Coal tar processing heat exchange treatment system

Abstract

The utility model discloses a coal tar processing heat exchange treatment system which comprises a tar storage tank, the tar storage tank conveys tar to a tar preheater for preheating through a tar pump, and the preheated tar enters a tar heat exchanger to be subjected to heat exchange cooling with distillate gas escaping from the top of a distillate tower. Tar and distillate gas correspondingly flow through a tube pass and a shell pass of the tar heat exchanger respectively, a channel of the distillate gas in the shell pass is subjected to lateral left-right alternating non-blocking baffling passing through through a plurality of baffle plates, and an anti-blocking heating heating tube is installed on the lower portion of the shell pass. And the heating pipe is arranged at the lower part of the shell pass, so that the discharge resistance can be integrally reduced, the stable discharge of the liquid three-mixed oil is very facilitated, the tower top pressure of the fraction tower is stabilized, the influence of unstable output of the three-mixed oil gas caused by unstable negative pressure is reduced, and a production system is safer and more stable to operate.

Description

Technical Field

[0001] The utility model relates to the field of coal tar processing, in particular to a coal tar processing heat exchange treatment system. Background Art

[0002] In the coal tar deep processing project, the high-temperature coal tar raw material tank is heated by steam, maintaining the tank temperature at 80-90°C. After standing for more than 36 hours, water and coal tar separate due to their different densities. The separated water in the upper portion of tar storage tank 1 is drained to the phenol water tank via a drain level regulating valve. This static heating dehydration reduces the moisture content of the coal tar to 2%-3%. The tar at the bottom of tar storage tank 1, after preliminary dehydration, is pumped by raw tar pump 2 to tar preheater 3, where it is preheated with low-pressure steam. It then passes through tertiary mixed oil steam / raw tar heat exchanger 4, where the tar outlet temperature is controlled at 165-185°C. The tar then enters the dehydration tower for final dehydration (the tar flows through the tubes 5 of the tube side of tar heat exchanger 4, and the tertiary mixed oil steam flows through the shell side 7 of tar heat exchanger 4).

[0003] The ternary mixed oil vapor of the tar heat exchanger 4 comes from the vacuum distillation tower 11. The ternary mixed distillate gas phase escaping from the top pressure of the distillation tower 11 (-50 to -70 kPa) passes through the ternary mixed oil vapor / raw tar heat exchanger 4 and then enters the ternary mixed oil vapor cooler for cooling.

[0004] The three-mixed fraction / tar heat exchanger 4 is a shell and tube heat exchanger, the medium of the tube side 5 is tar, the medium of the shell side 7 is three-mixed oil and gas, and the baffle 6 of the shell side 7 is arranged with upper and lower notches (such as Figure 4 As shown in the figure, upper and lower baffle channels are formed. During use, it was found that the three-mixed distillate gas phase escaping from the top of the distillation tower 11 was cooled down after heat exchange with tar in this heat exchanger, and was in the form of gas-liquid coexistence in the shell side 7 of the heat exchanger. Since the baffle of the heat exchanger is an upper and lower flow arrangement structure, it will cause interception and blockage, and the three-mixed oil (gas-liquid) will not be discharged smoothly, resulting in unstable negative pressure at the top of the distillation tower 11, limited output, and affecting the safe and stable operation of the production system. Utility Model Content

[0005] In order to solve the above problems, the utility model provides a coal tar processing heat exchange treatment system.

[0006] The utility model is realized through the following technical solutions:

[0007] A coal tar processing and heat exchange treatment system includes a tar storage tank, which transports tar from the tar storage tank to a tar preheater for preheating via a tar pump. The preheated tar enters the tar heat exchanger for heat exchange and cooling with distillate gas escaping from the top of a distillation tower. Tar and distillate gas flow through the tube side and shell side of the tar heat exchanger respectively. The distillate gas channel in the shell side is deflected alternately and unobstructed to the left and right sides by a plurality of baffles. A heating pipe for anti-blocking heating is installed at the bottom of the shell side.

