell pass of the EO lean and rich absorption liquid plate heat exchanger b is connected with the EO refining tower reboiler, the EO lean and rich absorption liquid plate heat exchanger a and the EO desorption tower through pipelines. The energy utilization efficiency is improved, the cooling capacity of circulating water is fully utilized, the circulating water quantity of the device is reduced, and the technology is mainly applied to ethylene oxide production.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical production equipment, and particularly relates to an energy-saving system for a circulating gas compressor. Background Art

[0002] In the ethylene oxide unit, the circulating gas compressor energy-saving equipment is a common equipment. The circulating gas compressor serves as a power source, and sends the circulating gas with EO products coming out of the EO reactor to the secondary product cooler to the EO absorption tower to become the rich EO absorption liquid with a temperature of about 40°C. After passing through various heat exchangers and the lean EO absorption liquid with a temperature of about 125°C coming out of the EO analysis tower, heat and cold exchange is carried out to maintain the EO lean and rich liquid circulation.

[0003] At present, the only heat exchanger for EO lean and rich liquid circulation exchange temperature is EO lean and rich absorption liquid plate heat exchanger, which has too much cold and heat loss, resulting in waste of steam and circulating water, thereby increasing energy consumption and operating costs. The applicant has found through research that through certain technical improvements, this cold energy can be recycled and reused, while also saving energy consumption of circulating water. Utility Model Content

[0004] In order to solve the technical problems raised in the background technology, this design provides an ethylene oxide circulating gas compressor energy-saving system, and the technical solutions adopted are as follows:

[0005] An ethylene oxide circulating gas compressor energy-saving system, comprising an EO absorption tower, a circulating gas compressor, a circulating gas compressor surface cooler, an EO analysis tower, an EO analysis tower reboiler, a secondary product cooler, an EO lean and rich absorption liquid plate heat exchanger a, a light component removal tower reboiler, an EO refining tower reboiler and a tower kettle pump;

[0006] The EO absorption tower is connected to the secondary product cooler through a pipeline, and a flow meter a and a flow control valve a are arranged on the connected pipeline. The secondary product cooler is connected to the EO lean and rich absorption liquid plate heat exchanger a through a pipeline. The EO lean and rich absorption liquid plate heat exchanger a is connected to the EO lean and rich absorption liquid plate heat exchanger b through a pipeline, and a thermometer a and a thermometer b are arranged in the middle of the connected pipeline. The thermometer a and the thermometer b are used to monitor the temperature in real time. The EO lean and rich absorption liquid plate heat exchanger b is connected to the EO analysis tower through a pipeline;

[0007] The EO analysis tower is connected to the tower kettle pump through a pipeline, and the EO analysis tower is connected to the EO analysis tower reboiler through a pipeline.

[0008] The EO absorption tower is connected with the EO lean and rich absorption liquid plate heat exchanger a through a pipeline, and a flow meter b and a flow control valve b are arranged on the connected pipeline.

[0009] The core improvement of the utility model is that the front part of the EO lean-rich absorption liquid plate heat exchanger b is connected to the circulating gas compressor surface cooler through a pipeline, and the connected pipelines are respectively provided with a thermometer d, a gate valve a and a gate valve b, and the rear part of the EO lean-rich absorption liquid plate heat exchanger b is connected to the circulating water network through a pipeline;

[0010] The EO rich-poor absorption liquid plate heat exchanger b is connected with the light component removal tower reboiler, the EO refining tower reboiler, the tower kettle pump and the EO analysis tower in sequence through pipelines.

[0011] Preferably: the EO absorption tower is provided with four layers of fillers from top to bottom.

[0012] Preferably, the EO analysis tower is of full vacuum design, so as to avoid negative pressure caused by too fast cooling.

[0013] Preferably: an online EO detection instrument and a pressure gauge are provided at the top of the EO analysis tower, and a thermometer c is provided at the bottom of the EO analysis tower. The above design is used to detect the separation effect of the EO analysis tower and the overall temperature control.

[0014] Preferably: the steam is connected to the EO analysis tower reboiler through a pipeline and a flow meter c and a flow control valve c are provided on the connected pipeline. The heat source of the EO analysis tower reboiler is 0.5Mpa process steam, and the amount of steam added is accurately controlled by the flow meter c and the flow regulating valve c. The steam condensate generated by the steam condensate returns to the 0.5Mpa condensate pipeline network.

