Phenol acetone plant oxidation tail gas pressure power generation device

Abstract

The utility model relates to phenol acetone technical field discloses a kind of oxidation tail gas pressure energy power generation devices of phenol acetone device, including inlet heater, oxidation tail gas pressure regulating valve is installed in the input end of inlet heater, the output end of inlet heater is installed with expander inlet regulating valve, the output end of expander inlet regulating valve is installed with turbine expander, the output end of turbine expander is installed with gear transmission box, the output end of gear transmission box is installed with asynchronous generator, the output end of inlet heater is installed with steam regulating valve, gear transmission box's output end is connected with lubricating oil system.The oxidation tail gas pressure energy power generation devices of phenol acetone device, oxidation tail gas turbine expansion generator set is stable and reliable in operation, various mechanical performance indexes and power generation capacity index reach design requirement, performance is good, oxidation tail gas turbine expansion generator set recycles excess pressure and generates electricity, reduces purchased electric energy, reaches the purpose of energy saving and emission reduction.

Description

Technical Field

[0001] This utility model relates to the field of phenol and acetone technology, specifically to a pressure energy power generation device for the oxidation tail gas of a phenol and acetone plant. Background Technology

[0002] In the process of producing phenol and acetone by the cumene process, cumene is reacted with air in an oxidation tower to prepare cumene hydroperoxide, which is then decomposed into phenol and acetone in subsequent processes. Oxidation tail gas containing various organic compounds is discharged from the top of the oxidation tower. After being cooled and cryogenically cooled, the oxidation tail gas is deliquified by a tail gas separator and then sent to an oxidation incinerator.

[0003] Currently, the pressure of the oxidation tail gas is controlled at around 300 kPa by an oxidation tail gas pressure control valve. Through the catalytic oxidation treatment process of the oxidation incinerator, the trace organic matter and harmful substances contained in the oxidation tail gas are converted into carbon dioxide and water. The high-temperature tail gas after incineration enters the waste heat boiler to generate superheated steam. After energy recovery, the tail gas is discharged into the atmosphere. During this process, the pressure difference before and after the regulating valve is large, which wastes pressure potential energy and causes energy waste. Utility Model Content

[0004] The purpose of this invention is to provide a pressure energy power generation device for the oxidation tail gas of a phenol-acetone plant, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a pressure energy power generation device for the oxidation tail gas of a phenol-acetone plant, comprising an inlet heater, an oxidation tail gas pressure regulating valve installed at the input end of the inlet heater, an expander inlet regulating valve installed at the output end of the inlet heater, a turbine expander installed at the output end of the expander inlet regulating valve, a gearbox installed at the output end of the turbine expander, an asynchronous generator installed at the output end of the gearbox, a steam regulating valve installed at the output end of the inlet heater, and a lubricating oil system connected to the output end of the gearbox.

[0006] The lubricating oil system includes a dual-cylinder fine filter installed at the input end of the lubricating oil system. An oil tank is installed at the output end of the lubricating oil system. An electric heater is installed inside the oil tank. A screw oil pump is connected to the output end of the oil tank. An oil cooler is connected to the input end of the screw oil pump.

[0007] Preferably, the oil cooler uses a shell-and-tube heat exchanger to cool the oil supply temperature to below 45°C.

[0008] Preferably, the asynchronous generator is a 10kV explosion-proof asynchronous generator with an explosion-proof rating of IIBT4, an outdoor corrosion-resistant type, a design life of 20 years, a squirrel-cage rotor, and the rotor structure is designed with reliable measures to prevent the squirrel cage bars from breaking. The mounting base is equipped with feet, it is horizontally installed, and the bearings are rolling bearings with grease lubrication.

[0009] Preferably, the inlet heater is connected to a steam pipeline, and a regulating valve is installed on the steam pipeline to regulate the steam consumption.

