A device for chlorination reaction in maltol production and its use method

Abstract

A device for chlorination reaction in maltol production includes a liquid chlorine cylinder, a chlorine buffer tank, a chlorination kettle, and a furfuryl alcohol tank. A straight-through control valve is provided at the mouth of the liquid chlorine cylinder, and a chlorine supply pipe is connected to the control valve. The chlorine supply pipe is connected to the chlorine buffer tank. A pressure-stabilizing valve, a pneumatic regulating valve, and a mass flow meter are connected in series to the chlorine supply pipe. A first coil is provided between the mass flow meter and the chlorine buffer tank. A second coil is provided on the outside of the chlorine buffer tank body. The chlorine buffer tank is connected to the chlorination kettle, and the furfuryl alcohol is connected to the dripping port on the upper side of the chlorination kettle through the second coil. Usage method: open the control valve to control the liquid chlorine pressure, and control the flow rate through the mass flow meter and the pneumatic regulating valve; the first coil heats and vaporizes the liquid chlorine, and the furfuryl alcohol is pre-cooled by the second coil, and a chlorination reaction is carried out in the chlorination kettle. The liquid chlorine output pressure of the present invention is stable, and the liquid chlorine metering is more accurate, which is conducive to improving the product yield. Pre-cooling is performed before the furfuryl alcohol is added, saving energy.

Description

Technical Field

[0001] The invention relates to a device for chlorination reaction in maltol production and a use method thereof. Background Art

[0002] The maltol production process consists of the Grignard process, chlorination process, sublimation process, crystallization process, and drying process. The chlorination and sublimation processes include chlorination, chlorination hydrolysis, neutralization, and sublimation. In the chlorination process, liquid chlorine is vaporized in a water bath heater, then passed through a chlorine buffer tank, and finally piped to the production line and into a chlorination kettle for the chlorination reaction.

[0003] In the existing chlorination process, the pressure of the liquid chlorine cylinder fluctuates during use, causing the pressure of the liquid chlorine to become unstable after being vaporized by the water bath heater. This requires manual and frequent adjustment of the bottle mouth opening to regulate the pressure. This inevitably leads to unstable chlorine flow or untimely adjustment, resulting in a disproportionate amount of chlorine flow and the amount of furfuryl alcohol added, deviating from process indicators, affecting the chlorination reaction and causing production fluctuations. Summary of the Invention

[0004] The first technical problem to be solved by the present invention is to provide a device for chlorination reaction in maltol production, wherein the liquid chlorine output pressure is stable and the liquid chlorine metering is more accurate, which is beneficial to improving the product yield. Pre-cooling is performed before the furfuryl alcohol is added dropwise, thereby saving energy consumption.

[0005] The second technical problem to be solved by the present invention is to provide a method for using the above-mentioned device for chlorination reaction in maltol production. The method has simple steps, is easy to operate, does not require manual intervention throughout the process, and has strong stability.

[0006] To solve the first technical problem mentioned above, the present invention provides a device for a chlorination reaction in maltol production, comprising a liquid chlorine cylinder, a chlorine buffer tank, a chlorination kettle, and a furfuryl alcohol tank. The liquid chlorine cylinder is arranged horizontally, and a control valve is provided at the mouth of the liquid chlorine cylinder. The control valve is a straight-through valve, and the axis of the control valve pipeline is parallel to the axis of the liquid chlorine cylinder. A chlorine delivery pipe is connected to the control valve, and the other end of the chlorine delivery pipe is connected to the inlet of the chlorine buffer tank. The side of the chlorine delivery pipe close to the liquid chlorine cylinder is defined as the front, and the side away from the liquid chlorine cylinder is defined as the rear. A pressure-stabilizing valve, a pneumatic regulating valve and a mass flowmeter are sequentially connected in series on the chlorine delivery pipe from front to back. A first coil is provided at a position on the chlorine delivery pipe corresponding to the mass flowmeter and the chlorine buffer tank. The chlorine buffer tank includes a buffer tank body. A second coil matching the buffer tank body is provided on the circumferential outer side of the buffer tank body. The chlorine buffer tank outlet is connected to the lower side of the chlorination kettle through a pipeline. The furfural alcohol tank output pipeline is connected to one end of the second coil. The other end of the second coil away from the furfural alcohol tank is connected to the dripping port on the upper side of the chlorination kettle.

