Conduction oil temperature control device of biodiesel distillation production gas furnace

Abstract

The utility model discloses a heat-conducting oil temperature control device for a biodiesel distillation production gas furnace. The heat-conducting oil temperature control device comprises a distillation tower, a reboiler, a high-temperature circulating pump, a heat-conducting oil furnace circulating pump, a servo electric gas butterfly valve, a temperature control system and a heat-conducting oil furnace, the temperature control system comprises a temperature adjusting servo motor SM, a digital display thermometer, an electronic controller, an electric cabinet, a newly-added PLC and a computer, the electronic controller comprises a manual big fire button switch, a manual small fire button switch, a control state change-over switch, a PLC and a display screen, and the electronic controller is connected with the servo electric gas butterfly valve and the digital display thermometer through signal lines; and the newly added PLC is respectively connected with the computer, the manual big fire button switch, the manual small fire button switch and the control state change-over switch through signal lines. The utility model solves the problems that the conduction oil temperature control of the conduction oil temperature control device of the biodiesel distillation production gas furnace is inaccurate in an automatic control state, and the labor intensity is high and the temperature stability is difficult to ensure in a manual control state.

Description

Technical Field

[0001] The utility model relates to the technical field of organic chemical product biodiesel production equipment, in particular to a heat transfer oil temperature control device for a biodiesel distillation production gas furnace. Background Art

[0002] Industrial production of biodiesel generally uses waste animal and plant oils as raw materials. After the raw oil is purified, it undergoes a two-step chemical process of methyl esterification and ester exchange at a specific temperature to produce crude biodiesel, and then undergoes high-vacuum continuous reduced-pressure distillation to obtain finished biodiesel; after the crude methyl ester enters the biodiesel distillation tower, the heat transfer oil is heated to 250°C through a heat transfer oil furnace. At -0.05MPa, different types of qualified biodiesel products are obtained from different distillation towers according to different boiling points. Since heat transfer oil furnaces generally use natural gas as fuel, they are also called gas furnaces; the heat medium of the distillation tower is heat transfer oil, which is heated in the boiler room and then transported to the reboiler of the distillation tower through a pipeline; since the temperature fluctuation of the heat transfer oil has a great influence on the operating stability of the distillation tower, and the application market has increasingly higher requirements for the sulfur content of biodiesel, the temperature of the heat transfer oil is required to be stable, and the temperature difference of the heat transfer oil in production should be controlled within plus or minus 0.5°C. Usually, the gas thermal oil furnace burner is equipped with a burner temperature control system, which generally has two states: manual and automatic. In actual production, if the burner control table sets the temperature to the automatic control state, the temperature difference of the thermal oil can only be controlled at the level of plus or minus 3°C, which cannot meet the production requirements. Therefore, the burner control table can only set the temperature to the manual state, that is, manually control the manual button. However, this operation method increases the workload of the operator on the one hand, and on the other hand, it is difficult to control the thermal oil temperature due to the greater influence of human factors, and it is difficult to ensure temperature stability. Summary of the invention

[0003] The utility model aims to provide a heat transfer oil temperature control device for a biodiesel distillation production gas furnace, which has the advantages of accurate heat transfer oil temperature control, convenient and efficient operation, low labor intensity, and safe and reliable production. The utility model solves the problems of inaccurate heat transfer oil temperature control in the automatic control state and high labor intensity and difficulty in ensuring temperature stability in the manual control state in the heat transfer oil temperature control device for the biodiesel distillation production gas furnace in the prior art.