[0010] Preferably, a shut-off valve is installed at the inlet of the turbine expander. The oxidizing exhaust gas is depressurized and expanded by the turbine expander to do work. The output mechanical work is decelerated by a gearbox and drives an asynchronous generator to convert mechanical energy into electrical energy. The generated electrical energy is then fed into the power grid.

[0011] Preferably, the lubrication system uses two screw oil pumps, one in use and one on standby, and they can start automatically to each other.

[0012] Preferably, the dual-cylinder fine filter is a lubricating oil filter that can be switched online, with a filtration accuracy of 10µm. It integrates the turbine expander, gearbox, and generator skid together, providing sufficient strength and rigidity.

[0013] Preferably, the lubricating oil system is connected to the control system to achieve one-button start, interlocking and linkage protection.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] The oxidation tail gas pressure energy power generation device of the phenol and acetone unit is stable and reliable in operation. The various mechanical performance indicators and power generation indicators meet the design requirements and have good performance. The oxidation tail gas turbine expander generator unit recovers the residual pressure for power generation, reducing the purchase of external electricity and achieving the purpose of energy conservation and emission reduction. The oxidation tail gas turbine expander generator unit is simple to operate, has low operating cost, strong adaptability to working conditions, and high automation and safety performance. It provides a new idea and solution for the comprehensive utilization of oxidation tail gas residual pressure energy in phenol and acetone units.

[0016] The oxidation tail gas pressure energy power generation device of the phenol and acetone plant uses a tail gas residual pressure turbine expander to recover the pressure energy during the decompression process of the oxidation tail gas. Through energy conversion, the pressure energy of the oxidation tail gas is used to drive the impeller to rotate and do work, thereby driving the generator to generate electricity, achieving the purpose of energy saving and efficiency improvement, and improving the comprehensive energy utilization rate of the enterprise. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the system flow of this utility model;

[0018] Figure 2This is a schematic diagram of the lubricating oil system of this utility model.

[0019] In the diagram: 1. Inlet heater; 2. Turbine expander; 3. Lubricating oil system; 4. Gearbox; 5. Asynchronous generator; 6. Oxidation exhaust gas pressure regulating valve; 7. Expander inlet regulating valve; 8. Steam regulating valve; 9. Oil cooler; 10. Dual-cylinder fine filter; 11. Electric heater; 12. Screw oil pump; 13. Oil tank. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Please see Figure 1-2 The present invention provides the following technical solution:

[0022] An oxidation tail gas pressure energy power generation device for a phenol-acetone plant includes an inlet heater 1 connected to a steam pipeline. A start-up regulating valve is installed on the steam pipeline to regulate the steam consumption. An oxidation tail gas pressure regulating valve 6 is installed at the input end of the inlet heater 1, and an expander inlet regulating valve 7 is installed at the output end of the inlet heater 1. A turbine expander 2 is installed at the output end of the expander inlet regulating valve 7, and a gearbox 4 is installed at the output end of the expander 2. An asynchronous generator 5 is installed at the output end of the gearbox 4. A shut-off valve is installed at the inlet of the expander 2. The oxidation tail gas undergoes depressurization and expansion through the expander 2, performing work. The output mechanical work is decelerated by the gearbox 4, driving the asynchronous generator 5 to convert mechanical energy into electrical energy. The generated electrical energy is fed into the power grid. The asynchronous generator 5 is a 10kV explosion-proof asynchronous generator with an explosion-proof rating of IIBT4, an outdoor corrosion-resistant type, a design life of 20 years, and a squirrel-cage rotor. The rotor structure is designed with reliable measures to prevent squirrel cage bar breakage. The mounting base is equipped with feet and is horizontally mounted. The bearings are rolling bearings with grease lubrication. A steam regulating valve 8 is installed at the output end of the inlet heater 1. The output end of the gearbox 4 is connected to the lubricating oil system 3. The lubricating oil system 3 is connected to the control system, which can realize one-button start, interlocking and linkage protection.