[0007] To solve the above second technical problem, the present invention provides a method for using a device for chlorination reaction in maltol production, comprising the following steps:

[0008] (1) Open the control valve at the mouth of the liquid chlorine cylinder to the target opening so that the pressure in the chlorine delivery pipe is controlled at 0.02~0.04MPa;

[0009] (2) Liquid chlorine passes through the pressure regulating valve, pneumatic control valve and mass flow meter in sequence. Based on the reading feedback of the mass flow meter, the pneumatic control valve is used to control the liquid chlorine flow rate at 130 kg / h;

[0010] (3) Circulating water is introduced into the first coil to heat the liquid chlorine. The liquid chlorine is heated and vaporized by the coil and then enters the buffer tank. Then, it enters the chlorination kettle from the bottom side. The circulating water temperature in the first coil is 80-90℃.

[0011] (4) The furfuryl alcohol in the furfuryl alcohol tank is pre-cooled through the second coil at a flow rate of 220 L / h. The pre-cooled furfuryl alcohol is dripped into the chlorination kettle from the dripping port on the upper side of the chlorination kettle for chlorination reaction, and the chlorination reaction temperature is controlled to be less than -7 °C.

[0012] Advantages of the present invention:

[0013] 1. The liquid chlorine output pressure of the device of the present invention is stable, and there is no need to frequently adjust the control valve at the mouth of the liquid chlorine cylinder to stabilize the pressure, which is convenient for operation.

[0014] 2. Pre-cooling is performed before adding furfuryl alcohol to save energy.

[0015] 3. The precise control of liquid chlorine metering by pneumatic regulating valve and mass flow meter is more accurate, ensuring that the amount of chlorine passed and the amount of furfuryl alcohol added are proportional and stable, which is beneficial to improving product yield.

[0016] 4. The usage steps are simple, the operation is convenient, no manual intervention is required throughout the process, and the stability is strong. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0018] See also Figure 1A device for chlorination reaction in maltol production, comprising a liquid chlorine cylinder 1, a chlorine buffer tank 2, a chlorination kettle 3 and a furfuryl alcohol tank 4, wherein the liquid chlorine cylinder 1 is arranged horizontally, and a control valve 11 is provided at the bottle mouth of the liquid chlorine cylinder 1, the control valve 11 is a straight-through valve, and the axis of the control valve 11 pipeline is parallel to the axis of the liquid chlorine cylinder 1, the control valve 11 is connected to a chlorine delivery pipe, the other end of the chlorine delivery pipe is connected to the inlet of the chlorine buffer tank 2, the side of the chlorine delivery pipe close to the liquid chlorine cylinder 1 is set as the front, and the side away from the liquid chlorine cylinder 1 is set as the rear, and the chlorine delivery pipe is arranged from front to rear in order. A pressure-stabilizing valve 4, a pneumatic regulating valve 5 and a mass flowmeter 6 are connected in series. A first coil 7 is provided between the mass flowmeter 6 and the chlorine buffer tank 2 at the position of the chlorine delivery pipe. The chlorine buffer tank 2 includes a buffer tank 2 body. A second coil 21 matching the buffer tank 2 body is provided on the circumferential outer side of the buffer tank 2 body. The outlet of the chlorine buffer tank 2 is connected to the lower side of the chlorination kettle 3 through a pipeline. The output pipeline of the furfural alcohol tank 4 is connected to one end of the second coil 21. The other end of the second coil 21 away from the furfural alcohol tank 4 is connected to the dripping port on the upper side of the chlorination kettle 3.

