Method for controlling evaporation tank with single valve sequentially opened and closed and capable of stably and automatically rotating and stopping

Abstract

The invention discloses a control method for a single-valve sequential switching stable automatic rotating and stopping evaporating tank, which reduces labor intensity and safety accidents, is beneficial to quick recovery of stable operation of the evaporating tank, ensures that the brix degree of evaporated syrup reaches 65Bx degrees and ensures smooth production, and is used in a five-effect evaporating device. The method comprises the following steps: S1, starting a fourth evaporation tank D, stopping a fifth evaporation tank E, starting the fifth evaporation tank E after evaporation operation is performed in the fourth evaporation tank D, stopping a sixth standby evaporation tank F, starting the sixth standby evaporation tank F after evaporation operation is performed in the fifth evaporation tank E, stopping a third evaporation tank C after evaporation operation is performed in the fifth evaporation tank E, and stopping the fifth evaporation tank E after evaporation operation is performed in the third evaporation tank C; performing evaporation operation in a sixth standby evaporation tank F; and S2, starting a third evaporation tank C, and after stopping the second evaporation tank B, carrying out evaporation operation in the third evaporation tank C. The evaporation tank is sequentially opened and closed through a single valve to stably and automatically rotate and stop, stability of steam and materials can be kept in the process, stability of juice steam for sugar boiling, heating and pumping is kept, and stability of syrup brix is kept.

Description

Technical Field

[0001] This application relates to the technical field of sugar production, in particular to a control method for a single-valve sequential switching smooth automatic transfer and stop evaporation pan, which can realize that the fluctuation range of the syrup Brix degree ≤ 5Bx° during continuous production, effectively ensure the stability of the syrup Brix degree during the transfer and stop process, and is beneficial to the quality uniformity of the sucrose obtained in the downstream processing process; effectively avoid equipment failures or low squeezing amounts, small sugar juice flow rates, increased steam flow rates, increased temperatures, and evaporation incentives that cause the evaporation pan to dry out, and improve the safety and reliability of the continuous production process. Background Art

[0002] The evaporation pan in a sugar factory is the thermal center of the sugar factory and is in the central link of the sugar production process, which is of great significance to the steam and material balance of the whole factory. Currently, cane sugar factories mainly adopt five-effect evaporation, with 6 evaporation pans configured, 5 for use and 1 as a spare. During the use of the evaporation pans, one pan needs to be washed in rotation every day, and the operation of transferring and stopping the evaporation pans needs to be carried out once a day. During the process of transferring and stopping the evaporation pans, due to the large number of valves involved and the large spatial distances of many valves in the front, back, up, and down directions, a large number of workers are required for manual pan transfer. When there is a shortage of workers in this position during the transfer and stop of the pans, workers from other positions need to be borrowed. However, these workers lack operation experience, and the proportion of operation errors is relatively high, which is likely to cause production safety accidents. It is also easy to frequently occur situations of improper or incorrect operation of opening and closing valves during the transfer and stop process.

[0003] Due to operation errors, during the process of transferring and stopping the pans, the steam fluctuates violently and the transported materials are unbalanced, resulting in unstable steam flow in the sugar boiling and heating and juice extraction links, and further causing serious fluctuations in the Brix degree of the syrup obtained from continuous production; when the steam fluctuation is too severe, it even causes the front-effect pan to dry out and the back-pressure steam to overpressure and trip the safety valve. These situations have a serious adverse impact on normal sugar production.

[0004] The information disclosed in the background art section is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as an admission or any form of suggestion that this information constitutes the prior art already known to those of ordinary skill in the art. Summary of the Invention

[0005] This application provides a control method for a single-valve sequential switching smooth automatic transfer and stop evaporation pan for the above technical problems. This method can realize that the fluctuation range of the syrup Brix degree ≤ 5Bx° during continuous production, effectively ensure the stability of the syrup Brix degree during the transfer and stop process, and is beneficial to the quality uniformity of the sucrose obtained in the downstream processing process; effectively avoid equipment failures or low squeezing amounts, small sugar juice flow rates, increased steam flow rates, increased temperatures, and evaporation incentives that cause the evaporation pan to dry out, and improve the safety and reliability of the continuous production process.

[0006] The present application provides a control method for a single-valve sequential-switching smooth automatic transfer and stop evaporation tank, which is used in a five-effect evaporation device. The five-effect evaporation device includes: a first evaporation tank A, a second evaporation tank B, a third evaporation tank C, a fourth evaporation tank D, a fifth evaporation tank E, a sixth standby evaporation tank F, a mixed saturated steam pipe (13), a clear juice conveying pipe (12), a steam condensate conveying pipe (11), a low-temperature steam conveying pipe (14), a first-effect juice steam conveying pipe (15), a second-effect juice steam conveying pipe (16), a heater heating juice steam conveying pipe (17), and a plurality of supporting valves;

[0007] The first evaporation tank A, the second evaporation tank B, the third evaporation tank C, the fourth evaporation tank D, the fifth evaporation tank E, and the sixth standby evaporation tank F are respectively connected to the mixed saturated steam pipe (13), the clear juice conveying pipe (12), the steam condensate conveying pipe (11), the low-temperature steam conveying pipe (14), the first-effect juice steam conveying pipe (15), the second-effect juice steam conveying pipe (16), and the heater heating juice steam conveying pipe (17) through pipelines; supporting valves are arranged on the connecting pipelines;

[0008] After the tank transfer preparation is completed, the operations of starting and stopping each evaporation tank are carried out in the following order:

[0009] Step S1: Enable the fourth evaporation tank D, disable the fifth evaporation tank E, perform evaporation operation in the fourth evaporation tank D, then enable the fifth evaporation tank E, disable the sixth standby evaporation tank F, perform evaporation operation in the fifth evaporation tank E, then enable the sixth standby evaporation tank F, disable the third evaporation tank C, and perform evaporation operation in the sixth standby evaporation tank F;

[0010] Step S2: Enable the third evaporation tank C, disable the second evaporation tank B, perform evaporation operation in the third evaporation tank C, then enable the second evaporation tank B, disable the third evaporation tank C, perform evaporation operation in the second evaporation tank B, then enable the first evaporation tank A, disable the fourth evaporation tank D, perform evaporation operation in the first evaporation tank A, and then return to Step S1.

[0011] Preferably, "enable the fourth evaporation tank D, disable the fifth evaporation tank E" includes the following operations:

[0012] Step S111: After draining water and gas from the fourth evaporation tank D after cooking and disinfection, close all the valves connected to the fourth evaporation tank D, and close the juice outlet valve C12 of the third evaporation tank C 15 minutes before the tank transfer to increase the liquid level of the third evaporation tank C;

[0013] Step S112: Close the juice inlet valve E11 of the fifth evaporator E, close the juice outlet valve E12 of the fifth evaporator E, close the juice passing partition valve D13 of the fourth evaporator D, open the juice inlet valve D11 of the fourth evaporator D. When the liquid level in the fourth evaporator D reaches one-third of the drum height after juice inlet, open the juice inlet steam valve D3 of the fourth evaporator D, open the steam condensate discharge valve D15 of the fourth evaporator D, open the steam condensate post partition valve D17 of the fourth evaporator D, and open the juice steam three-way valve D1 of the fourth evaporator D;

[0014] Step S113: Close the juice steam three-way valve E1 of the fifth evaporator E, open the heating extraction 4-effect juice steam valve E9 of the fifth evaporator E, close the heating extraction 4-effect juice steam valve D9 of the fourth evaporator D, close the juice steam inlet valve E3 of the fifth evaporator E, close the steam condensate discharge valve E16 of the fifth evaporator E, and close the steam condensate pre partition valve E17 of the fifth evaporator E.

[0015] Preferably, "enable the fifth evaporator E and disable the sixth standby evaporator F" includes the following operations:

[0016] Step S121: After draining water and gas from the fifth evaporator E after cooking and disinfection, close all valves on the pipeline connected to the fifth evaporator E. 15 minutes before tank transfer, throttle down the juice outlet valve E12 of the fourth standby evaporator D to increase the liquid level in the fourth evaporator D;

[0017] Step S122: Close the juice inlet valve F11 of the sixth standby evaporator F, and at the same time temporarily stop pumping syrup. Close the juice outlet valve F12 of the sixth standby evaporator F, close the juice passing partition valve E13 of the fifth evaporator E, open the juice inlet valve E11 of the fifth evaporator E, open the juice passing partition valve F13 of the sixth standby evaporator F. When the liquid level in the fifth evaporator E reaches one-third of the drum height after juice inlet, open the juice inlet steam valve E3 of the fifth evaporator E;

[0018] Step S123: Open the steam condensate discharge valve E15 of the fifth evaporator E, open the steam condensate partition valve E17 of the fifth evaporator E, open the juice steam three-way valve E1 of the fifth evaporator E, open the heating extraction 4-effect valve D9, close the heating extraction 4-effect valve E9, close the juice steam three-way valve F1 of the sixth standby evaporator F, close the juice steam inlet valve F3 of the sixth standby evaporator F, and close the steam condensate discharge valve F16 of the sixth standby evaporator F.

