Bioheavy oil cooling device for high-vacuum reduced pressure distillation of biodiesel

Abstract

The utility model discloses a biological heavy oil cooling device for high-vacuum reduced pressure distillation of biodiesel. A distribution plate is arranged in a bottom sealing head of a tubular cooler; after the hot biological heavy oil pipe is connected with an inlet thermometer and a ball valve, one path is connected with a bottom feeding hole of the cooler, and the other path is connected with an emptying valve and an emptying pipe; the water inlet pipe is connected with a lower cooling water inlet of the cooler after being connected with a pneumatic control valve, a thermometer and a flowmeter; the cooler is provided with a drain valve and an exhaust valve; the upper half part of the cooler is provided with high-position, middle-position and low-position water outlet pipes with valves; the other ends of the three water outlet pipes are connected with a water outlet header pipe with a thermometer; the cooling areas of the coolers corresponding to the high-position, middle-position and low-position water outlet pipes are large, middle and small; a discharge hole in the top of the cooler is connected with an outlet valve, a thermometer, a check valve, a flow meter and an underground biological heavy oil tank pipe with a valve after being connected with a biological heavy oil outlet pipe; and the DCS system is connected with the pneumatic control valve and the biological heavy oil outlet thermometer through signal lines. The device is convenient and efficient to operate, and the temperature of cooled biological heavy oil is stably controlled.

Description

Technical Field

[0001] The utility model relates to the technical field of auxiliary devices for production of organic chemical products biodiesel, in particular to a biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device. Background Art

[0002] Industrial production of biodiesel generally uses waste animal and vegetable oils as raw materials. After purification, the raw oil is subjected to methyl esterification and ester exchange reaction at a specific temperature to produce crude biodiesel, and then high-vacuum continuous reduced pressure distillation is used to obtain finished biodiesel.

[0003] When crude biodiesel is subjected to high vacuum decompression distillation, the absolute pressure in the distillation tower is generally controlled within the range of 200-400Pa. After the material is heated to a specific temperature, it is distilled out through multiple series distillation towers to produce qualified biodiesel. The qualified biodiesel of each fraction is discharged from the upper middle part of the distillation tower, and the bottom discharge of the last distillation tower is bio-heavy oil. Under normal circumstances, the temperature of the bio-heavy oil coming out of the bottom of the tower is relatively high, and a cooler is generally used for effective cooling. When installing the distillation tower, the bottom discharge port of the tower is required to be at a certain height from the ground to ensure that the outlet pressure of the bio-heavy oil pipeline on the ground is greater than 1 standard atmospheric pressure; in order to reduce the resistance of the bio-heavy oil discharge, the bio-heavy oil cooling adopts a tube cooler, which is installed vertically on the ground bracket. The cooled bio-heavy oil flows into the underground bio-heavy oil tank by gravity, and then is pumped to the bio-heavy oil storage tank by a high-temperature gear pump.

[0004] The heat exchange area of ​​the existing bio-heavy oil cooling device tube cooler is relatively fixed, and the water inlet valve is manually adjusted, which has the following defects:

[0005] (1) When the bio-heavy oil discharge is large, even if the cooling water valve is fully opened, it is difficult for the bio-heavy oil to drop to the target temperature. The excessively high temperature causes carbon scale to form easily in the underground bio-heavy oil tank and the pipeline to the bio-heavy oil storage tank;

[0006] (2) When the amount of bio-heavy oil in the distillation tower is large, the temperature of the bio-heavy oil after cooling is too high, resulting in a large amount of gas exhaled from the underground bio-heavy oil tank exhaust pipe, and a strong oil odor that affects the surrounding environment.

[0007] (3) When the bio-heavy oil discharge is small, even if the cooling water valve is closed, the bio-heavy oil temperature will drop too much. The too low temperature will cause the bio-heavy oil discharge from the distillation tower to be blocked, which can easily cause the distillation tower to be full and affect the normal distillation.

[0008] (4) Since the cooled bio-heavy oil is generally returned to the fuel oil boiler in the production line for use, the bio-heavy oil with excessive temperature fluctuations will cause its viscosity to change greatly, affecting the normal use of the fuel oil boiler.

[0009] (5) The water inlet valve of the bio-heavy oil cooling device is manually adjusted and difficult to control. Summary of the invention

[0010] The utility model aims to provide a biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device with low manufacturing and maintenance costs, convenient and efficient operation, safe and reliable production, and stable temperature control of the bio-heavy oil after cooling, so as to solve the problems that the heat exchange area of ​​the tube cooler of the above-mentioned prior art bio-heavy oil cooling device is relatively fixed and the water inlet valve is manually adjusted.

