Reduction furnace sequence control method based on DCS (distributed control System) of polycrystalline silicon production device
Technical Field
The invention relates to the technical field of automatic control, in particular to a reduction furnace sequence control method based on a DCS (distributed control System) of a polycrystalline silicon production device.
Background
The reduction furnace is driven in the polycrystalline silicon industry, the normal operation, the process operations such as parking need high quality operating personnel manual operation, carry out initial clean-up when driving, gas replacement, the pressure leakage inspection, observe vacuum tube line pressure, adjust the flow of each part, normal operation TCS, require to accomplish material balance and energy balance during H2 feeding, slow parking in all aspects is taken into account in the parking process and is prevented to cause the harm to equipment, complex operation, the work load is big, especially, many reduction furnaces are driven simultaneously, normal operation and parking, cause the maloperation easily, and because operating personnel control horizontal difference, the difference of reduction furnace operation is bigger, be unfavorable for the steady operation of apparatus for producing and the steady promotion of product quality.
Disclosure of Invention
The invention aims to solve the defects in the prior art, and provides a reduction furnace sequence control method based on a DCS (distributed control System) of a polycrystalline silicon production device, which realizes full-automatic control of the reduction furnace and improves the automatic operation level of enterprises.
In order to achieve the purpose, the invention adopts the following technical scheme:
a reduction furnace sequence control method based on a DCS system of a polycrystalline silicon production device comprises the following specific program operation steps:
s1, initial purge sequence control program: automatically opening a relevant valve by a program, vacuumizing to a specified pressure, keeping the specified pressure unchanged or not decreasing within a specified time, and automatically running the next step by the program or operating by an operator;
s2, pressure check sequence control program: the program automatically opens the relevant valve to charge to the specified pressure, the specified pressure is stable and the error is within the allowable range in the specified time, and the program automatically runs the next step or is operated by an operator;
s3, gas replacement sequence control program: the program automatically opens the relevant valves to pressurize to a specified pressure, then releases the pressure to the specified pressure, starts to execute the vacuumizing program to the specified pressure, and automatically runs the next step or is operated by an operator within specified times after repeating the steps;
s4, main reaction preparation sequence control program: the program automatically opens the relevant valves to release the pressure to the specified pressure and then pressurizes the pressure to the specified pressure, and after the steps are repeated within the specified times, the program pressurizes the pressure to the specified pressure and automatically runs the next step or is operated by an operator;
s5, a material feeding climbing program and a step switching program in the main reaction stage: the program automatically opens related valves, materials start to continuously and stably rise and feed at a specified feeding amount per hour according to a set prescription until the running time is finished, and the program automatically runs the next step or is operated by an operator;
s6, main reaction stop sequence control program: program closing the relevant valve;
s7, nitrogen replacement sequence control program: the program automatically opens the relevant valve to pressurize to the specified pressure and then releases the pressure to the specified pressure, and after the steps are repeated within the specified times, the program pressurizes to the specified pressure and automatically runs the next step or is operated by an operator;
s8, vacuum sequence control program: the program automatically opens the relevant valve to vacuumize to the specified pressure, the specified pressure is not changed or reduced within the specified time, the pressure is automatically released to the specified pressure within the specified times after the steps are repeated, and the program automatically runs the next step or is operated by an operator.
Preferably, when the whole program is running, an operator can execute the running or jumping of the program according to the actual situation, the whole program can run automatically, and the operator can decide the automatic running or manual running of the program according to the actual situation.
Compared with the prior art, the invention has the beneficial effects that:
the automatic control program realizes high-degree automatic sequence control program, does not need frequent manual operation, obviously reduces the operation frequency and labor intensity of staff, realizes safe interlocking of process parameters of the reduction furnace, automatically enters an emergency treatment operation program when abnormal conditions occur, reduces the safety risk of abnormal conditions of the reduction furnace caused by improper manual monitoring or misoperation, ensures safe and stable operation of the reduction furnace, simultaneously realizes continuous and stable feeding in the production process of polycrystalline silicon by the automatic control program, reduces human factor interference, and further obviously improves the stability of product quality.