[0019] Preferably, "enable the sixth standby evaporator F and disable the third evaporator C" includes the following operations:

[0020] Step S131: After draining water and gas from the sixth standby evaporator F after cooking and disinfection, close all valves on the pipeline connected to the sixth standby evaporator F. 15 minutes before tank transfer, throttle down the juice outlet valve B12 of the second evaporator B to increase the liquid level in the second evaporator B;

[0021] Step S132: Close the juice bypass valve F13 of the sixth standby evaporator F, open the juice inlet valve F11 of the sixth standby evaporator F. When the liquid level in the sixth standby evaporator F reaches one-third of the steam drum height after juice inlet, open the juice steam inlet valve F of the sixth standby evaporator F, open the steam condensate discharge valve F15 of the sixth standby evaporator F, close the steam condensate post-isolation valve E17 of the fifth evaporator E, open the steam condensate pre-isolation valve E16 of the fifth evaporator E, open the juice steam three-way valve F1 of the sixth standby evaporator F, open the heating extraction 4-effect steam valve E9, close the heating extraction 4-effect steam valve D9, and close the juice inlet valve C11 of the third evaporator C;

[0022] Step S133: Close the juice outlet valve C12 of the third evaporator C, open the juice bypass valve C13 of the third evaporator C, close the juice steam three-way valve C1 of the third evaporator C, open the fourth heating extraction 3-effect steam valve D8, close the third heating extraction 3-effect steam valve C8, close the third inlet steam valve C3 of the third evaporator C, open the steam condensate pre-isolation valve D15 of the fourth evaporator D, close the steam condensate post-isolation valve D17 of the fourth evaporator D, close the steam condensate valve C15 of the third evaporator C, and close the steam condensate post-isolation valve C17 of the third evaporator C.

[0023] Preferably, "enable the third evaporator C and disable the second evaporator B" includes the following operations:.

[0024] Step S211: After the third evaporator C is drained of water and gas after steaming and disinfection, close all valves on the pipeline connected to the third evaporator C. Reduce the juice outlet valve B12 of the second evaporator B 15 minutes before tank transfer to increase the liquid level of the second evaporator B; when the liquid level reaches more than one sight glass, open the juice inlet valve C11 so that the sugar juice in the third evaporator reaches two-thirds of the steam drum heating surface before the tank transfer and stop operation can be carried out.

[0025] Step S212: Close the juice bypass valve C13 of the third evaporator C, open the juice inlet valve C11 of the third evaporator C. When the liquid level in the third evaporator C reaches one-third of the steam drum height after juice inlet, open the juice steam inlet valve C3 of the third evaporator C, open the steam condensate discharge valve C15 of the third evaporator C, open the steam condensate pre-isolation valve C16 of the third evaporator C, open the juice steam three-way valve C1 of the third evaporator C, open the juice outlet valve C12 of the third evaporator C, close the juice steam three-way valve B1 of the second evaporator B, open the juice bypass valve B13 of the second evaporator B, and close the juice inlet valve B11 of the second evaporator B;

[0026] Step S213: Close the juice outlet valve C12 of the third evaporator C, open the juice bypass valve C13 of the third evaporator C, close the juice steam three-way valve C1 of the third evaporator C, open the heating extraction 3-effect steam valve D8 of the fourth evaporator D, close the heating extraction 3-effect steam valve C8 of the third evaporator C, close the juice steam inlet valve C3 of the third evaporator C, open the condensate front bypass valve D15 of the fourth evaporator D, close the condensate rear bypass valve D17 of the fourth evaporator D, close the condensate valve C15 of the third evaporator C, and close the condensate rear bypass valve C17 of the third evaporator C.

[0027] Preferably, "enable the second evaporator B and disable the first evaporator A" includes the following operations:

[0028] Step S221: After draining water and gas from the second evaporator B after cooking and disinfection, close all valves on the pipeline connected to the second evaporator B. Reduce the juice outlet valve A12 of the first evaporator A 15 minutes before tank transfer to increase the liquid level of the first evaporator A; when the liquid level reaches above one sight glass, open the juice inlet valve B11 so that the sugar juice in the second evaporator reaches two-thirds of the steam drum heating surface before the tank transfer and stop operation can be carried out.

[0029] Step S222: Open the juice inlet valve B11 of the second evaporator B, close the juice bypass valve B13 of the second evaporator B. When the sugar juice enters the second evaporator B and the liquid level is not less than one-third of the height of the heating tubes, open the mixed steam inlet valve B2 of the second evaporator B, open the condensate discharge valve B15 of the second evaporator B, open the condensate front bypass valve B16 of the second evaporator B, open the juice steam three-way valve B1 of the second evaporator B to 50%, open the juice bypass valve A13 of the first evaporator A, and close the juice inlet valve A11 of the first evaporator A;

[0030] Step S223: Close the juice outlet valve A12 of the first evaporator A, close the mixed steam inlet valve A2 of the first evaporator A, close the condensate discharge valve A15 of the first evaporator A, fully open the juice steam three-way valve B1 of the second evaporator B, open the sugar boiling extraction 1-effect steam valve B4 of the second evaporator B, close the sugar boiling extraction 1-effect steam valve A4 of the first evaporator A, open the heating extraction 1-effect steam valve B6 of the second evaporator B, and close the heating extraction 1-effect steam valve A6 of the first evaporator A.

[0031] Preferably, "enable the first evaporator A and disable the fourth evaporator D" includes the following operations:

[0032] Step S231: After draining water and gas from the first evaporator A after steam sterilization, close all valves on the pipeline connected to the first evaporator A. 15 minutes before tank transfer, throttle down the juice outlet valve C12 of the second evaporator B to increase the liquid level of the second evaporator B. When the liquid level reaches above one sight glass, open the juice inlet valve A11 to make the sugar juice in the first evaporator reach two-thirds of the steam drum heating surface before the tank transfer and stop operation can be carried out.

[0033] Step S232: Open the juice inlet valve A11 of the first evaporator A and close the juice passing partition valve A13 of the first evaporator A. When the sugar juice enters the first evaporator A and the liquid level in the heating tubes is not less than one-third of the height, open the mixed steam inlet valve A2 of the first evaporator A, open the juice steam inlet valve B3 of the second evaporator B, open the steam condensate discharge valve A15 of the first evaporator A, close the front partition valve B16 of the steam condensate of the second evaporator B, and open the rear partition valve B17 of the steam condensate of the second evaporator B. When the liquid level in the second evaporator B reaches the normal liquid level at a position 3 meters upward from the bottom of the tank, close the mixed steam inlet valve B2 of the second evaporator B, open the sugar boiling extraction 1st effect steam valve A4 of the first evaporator A, close the sugar boiling extraction 1st effect steam valve B4 of the second evaporator B, open the heating extraction 1st effect steam valve A6 of the first evaporator A, and close the heating extraction 1st effect steam valve B6 of the second evaporator B;

[0034] Step S233: Open the sugar boiling extraction 2nd effect steam valve B5 of the second evaporator B, close the sugar boiling extraction 2nd effect steam valve C5 of the third evaporator C, open the heating extraction 2nd effect steam valve B7 of the second evaporator B, close the heating extraction 2nd effect steam valve C7 of the third evaporator C, close the juice steam three-way valve D1 of the fourth evaporator D, close the juice inlet valve D11 of the fourth evaporator D, open the juice passing partition valve D13 of the fourth evaporator D, close the juice outlet valve D12 of the fourth evaporator D, close the steam condensate discharge valve D15 of the fourth evaporator D, close the front partition valve D16 of the steam condensate of the fourth evaporator D, close the front partition valve E16 of the steam condensate of the third evaporator C, and open the rear partition valve E17 of the steam condensate of the third evaporator C.