[0011] To achieve the above purpose, the utility model biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device comprises a tube cooler 10 and a DCS automatic control system; a distribution plate is arranged in the bottom head of the tube cooler 10 to evenly distribute the bio-heavy oil after entering the cooler to prevent the bio-heavy oil from short-circuiting; the hot bio-heavy oil pipe 5 is divided into two paths after connecting the bio-heavy oil inlet thermometer 6 and the high-temperature ball valve 7, one path is connected to the bottom feed port of the tube cooler 10, and the other path is connected to the bio-heavy oil vent valve 8 and the bio-heavy oil vent pipe 9; the water inlet pipe 1 is connected to the cooling water inlet of the lower part of the tube cooler 10 after connecting the pneumatic regulating valve 2, the water inlet thermometer 3 and the electromagnetic flowmeter 4; the lower part of the tube cooler 10 is provided with a drain valve 26, and the upper part is provided with an exhaust valve 27; the upper half of the tube cooler 10 is provided with high-level water outlet valves at different heights. The high-position water outlet pipe 12 of the valve 17, the middle water outlet pipe 13 with the middle water outlet valve 16 and the low-position water outlet pipe 14 with the low-position water outlet valve 15, the other ends of the three water outlet pipes are connected to the water outlet main pipe 19 with the water outlet thermometer 18; the cooling area of ​​the cooler corresponding to the high-position water outlet pipe 12 is larger than that of the middle water outlet pipe 13, and the cooling area of ​​the cooler corresponding to the low-position water outlet pipe 14 is smaller than that of the middle water outlet pipe 13; the top discharge port of the tube cooler 10 is connected to the bio-heavy oil outlet valve 20, the bio-heavy oil outlet thermometer 21, the lifting bio-heavy oil check valve 22, the high-temperature mass flowmeter 23, the underground bio-heavy oil tank valve 24 and the underground bio-heavy oil tank pipe 25 in sequence after being connected to the bio-heavy oil outlet pipe 11; the DCS automatic control system is connected to the pneumatic regulating valve 2 and the bio-heavy oil outlet thermometer 21 with signal lines respectively.

[0012] The above-mentioned biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device adopts a DCS automatic control system to control the temperature of the cooled bio-heavy oil. The DCS automatic control system automatically controls the opening of the cooling water pneumatic regulating valve 2 according to the temperature displayed by the bio-heavy oil outlet thermometer 21, so as to control the bio-heavy oil outlet temperature within a set range.

[0013] The host computer of the above-mentioned DCS automatic control system is equipped with Tianhong Industrial Configuration Software V1.0. The function of this software system is to display, record and control the data of each process point. The software developer is Longyan Tianhong Computer Technology Co., Ltd., and the software was launched in May 2018; the PLC used in the DCS automatic control system is a Siemens brand, and the CPU and acquisition control module of the PLC system are Siemens' S7-1200 series general products. The PLC software programming is written by Longyan Tianhong Computer Technology Co., Ltd. according to requirements; all software and hardware with computer programs are existing technologies that can be purchased on the market.

[0014] The biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device of the above structure has the following technical characteristics and beneficial effects:

[0015] (1) The heat exchange area can be switched flexibly among large, medium and small groups. Combined with the DCS automatic control system, the water inlet of the cooler can be automatically adjusted according to the temperature of the bio-heavy oil after cooling to meet the temperature requirements of the fuel oil boiler for the bio-heavy oil.

[0016] (2) The discharge volume, temperature and viscosity of bio-heavy oil are relatively stable, avoiding the phenomenon of tower fullness caused by poor discharge due to low temperature or environmental problems such as carbon fouling in pipelines and strong odor caused by high temperature.

[0017] (3) The device has a simple structure and can meet the different working conditions of large, medium and small bio-heavy oil discharge from the distillation tower. The outlet temperature of the bio-heavy oil after cooling is automatically controlled by DCS, which is simple to operate, convenient and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of a biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device of the utility model.

[0019] Figure numerals: water inlet pipe 1, pneumatic regulating valve 2, water inlet thermometer 3, electromagnetic flowmeter 4, hot bio-heavy oil pipe 5, bio-heavy oil inlet thermometer 6, high-temperature ball valve 7, bio-heavy oil vent valve 8, bio-heavy oil vent pipe 9, tube cooler 10, bio-heavy oil outlet pipe 11, high-level water outlet pipe 12, middle water outlet pipe 13, low-level water outlet pipe 14, low-level water outlet valve 15, middle water outlet valve 16, high-level water outlet valve 17, water outlet thermometer 18, water outlet main pipe 19, bio-heavy oil outlet valve 20, bio-heavy oil outlet thermometer 21, lifting bio-heavy oil check valve 22, high-temperature mass flowmeter 23, valve for going to underground bio-heavy oil tank 24, bio-heavy oil tank pipe for going to underground 25, drain valve 26, exhaust valve 27. DETAILED DESCRIPTION

[0020] The specific implementation of the biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device of the utility model is further described in detail below in conjunction with the accompanying drawings.