[0004] To achieve the above purpose, the utility model of the biodiesel distillation production gas furnace heat transfer oil temperature control device comprises a distillation tower 1, a reboiler 2, a high temperature circulation pump 3, a heat transfer oil furnace circulation pump 4, a servo electric gas butterfly valve 5, a temperature control system 6, a heat transfer oil furnace 14 and connecting pipes and valves; the middle of the distillation tower 1 is provided with a distillation tower crude methyl ester feed inlet a, the top is provided with a distillation tower vacuum outlet b, the middle and upper part is provided with a distillation tower biodiesel outlet c, the lower side is provided with a distillation tower reboiler vapor phase inlet d, and the bottom is 150mm away from the center. A distillation tower heavy oil outlet e is provided at the center, and a distillation tower reboiler circulation outlet f is provided at the center of the bottom; a reboiler biodiesel inlet g1 is provided at the top of the reboiler 2, a reboiler biodiesel outlet g2 is provided at the bottom, a reboiler heat transfer oil outlet h1 is provided at the upper left side, and a reboiler heat transfer oil inlet h2 is provided at the lower left side; a burner natural gas inlet i is provided at the center of the left side of the heat transfer oil furnace 14, a heat transfer oil furnace tail gas outlet j is provided at the center of the right side, a heat transfer oil furnace heat transfer oil outlet k is provided at the bottom, and a heat transfer oil furnace heat transfer oil outlet is provided at the top. hot oil inlet l; the distillation tower reboiler circulation outlet f is connected to the reboiler biodiesel inlet g1 after being connected to the high-temperature circulation pump 3, and the reboiler biodiesel outlet g2 is connected to the distillation tower reboiler vapor phase inlet d; the reboiler heat transfer oil outlet h1 is connected to the heat transfer oil inlet l of the heat transfer oil furnace, and the heat transfer oil outlet k of the heat transfer oil furnace is connected to the reboiler heat transfer oil inlet h2 after being connected to the heat transfer oil furnace circulation pump 4; the temperature control system 6 includes a temperature adjustment servo motor SM, a digital display thermometer with a temperature sensor 7, an electronic controller 8, An external common electric control box 12, a newly added PLC and a computer 13, the electronic controller 8 includes a manual high-fire button switch 9, a manual low-fire button switch 10, a control state conversion switch 11, a PLC and a display screen, which are respectively connected to the servo electric gas butterfly valve 5 and the digital display thermometer 7 arranged on the reboiler heat transfer oil inlet pipeline through signal lines; the newly added PLC is respectively connected to the computer 13, the manual high-fire button switch 9, the manual low-fire button switch 10, and the control state conversion switch 11 through signal lines.

[0005] During the high vacuum distillation production process of biodiesel, the temperature of various parts of the material in the distillation tower 1 has a great influence on the quality of the biodiesel product, especially the sulfur content of biodiesel determines the product price. On the other hand, the temperature fluctuation of various parts of the material in the distillation tower 1 affects the yield of the main product. According to long-term production experiments, the temperature difference of the heat transfer oil should be controlled within plus or minus 0.5 degrees.

[0006] The working principle of the temperature control system 6 when in the automatic state is to set the temperature limit of the heat transfer oil inlet of the reboiler 2, the temperature sensor sends a signal to the newly added PLC, the temperature regulating valve TV automatically opens and automatically adjusts the size of the natural gas servo electric gas butterfly valve 5, that is, the size of the gas entering the heat transfer oil furnace burner is used to control the temperature of the heat transfer oil furnace, thereby ensuring the temperature limit of the heat transfer oil inlet of the reboiler 2. In the actual production process of biodiesel distillation, when the temperature control system 6 is in the automatic state, the temperature difference of the heat transfer oil inlet temperature limit of the reboiler 2 can only be controlled within plus or minus 3 degrees, which is not conducive to production, but can be used for normal start and stop to use the automatic state; the working principle of the temperature control system 6 when in the manual state is to set the temperature limit of the heat transfer oil inlet of the reboiler 2, the temperature sensor sends a signal to the PLC, and the servo electric gas butterfly valve 5 size opening is manually operated on the computer according to the process setting temperature, that is, the size of the gas entering the heat transfer oil furnace burner is used to control the temperature of the heat transfer oil furnace, thereby ensuring that the temperature difference of the heat transfer oil inlet of the reboiler 2 is controlled within plus or minus 0.5 degrees, which can meet the high precision requirements of biodiesel production.