[0019] To solve the above second technical problem, the present invention provides a method for using a device for chlorination reaction in maltol production, comprising the following steps:

[0020] (1) Open the control valve 11 at the mouth of the liquid chlorine cylinder 1 to the target opening so that the pressure in the chlorine delivery pipe is controlled at 0.02~0.04MPa;

[0021] (2) Liquid chlorine passes through the pressure regulating valve 4, the pneumatic regulating valve 5 and the mass flow meter 6 in sequence. Based on the reading feedback of the mass flow meter 6, the liquid chlorine flow rate is controlled at 130 kg / h through the pneumatic regulating valve 5;

[0022] (3) Circulating water is introduced into the first coil 7 to heat the liquid chlorine. The liquid chlorine is heated and vaporized by the coil and then enters the buffer tank 2. Then, it enters the chlorination kettle 3 from the bottom side. The temperature of the circulating water in the first coil 7 is 80-90°C.

[0023] (4) The furfuryl alcohol in the furfuryl alcohol tank 4 is pre-cooled at a flow rate of 220 L / h through the second coil 21. The pre-cooled furfuryl alcohol is dripped into the chlorination kettle 3 from the dripping port on the upper side of the chlorination kettle 3 to carry out chlorination reaction. The chlorination reaction temperature is controlled to be less than -7°C.

Claims

1. A method for using a chlorination reaction device in maltol production, characterized in that: The chlorination reaction device includes a liquid chlorine cylinder, a chlorine buffer tank, a chlorination kettle and a furfuryl alcohol tank. The liquid chlorine cylinder is arranged horizontally. A control valve is provided at the bottle mouth of the liquid chlorine cylinder. The control valve is a through valve, and the axis of the control valve pipeline is parallel to the axis of the liquid chlorine cylinder. A chlorine delivery pipe is connected to the control valve, and the other end of the chlorine delivery pipe is connected to the inlet of the chlorine buffer tank. The side of the chlorine delivery pipe close to the liquid chlorine cylinder is defined as the front, and the side away from the liquid chlorine cylinder is defined as the rear. A pressure-stabilizing valve, a pneumatic regulating valve and a mass flow meter are sequentially connected in series on the chlorine delivery pipe from front to back. A first coil is provided at the position of the chlorine delivery pipe corresponding to the mass flow meter and the chlorine buffer tank. The chlorine buffer tank includes a buffer tank body, a second coil matching the buffer tank body is provided on the circumferential outer side of the buffer tank body, the chlorine buffer tank outlet is connected to the lower side of the chlorination kettle through a pipeline, the furfuryl alcohol tank output pipeline is connected to one end of the second coil, and the other end of the second coil away from the furfuryl alcohol tank is connected to the dripping port on the upper side of the chlorination kettle; The method of use includes the following steps: (1) Open the control valve at the mouth of the liquid chlorine cylinder to the target opening, so that the pressure in the chlorine delivery pipe is controlled at 0.02~0.04MPa; (2) The liquid chlorine passes through the pressure regulating valve, pneumatic control valve and mass flow meter in sequence. Based on the reading feedback of the mass flow meter, the liquid chlorine flow rate is controlled at 130kg / h through the pneumatic control valve; (3) Circulating water is introduced into the first coil to heat the liquid chlorine. The liquid chlorine is heated and vaporized by the coil and then enters the buffer tank. Then, it enters the chlorination kettle from the bottom side. The circulating water temperature in the first coil is 80-90℃. (4) The furfuryl alcohol in the furfuryl alcohol tank is pre-cooled through the second coil at a flow rate of 220 L / h. The pre-cooled furfuryl alcohol is dripped into the chlorination kettle from the dripping port on the upper side of the chlorination kettle for chlorination reaction, and the chlorination reaction temperature is controlled to be less than -7 °C.

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