[0015] The working principle of the utility model is as follows:

[0016] The utility model mainly reuses the circulating return water of the circulating gas compressor surface cooler as the circulating feed water of the EO lean-rich absorption liquid plate heat exchanger b, and returns the EO lean-rich liquid in the shell layer of the EO lean-rich absorption liquid plate heat exchanger b to the circulating water main network after reaching 34°C;

[0017] The EO analysis tower receives the EO lean and rich absorption liquid through the pipeline. The rich EO absorption liquid passed through the shell process of the plate heat exchanger b passes through the EO analysis tower reboiler to provide heat source. About 80% of the gas phase ethylene oxide is sent to the ethylene oxide refining system through the online EO detector at the top of the EO analysis tower.

[0018] In order to reduce energy loss and increase heat exchange, the EO rich and poor absorption liquids pass through multiple reboilers and heat exchangers, with thermometers in between.

[0019] The kettle of the EO analysis tower is provided with a thermometer d, and the kettle temperature of the EO analysis tower is controlled at 125-130°C. The reboiler of the EO analysis tower uses process steam of 0.5Mpa and a temperature of 158°C.

[0020] Compared with the prior art, the utility model has the following beneficial effects: the utility model connects the front part of the tube side of the EO poor-rich absorption liquid plate heat exchanger b with the circulating gas compressor surface cooler through a pipeline, connects the rear part of the tube side of the EO poor-rich absorption liquid plate heat exchanger b with the circulating water network through a pipeline, and connects the shell side of the EO poor-rich absorption liquid plate heat exchanger b with the EO refining tower reboiler, the EO poor-rich absorption liquid plate heat exchanger a, and the EO analysis tower through a pipeline, and reuses the circulating water of the circulating gas compressor surface cooler to reduce the use of circulating water to save the operating cost of the device, thereby ultimately achieving the effect of energy saving, meeting the national requirements for energy saving and environmental protection, and achieving positive results in the actual application process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a working principle diagram of the utility model. DETAILED DESCRIPTION

[0022] Example 1

[0023] like Figure 1 As shown:

[0024] An ethylene oxide circulating gas compressor energy-saving system comprises an EO absorption tower 2, a circulating gas compressor 16, a circulating gas compressor surface cooler 17, an EO analysis tower 24, an EO analysis tower reboiler 21, a secondary product cooler 5, an EO lean and rich absorption liquid plate heat exchanger a8, a light component removal tower reboiler 19, an EO refining tower reboiler 20 and a tower kettle pump 26, wherein the EO absorption tower 2 is provided with four layers of fillers 1 from top to bottom;

[0025] The EO absorption tower 2 is connected to the secondary product cooler 5 through a pipeline, and a flow meter a4 and a flow control valve a3 are arranged on the connected pipeline. The secondary product cooler 5 is connected to the EO poor and rich absorption liquid plate heat exchanger a8 through a pipeline. The EO poor and rich absorption liquid plate heat exchanger a8 is connected to the EO poor and rich absorption liquid plate heat exchanger b11 through a pipeline, and a thermometer a9 and a thermometer b10 are arranged in the middle of the connected pipeline. The EO poor and rich absorption liquid plate heat exchanger b11 is connected to the EO analysis tower 24 through a pipeline. The EO analysis tower 24 is of full vacuum design. An online EO detection instrument 27 and a pressure gauge 25 are arranged on the top of the EO analysis tower 24, and a thermometer c12 is arranged on the bottom of the EO analysis tower 24.

[0026] The EO analysis tower 24 is connected to the tower kettle pump 26 through a pipeline, and the EO analysis tower 24 is connected to the EO analysis tower reboiler 21 through a pipeline.

[0027] The EO absorption tower 2 is connected to the EO rich-poor absorption liquid plate heat exchanger a8 through a pipeline, and a flow meter b7 and a flow control valve b6 are provided on the connected pipeline, which is characterized in that:

[0028] The front part of the EO lean-rich absorption liquid plate heat exchanger b11 is connected to the circulating gas compressor surface cooler 17 through a pipeline, and the connected pipelines are respectively provided with a thermometer d, a gate valve a and a gate valve b, and the rear part of the EO lean-rich absorption liquid plate heat exchanger b pipe side is connected to the circulating water network through a pipeline;

[0029] The EO rich-poor absorption liquid plate heat exchanger b is connected with the light component removal tower reboiler, the EO refining tower reboiler, the tower kettle pump and the EO analysis tower in sequence through pipelines.