[0008] Further optionally, multiple baffles are arranged inside the shell side of the tar heat exchanger to support and fix the tube side, and flow notches are alternately provided on the sides of adjacent baffles to form side unobstructed flow channels between the flow notches and the shell side.

[0009] Further optionally, the heating tube is arranged at the lower end of the shell side and is arranged horizontally, and the heating tube is arranged along the bending channel between the baffle and the flow notch to form a bent tube.

[0010] Further optionally, the inlet of the heating tube is arranged at the outlet end of the shell side.

[0011] Further optionally, the shell side outlet of the tar heat exchanger is connected to a vacuum pump through a pipeline and transported to an oil-gas cooler.

[0012] Further optionally, the outlet of the shell side is connected to the dehydration tower through a pipeline.

[0013] Further optionally, control valves are installed on the inlet and outlet of the heating pipe and each connecting pipeline.

[0014] Compared with the existing technology, the beneficial effects of the present invention are as follows: the present invention changes the shell-side baffle structure of the heat exchanger into a left-right bent flow structure, and arranges a heating pipe at the lower part of the shell side, which can reduce the discharge resistance as a whole, is very conducive to the smooth discharge of liquid tri-mixed oil, stabilizes the top pressure of the distillation tower, reduces the impact of unstable tri-mixed oil and gas output caused by unstable negative pressure, and makes the production system run more safely and stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the utility model system;

[0016] Figure 2 This is a schematic diagram of the internal structure of the shell side of this practical tar heat exchanger;

[0017] Figure 3 yes Figure 3 A top view of

[0018] Figure 4 It is a schematic diagram of the prior art of this utility;

[0019] In the figure: tar storage tank 1, tar pump 2, tar preheater 3, tar heat exchanger 4, tube side 5, baffle 6, shell side 7, flow gap 8, heating tube 9, bent tube 10, vacuum pump 11, distillation tower 12. DETAILED DESCRIPTION

[0020] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0021] like Figure 1 As shown, a coal tar processing heat exchange treatment system includes a tar storage tank 1, which transports tar to a tar preheater 3 for preheating through a tar pump 2. The preheated tar enters a tar heat exchanger 4 for heat exchange and cooling with the distillate gas escaping from the top of a distillation tower 12. The tube side 5 and the shell side 7 of the tar heat exchanger 4 flow through the tar and the distillate gas respectively. The channel of the distillate gas in the shell side 7 is deflected alternately on the left and right sides without obstruction by a plurality of deflectors 6. A heating pipe 9 for anti-blocking heating is installed at the bottom of the shell side 7.

[0022] like Figure 2 As shown, multiple baffles 6 are arranged inside the shell side 7 of the tar heat exchanger 4 to support and fix the tube side 5. Flow notches 8 are alternately provided on the left and right sides of adjacent baffles 6. Side unobstructed flow channels are formed between the flow notches 8 and the shell side 7. Compared with the obstruction and interception effect of the original upper and lower bending channels, the left and right bending channels have no interception and blocking effect, which greatly reduces the discharge resistance for the liquid three-mixed oil, is very beneficial to the smooth discharge of the liquid three-mixed oil, and stabilizes the top pressure of the distillate tower.

[0023] like Figure 3 As shown, the heating pipe 9 is arranged at the lower end of the shell side 7 and is arranged horizontally. The heating pipe 9 is arranged along the bending channel between the baffle 6 and the flow notch 8 to form a bent pipe 10. This arrangement can completely heat the left and right bending channels, increase the temperature of the condensation area at the lower part of the shell side 7, and thus improve the fluidity of the liquid three-mixed oil.

[0024] like Figure 1 、 3 As shown, the inlet of the heating pipe 9 is arranged at the outlet end of the shell side 7, and the lowest temperature point of the outlet end of the shell side 7 is first heated to improve the outflow of the liquid tri-mixed oil.

[0025] The shell side 7 outlet of the tar heat exchanger 4 is connected to the vacuum pump 11 through a pipeline and transported to the oil and gas cooler.