[0035] Preferably, a first mixed steam inlet valve A2 is provided on the pipeline where the first evaporation tank A is connected to the mixed saturated steam pipe 13; a first juice inlet valve A11 is provided on the pipeline where the juice inlet of the first evaporation tank A is connected to the clarified juice conveying pipe 12; a first steam condensate discharge valve A15 is provided on the pipeline where the first evaporation tank A is connected to the steam condensate conveying pipe 11; a first juice outlet valve A12 is provided on the pipeline where the juice outlet of the first evaporation tank A is connected to the clarified juice conveying pipe 12; a first sugar boiling extraction 1st effect juice steam valve A4 is provided on the pipeline where the first evaporation tank A is connected to the first effect juice steam conveying pipe 15; a first heating extraction 1st effect juice steam valve A6 is provided on the pipeline where the first evaporation tank A is connected to the heater heating juice steam conveying pipe 17; a first heating juice steam isolation valve A10 is provided on the heater heating juice steam conveying pipe 17; a first juice passing isolation valve A13 is provided between the connection points of the branches where the first juice inlet valve A11 and the first juice outlet valve A12 are connected to the clarified juice conveying pipe 12.

[0036] Preferably, a second mixed steam inlet valve B2 is provided on the pipeline where the second evaporation tank B is connected to the first evaporation tank A; a second juice outlet valve B12 is provided on the pipeline where the juice outlet of the second evaporation tank B is connected to the clarified juice conveying pipe 12; a second juice inlet valve B11 is provided on the pipeline where the juice inlet of the second evaporation tank B is connected to the clarified juice conveying pipe 12; a second steam condensate discharge valve B15 is provided on the pipeline where the second evaporation tank B is connected to the steam condensate conveying pipe 11; a second steam condensate front isolation valve B16 and a second steam condensate rear isolation valve B17 are provided on the steam condensate conveying pipe 11 on both sides of the connection point where the pipeline where the second steam condensate discharge valve B15 is provided is connected to the steam condensate conveying pipe 11; a second juice passing isolation valve B13 is provided between the connection points of the branches where the second juice inlet valve B11 and the second juice outlet valve B12 are connected to the clarified juice conveying pipe 12.

[0037] Preferably, a third juice steam inlet valve C3 is provided on the pipeline where the third evaporation tank C is connected to the low-temperature steam conveying pipe 14; a third juice outlet valve C12 is provided on the pipeline where the juice outlet of the third evaporation tank C is connected to the clarified juice conveying pipe 12; a third juice inlet valve C11 is provided on the pipeline where the juice inlet of the third evaporation tank C is connected to the clarified juice conveying pipe 12; a third steam condensate discharge valve C15 is provided on the pipeline where the third evaporation tank C is connected to the steam condensate conveying pipe 11; a third steam condensate front isolation valve C16 and a third steam condensate rear isolation valve C17 are provided on the steam condensate conveying pipe 11 on both sides of the connection point where the pipeline where the third steam condensate discharge valve C15 is provided is connected to the steam condensate conveying pipe 11; a third juice passing isolation valve C13 is provided between the connection points of the branches where the third juice inlet valve C11 and the third juice outlet valve C12 are connected to the clarified juice conveying pipe 12.

[0038] The beneficial effects that can be produced by this application include:

[0039] 1) The single-valve sequential-switching smooth automatic transfer and stop evaporation pan control method provided by this application uses a single-valve sequential-switching smooth automatic transfer and stop evaporation pan, which can maintain the smoothness of steam and materials during the process, maintain the stability of sugar boiling and heating for extracting juice steam, and maintain the stability of syrup Brix at ≥65 Bx°. This control method effectively saves labor and reduces labor intensity.

[0040] 2) The single-valve sequential-switching smooth automatic transfer and stop evaporation pan control method provided by this application can also avoid the situation of dry pans in the previous effect, and at the same time avoid the situation where the back-pressure steam adjusts the safety valve due to overpressure of the tank body, affecting the normal progress of production, and ensure the smooth progress of continuous production. Description of the Drawings

[0041] Figure 1 Schematic diagram of the pipeline connection structure of the five-effect evaporation device applicable to the single-valve sequential-switching smooth automatic transfer and stop evaporation pan control method provided by this application;

[0042] Legend:

[0043] First evaporation pan A, first mixed steam inlet valve A2, first juice inlet valve A11, first steam condensate discharge valve A15, first over-juice isolation valve A13, first juice outlet valve A12, first sugar-boiling extraction of 1st-effect juice steam valve A4, first heating extraction of 1st-effect juice steam valve A6, first heating juice steam isolation valve A10,

[0044] Second evaporation pan B, second mixed steam inlet valve B2, second juice inlet valve B11, second steam condensate discharge valve B15, second over-juice isolation valve B13, second juice outlet valve B12, second sugar-boiling extraction of 1st-effect juice steam valve B4, second heating extraction of 1st-effect juice steam valve B6, second heating juice steam isolation valve B10, second juice steam three-way valve B1, second juice steam inlet valve B3, second steam condensate front isolation valve B16, second steam condensate rear isolation valve B17, second sugar-boiling extraction of 2nd-effect juice steam valve B5, second heating extraction of 2nd-effect juice steam valve B7,

[0045] Third evaporation pan C, third juice inlet valve C11, third steam condensate discharge valve C15, third over-juice isolation valve C13, third juice outlet valve C12, third heating juice steam isolation valve C10, third juice steam three-way valve C1, third juice steam inlet valve C3, third steam condensate front isolation valve C16, third steam condensate rear isolation valve C17, third sugar-boiling extraction of 2nd-effect juice steam valve C5, third heating extraction of 2nd-effect juice steam valve C7, third heating extraction of 3rd-effect juice steam valve C8,

[0046] Fourth evaporator D, fourth juice inlet valve D11, fourth steam condensate discharge valve D15, fourth juice passing partition valve D13, fourth juice outlet valve D12, fourth heated juice steam partition valve D10, fourth juice steam three-way valve D1, fourth juice steam inlet valve D3, fourth steam condensate front partition valve D16, fourth steam condensate rear partition valve D17, fourth heating extraction of 3-effect juice steam valve D8, fourth heating extraction of 4-effect juice steam valve D9,

[0047] Fifth evaporator E, fifth juice inlet valve E11, fifth steam condensate discharge valve E15, fifth juice passing partition valve E13, fifth juice outlet valve E12, fifth heated juice steam discharge valve E6, fifth heated juice steam partition valve E10, fifth juice steam three-way valve E1, fifth juice steam inlet valve E3, fifth steam condensate front partition valve E16, fifth steam condensate rear partition valve E17, fifth heating extraction of 4-effect juice steam valve E9, fifth syrup tank balance valve E14,

[0048] Sixth juice inlet valve F11, sixth green juice discharge valve F12, sixth juice steam three-way valve F1, sixth juice steam inlet valve F3, sixth heated juice steam partition valve F10, sixth green juice interception valve F13, sixth syrup tank balance valve F14, sixth steam condensate discharge valve F15,

[0049] Mixed saturated steam pipe 13, clear juice conveying pipe 12, steam condensate conveying pipe 11, low-temperature steam conveying pipe 14, 1-effect juice steam conveying pipe 15, 2-effect juice steam conveying pipe 16, heater heated juice steam conveying pipe 17. Detailed implementation manners

[0050] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. The components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations.

[0051] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0052] The technical means not detailed in this application and not used to solve the technical problems of this application are set according to common general knowledge in the art, and various common general knowledge setting methods can be implemented.

[0053] See Figure 1, the single-valve sequential switch stable automatic transfer and stop evaporation tank control method provided by this application is applied to a five-effect evaporation device; the specific operation process is as follows:

[0054] I. Prepare operations before tank transfer

[0055] 1. Inspect the standby tank that has been washed and boiled with water, check and close various valves that need to be closed in advance, such as the drain bottom valve, water valve, steam valve, and material valve, and confirm that the bottom cover and manhole are well closed and tightened.

[0056] 2. Conduct the operation of boiling water for warming the pipes and warming the tank for the standby tank. Drain all the boiling water in the tank.

[0057] 3. 15 minutes before the tank transfer and stop, notify the relevant departments (sugar boiling post, boiler post, water treatment post, dispatching, electrician) to make preparations, and notify the shift leader to prepare for the tank transfer.

[0058] 4. Before the start of the tank transfer, the evaporation liquid levels of each effect should be adjusted. Appropriately raise the liquid level of the previous-effect evaporation tank of the tank to be started to facilitate the inlet of juice into the started evaporation tank. When there is a change in the I-effect tank sequence and a steam inlet conversion of the mixed steam occurs, measures should be taken to first appropriately reduce the back pressure steam pressure.