[0021] Figure 1 As shown, the utility model biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device comprises a tube cooler 10 and a DCS automatic control system; a distribution plate is arranged in the bottom head of the tube cooler 10 to evenly distribute the bio-heavy oil after entering the cooler to prevent the bio-heavy oil from short-circuiting; the hot bio-heavy oil pipe 5 is divided into two paths after connecting the bio-heavy oil inlet thermometer 6 and the high-temperature ball valve 7, one path is connected to the bottom feed port of the tube cooler 10, and the other path is connected to the bio-heavy oil vent valve 8 and the bio-heavy oil vent pipe 9; the water inlet pipe 1 is connected to the cooling water inlet of the lower part of the tube cooler 10 after connecting the pneumatic regulating valve 2, the water inlet thermometer 3 and the electromagnetic flowmeter 4; the lower part of the tube cooler 10 is provided with a drain valve 26, and the upper part is provided with an exhaust valve 27; the upper half of the tube cooler 10 is provided with a high-level water outlet valve 1 at different heights. 7, a high-position water outlet pipe 12, an intermediate water outlet pipe 13 with an intermediate water outlet valve 16, and a low-position water outlet pipe 14 with a low-position water outlet valve 15, and the other ends of the three water outlet pipes are connected to a water outlet main pipe 19 with an outlet water thermometer 18; the cooling area of ​​the cooler corresponding to the high-position water outlet pipe 12 is larger than that of the intermediate water outlet pipe 13, and the cooling area of ​​the cooler corresponding to the low-position water outlet pipe 14 is smaller than that of the intermediate water outlet pipe 13; the top discharge port of the tube cooler 10 is connected to the bio-heavy oil outlet pipe 11 and then connected to the bio-heavy oil outlet valve 20, the bio-heavy oil outlet thermometer 21, the lifting bio-heavy oil check valve 22, the high-temperature mass flowmeter 23, the underground bio-heavy oil tank valve 24 and the underground bio-heavy oil tank pipe 25; the DCS automatic control system is connected to the pneumatic regulating valve 2 and the bio-heavy oil outlet thermometer 21 with signal lines respectively.

[0022] The pneumatic control valve 2 for cooling water inlet is connected to the control system with a shielded cable of RVVP4*1, wherein the two core wires as the control signal of the control valve are connected to the analog output AO module, and the other two core wires as the feedback signal of the control valve are connected to the analog input AI module. The analog output signal of the control system controls the opening size of the pneumatic control valve 2, and the feedback signal of the opening of the control valve enters the analog input signal of the control system.

[0023] The above-mentioned bio-heavy oil outlet thermometer 21 is connected to the analog input AI module of the control system by a shielded cable of RVVP3*1. The control system automatically adjusts the opening of the cooling water pneumatic regulating valve 2 to make the outlet bio-heavy oil temperature reach the set temperature.

[0024] The above-mentioned pneumatic control valve 2 is a product produced by Shanghai Juliang Valve Group, the product model is ZJHP-16P, the specifications are DN40, PN16, the valve body material is stainless steel, the valve core material is stainless steel, the packing is polytetrafluoroethylene, with valve position feedback, and equipped with HEP positioning and pressure reducer.

[0025] The above-mentioned biological heavy oil outlet thermometer 21 is a Pt100 thermal resistor, a three-wire system, connected with DN25 and PN16 flanges, with a thermometer diameter of 16 mm and an insertion depth of 200 mm, and is a mature product in the market.

[0026] The operation of the biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device of the utility model is as follows:

[0027] (1) When the distillation tower is started, the drain valve 26, the vent valve 27, the low-level water outlet valve 15 and the high-level water outlet valve 17 of the tube cooler 10 are closed, the intermediate water outlet valve 16 is opened, and the pneumatic regulating valve 2 is manually opened to allow the cooling water to fill the shell side of the tube cooler 10, and then flow from the intermediate water outlet pipe 13 to the water outlet main pipe 19, and then flow to the return water collection tank by gravity.

[0028] (2) Close the bio-heavy oil vent valve 8 and the valve to the underground bio-heavy oil tank 24, and open the high-temperature ball valve 7 and the bio-heavy oil outlet valve 20.

