Heater for heating by using heptane in production of vinyl chloride by calcium carbide method

Abstract

The utility model discloses a heptane heating preheater for producing vinyl chloride by using a calcium carbide method, and relates to the technical field of chemical process equipment. A heptane heating preheater for production of vinyl chloride by a calcium carbide method is characterized in that the top of the preheater is connected with a mixed gas inlet pipe, the bottom of the preheater is connected with a mixed gas outlet pipe, the mixed gas outlet pipe is connected with a converter, the heptane heating preheater comprises a heptane heater and a heptane storage tank, the heptane heater is connected with a heptane circulating pump, and the heptane circulating pump is connected with the converter. The heptane circulating pump is connected with one side of the preheater through a heptane inlet pipe, the other side of the preheater is connected with the heptane storage tank through a heptane outlet pipe, and the heptane storage tank is communicated with the heptane heater. Heated heptane is conveyed into the preheater and exchanges heat with mixed gas, the heat exchange process is safe and reliable, the heptane cannot react with the mixed gas after leakage, and the problem that the service life of follow-up process equipment is affected by inner leakage of the preheater due to the fact that the preheater used in a traditional process uses hot water for heating is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical process equipment, in particular to a preheater heated by heptane in the production of vinyl chloride by the calcium carbide process. Background Art

[0002] In the current process of producing vinyl chloride by the calcium carbide method, acetylene and hydrogen chloride are mixed according to the ratio, deep-cooled and dehydrated, and then preheated and enter the converter for reaction.

[0003] To ensure the conversion temperature, acetylene and hydrogen chloride are cryogenically cooled to remove water, mixed to form a mixed gas, and then enter the preheater for heating. The outlet temperature of the preheater is required to be ≥85℃.

[0004] The preheater used in the traditional process is heated by hot water. In the event of internal leakage in the preheater, the hot water will react with the hydrogen chloride in the mixed gas to generate hydrochloric acid. The acid-containing mixed gas will enter the catalyst in the converter tubes, which will not only easily cause the catalyst in the converter to agglomerate, affecting the converter ventilation volume and conversion efficiency, but will also lead to corrosion of the subsequent carbon steel equipment in the conversion system, causing damage to the equipment and affecting the continuous production of the device. Utility Model Content

[0005] In response to the above technical problems, the utility model provides a preheater using heptane heating for the production of vinyl chloride by the calcium carbide process, which is used to solve the problem that when the mixed gas enters the preheater for heating, the hot water in the preheater leaks and reacts with the hydrogen chloride in the mixed gas, affecting the service life of subsequent process equipment.

[0006] In order to achieve the above-mentioned purpose, the technical solution of the present utility model is as follows:

[0007] A preheater heated by heptane is used in the production of vinyl chloride using the calcium carbide process. The top of the preheater is connected to a mixed gas inlet pipe, the bottom of the preheater is connected to a mixed gas outlet pipe, the mixed gas outlet pipe is connected to a converter, and the preheater includes a heptane heater and a heptane storage tank. The heptane heater is connected to a heptane circulation pump, which is connected to one side of the preheater through a heptane inlet pipe, and the other side of the preheater is connected to the heptane storage tank through a heptane outlet pipe. The heptane storage tank is connected to the heptane heater.

[0008] Furthermore, an inlet regulating valve is installed on the heptane inlet pipe, and an outlet thermometer is installed on the heptane outlet pipe. The inlet regulating valve and the outlet thermometer are interlocked through a DCS controller, and the DCS controller is also interlocked with the heptane heater.

[0009] Furthermore, a drain pipe is installed on the mixed gas outlet pipe, and a drain valve is installed on the drain pipe.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention transports the heated heptane into the preheater to exchange heat with the mixed gas, the heat exchange process is safe and reliable, and leakage will not react with the mixed gas, thereby avoiding the problem that the preheater used in the traditional process uses hot water for heating, and internal leakage in the preheater affects the service life of subsequent process equipment, and the heptane after heat exchange enters the heptane storage tank for recycling, thereby improving economic benefits; the DCS controller interlocks the control of the inlet regulating valve, the outlet thermometer and the heptane heater to realize automatic adjustment of the preheater temperature to ensure that the mixed gas output by the preheater meets the use requirements of the next process. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural diagram of the utility model;

[0012] In the picture:

[0013] 1. Preheater; 2. Heptane inlet pipe; 3. Heptane outlet pipe; 4. Inlet regulating valve; 5. Outlet thermometer; 6. DCS controller; 7. Mixed gas inlet pipe; 8. Mixed gas outlet pipe; 9. Drain valve; 10. Heptane heater; 11. Heptane circulation pump; 12. Heptane storage tank; 13. Drain pipe. DETAILED DESCRIPTION

[0014] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are merely illustrative and are not intended to limit the scope of the present invention. Furthermore, descriptions of known structures and technologies are omitted in the following description to avoid unnecessary confusion regarding the concepts of the present invention.