[0059] II. Arrangement of the rotation sequence of six tanks

[0060] To reduce production fluctuations, the tank transfer operation is carried out in the following order.

[0061] There are currently six tanks (one standby), and five-effect evaporation is adopted. The rotation and stop cycle sequence of each tank is: No. 4 (the fourth evaporation tank D) → No. 5 (the fifth evaporation tank E) → No. 6 (the sixth standby evaporation tank F) → No. 3 (the third evaporation tank C) → No. 2 (the second evaporation tank B) → No. 1 (the first evaporation tank A) → No. 4.

[0062] III. Sequence and method of starting and stopping the evaporation tank switch valves.

[0063] According to the aforementioned tank transfer sequence, the earliest tank to stop washing and standby is No. 4 tank, and it starts from No. 4 tank first.

[0064] 1. Valve operation sequence and method for starting No. 4 tank and stopping No. 5 tank:

[0065] Manual operation preparation reminder: Before the tank transfer, the No. 4 tank should be boiled with mixed steam. After boiling the water, open the drain valve, quickly drain the water in the steam chamber, and then quickly close the drain valve and the steam condensate drain ditch valve to prevent air from entering the steam chamber and steam drum. At this time, keep all the valves of the No. 4 tank closed.

[0066] 15 minutes before the tank transfer, close the juice inlet valve E11 of the 5-effect tank in advance and raise the liquid level of the No. 3 tank to facilitate the next step of guiding the sugar juice from the No. 3 tank into the started No. 4 tank.

[0067] After completing the above preparatory work, start the automatic control program for starting Tank No. 4 and stopping Tank No. 5 (automatically control the opening and closing of valves in the following sequential numbers):

[0068] 1) Close the juice inlet valve E11 of Tank No. 5;

[0069] 2) Close the juice outlet valve E12 of Tank No. 5;

[0070] 3) Close the juice passing partition valve D13 of Tank No. 4;

[0071] 4) Open the juice inlet valve D11 of Tank No. 4;

[0072] 5) When the liquid level in Tank No. 4 reaches one-third of the height of the steam drum after juice inlet, open the juice outlet steam valve D12 of Tank No. 4;

[0073] 6) Open the steam condensate discharge valve D15 of Tank No. 4;

[0074] 7) Open the steam condensate rear partition valve D17 of Tank No. 4;

[0075] 8) Open the juice steam three-way valve D1 of Tank No. 4.

[0076] 9) Close the juice steam three-way valve E1 of Tank No. 5;

[0077] 10) Open the heating extraction 4-effect juice steam valve E9;

[0078] 11) Close the heating extraction 4-effect juice steam valve D9;

[0079] 12) Close the juice steam inlet valve E3 of Tank No. 5;

[0080] 13) Close the steam condensate discharge valve E16 of Tank No. 5;

[0081] 14) Close the steam condensate front partition valve E17 of Tank No. 5.

[0082] So far, the process of starting Tank No. 4 and stopping Tank No. 5 has been completed.

[0083] 2. Valve operation sequence and method for starting Tank No. 5 and stopping Tank No. 6:

[0084] Manual operation preparation reminder: Before the tank transfer, boil the water in Tank No. 5 with mixed steam. After boiling the water, open the drain valve, quickly drain the water in the steam chamber completely, and then quickly close the drain valve and the steam condensate drain channel valve to avoid air from entering the steam chamber and the steam drum. At this time, keep all valves of Tank No. 5 closed.

[0085] 15 minutes before the tank transfer, close the juice inlet valve F11 of the 6-effect tank slightly in advance to increase the liquid level of Tank No. 4, which is beneficial for the next step of guiding the sugar juice from Tank No. 4 into the started Tank No. 5.

[0086] After completing the above preparations, start the automatic control program for starting Tank No. 5 and stopping Tank No. 6 (automatically control the opening and closing of valves in the following sequential numbers):

[0087] 1) Close the juice inlet valve F11 of Tank No. 6 (at this time, the pumping of syrup can be temporarily stopped);

[0088] 2) Close the juice outlet valve F12 of Tank No. 6;

[0089] 3) Close the juice passing partition valve E13 of Tank No. 5;

[0090] 4) Open the juice inlet valve E11 of Tank No. 5;

[0091] 5) Open the juice passing partition valve F13 of Tank No. 6;

[0092] 7) When the liquid level in Tank No. 5 reaches one-third of the height of the steam drum after juice inlet, open the juice outlet steam valve E3 of Tank No. 5;

[0093] 8) Open the steam condensate discharge valve E15 of Tank No. 5;

[0094] 9) Open the steam condensate partition valve E17 of Tank No. 5;

[0095] 10) Open the juice-steam three-way valve E1 of Tank No. 5;

[0096] 11) Open the heating extraction valve D9 of the 4th effect;

[0097] 12) Close the heating extraction valve E9 of the 4th effect; (due to fear of vacuum breakage, first transfer the steam of the 4th heating effect and then close the three-way valve of Tank No. 6)

[0098] 13) Close the juice-steam three-way valve F1 of Tank No. 6;

[0099] 14) Close the juice-steam inlet valve F3 of Tank No. 6;

[0100] 15) Close the steam condensate discharge valve F16 of Tank No. 6;

[0101] So far, the process of starting Tank No. 5 and stopping Tank No. 6 has been completed.

[0102] 3. Valve operation sequence and method for starting Tank No. 6 and stopping Tank No. 3:

[0103] Manual operation preparation reminder: Before transferring the tank, the water in Tank No. 6 should be boiled with mixed steam. After boiling the water, open the drain valve, quickly drain the water in the steam chamber completely, and then quickly close the drain valve and the steam condensate drain ditch valve to prevent air from entering the steam chamber and the steam drum. At this time, keep all the valves of Tank No. 6 closed.

[0104] 15 minutes before transferring the tank, close the juice inlet valve E12 of Tank No. 5 slightly in advance and raise the liquid level of Tank No. 5 to facilitate the next step of guiding the sugar juice from Tank No. 5 into the started Tank No. 6.

[0105] After completing the above preparatory work, start to activate the automatic control program for Tank No. 6 and deactivate the automatic control program for Tank No. 3 (automatically control the opening and closing of valves in the following order of numbers):

[0106] 1) Close the juice passing partition valve F13 of Tank No. 6;

[0107] 2) Open the juice inlet valve F11 of Tank No. 6;

[0108] 3) When the liquid level in Tank No. 6 reaches one-third of the steam drum height after juice inlet, open the juice outlet valve F12 of Tank No. 6. (Since Tank No. 5 is in high vacuum at this time, if the vacuum degree of Tank No. 6 is not enough, the syrup cannot smoothly enter Tank No. 6. Therefore, when activating Tank No. 6, the program can not consider the liquid level of the sugar juice in the tank and then open the three-way valve of No. 6 after opening the steam inlet valve of No. 6 juice steam to facilitate the formation of vacuum for juice inlet in Tank No. 6), open the steam inlet valve F3 of the juice steam of Tank No. 6;

[0109] 4) Open the steam condensate discharge valve F15 of Tank No. 6;

[0110] 5) Close the steam condensate rear partition valve E17 of Tank No. 5;

[0111] 6) Open the steam condensate front partition valve E16 of Tank No. 5;

[0112] 7) Open the juice steam three-way valve F1 of Tank No. 6;

[0113] 8) Open the heating extraction 4-effect steam E9;

[0114] 9) Close the heating extraction 4-effect steam D9; (Steps 8 and 9 can be carried out simultaneously, and the conversion of other sugar boiling and heating juice steam is similar. Optimize it further in the next step)

[0115] 10) Close the juice inlet valve C11 of Tank No. 3;

[0116] 11) Close the juice outlet valve C12 of Tank No. 3;

[0117] 12) Open the juice passing partition valve C13 of Tank No. 3;

[0118] 13) Close the juice steam three-way valve C1 of Tank No. 3;

[0119] 14) Open the heating extraction 3-effect steam valve D8;

[0120] 15) Close the heating extraction 3-effect steam valve C8;

[0121] 16) Close the juice steam inlet valve C3 of Tank No. 3;

[0122] 17) Open the steam condensate front partition valve D15 of Tank No. 4;

[0123] 18) Close the steam condensate rear partition valve D17 of Tank No. 4;

[0124] 19) Close the steam condensate valve C15 of Tank No. 3;

[0125] 20) Close the isolating valve C17 after the steam condensate of Tank No. 3;

[0126] Thus, the process of activating Tank No. 6 and deactivating Tank No. 3 is completed.