[0007] The electronic controller 8 in the above-mentioned temperature control system 6 adopts the Siemens electronic proportional combustion program controller system, which was purchased from the market in January 2023. Its model is LMV51.100C2. It is a microprocessor-based burner management system for controlling and monitoring medium and large capacity forced draft burners. The operation and program control of the burner management system are completed by the Siemens operating display (model AZL52.00B1) in the system components; the function of the electronic controller 8 is to display the operating device, actuator, record data and control. The software developer is Siemens AG of Germany, which belongs to the prior art.

[0008] The computer 13 in the temperature control system 6 is equipped with Tianhong Industrial Configuration Software V1.0, which is used to display, record and control the data of each process point. The software developer is Longyan Tianhong Computer Technology Co., Ltd., which was launched in May 2018 and belongs to the prior art; the newly added PLC is developed by Longyan Tianhong Computer Technology Co., Ltd., and the brand of the newly added PLC is Siemens. Its CPU and acquisition control module are Siemens S7-1200 series general products. The newly added PLC software programming is written by Longyan Tianhong Computer Technology Co., Ltd. according to requirements. In short, all the software and hardware with computer programs belong to the prior art that can be purchased from the market.

[0009] The above-mentioned biodiesel distillation production gas furnace heat transfer oil temperature control device has the following technical characteristics and

[0010] Beneficial effects:

[0011] (1) By setting up a new PLC and computer 13, a manual temperature computer control system is formed to achieve precise control of the temperature of the heat transfer oil. The temperature difference of the heat transfer oil can be controlled within plus or minus 0.5°C, meeting the high-precision requirements in biodiesel production and improving the yield of the main product;

[0012] (2) By adding a manual temperature computer control system, operators do not need to manually adjust the temperature of the heat transfer oil on the on-site electronic controller, which reduces the labor intensity of operators and improves production efficiency;

[0013] (3) The computer digital manual operation button can accurately control the temperature of the heat transfer oil, reduce unnecessary energy consumption, and reduce environmental pollution;

[0014] (4) The device is easy and efficient to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The utility model is a schematic diagram of the structure of a heat transfer oil temperature control device for a gas furnace for producing biodiesel distillation.

[0016] Figure 2 yes Figure 1 Schematic diagram of the enlarged structure of the middle distillation tower.

[0017] Figure 3 yes Figure 1 Schematic diagram of the enlarged structure of the medium reboiler.

[0018] Figure 4 yes Figure 1 Enlarged structural diagram of the heat transfer oil temperature control system.

[0019] Figure 5 yes Figure 1 Schematic diagram of the enlarged structure of the medium heat transfer oil furnace.

[0020] Figure symbols: distillation tower 1, reboiler 2, high temperature circulation pump 3, thermal oil furnace circulation pump 4, servo electric gas butterfly valve 5, temperature control system 6, digital display thermometer 7, electronic controller 8, manual high fire button switch 9, manual low fire button switch 10, control state conversion switch 11, external common electric control box 12, computer 13, thermal oil furnace 14, distillation tower crude methyl ester feed inlet a, distillation tower vacuum outlet b, distillation tower biodiesel outlet c, distillation tower reboiler vapor phase inlet d, distillation tower heavy oil outlet e, distillation tower reboiler circulation outlet f, reboiler biodiesel inlet g1, reboiler biodiesel outlet g2, reboiler thermal oil outlet h1, reboiler thermal oil inlet h2, thermal oil furnace burner natural gas inlet i, thermal oil furnace tail gas outlet pipe j, thermal oil furnace thermal oil outlet k, thermal oil furnace thermal oil inlet l, T-temperature, I-display, V-regulating valve, C-control, A-alarm. DETAILED DESCRIPTION

[0021] The specific implementation of the heat transfer oil temperature control device for a gas furnace for producing biodiesel distillation is further described in detail below in conjunction with the accompanying drawings.