[0029] (3) When the distillation tower operates normally and discharges qualified biodiesel, the valve 24 to the underground bio-heavy oil tank is opened, and the high-temperature bio-heavy oil from the bottom of the last distillation tower passes through the hot bio-heavy oil pipe 5 and enters the bottom of the tube cooler 10. The distribution plate arranged in the bottom head can evenly distribute the bio-heavy oil to prevent the bio-heavy oil from short-circuiting. The bio-heavy oil flows through the heat exchange tube. The cooled bio-heavy oil flows from the bio-heavy oil outlet pipe 11 through the bio-heavy oil outlet valve 20, the bio-heavy oil outlet thermometer 21, the lifting bio-heavy oil check valve 22, the high-temperature mass flowmeter 23, the valve 24 to the underground bio-heavy oil tank and the underground bio-heavy oil tank pipe 25 to the underground bio-heavy oil tank.

[0030] (4) When the bio-heavy oil is discharged continuously and normally, the pneumatic regulating valve 2 of the cooling water is switched to the automatic position, and the pneumatic regulating valve 2 will automatically adjust according to the displayed temperature of the bio-heavy oil outlet thermometer 21.

[0031] (5) When the bio-heavy oil flow rate out of the distillation tower is particularly large, the low-level water outlet valve 15 and the middle-level water outlet valve 16 of the cooler can be closed, and the high-level water outlet valve 17 of the cooler can be opened to use a large cooling area to cool the bio-heavy oil; when the bio-heavy oil flow rate out of the distillation tower is particularly small, the middle-level water outlet valve 16 and the high-level water outlet valve 17 of the cooler can be closed, and the low-level water outlet valve 15 of the cooler can be opened to use a small cooling area to cool the bio-heavy oil; when the bio-heavy oil flow rate out of the distillation tower is within a normal range, the high-level water outlet valve 17 of the cooler and the valve 15 of the low-level water outlet can be closed, and the middle-level water outlet valve 16 of the cooler can be opened to use a normal cooling area to cool the bio-heavy oil; in this way, the problem that the bio-heavy oil discharge flow rate of the distillation tower fluctuates greatly and affects the cooling temperature of the bio-heavy oil can be completely solved.

[0032] (6) The low-position water outlet valve 15, the middle water outlet valve 16 and the high-position water outlet valve 17 can be manual valves because they are not frequently opened and closed.

Claims

1. A biodiesel high vacuum reduced pressure distillation bio-heavy oil cooling device, characterized by: It comprises a tube cooler (10) and a DCS automatic control system; a distribution plate is arranged in the bottom end cap of the tube cooler (10) to evenly distribute the bio-heavy oil after entering the cooler to prevent the bio-heavy oil from short-circuiting; a hot bio-heavy oil pipe (5) is divided into two paths after being connected to a bio-heavy oil inlet thermometer (6) and a high-temperature ball valve (7), one path being connected to the bottom feed port of the tube cooler (10), and the other path being connected to a bio-heavy oil vent valve (8) and a bio-heavy oil vent pipe (9); a water inlet pipe (1) is connected to a cooling water inlet at the bottom of the tube cooler (10) after being connected to a pneumatic regulating valve (2), a water inlet thermometer (3) and an electromagnetic flowmeter (4); a drain valve (26) is arranged at the bottom of the tube cooler (10), and an exhaust valve (27) is arranged at the top; a high-position water outlet pipe (12) with a high-position water outlet valve (17), a middle-position water outlet pipe (13) with a middle-position water outlet valve (14) and a cooling water outlet pipe (15) are arranged at different heights on the upper half of the tube cooler (10). The middle water outlet pipe (13) of the water valve (16) and the low-position water outlet pipe (14) with the low-position water outlet valve (15), the other ends of the three water outlet pipes are connected to the water outlet main pipe (19) with the water outlet thermometer (18); the cooling area of ​​the cooler corresponding to the high-position water outlet pipe (12) is larger than that of the middle water outlet pipe (13), and the cooling area of ​​the cooler corresponding to the low-position water outlet pipe (14) is smaller than that of the middle water outlet pipe (13); the top discharge port of the tube cooler (10) is connected to the bio-heavy oil outlet pipe (11) and then connected to the bio-heavy oil outlet valve (20), the bio-heavy oil outlet thermometer (21), the lifting bio-heavy oil check valve (22), the high-temperature mass flowmeter (23), the underground bio-heavy oil tank valve (24) and the underground bio-heavy oil tank pipe (25); the DCS automatic control system is connected to the pneumatic regulating valve (2) and the bio-heavy oil outlet thermometer (21) by signal lines.

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