[0127] 4. Valve operation sequence and method for activating Tank No. 3 and deactivating Tank No. 2:

[0128] Manual operation preparation reminder: Before transferring the tank, Tank No. 3 should be boiled with mixed steam. After boiling the water, open the drain valve, quickly drain the water in the evaporation steam chamber, and then quickly close the drain valve and the steam condensate drain channel valve to prevent air from entering the steam chamber and steam drum. At this time, close all the valves of Tank No. 3.

[0129] Fifteen minutes before transferring the tank, close the juice outlet valve B12 of the second evaporator B to increase the liquid level of the second evaporator B; when the liquid level reaches above one sight glass, open the juice inlet valve C11 to make the sugar juice in the third evaporator reach two-thirds of the steam drum heating surface before the transfer and stop operation of the tank can be carried out.

[0130] After completing the above preparations, start the automatic control program for activating Tank No. 3 and deactivating Tank No. 2 (the automatic control program automatically controls the opening and closing of valves in the following serial numbers):

[0131] 1) Close the juice isolation valve C13 of Tank No. 3;

[0132] 2) Open the juice inlet valve C11 of Tank No. 3;

[0133] 3) When the liquid level in Tank No. 3 reaches one-third of the steam drum height after juice inlet, open the juice steam inlet valve C3 of Tank No. 3;

[0134] 4) Open the steam condensate discharge valve C15 of Tank No. 3;

[0135] 5) Open the isolating valve C16 before the steam condensate of Tank No. 3;

[0136] 6) Open the juice steam three-way valve C1 of Tank No. 3;

[0137] 7) Open the juice outlet valve C12 of Tank No. 3;

[0138] 8) Close the juice steam three-way valve B1 of Tank No. 2;

[0139] 9) Open the juice isolation valve B13 of Tank No. 2;

[0140] 10) Close the juice inlet valve B11 of Tank No. 2;

[0141] 11) Close the juice outlet valve B12 of Tank No. 2;

[0142] 12) Open the 2nd effect steam valve C5 for sugar boiling extraction;

[0143] 13) Close the 2nd effect steam valve B5 for sugar boiling extraction;

[0144] 14) Open the 2nd effect steam valve C7 for heating extraction;

[0145] 15) Close the 2nd effect steam valve B7 for heating extraction;

[0146] 16) Close the juice steam inlet valve B3 of the No. 2 tank;

[0147] 18) Close the 2nd steam condensate discharge valve B15;

[0148] 19) Close the 2nd steam condensate rear isolation valve B17;

[0149] Thus, the process of activating the No. 3 tank and deactivating the No. 2 tank is completed.

[0150] 5. Valve operation sequence and method for activating the No. 2 tank and deactivating the No. 1 tank:

[0151] Manual operation preparation reminder: Before transferring the tank, the No. 2 tank should be boiled with mixed steam. After boiling, open the drain valve, quickly drain the water in the steam chamber, and then quickly close the drain valve and the steam condensate drain ditch valve to prevent air from entering the steam chamber and steam drum. At this time, keep all valves of the No. 2 tank closed.

[0152] Fifteen minutes before transferring the tank, appropriately raise the liquid level of the No. 1 tank in advance to facilitate the transfer of sugar juice from the No. 1 tank to the activated No. 2 tank.

[0153] After completing the above preparations, start the automatic control program for activating the No. 2 tank and deactivating the No. 1 tank (the automatic control program automatically controls the opening and closing of valves in the following serial numbers):

[0154] Before starting the automatic program, the matters that need to be completed manually first: Open the juice inlet valve of the No. 2 tank, and adjust and raise the liquid levels of the No. 1 and No. 3 tanks. When the liquid level of the sugar juice in the No. 2 tank is not less than one-third of the height of the heating tubes (the time is about 20 minutes), the automatic control program can be started:

[0155] 1) Open the juice inlet valve of the No. 2 tank;

[0156] 2) Close the juice passing isolation valve B13 of the No. 2 tank;

[0157] 3) When the liquid level of the sugar juice in the No. 2 tank is not less than one-third of the height of the heating tubes, open the mixed steam inlet valve B2 of the No. 2 tank;

[0158] 4) Open the steam condensate discharge valve B15 of the No. 2 tank;

[0159] 5) Open the steam condensate front isolation valve B16 of the No. 2 tank;

[0160] 6) Open the juice steam three-way valve B1 of Tank No. 2 to 50%;

[0161] 7) Open the juice passing isolation valve A13 of Tank No. 1;

[0162] 8) Close the juice inlet valve A11 of Tank No. 1;

[0163] 9) Close the juice outlet valve A12 of Tank No. 1;

[0164] 10) Close the mixed steam inlet valve A2 of Tank No. 1;

[0165] 11) Close the steam condensate discharge valve A15 of Tank No. 1;

[0166] 12) Fully open the juice steam three-way valve B1 of Tank No. 2;

[0167] 13) Open the sugar boiling extraction 1st effect steam valve B4 of Tank No. 2;

[0168] 14) Close the sugar boiling extraction 1st effect steam valve A4 of Tank No. 1;

[0169] 15) Open the heating extraction 1st effect steam valve B6 of Tank No. 2;

[0170] 16) Close the heating extraction 1st effect steam valve A6 of Tank No. 1;

[0171] Thus, the process of activating Tank No. 2 and deactivating Tank No. 1 is completed.

[0172] 6. Valve operation sequence and method for activating Tank No. 1 and deactivating Tank No. 4:

[0173] Manual operation preparation reminder: Before the tank transfer, Tank No. 1 should be boiled with mixed steam. After boiling, open the drain valve, quickly drain the water in the steam chamber completely, and then quickly close the drain valve and the steam condensate drain ditch valve to prevent air from entering the steam chamber and steam drum. At this time, keep all valves of Tank No. 1 closed.

[0174] 15 minutes before the tank transfer, appropriately raise the liquid levels of Tanks No. 2 and 3 in advance to facilitate the transfer of clear juice into the activated Tank No. 1.

[0175] After completing the above preparatory work, start the automatic control program for activating Tank No. 1 and deactivating Tank No. 4 (the automatic control program automatically controls the opening and closing of valves in the following serial numbers):

[0176] Matters to be completed manually before starting the automatic program: First, appropriately raise the liquid levels of Tanks No. 2 and 3, and then manually open the juice inlet valve of Tank No. 1 appropriately. When the liquid level of the sugar juice entering Tank No. 1 is not less than one-third of the height of the heating tubes (the time is about 20 minutes), the automatic control program can be started:

[0177] 1) Open the juice inlet valve A11 of Tank No. 1;

[0178] 2) Close the juice passing isolation valve A13 of Tank No. 1;

[0179] 3) When the sugar juice enters Tank No. 1 and the liquid level in the heating tubes is not less than one-third of the height, open the mixed steam inlet valve A2 of Tank No. 1;

[0180] 4) Open the juice steam inlet valve B3 of Tank No. 2;

[0181] 5) Open the steam condensate discharge valve A15 of Tank No. 1;

[0182] 6) Close the front steam condensate isolation valve B16 of Tank No. 2;

[0183] 7) Open the rear steam condensate isolation valve B17 of Tank No. 2;

[0184] 8) When the liquid level in Tank No. 1 reaches the normal liquid level at 3 meters from the bottom of the tank, close the mixed steam inlet valve B2 of Tank No. 2;

[0185] 9) Open the sugar boiling extraction first effect steam valve A4;

[0186] 10) Close the sugar boiling extraction first effect steam valve B4;

[0187] 11) Open the heating extraction first effect steam valve A6;

[0188] 12) Close the heating extraction first effect steam valve B6;

[0189] 13) Open the sugar boiling extraction second effect steam valve B5;

[0190] 14) Close the sugar boiling extraction second effect steam valve C5;

[0191] 15) Open the heating extraction second effect steam valve B7;

[0192] 16) Close the heating extraction second effect steam valve C7;

[0193] 17) Close the juice steam three-way valve D1 of Tank No. 4;

[0194] 18) Close the juice inlet valve D11 of Tank No. 4;

[0195] 19) Open the juice passing isolation valve D13 of Tank No. 4;

[0196] 20) Close the juice outlet valve D12 of Tank No. 4;

[0197] 21) Close the steam condensate discharge valve D15 of Tank No. 4;

[0198] 22) Close the front steam condensate isolation valve D16 of Tank No. 4;

[0199] 23) Close the front steam condensate isolation valve E16 of Tank No. 3;

[0200] 24) Open the condensate valve E17 of Tank No. 3 and then cut off the valve.