[0030] The working principle of the utility model is as follows:

[0031] The bottom of the EO analysis tower 24 is controlled at 125-130°C. The EO analysis tower 24 controls the temperature of about 80% of the EO gas at the top to go to the EO refining system for detection by the EO online instrument 27. The bottom of the tower is a poor EO absorption liquid with trace epoxy, which is connected to the EO refining tower reboiler 20, the light component removal tower reboiler 19, the EO poor and rich absorption liquid plate heat exchanger b11, the EO poor and rich absorption liquid plate heat exchanger a8, and the secondary product cooler 5 in sequence through pipelines by the bottom pump 26. The circulating water supply of the circulating gas compressor surface cooler 17 is controlled by the gate valve c18 to control the total amount of circulating water. The circulating water supply of the EO poor and rich absorption liquid plate heat exchanger b11 connected through the pipeline is controlled by the gate valve a14 and the gate valve b15, and the circulating water return of the EO poor and rich absorption liquid plate heat exchanger 2 is controlled by the gate valve d28.

[0032] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An ethylene oxide circulating gas compressor energy-saving system, comprising an EO absorption tower (2), a circulating gas compressor (16), a circulating gas compressor surface cooler (17), an EO analysis tower (24), an EO analysis tower reboiler (21), a secondary product cooler (5), an EO lean and rich absorption liquid plate heat exchanger a (8), a light component removal tower reboiler (19), an EO refining tower reboiler (20) and a tower kettle pump (26); The EO absorption tower (2) is connected to the secondary product cooler (5) through a pipeline, and a flow meter a (4) and a flow control valve a (3) are arranged on the connected pipeline. The secondary product cooler (5) is connected to the EO lean and rich absorption liquid plate heat exchanger a (8) through a pipeline. The EO lean and rich absorption liquid plate heat exchanger a (8) is connected to the EO lean and rich absorption liquid plate heat exchanger b (11) through a pipeline, and a thermometer a (9) and a thermometer b (10) are arranged in the middle of the connected pipeline. The EO lean and rich absorption liquid plate heat exchanger b (11) is connected to the EO analysis tower (24) through a pipeline. The EO analysis tower (24) is connected to the tower kettle pump (26) through a pipeline, and the EO analysis tower (24) is connected to the EO analysis tower reboiler (21) through a pipeline. The EO absorption tower (2) is connected to the EO rich-poor absorption liquid plate heat exchanger a (8) through a pipeline, and a flow meter b (7) and a flow control valve b (6) are provided on the connected pipeline, characterized in that: The front part of the EO rich-poor absorption liquid plate heat exchanger b (11) is connected to the circulating gas compressor surface cooler (17) through a pipeline, and the connected pipelines are respectively provided with a thermometer d (13), a gate valve a (14) and a gate valve b (15), and the rear part of the EO rich-poor absorption liquid plate heat exchanger b (11) is connected to the circulating water network through a pipeline; The EO rich-poor absorption liquid plate heat exchanger b (11) is connected to the light component removal tower reboiler (19), the EO refining tower reboiler (20), the tower kettle pump (26) and the EO analysis tower (24) in sequence through pipelines.

2. The ethylene oxide circulating gas compressor energy-saving system according to claim 1, characterized in that: The EO absorption tower (2) is provided with four layers of fillers (1) from top to bottom.

3. The ethylene oxide circulating gas compressor energy-saving system according to claim 1, characterized in that: The EO analysis tower (24) is of full vacuum design.

4. The ethylene oxide circulating gas compressor energy-saving system according to claim 1, characterized in that: An online EO detection instrument (27) and a pressure gauge (25) are provided on the top of the EO analysis tower (24).

5. The ethylene oxide circulating gas compressor energy-saving system according to claim 1, characterized in that: A thermometer c (12) is provided at the bottom of the EO analysis tower (24).

6. The ethylene oxide circulating gas compressor energy-saving system according to claim 1, characterized in that: The steam is connected to the EO analysis tower reboiler (21) through a pipeline, and a flow meter c (22) and a flow control valve c (23) are provided on the connected pipeline.

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