Chlorination reactor feeding system for preparing methane chloride by liquid phase method
By heating hydrogen chloride to 95°C in a hydrogen chloride heater with low pressure steam and mixing it with methanol, the problem of gaseous methanol condensation is solved, and the effective utilization of raw materials and the improvement of reaction yield is achieved.
Patent Information
- Application Number
- CN202422705143.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-06
- Publication Date
- 2025-08-29
- Estimated Expiration
- 2034-11-06
AI Technical Summary
When methanol reacts with hydrogen chloride to prepare monochloromethane, gaseous methanol and low-temperature hydrogen chloride are mixed and condensed, resulting in waste of raw materials and reduced reaction yield.
Before hydrogen chloride enters the chlorination reactor, heats to 95°C through a hydrogen chloride heater using low-pressure steam and mixes it with methanol to avoid condensation of gaseous methanol and use a temperature control system to ensure the stable temperature of hydrogen chloride.
Reduce waste of raw materials, improve reaction yield, and improve the efficiency of preparing monochloromethane.
Smart Images
Figure CN223276234U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of monochloromethane production, in particular to a feeding system of a chlorination reactor for preparing monochloromethane by a liquid phase method. Background Art
[0002] In the production of methyl chloride by chlorination reaction of methanol and hydrogen chloride in zinc chloride solution, methanol and hydrogen chloride react in zinc chloride solution, and the crude product is washed with water, dried, distilled and other processes to obtain methyl chloride product. The specific process flow is as follows:
[0003] 1) Methanol from the tank farm is vaporized in a methanol vaporizer and mixed with hydrogen chloride gas from the methane chloride unit and hydrochloric acid decomposition in a certain proportion. The mixture is then fed to the chlorination reactor, where it undergoes a chlorination reaction at 160°C and 0.15 MPa(G) to synthesize monochloromethane. The reaction gas at the chlorination reactor outlet is cooled and partially condensed in a reflux condenser. The reflux condenser uses circulating water as a refrigerant, allowing excess hydrochloric acid and water to circulate back into the chlorination reactor.
[0004] 2) The downstream reaction gas is cooled to 55°C in a condenser cooler and sent as a two-phase flow to the 1# water scrubber, 2# water scrubber, and alkali scrubber. After two-stage water washing and one-stage alkali washing to remove hydrogen chloride and methanol from the chloromethane product, it is sent to the drying tower. After water washing, the alcohol-containing hydrochloric acid is sent to the hydrochloric acid storage tank in the intermediate tank area for temporary storage and then to the hydrochloric acid analysis device. The wastewater after alkali washing enters the wastewater tank for temporary storage and then is sent to the stripping unit.
[0005] The crude chloromethane is dried with three levels of sulfuric acid in the 1# drying tower, 2# drying tower and 3# drying tower. The water content and dimethyl ether produced as a by-product of the reaction are removed from the chloromethane by 98% concentrated sulfuric acid. The chloromethane gas after impurity removal is sent to the air inlet buffer tank.
[0006] 3) The chloroform product after deacidification and dehydration is pressurized to 0.95 MPaG by a chloroform compressor and then enters a chloroform distillation tower for refining; the chloroform product at the top of the tower is condensed by a top condenser and sent to a chloroform intermediate tank for temporary storage. After passing the inspection, it is sent to the finished product tank area.
[0007] The reaction formula is as follows:
[0008] HCl+CH3OH→CH3Cl+H2O.
[0009] However, in the chlorination reactor, because the vaporized methanol gas has a high temperature, it mixes with the low-temperature hydrogen chloride gas before entering the chlorination reactor, which will cause the methanol gas to condense in the pipeline, resulting in waste of raw materials and reduced reaction yield. Therefore, it is necessary to solve the problem of methanol gas liquefaction. Utility Model Content
[0010] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a feeding system for a chlorination reactor for preparing monochloromethane by a liquid phase process. Before the hydrogen chloride gas enters the chlorination reactor, the low-temperature hydrogen chloride gas is first heated by a hydrogen chloride heater using low-pressure steam, and a temperature control is set to increase and maintain the temperature at 95° C. before being mixed with methanol gas, thereby preventing gaseous methanol from liquefying when encountering the cold hydrogen chloride gas, reducing raw material waste, and improving the reaction yield.
[0011] The technical solution of the utility model is:
[0012] A feeding system for a chlorination reactor for preparing methyl chloride by a liquid phase process comprises a hydrogen chloride heater, the hydrogen chloride heater being connected to a steam feeding pipeline, a condensed water discharging pipeline, a hydrogen chloride feeding pipeline and a hydrogen chloride discharging pipeline, the hydrogen chloride discharging pipeline being connected to a hydrogen chloride feeding port of the chlorination reactor, and the chlorination reactor being further connected to a methanol feeding pipeline and a methyl chloride discharging pipeline; a steam feeding valve being provided on the steam feeding pipeline, a temperature sensor being provided on the hydrogen chloride discharging pipeline, and the steam feeding valve and the temperature sensor being electrically connected to a control system respectively.
[0013] Preferably, a methanol feed valve is provided on the methanol feed pipeline, and the methanol feed valve is electrically connected to the control system.
[0014] Preferably, a methanol flow meter is provided on the methanol feed pipeline, and the methanol flow meter is electrically connected to the control system.
[0015] Preferably, a hydrogen chloride discharge valve is provided on the hydrogen chloride discharge pipeline, and the hydrogen chloride discharge valve is electrically connected to the control system.
[0016] Preferably, a hydrogen chloride flow meter is provided on the hydrogen chloride discharge pipeline, and the hydrogen chloride flow meter is electrically connected to the control system.
[0017] Preferably, the methanol feed line, the hydrogen chloride discharge line and the methyl chloride discharge line are respectively connected to the top of the chlorination reactor.