[0201] Thus, the process of starting up Tank No. 1 and shutting down Tank No. 4 is completed.

[0202] See Figure 1 , the numbers and corresponding names of the valves in the five-effect evaporation device are shown in the following table:

[0203]

[0204] The five-effect evaporation device includes: the first evaporation tank A, the second evaporation tank B, the third evaporation tank C, the fourth evaporation tank D, the fifth evaporation tank E, the sixth standby evaporation tank F, the mixed saturated steam pipe 13, the clear juice conveying pipe 12, the condensate conveying pipe 11, the low-temperature steam conveying pipe 14, the first-effect juice steam conveying pipe 15, the second-effect juice steam conveying pipe 16, the heater heating juice steam conveying pipe 17 and a plurality of supporting valves; the pipeline connection relationships between each tank body and the mixed saturated steam pipe 13, the clear juice conveying pipe 12, the condensate conveying pipe 11, the low-temperature steam conveying pipe 14, the first-effect juice steam conveying pipe 15, the second-effect juice steam conveying pipe 16, the heater heating juice steam conveying pipe 17 are the same as those in the prior art.

[0205] A first mixed steam inlet valve A2 is arranged on the pipeline connecting the first evaporation tank A and the mixed saturated steam pipe 13; a first juice inlet valve A11 is arranged on the pipeline connecting the juice inlet of the first evaporation tank A and the clear juice conveying pipe 12; a first condensate discharge valve A15 is arranged on the pipeline connecting the first evaporation tank A and the condensate conveying pipe 11; a first juice outlet valve A12 is arranged on the pipeline connecting the juice outlet of the first evaporation tank A and the clear juice conveying pipe 12; a first sugar-boiling extraction first-effect juice steam valve A4 is arranged on the pipeline connecting the first evaporation tank A and the first-effect juice steam conveying pipe 15; a first heating extraction first-effect juice steam valve A6 is arranged on the pipeline connecting the first evaporation tank A and the heater heating juice steam conveying pipe 17; a first heating juice steam cut-off valve A10 is arranged on the heater heating juice steam conveying pipe 17; a first juice passing cut-off valve A13 is arranged between the connection points of the branch pipes where the first juice inlet valve A11 and the first juice outlet valve A12 are arranged and the clear juice conveying pipe 12;

[0206] A second steam inlet valve B2 is provided on the pipeline connecting the second evaporation tank B and the first evaporation tank A; a second juice outlet valve B12 is provided on the pipeline connecting the juice outlet of the second evaporation tank B and the clear juice delivery pipe 12; a second juice inlet valve B11 is provided on the pipeline connecting the juice inlet of the second evaporation tank B and the clear juice delivery pipe 12; a second steam condensate discharge valve B15 is provided on the pipeline connecting the second evaporation tank B and the steam condensate delivery pipe 11; second steam condensate pre-isolation valves B16 and second steam condensate post-isolation valves B17 are provided on the steam condensate delivery pipe 11 on both sides of the connection point where the pipeline where the second steam condensate discharge valve B15 is provided is connected to the steam condensate delivery pipe 11; a second juice bypass isolation valve B13 is provided between the connection points of the branches where the second juice inlet valve B11 and the second juice outlet valve B12 are provided and the clear juice delivery pipe 12;

[0207] A second juice-steam inlet valve B3 is provided on the pipeline connecting the second evaporation tank B and the low-temperature steam delivery pipe 14; the exhaust port of the second evaporation tank B is connected to the low-temperature steam delivery pipe 14 through a second juice-steam three-way valve B1; a second sugar-boiling extraction of 1st effect juice-steam valve B4 is provided on the pipeline connecting the second evaporation tank B and the first-effect juice-steam delivery pipe 15; a second heating extraction of 2nd effect juice-steam valve B7 and a second heating juice-steam isolation valve B10 are provided on the pipeline connecting the second evaporation tank B and the heater heating juice-steam delivery pipe 17; the second heating juice-steam isolation valve B10 is provided on the heater heating juice-steam delivery pipe 17;

[0208] A third juice-steam inlet valve C3 is provided on the pipeline connecting the third evaporation tank C and the low-temperature steam delivery pipe 14; a third juice outlet valve C12 is provided on the pipeline connecting the juice outlet of the third evaporation tank C and the clear juice delivery pipe 12; a third juice inlet valve C11 is provided on the pipeline connecting the juice inlet of the third evaporation tank C and the clear juice delivery pipe 12; a third steam condensate discharge valve C15 is provided on the pipeline connecting the third evaporation tank C and the steam condensate delivery pipe 11; third steam condensate pre-isolation valves C16 and third steam condensate post-isolation valves C17 are provided on the steam condensate delivery pipe 11 on both sides of the connection point where the pipeline where the third steam condensate discharge valve C15 is provided is connected to the steam condensate delivery pipe 11; a third juice bypass isolation valve C13 is provided between the connection points of the branches where the third juice inlet valve C11 and the third juice outlet valve C12 are provided and the clear juice delivery pipe 12;

[0209] The third evaporation tank C is connected to the low-temperature steam delivery pipe 14 through a third juice-steam three-way valve C1; a third sugar-boiling extraction of 2nd effect juice-steam valve C5 is provided on the pipeline connecting the third evaporation tank C and the second-effect juice-steam delivery pipe 16; the section of the low-temperature steam delivery pipe 14 between the third juice-steam three-way valve C1 and the third sugar-boiling extraction of 2nd effect juice-steam valve C5 is connected to the heater heating juice-steam delivery pipe 17, and a third heating extraction of 2nd effect juice-steam valve C7 is provided on the connecting pipeline;

[0210] The third heating juice steam isolation valve C10, the fourth heating juice steam isolation valve D10, the fifth heating juice steam isolation valve E10, and the sixth heating juice steam isolation valve F10 are arranged at intervals on the heating juice steam conveying pipe 17 of the heater.

[0211] On the low-temperature steam conveying pipe 14, one ends of the pipelines where the third heating and extracting 3-effect juice steam valve C8 and the fourth heating and extracting 3-effect juice steam valve D8 are arranged are respectively arranged at both ends of the fourth juice steam three-way valve D1, and the other ends of the pipelines where the third heating and extracting 3-effect juice steam valve C8 and the fourth heating and extracting 3-effect juice steam valve D8 are arranged are communicated with the heating juice steam conveying pipe 17 of the heater;

[0212] On the pipeline where the fourth evaporation tank D is communicated with the low-temperature steam conveying pipe 14, a fourth juice steam inlet valve D3 is arranged; on the pipeline where the juice outlet of the fourth evaporation tank D is communicated with the clear juice conveying pipe 12, a fourth juice outlet valve D12 is arranged; on the pipeline where the juice inlet of the fourth evaporation tank D is communicated with the clear juice conveying pipe 12, a fourth juice inlet valve D11 is arranged; on the pipeline where the fourth evaporation tank D is communicated with the steam condensate conveying pipe 11, a fourth steam condensate discharge valve D15 is arranged; on the steam condensate conveying pipe 11 on both sides of the connection point where the pipeline where the fourth steam condensate discharge valve D15 is arranged is communicated with the steam condensate conveying pipe 11, a fourth steam condensate front isolation valve D16 and a fourth steam condensate rear isolation valve D17 are arranged; a fourth juice passing isolation valve D13 is arranged between the connection points of the branches where the fourth juice inlet valve D11 and the fourth juice outlet valve D12 are arranged and the clear juice conveying pipe 12;

[0213] On the pipeline where the fifth evaporation tank E is communicated with the low-temperature steam conveying pipe 14, a fifth juice steam inlet valve E3 is arranged; on the pipeline where the juice outlet of the fifth evaporation tank E is communicated with the clear juice conveying pipe 12, a fifth juice outlet valve E12 is arranged; on the pipeline where the juice inlet of the fifth evaporation tank E is communicated with the clear juice conveying pipe 12, a fifth juice inlet valve E11 is arranged; on the pipeline where the fifth evaporation tank E is communicated with the steam condensate conveying pipe 11, a fifth steam condensate discharge valve E15 is arranged; on the steam condensate conveying pipe 11 on both sides of the connection point where the pipeline where the fifth steam condensate discharge valve E15 is arranged is communicated with the steam condensate conveying pipe 11, a fifth steam condensate front isolation valve E16 and a fifth steam condensate rear isolation valve E17 are arranged; a fifth juice passing isolation valve E13 is arranged between the connection points of the branches where the fifth juice inlet valve E11 and the fifth juice outlet valve E12 are arranged and the clear juice conveying pipe 12; a fifth syrup tank balance valve E14 is arranged on the balance pipeline of the fifth evaporation tank E;