[0022] Figure 1-Figure 5 As shown, the utility model of the thermal oil temperature control device for the biodiesel distillation production gas furnace comprises a distillation tower 1, a reboiler 2, a high temperature circulation pump 3, a thermal oil furnace circulation pump 4, a servo electric gas butterfly valve 5, a temperature control system 6, a thermal oil furnace 14 and connecting pipes and valves; the middle of the distillation tower 1 is provided with a distillation tower crude methyl ester feed inlet a, the top is provided with a distillation tower vacuum outlet b, the middle and upper part is provided with a distillation tower biodiesel outlet c, the lower side is provided with a distillation tower reboiler vapor phase inlet d, and the bottom is provided with a steam outlet 150mm away from the center. The distillation tower heavy oil outlet e is provided, and the distillation tower reboiler circulation outlet f is provided at the bottom center; the reboiler 2 is provided with a reboiler biodiesel inlet g1 at the top, a reboiler biodiesel outlet g2 at the bottom, a reboiler heat transfer oil outlet h1 at the upper left side, and a reboiler heat transfer oil inlet h2 at the lower left side; the heat transfer oil furnace 14 is provided with a burner natural gas inlet i at the left center, a heat transfer oil furnace exhaust gas outlet j at the right center, a heat transfer oil furnace heat transfer oil outlet k at the bottom, and a heat transfer oil furnace heat transfer oil outlet at the top. inlet 1; the reboiler circulation outlet f of the distillation tower is connected to the biodiesel inlet g1 of the reboiler after being connected to the high-temperature circulation pump 3, and the biodiesel outlet g2 of the reboiler is connected to the vapor phase inlet d of the reboiler of the distillation tower; the heat transfer oil outlet h1 of the reboiler is connected to the heat transfer oil inlet l of the heat transfer oil furnace, and the heat transfer oil outlet k of the heat transfer oil furnace is connected to the heat transfer oil inlet h2 of the reboiler after being connected to the heat transfer oil furnace circulation pump 4; the temperature control system 6 includes a temperature adjustment servo motor SM, a digital display thermometer 7 with a temperature sensor, an electronic controller 8, an external common electric control box 12, a newly added PLC and a computer 13, the electronic controller 8 includes a manual high fire button switch 9, a manual low fire button switch 10, a control state conversion switch 11, a PLC and a display screen, which are respectively connected to the servo electric gas butterfly valve 5 and the digital display thermometer 7 arranged on the heat transfer oil inlet pipeline of the reboiler through signal lines; the newly added PLC is respectively connected to the computer 13, the manual high fire button switch 9, the manual low fire button switch 10, and the control state conversion switch 11 through signal lines.

[0023] The specific operation process of the utility model of the heat transfer oil temperature control device for the biodiesel distillation production gas furnace is as follows:

[0024] During distillation production, prepare to start production according to the biodiesel distillation operating procedures, notify the boiler workshop to heat up the thermal oil furnace; set the thermal oil temperature to 250±5℃ through the thermal oil furnace burner control table WEST, start the thermal oil heating to heat the crude biodiesel in the reboiler 2; start the temperature control system 6, automatically adjust the size of the natural gas servo electric gas butterfly valve 5, and gradually increase the thermal oil temperature to 250℃ according to the biodiesel distillation production requirements; start the crude biodiesel feed pump according to the temperature of each biodiesel distillation tower The crude biodiesel is pumped to the crude methyl ester feed inlet a of the distillation tower, the crude biodiesel is vaporized and evaporated in the distillation tower 1, and the qualified product flows out from the biodiesel outlet c of the distillation tower, and the liquid phase flows out from the circulation outlet f of the distillation tower reboiler and enters the high-temperature circulation pump 3. After passing through the high-temperature circulation pump 3, the crude biodiesel enters from the biodiesel inlet g1 of the reboiler, and after the crude biodiesel is heated and vaporized in the reboiler 2, it flows out from the biodiesel outlet g2 of the reboiler and enters the vapor phase inlet d of the distillation tower reboiler for re-distillation, and the heavy oil that cannot be re-distilled flows out from the heavy oil outlet e of the distillation tower. When the product starts to be discharged, take samples to observe whether the color of the finished oil is transparent and whether the smell is normal, detect the sulfur content, free glycerol content and heavy oil yield of the finished oil, and refer to the measured data to adjust the gas phase temperature of each tower, and adjust the discharge amount, reflux amount and crude ester feed amount accordingly to ensure that the quality of the finished product meets the indicators; when the production is stable and normal, according to long-term production practice, it is best to control the temperature difference of the heat transfer oil within plus or minus 0.5°C for the production product quality and the main product yield. At this time, the temperature control system 6 is set to manual mode, and the temperature difference of the heat transfer oil inlet of the reboiler 2 is set to be controlled within the limit of plus or minus 0.5°C. The temperature sensor sends a signal to the newly added PLC, and the opening size of the servo electric gas butterfly valve 5 is manually operated on the computer according to the process set temperature, that is, the size of the gas entering the heat transfer oil furnace burner is used to control the temperature of the heat transfer oil furnace, thereby ensuring that the temperature difference of the heat transfer oil inlet of the reboiler 2 is controlled within plus or minus 0.5°C.