[0026] The outlet of the shell side 7 is connected to the dehydration tower through a pipeline, and control valves are installed on the inlet and outlet of the heating pipe 9 and each connecting pipeline.

[0027] The implementation principle of a coal tar processing heat exchange treatment system in the embodiment of the present application is:

[0028] After being preheated by the tar preheater 3, the tar enters the tube side 5 of the tar heat exchanger 4, and exchanges heat with the three-mixed distillate gas phase escaping from the top of the distillation tower 11 at a pressure of -50 to -70 kPa, and enters the shell side 7 of the tar heat exchanger 4. When the three-mixed distillate gas passes through the shell side 7 of the tar heat exchanger 4, it passes through the flow notches 8 on the side of the baffle 6 in sequence to form a horizontally curved channel. The resistance is greatly reduced when passing through this horizontal curved channel, which is very conducive to the smooth discharge of the condensed liquid three-mixed oil, stabilizes the pressure at the top of the distillation tower, reduces the impact of unstable negative pressure on the unstable output of the three-mixed oil and gas, and makes the production system operate more safely and stably.

[0029] At the same time, heating pipes 9 are arranged at the lower part of the shell side 7 of the tar heat exchanger 4 according to the left and right bending channels of the baffles 6. High-temperature steam enters from the end of the shell side 7 and quickly heats the end of the shell side 7 (the end is the last area of ​​the three-mixed oil and gas heat exchange, and the temperature in this area is relatively low, so it is most likely to accumulate liquid three-mixed oil), thereby increasing the temperature of the liquid three-mixed oil. The higher the temperature of the liquid three-mixed oil, the greater its fluidity, thereby preventing the liquid three-mixed oil from accumulating at the end of the shell side 7, ensuring the fluidity of the liquid three-mixed oil, and improving the stability of the liquid three-mixed oil discharge.

[0030] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements are intended to fall within the scope of the present invention. The scope of protection claimed in this invention is defined by the appended claims and their equivalents.

Claims

1. A coal tar processing heat exchange treatment system, comprising a tar storage tank (1), wherein the tar storage tank (1) transports tar to a tar preheater (3) for preheating via a tar pump (2), and the preheated tar enters a tar heat exchanger (4) for heat exchange cooling with distillate gas escaping from the top of a distillation tower (12), characterized in that: The tube side (5) and shell side (7) of the tar heat exchanger (4) respectively flow through tar and distillate gas. The distillate gas channel in the shell side (7) is deflected alternately and unobstructedly on the left and right sides by a plurality of baffles (6). A heating pipe (9) for anti-blocking heating is installed at the bottom of the shell side (7).

2. A coal tar processing heat exchange treatment system according to claim 1, characterized in that: A plurality of baffles (6) are arranged inside the shell side (7) of the tar heat exchanger (4) to support and fix the tube side (5), and flow notches (8) are alternately provided on the left and right sides of adjacent baffles (6), forming a side unobstructed flow channel between the flow notches (8) and the shell side (7).

3. The coal tar processing heat exchange treatment system according to claim 1, characterized in that: The heating tube (9) is arranged at the lower end of the shell side (7) and is arranged transversely. The heating tube (9) is arranged along the bending channel between the baffle (6) and the flow notch (8) to form a bent tube (10).

4. A coal tar processing heat exchange treatment system according to claim 3, characterized in that: The inlet of the heating tube (9) is arranged at the outlet end of the shell side (7).

5. The coal tar processing heat exchange treatment system according to claim 2, characterized in that: The shell side (7) outlet of the tar heat exchanger (4) is connected to a vacuum pump (11) through a pipeline and transported to an oil-gas cooler.

6. The coal tar processing heat exchange treatment system according to claim 5, characterized in that: The outlet of the shell side (7) is connected to the dehydration tower through a pipeline.

7. The coal tar processing heat exchange treatment system according to claim 4, characterized in that: Control valves are installed on the inlet and outlet of the heating pipe (9) and each connecting pipeline.

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