[0015] A preheater for producing vinyl chloride using a calcium carbide process and using heptane for heating is disclosed. The top of the preheater 1 is connected to a mixed gas inlet pipe 7, the bottom of the preheater 1 is connected to a mixed gas outlet pipe 8, the mixed gas outlet pipe 8 is connected to a converter, and the preheater 10 includes a heptane heater 10 and a heptane storage tank 12. The heptane heater 10 is connected to a heptane circulation pump 11. The heptane circulation pump 11 is connected to one side of the preheater 1 through a heptane inlet pipe 2, and the other side of the preheater 1 is connected to the heptane storage tank 12 through a heptane outlet pipe 3. The heptane storage tank 12 is in communication with the heptane heater 10. Before the system is operated, steam is used to heat the heptane heater 10. The hot heptane is transported to the preheater 1 through the heptane inlet pipe 2 by the heptane circulation pump 11, and the heated heptane is transported to the preheater 1 for heat exchange with the mixed gas. The heat exchange process is safe and reliable, and leakage will not react with the mixed gas. The heptane after heat exchange enters the heptane storage tank 12 for recycling, thereby improving economic benefits.

[0016] An inlet regulating valve 4 is installed on the heptane inlet pipe 2, and an outlet thermometer 5 is installed on the heptane outlet pipe 3. The inlet regulating valve 4 and the outlet thermometer 5 are interlocked through a DCS controller 6. The DCS controller 6 is also interlocked with the heptane heater 10 to achieve automatic temperature adjustment of the preheater 1 to ensure that the mixed gas output by the preheater 1 meets the use requirements of the next process.

[0017] A drain pipe 13 is also installed on the mixed gas outlet pipe 8 , and a drain valve 9 is installed on the drain pipe 13 to facilitate internal leakage inspection of the preheater 1 .

[0018] When using:

[0019] 1. Open all valves on the heptane inlet pipe 2, close the valve on the heptane outlet pipe 3, and open the shell-side exhaust valve of the preheater 1 to exhaust;

[0020] 2. Start the heptane circulation pump 11, open the inlet regulating valve 4 halfway, observe the exhaust situation of the shell side exhaust valve of the preheater 1, and when the exhaust changes from the initial exhaust to the full heptane discharge in the pipeline, open the valve on the heptane outlet pipeline of the preheater 1;

[0021] 3. After the mixed gas inlet pipe 7 is ventilated, the temperature indicated by the outlet thermometer 5 on the mixed gas outlet pipe 8 is observed to see if it meets the target range. If the mixed gas temperature meets the target, it is transported to the converter for the next process. If the mixed gas temperature does not meet the target, the DCS controller 6 controls the inlet regulating valve 4 to close and adjusts the heating temperature of the heptane heater 10 to achieve automatic temperature adjustment of the preheater 1 to ensure that the mixed gas output from the preheater 1 meets the requirements of the next process.

[0022] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A preheater for producing vinyl chloride by the calcium carbide process using heptane heating, wherein the top of the preheater (1) is connected to a mixed gas inlet pipe (7), the bottom of the preheater (1) is connected to a mixed gas outlet pipe (8), and the mixed gas outlet pipe (8) is connected to a converter, characterized in that: The invention comprises a heptane heater (10) and a heptane storage tank (12), wherein the heptane heater (10) is connected to a heptane circulation pump (11), the heptane circulation pump (11) is connected to one side of a preheater (1) through a heptane inlet pipe (2), the other side of the preheater (1) is connected to the heptane storage tank (12) through a heptane outlet pipe (3), and the heptane storage tank (12) is connected to the heptane heater (10).

2. The preheater for producing vinyl chloride by the calcium carbide process using heptane heating according to claim 1, characterized in that: The heptane inlet pipe (2) is provided with an inlet regulating valve (4), and the heptane outlet pipe (3) is provided with an outlet thermometer (5). The inlet regulating valve (4) and the outlet thermometer (5) are interlocked via a DCS controller (6), and the DCS controller (6) is also interlocked with the heptane heater (10).

3. The preheater for producing vinyl chloride by the calcium carbide process using heptane heating according to claim 2, characterized in that: A drain pipe (13) is also installed on the mixed gas outlet pipe (8), and a drain valve (9) is installed on the drain pipe (13).

Images