[0023] The lubricating oil system 3 includes a dual-cylinder fine filter 10. The lubricating oil system 3 uses two screw oil pumps 12, one in operation and one on standby, which can start automatically. The dual-cylinder fine filter 10 is installed at the input end of the lubricating oil system 3. The dual-cylinder fine filter 10 is a lubricating oil filter that can be switched online. The filtration accuracy is 10μm. The turbine expander 2, gearbox 4, and asynchronous generator 5 are skid-mounted together, which has sufficient strength and rigidity. An oil tank 13 is installed at the output end of the lubricating oil system 3. An electric heater 11 is installed inside the oil tank 13. The output end of the oil tank 13 is connected to the screw oil pump 12. The input end of the screw oil pump 12 is connected to the oil cooler 9. The oil cooler 9 uses a shell-and-tube heat exchanger to cool the oil supply temperature to below 45℃.

[0024] When in use, add sufficient and suitable machine oil to the oil tank 13 in the lubrication system 3 through the top oil filling port, start the electric heater 11, and automatically adjust to control the oil temperature at 25-40℃. The electric heater 11 is generally used in winter or when the equipment is not used for a long time. Circulate water from the oil cooler 9 in the lubrication system 3 is also used.

[0025] Turn on the screw oil pump 12 to maintain the oil supply pressure at 0.25 MPa. Pay attention to the pressure difference before and after the dual-cylinder fine filter 10. If the pressure difference increases, switch and clean it in time. Open the low-pressure nitrogen pipeline manual valve and introduce sealing isolation gas into the oil tank 13. Perform a rotation check on the unit.

[0026] The starting conditions are met, namely, normal oil supply pressure, normal oil supply temperature, and normal turning gear operation.

[0027] Slowly open the expansion inlet regulating valve 7 of the turbine expander 2 to introduce the oxidation tail gas of the phenol-acetone unit, thereby increasing the speed of the turbine expander 2. During the speed increase, slowly close the oxidation tail gas pressure regulating valve 6, and maintain the oxidation tail gas system pressure at 300 kPa during adjustment.

[0028] During the acceleration process, the oxidation tail gas of the phenol-acetone unit first passes through the inlet heater 1. The inlet heater 1 regulates the steam through the steam regulating valve 8, so that the tail gas is heated to 115°C and then enters the turbine expander 2. After expansion and work, the turbine outlet temperature drops to 35°C and goes to the oxidation incinerator.

[0029] When starting the turbine expander 2, strictly control the unit's speed increase and load loading rate. During the speed increase process, the opening of the inlet regulating valve should be increased slowly, and the unit's speed increase and load loading rate should be strictly controlled. During system operation, the bearing temperature and vibration value should be closely monitored to ensure they are reasonable. The specific process is as follows:

[0030] First stage of speed increase: After the turbine expander 2 starts up, the speed is increased to 1900 r / min and maintained.

[0031] Run for 10 minutes to confirm that the speed display is correct.

[0032] The second stage of speed increase: Gradually increase the speed to 3300 r / min, maintain operation for 3 minutes, check for any abnormal noises on site, and then quickly increase to 5200 r / min (the turbine speed is in the resonance zone between 3750 r / min and 4950 r / min, and the time should be controlled within 10 seconds. At the same time, the vibration of the unit should be closely monitored).

[0033] The third stage is speed increase: gradually increase the speed to 8350 r / min (pause for 1 minute in between), observe whether there are any abnormal noises from the unit, and observe whether the unit vibration, bearing temperature and other indicators are within the normal range.

[0034] The speed of turbine expander 2 is controlled between 8059 r / min and 8440 r / min, and the DCS in the central control room displays "grid connection permitted".

[0035] Phase 4: The central control room performs grid connection operation, and the turbine expander 2 drives the gearbox 4 to work the asynchronous generator 5.

[0036] After the unit is connected to the grid, immediately bring the unit to the initial load to prevent reverse power operation, control the power generation at about 40kW to 50kW, keep it running for 5 minutes, continue to open the expander inlet regulating valve 7 of the turbine expander 2 to introduce the oxidation tail gas of the phenol acetone unit, close the oxidation tail gas pressure regulating valve 6, maintain the oxidation tail gas system pressure at 300kpa during adjustment, and gradually increase the power generation to full load.