[0214] On the low-temperature steam conveying pipe 14, one ends of the pipelines where the fourth heating and extracting 4-effect juice steam valve D9 and the fifth heating and extracting 4-effect juice steam valve E9 are arranged are respectively arranged at both ends of the fifth juice steam three-way valve E1, and the other ends of the pipelines where the fourth heating and extracting 4-effect juice steam valve D9 and the fifth heating and extracting 4-effect juice steam valve E9 are arranged are communicated with the heating juice steam conveying pipe 17 of the heater;

[0215] On the pipeline connecting the sixth standby evaporator F to the low-temperature steam delivery pipe 14, a sixth juice steam inlet valve F3 is provided; on the pipeline connecting the juice outlet of the sixth standby evaporator F to the clear juice delivery pipe 12, a sixth juice outlet valve F12 is provided; on the pipeline connecting the juice inlet of the sixth standby evaporator F to the clear juice delivery pipe 12, a sixth juice inlet valve F11 is provided; on the pipeline connecting the sixth standby evaporator F to the steam condensate delivery pipe 11, a sixth steam condensate discharge valve F15 is provided; on the steam condensate delivery pipe 11 on both sides of the connection point where the pipeline where the sixth steam condensate discharge valve F15 is provided is connected to the steam condensate delivery pipe 11, a sixth steam condensate front isolation valve F16 and a sixth steam condensate rear isolation valve F17 are provided; between the connection points of the branches where the sixth juice inlet valve F11 and the sixth juice outlet valve F12 are connected to the clear juice delivery pipe 12, a sixth juice passing isolation valve F13 is provided; a sixth syrup tank balance valve F14 is provided on the balance pipeline of the sixth standby evaporator F; the sixth juice inlet valve F11 and the low-temperature steam delivery pipe 14 are connected through a sixth juice steam three-way valve F1 pipeline.

[0216] Before controlling by the above method: For the normal startup and shutdown of the evaporator, the operation of all valves must be commanded and distributed by 3 - 4 operators in sequence according to the startup and shutdown safety operation procedures, and the valves are switched on and off one by one. The labor intensity is high, there are relatively large potential safety hazards, the liquid level control of the evaporator is unstable, the syrup Brix fluctuates greatly. The original 65Bx° syrup drops to about 50Bx° in 15 - 20 minutes. The recovery of normal production speed is slow, which cannot meet the normal production requirements, prolongs the cooking and residence time for the subsequent process sections to process materials, increases the sugar color value by 5 - 10IU, affects the product quality, also causes invisible loss of sugar, reduces the recovery, increases the cost, and reduces the economic benefits of the enterprise.

[0217] After controlling by the above method: For the normal startup and shutdown of the evaporator, the labor intensity of the operators can be reduced. Only 1 - 2 people are needed to operate according to the startup and shutdown safety operation procedures. It only takes 5 - 8 minutes to resume the normal operation of the evaporator and the smooth progress of production. The Brix of the 65Bx° syrup can maintain a decrease range of 3 - 5Bx° within a short time and remain at 60 - 62Bx°. The cooking time and residence time for the subsequent process sections are within the controllable normal range, and the color value is controlled below 100IU, effectively ensuring the product quality and recovery, and laying a solid foundation for the enterprise to improve the sugar yield, reduce the production cost, and increase the economic benefits.

[0218] Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A control method for a single-valve sequential-switching smooth automatic start-stop evaporation tank, characterized in that This method is used in a five - effect evaporation device, which includes: the first evaporation tank A, the second evaporation tank B, the third evaporation tank C, the fourth evaporation tank D, the fifth evaporation tank E, the sixth standby evaporation tank F, a mixed saturated steam pipe (13), a clear juice conveying pipe (12), a steam condensate conveying pipe (11), a low - temperature steam conveying pipe (14), a first - effect juice steam conveying pipe (15), a second - effect juice steam conveying pipe (16), a heater heating juice steam conveying pipe (17) and multiple supporting valves; The first evaporation tank A, the second evaporation tank B, the third evaporation tank C, the fourth evaporation tank D, the fifth evaporation tank E, and the sixth standby evaporation tank F are respectively connected to the mixed saturated steam pipe (13), the clear juice conveying pipe (12), the steam condensate conveying pipe (11), the low - temperature steam conveying pipe (14), the first - effect juice steam conveying pipe (15), the second - effect juice steam conveying pipe (16), and the heater heating juice steam conveying pipe (17) through pipelines; supporting valves are arranged on the connecting pipelines; After the preparation for tank transfer is completed, operate to start and stop each evaporation tank in the following order: Step S1: Enable the fourth evaporation tank D, disable the fifth evaporation tank E. After evaporation operation in the fourth evaporation tank D, enable the fifth evaporation tank E, disable the sixth standby evaporation tank F. After evaporation operation in the fifth evaporation tank E, enable the sixth standby evaporation tank F, disable the third evaporation tank C, and then perform evaporation operation in the sixth standby evaporation tank F; Step S2: Enable the third evaporation tank C, disable the second evaporation tank B. After evaporation operation in the third evaporation tank C, enable the second evaporation tank B, disable the third evaporation tank C. After evaporation operation in the second evaporation tank B, enable the first evaporation tank A, disable the fourth evaporation tank D. After evaporation operation in the first evaporation tank A, return to Step S1.

2. The single-valve sequential switch smooth automatic rotation-stop evaporation tank control method according to claim 1, characterized in that "Enable the fourth evaporation tank D, disable the fifth evaporation tank E" includes the following operations: Step S111: After draining water and gas from the fourth evaporation tank D after cooking and disinfection, close all valves connected to the fourth evaporation tank D. 15 minutes before tank transfer, throttle down the juice outlet valve C12 of the third evaporation tank C to increase the liquid level of the third evaporation tank C; Step S112: Close the juice inlet valve E11 of the fifth evaporation tank E, close the juice outlet valve E12 of the fifth evaporation tank E, close the juice - passing isolation valve D13 of the fourth evaporation tank D, open the juice inlet valve D11 of the fourth evaporation tank D. When the liquid level in the fourth evaporation tank D reaches one - third of the steam drum height after juice inlet, open the juice inlet steam valve D3 of the fourth evaporation tank D, open the steam condensate discharge valve D15 of the fourth evaporation tank D, open the steam condensate rear isolation valve D17 of the fourth evaporation tank D, and open the juice steam three - way valve D1 of the fourth evaporation tank D; Step S113: Close the juice steam three - way valve E1 of the fifth evaporation tank E, open the heating extraction 4 - effect juice steam valve E9 of the fifth evaporation tank E, close the heating extraction 4 - effect juice steam valve D9 of the fourth evaporation tank D, close the juice steam inlet valve E3 of the fifth evaporation tank E, close the steam condensate discharge valve E16 of the fifth evaporation tank E, and close the steam condensate front isolation valve E17 of the fifth evaporation tank E.

3. The single-valve sequential switching smooth automatic rotation-stop evaporation tank control method according to claim 1, characterized in that, "Enable the fifth evaporation tank E, disable the sixth standby evaporation tank F" includes the following operations: Step S121: After draining water and gas from the fifth evaporator E after steam sterilization, close all valves on the pipeline connected to the fifth evaporator E. 15 minutes before transferring the tank, throttle down the juice outlet valve D12 of the fourth standby evaporator D to increase the liquid level of the fourth evaporator D. Step S122: Close the juice inlet valve F11 of the sixth standby evaporator F, temporarily stop pumping syrup, close the juice outlet valve F12 of the sixth standby evaporator F, close the juice passing partition valve E13 of the fifth evaporator E, open the juice inlet valve E11 of the fifth evaporator E, open the juice passing partition valve F13 of the sixth standby evaporator F. When the liquid level of the fifth evaporator E reaches one-third of the steam drum height after juice inlet, open the juice inlet steam valve E3 of the fifth evaporator E. Step S123: Open the steam condensate discharge valve E15 of the fifth evaporator E, open the steam condensate partition valve E17 of the fifth evaporator E, open the juice steam three-way valve E1 of the fifth evaporator E, open the heating extraction 4-effect valve D9, close the heating extraction 4-effect valve E9, close the juice steam three-way valve F1 of the sixth standby evaporator F, close the juice steam inlet valve F3 of the sixth standby evaporator F, close the steam condensate discharge valve F16 of the sixth standby evaporator F.