[0018] Compared with the prior art, the present invention has the following beneficial effects:
[0019] The utility model first heats the low-temperature hydrogen chloride gas with low-pressure steam through a hydrogen chloride heater before the hydrogen chloride gas enters the chlorination reactor, and sets a temperature control to increase and maintain the temperature at 95° C. before mixing with the methanol gas, thereby preventing the gaseous methanol from liquefying after encountering the cold hydrogen chloride gas, reducing raw material waste, and improving the reaction yield. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1The utility model is a structural schematic diagram of a feeding system of a chlorination reactor for preparing monochloromethane by a liquid phase method.
[0021] In the figure, 1. Hydrogen chloride heater; 2. Steam feed pipeline; 201. Steam feed valve; 3. Condensate discharge pipeline; 4. Hydrogen chloride feed pipeline; 5. Hydrogen chloride discharge pipeline; 501. Hydrogen chloride discharge valve; 502. Hydrogen chloride flowmeter; 6. Chlorination reactor; 7. Methanol feed pipeline; 701. Methanol feed valve; 702. Methanol flowmeter; 8. Methyl chloride discharge pipeline; 9. Temperature sensor. DETAILED DESCRIPTION
[0022] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.
[0023] Example 1
[0024] like Figure 1 As shown, this embodiment provides a chlorination reactor feed system for preparing methyl chloride by a liquid phase process, comprising a hydrogen chloride heater 1, connected to a steam feed line 2, a condensed water discharge line 3, a hydrogen chloride feed line 4, and a hydrogen chloride discharge line 5. The hydrogen chloride discharge line 5 is connected to a hydrogen chloride feed port at the top of a chlorination reactor 6. The top of the chlorination reactor 6 is also connected to a methanol feed line 7 and a methyl chloride discharge line 8. The hydrogen chloride is heated by low-pressure steam and then enters the chlorination reactor 6 together with gaseous methanol to react.
[0025] like Figure 1 As shown, a steam feed valve 201 is provided on the steam feed line 2, and a temperature sensor 9 is provided on the hydrogen chloride discharge line 5. The steam feed valve 201 and the temperature sensor 9 are each electrically connected to a control system. The control system can preset a temperature of 95°C for the heated hydrogen chloride. When the temperature sensor 9 detects that the temperature of the heated hydrogen chloride in the hydrogen chloride discharge line 5 is above or below this temperature, the amount of steam introduced can be adjusted by regulating the opening of the steam feed valve 201 on the steam feed line 2, thereby maintaining the temperature of the heated hydrogen chloride at the preset 95°C. The hydrogen chloride heated to 95°C is then mixed with methanol gas before entering the chlorination reactor 6, preventing condensation of the gaseous methanol upon encountering the cold hydrogen chloride gas and improving the reaction yield.
[0026] At the same time, if Figure 1As shown, methanol feed line 7 is provided with a methanol feed valve 701 and a methanol flowmeter 702, and hydrogen chloride discharge line 5 is provided with a hydrogen chloride discharge valve 501 and a hydrogen chloride flowmeter 502. Methanol feed valve 701, methanol flowmeter 702, hydrogen chloride discharge valve 501, and hydrogen chloride flowmeter 502 are each electrically connected to a control system. Automatic control of the methanol and hydrogen chloride feed rates in chlorination reactor 6 is achieved through the methanol feed valve 701, methanol flowmeter 702, hydrogen chloride discharge valve 501, and hydrogen chloride flowmeter 502.
Claims
1. A chlorination reactor feeding system for preparing methyl chloride by a liquid phase process, characterized in that: The invention comprises a hydrogen chloride heater (1), wherein the hydrogen chloride heater (1) is connected to a steam feed pipeline (2), a condensed water discharge pipeline (3), a hydrogen chloride feed pipeline (4) and a hydrogen chloride discharge pipeline (5), wherein the hydrogen chloride discharge pipeline (5) is connected to a hydrogen chloride feed port of a chlorination reactor (6), and the chlorination reactor (6) is further connected to a methanol feed pipeline (7) and a methyl chloride discharge pipeline (8); a steam feed valve (201) is provided on the steam feed pipeline (2), and a temperature sensor (9) is provided on the hydrogen chloride discharge pipeline (5); and the steam feed valve (201) and the temperature sensor (9) are respectively electrically connected to a control system.
2. The chlorination reactor feeding system for preparing methyl chloride by the liquid phase method according to claim 1, characterized in that: The methanol feed pipeline (7) is provided with a methanol feed valve (701), and the methanol feed valve (701) is electrically connected to the control system.
3. The chlorination reactor feeding system for preparing monochloromethane by the liquid phase method according to claim 2, characterized in that: The methanol feed pipeline (7) is provided with a methanol flow meter (702), and the methanol flow meter (702) is electrically connected to the control system.
4. The chlorination reactor feeding system for preparing monochloromethane by the liquid phase method according to claim 1, characterized in that: The hydrogen chloride discharge pipeline (5) is provided with a hydrogen chloride discharge valve (501), and the hydrogen chloride discharge valve (501) is electrically connected to a control system.
5. The chlorination reactor feeding system for preparing monochloromethane by the liquid phase method according to claim 4, characterized in that: The hydrogen chloride discharge pipeline (5) is provided with a hydrogen chloride flow meter (502), and the hydrogen chloride flow meter (502) is electrically connected to the control system.
6. The chlorination reactor feeding system for preparing monochloromethane by the liquid phase method according to claim 1, characterized in that: The methanol feed pipeline (7), the hydrogen chloride discharge pipeline (5) and the methyl chloride discharge pipeline (8) are respectively connected to the top of the chlorination reactor (6).