[0025] The utility model discloses a heat transfer oil temperature control device for a biodiesel distillation production gas furnace, which accurately controls the temperature of the heat transfer oil, ensures continuous and stable operation of the production, ensures stable product quality, improves the yield of the main product, and reduces energy consumption.

Claims

1. A biodiesel distillation gas furnace heat transfer oil temperature control device, comprising a distillation tower (1), a reboiler (2), a high temperature circulation pump (3), a heat transfer oil furnace circulation pump (4), a servo electric gas butterfly valve (5), a temperature control system (6), a heat transfer oil furnace (14) and connecting pipes and valves; the distillation tower (1) is provided with a distillation tower crude methyl ester feed inlet (a) in the middle, a distillation tower vacuum outlet (b) at the top, a distillation tower biodiesel outlet (c) at the middle and upper part, and a distillation tower reboiler vapor phase inlet (d) at the lower side. ), a distillation tower heavy oil outlet (e) is provided at 150 mm from the center at the bottom, and a distillation tower reboiler circulation outlet (f) is provided at the center of the bottom; the reboiler (2) is provided with a reboiler biodiesel inlet (g1) at the top, a reboiler biodiesel outlet (g2) at the bottom, a reboiler heat transfer oil outlet (h1) at the upper left side, and a reboiler heat transfer oil inlet (h2) at the lower left side; the heat transfer oil furnace (14) is provided with a burner natural gas inlet (i) at the center of the left side, and a heat transfer oil furnace tail gas outlet pipe (h1) at the center of the right side. (j), a heat transfer oil furnace heat transfer oil outlet (k) is provided at the bottom, and a heat transfer oil furnace heat transfer oil inlet (l) is provided at the top; the reboiler circulation outlet (f) of the distillation tower is connected to the reboiler biodiesel inlet (g1) after being connected to the high-temperature circulation pump (3), and the reboiler biodiesel outlet (g2) is connected to the distillation tower reboiler vapor phase inlet (d); the reboiler heat transfer oil outlet (h1) is connected to the heat transfer oil furnace heat transfer oil inlet (l), and the heat transfer oil furnace heat transfer oil outlet (k) is connected to the reboiler heat transfer oil inlet after being connected to the heat transfer oil furnace circulation pump (4). The temperature control system (6) comprises a temperature regulating servo motor SM, a digital thermometer (7) with a temperature sensor, an electronic controller (8), and an external common electric control box (12). The electronic controller (8) comprises a manual high-fire button switch (9), a manual low-fire button switch (10), a control state conversion switch (11), a PLC and a display screen. The electronic controller (8) is respectively connected to a servo electric gas butterfly valve (5) and a digital thermometer (7) provided on the reboiler heat transfer oil inlet pipeline through signal lines. ... and an external common electric control box (12). The temperature control system (6) further comprises a newly added PLC and a computer (13); the newly added PLC is respectively connected to the computer (13), the manual high-fire button switch (9), the manual low-fire button switch (10), and the control state conversion switch (11) via signal lines.

Images