Drawings
FIG. 1 is a sequence control operation picture program diagram of a reduction furnace of the reduction furnace sequence control method based on a DCS system of a polysilicon production device according to the present invention;
FIG. 2 is a configuration diagram of a sequence control starting program of the method for controlling the sequence of the reduction furnace based on the DCS system of the polysilicon production device according to the present invention;
FIG. 3 is a gate valve state diagram of a switching valve of the reduction furnace sequence control method based on the DCS system of the polysilicon production device according to the present invention;
FIG. 4 is a state diagram of a valve for determining the reduction furnace sequence control method based on the DCS system of the polysilicon production device;
FIG. 5 is a valve state diagram of the regulator valve in each of the procedures of the present invention;
FIGS. 6, 7 and 8 are second pressure checking sequence control program diagrams of the reduction furnace sequence control method based on the DCS system of the polysilicon production apparatus according to the present invention;
FIG. 9 is a program diagram of replacement times of the method for controlling the sequence of the reduction furnace based on the DCS system of the polysilicon production apparatus according to the present invention;
fig. 10 is a configuration diagram of an end program of the sequential control method for the reduction furnace based on the DCS system of the polysilicon production apparatus according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
Referring to fig. 1-10, a reduction furnace sequence control method based on a DCS system of a polysilicon production apparatus includes the following specific program operation steps:
s1, initial purge sequence control program: automatically opening a relevant valve by a program, vacuumizing to a specified pressure, keeping the specified pressure unchanged or not decreasing within a specified time, and automatically running the next step by the program or operating by an operator;
s2, pressure check sequence control program: the program automatically opens the relevant valve to charge to the specified pressure, the specified pressure is stable and the error is within the allowable range in the specified time, and the program automatically runs the next step or is operated by an operator;
s3, gas replacement sequence control program: the program automatically opens the relevant valves to pressurize to a specified pressure, then releases the pressure to the specified pressure, starts to execute the vacuumizing program to the specified pressure, and automatically runs the next step or is operated by an operator within specified times after repeating the steps;
s4, main reaction preparation sequence control program: the program automatically opens the relevant valves to release the pressure to the specified pressure and then pressurizes the pressure to the specified pressure, and after the steps are repeated within the specified times, the program pressurizes the pressure to the specified pressure and automatically runs the next step or is operated by an operator;
s5, a material feeding climbing program and a step switching program in the main reaction stage: the program automatically opens related valves, materials start to continuously and stably rise and feed at a specified feeding amount per hour according to a set prescription until the running time is finished, and the program automatically runs the next step or is operated by an operator;
s6, main reaction stop sequence control program: program closing the relevant valve;
s7, nitrogen replacement sequence control program: the program automatically opens the relevant valve to pressurize to the specified pressure and then releases the pressure to the specified pressure, and after the steps are repeated within the specified times, the program pressurizes to the specified pressure and automatically runs the next step or is operated by an operator;
s8, vacuum sequence control program: the program automatically opens the relevant valve to vacuumize to the specified pressure, the specified pressure is not changed or reduced within the specified time, the pressure is automatically released to the specified pressure within the specified times after the steps are repeated, and the program automatically runs the next step or is operated by an operator.
The picture in fig. 1 can realize automatic start and stop of the reduction furnace, each program can be manually controlled or automatically controlled in the whole process, each operation program has the functions of start, end and pause, the necessary replacement times function and the time setting function in the operation picture are automatically controlled, an operator needs to note or remember by himself in the replacement times, the replacement times function can enable the operator to automatically repeat replacement without taking a lot of trouble and only after the operator sets the replacement times, and the program automatically goes to the next step after the set replacement times are reached; the gate valve state of the on-off valve in each routine in fig. 3, without the need for an operator to manually control the on-off valve; this routine in fig. 4 determines whether the on-off valve state has reached the set point; in fig. 5, the valve state of the regulating valve is adjusted in each procedure, and the regulating valve is not required to be manually controlled by an operator, so that the temperature, the flow, the liquid level and the pressure are more accurately and rapidly adjusted; the second pressure checking sequence control program in fig. 6, 7 and 8 can realize automatic stamping, pressure maintaining, checking whether the pressure is qualified or not, and automatically re-maintaining the pressure if the pressure is unqualified; in the replacement number routine of fig. 9, the operator sets the number of times that needs to be replaced, and the routine automatically determines whether the number of times of replacement has reached the set number of times, and accordingly determines whether the routine performs the next step.
According to the invention, a high-degree automatic sequence control program is realized, frequent manual operation is not needed, the operation frequency and labor intensity of staff are obviously reduced, the safety interlocking of the process parameters of the reduction furnace is realized, when an abnormal condition occurs, the program automatically enters an emergency treatment operation program, the safety risk of the abnormal condition of the reduction furnace caused by insufficient manual monitoring or misoperation is reduced, the safe and stable operation of the reduction furnace is ensured, meanwhile, the automatic control program realizes continuous and stable feeding in the production process of polycrystalline silicon, the interference of human factors is reduced, and the stability of the product quality is obviously improved.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.