[0037] The equipment is currently operating stably, successfully converting the residual pressure of the oxidation tail gas into electrical energy, and can precisely control the pressure of upstream and downstream processes to ensure stable production. It has achieved a balance between energy recovery and safe operation. The turbine expander generator is equipped with an asynchronous generator 5 with a total installed capacity of 1000kW and adopts asynchronous grid connection.

[0038] Calculations show that after commissioning, the unit will generate 7 million kilowatt-hours of electricity annually, which is equivalent to saving 2,800 tons of standard coal and reducing carbon dioxide emissions by nearly 7,000 tons per year.

[0039] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pressure energy power generation device for the oxidation tail gas of a phenol-acetone plant, comprising an inlet heater (1), characterized in that: An oxidation tail gas pressure regulating valve (6) is installed at the input end of the inlet heater (1), an expander inlet regulating valve (7) is installed at the output end of the inlet heater (1), a turbine expander (2) is installed at the output end of the expander inlet regulating valve (7), a gearbox (4) is installed at the output end of the turbine expander (2), an asynchronous generator (5) is installed at the output end of the gearbox (4), a steam regulating valve (8) is installed at the output end of the inlet heater (1), and a lubricating oil system (3) is connected to the output end of the gearbox (4). The lubricating oil system (3) includes a double-cylinder fine filter (10). The double-cylinder fine filter (10) is installed at the input end of the lubricating oil system (3). An oil tank (13) is installed at the output end of the lubricating oil system (3). An electric heater (11) is installed inside the oil tank (13). A screw oil pump (12) is connected to the output end of the oil tank (13). An oil cooler (9) is connected to the input end of the screw oil pump (12).

2. The oxidative tail gas pressure energy power generation device of a phenol-acetone plant according to claim 1, characterized in that: The oil cooler (9) uses a shell-and-tube heat exchanger to cool the oil supply temperature to below 45°C.

3. The oxidative tail gas pressure energy power generation device of a phenol-acetone plant according to claim 2, characterized in that: The asynchronous generator (5) is a 10kV explosion-proof asynchronous generator with an explosion-proof rating of IIBT4. It is an outdoor corrosion-resistant type with a design life of 20 years. It has a squirrel cage rotor with a rotor structure design that has reliable measures to prevent the squirrel cage bars from breaking. The mounting base has feet and is installed horizontally. The bearings are rolling bearings with grease lubrication.

4. The oxidative tail gas pressure energy power generation device of a phenol-acetone plant according to claim 3, characterized in that: The inlet heater (1) is connected to the steam pipeline, and a regulating valve is installed on the steam pipeline to regulate the amount of steam used.

5. A pressure energy power generation device for the oxidation tail gas of a phenol-acetone unit according to claim 4, characterized in that: A shut-off valve is installed at the inlet of the turbine expander (2). The oxidizing exhaust gas is depressurized and expanded by the turbine expander (2) to do work. The output mechanical work is decelerated by the gearbox (4) and drives the asynchronous generator (5) to convert mechanical energy into electrical energy. The generated electrical energy is then fed into the power grid.

6. The oxidative tail gas pressure energy power generation device of a phenol-acetone plant according to claim 5, characterized in that: The lubrication system (3) uses two screw oil pumps (12), one in use and one on standby, and they can start automatically.

7. A pressure energy power generation device for the oxidation tail gas of a phenol-acetone plant according to claim 6, characterized in that: The dual-cylinder fine filter (10) is a lubricating oil filter that can be switched online, with a filtration accuracy of 10µm.

8. A pressure energy power generation device for the oxidation tail gas of a phenol-acetone plant according to claim 7, characterized in that: The lubricating oil system (3) is connected to the control system to achieve one-button start, interlock and linkage protection.

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