4. The single-valve sequential switch smooth automatic start-stop evaporation tank control method according to claim 1, characterized in that, "Enable the sixth standby evaporator F and disable the third evaporator C" includes the following operations: Step S131: After draining water and gas from the sixth standby evaporator F after steam sterilization, close all valves on the pipeline connected to the sixth standby evaporator F. 15 minutes before transferring the tank, throttle down the juice outlet valve B12 of the second evaporator B to increase the liquid level of the second evaporator B. Step S132: Close the juice passing partition valve F13 of the sixth standby evaporator F, open the juice inlet valve F11 of the sixth standby evaporator F. When the liquid level of the sixth standby evaporator F reaches one-third of the steam drum height after juice inlet, open the juice steam inlet valve F of the sixth standby evaporator F, open the steam condensate discharge valve F15 of the sixth standby evaporator F, close the steam condensate rear partition valve E17 of the fifth evaporator E, open the steam condensate front partition valve E16 of the fifth evaporator E, open the juice steam three-way valve F1 of the sixth standby evaporator F, open the heating extraction 4-effect steam valve E9, close the heating extraction 4-effect steam valve D9, close the juice inlet valve C11 of the third evaporator C. Step S133: Close the juice outlet valve C12 of the third evaporator C, open the juice passing partition valve C13 of the third evaporator C, close the juice steam three-way valve C1 of the third evaporator C, open the fourth heating extraction 3-effect steam valve D8, close the third heating extraction 3-effect steam valve C8, close the third juice inlet steam valve C11 of the third evaporator C, open the steam condensate front partition valve D15 of the fourth evaporator D, close the steam condensate rear partition valve D17 of the fourth evaporator D, close the steam condensate valve C15 of the third evaporator C, close the steam condensate rear partition valve C17 of the third evaporator C.

5. The single-valve sequential switch stable automatic rotation stop evaporation tank control method according to claim 1, characterized in that, "Enable the third evaporator C and disable the second evaporator B" includes the following operations. Step S211: After draining water and gas from the third evaporator C after steam sterilization, close all valves on the pipeline connected to the third evaporator C. 15 minutes before tank transfer, throttle down the juice outlet valve B12 of the second evaporator B to increase the liquid level of the second evaporator B. When the liquid level reaches above one sight glass, open the juice inlet valve C11 so that the sugar juice in the third evaporator reaches two-thirds of the steam drum heating surface before the tank transfer and stop operation can be carried out. Step S212: Close the juice passing partition valve C13 of the third evaporator C, open the juice inlet valve C11 of the third evaporator C. After the third evaporator C is filled with juice and the liquid level reaches one-third of the steam drum height, open the juice steam inlet valve C3 of the third evaporator C, open the steam condensate discharge valve C15 of the third evaporator C, open the steam condensate front partition valve C16 of the third evaporator C, open the juice steam three-way valve C1 of the third evaporator C, open the juice outlet valve C12 of the third evaporator C, close the juice steam three-way valve B1 of the second evaporator B, open the juice passing partition valve B13 of the second evaporator B, and close the juice inlet valve B11 of the second evaporator B; Step S213: Close the juice outlet valve C12 of the third evaporator C, open the juice passing partition valve C13 of the third evaporator C, close the juice steam three-way valve C1 of the third evaporator C, open the heating extraction 3-effect steam valve D8 of the fourth evaporator D, close the heating extraction 3-effect steam valve C8 of the third evaporator C, close the inlet steam valve C3 of the third evaporator C, open the steam condensate front partition valve D15 of the fourth evaporator D, close the steam condensate rear partition valve D17 of the fourth evaporator D, close the steam condensate valve C15 of the third evaporator C, and close the steam condensate rear partition valve C17 of the third evaporator C.

6. The single-valve sequential switch smooth automatic rotation-stop evaporation tank control method according to claim 1, characterized in that "Enable the second evaporator B and disable the first evaporator A" includes the following operations: Step S221: After draining water and gas from the second evaporator B after steam sterilization, close all valves on the pipeline connected to the second evaporator B. 15 minutes before tank transfer, throttle down the juice outlet valve A12 of the first evaporator A to increase the liquid level of the first evaporator A. When the liquid level reaches above one sight glass, open the juice inlet valve B11 so that the sugar juice in the second evaporator reaches two-thirds of the steam drum heating surface before the tank transfer and stop operation can be carried out. Step S222: Open the juice inlet valve B11 of the second evaporator B, close the juice passing partition valve B13 of the second evaporator B. When the sugar juice enters the second evaporator B and the liquid level in the heating tubes is not less than one-third of the height, open the mixed steam inlet valve B2 of the second evaporator B, open the steam condensate discharge valve B15 of the second evaporator B, open the steam condensate front partition valve B16 of the second evaporator B, open the juice steam three-way valve B1 of the second evaporator B to 50%, open the juice passing partition valve A13 of the first evaporator A, and close the juice inlet valve A11 of the first evaporator A; Step S223: Close the juice outlet valve A12 of the first evaporator A, close the mixed steam inlet valve A2 of the first evaporator A, close the steam condensate discharge valve A15 of the first evaporator A, fully open the juice steam three-way valve B1 of the second evaporator B, open the sugar boiling extraction 1st effect steam valve B4 of the second evaporator B, close the sugar boiling extraction 1st effect steam valve A4 of the first evaporator A, open the heating extraction 1st effect steam valve B6 of the second evaporator B, and close the heating extraction 1st effect steam valve A6 of the first evaporator A.

7. The single-valve sequential switch smooth automatic transfer and stop evaporation tank control method according to claim 1, characterized in that, "Enable the first evaporator A and disable the fourth evaporator D" includes the following operations: Step S231: After draining water and gas from the first evaporator A after cooking and disinfection, close all valves on the pipeline connected to the first evaporator A. Close the juice outlet valve C12 of the second evaporator B 15 minutes before the tank transfer to increase the liquid level of the second evaporator B; when the liquid level reaches above one sight glass, open the juice inlet valve A11 to make the sugar juice in the first evaporator reach two-thirds of the steam drum heating surface before the tank transfer and stop operation can be carried out. Step S232: Open the juice inlet valve A11 of the first evaporator A, close the juice passing partition valve A13 of the first evaporator A. When the sugar juice enters the first evaporator A and the liquid level is not less than one-third of the height of the heating tubes, open the mixed steam inlet valve A2 of the first evaporator A, open the juice steam inlet valve B3 of the second evaporator B, open the steam condensate discharge valve A15 of the first evaporator A, close the steam condensate front partition valve B16 of the second evaporator B, open the steam condensate rear partition valve B17 of the second evaporator B. When the liquid level in the second evaporator B reaches the normal liquid level of one sight glass at a position 3 meters above the bottom of the tank, close the mixed steam inlet valve B2 of the second evaporator B, open the sugar boiling extraction 1st effect steam valve A4 of the first evaporator A, close the sugar boiling extraction 1st effect steam valve B4 of the second evaporator B, open the heating extraction 1st effect steam valve A6 of the first evaporator A, and close the heating extraction 1st effect steam valve B6 of the second evaporator B; Step S233: Open the sugar boiling extraction 2nd effect steam valve B5 of the second evaporator B, close the sugar boiling extraction 2nd effect steam valve C5 of the third evaporator C, open the heating extraction 2nd effect steam valve B7 of the second evaporator B, close the heating extraction 2nd effect steam valve C7 of the third evaporator C, close the juice steam three-way valve D1 of the fourth evaporator D, close the juice inlet valve D11 of the fourth evaporator D, open the juice passing partition valve D13 of the fourth evaporator D, close the juice outlet valve D12 of the fourth evaporator D, close the steam condensate discharge valve D15 of the fourth evaporator D, close the steam condensate front partition valve D16 of the fourth evaporator D, close the steam condensate front partition valve E16 of the third evaporator C, and open the steam condensate rear partition valve E17 of the third evaporator C.

8. The single-valve sequential switching smooth automatic rotation stop evaporation tank control method according to claim 1, characterized in that, A first steam inlet valve A2 is provided on the pipeline connecting the first evaporation tank A and the mixed saturated steam pipe 13; a first juice inlet valve A11 is provided on the pipeline connecting the juice inlet of the first evaporation tank A and the clarified juice conveying pipe 12; a first condensate discharge valve A15 is provided on the pipeline connecting the first evaporation tank A and the condensate conveying pipe 11; a first juice outlet valve A12 is provided on the pipeline connecting the juice outlet of the first evaporation tank A and the clarified juice conveying pipe 12; a first sugar boiling 1st effect juice steam valve A4 is provided on the pipeline connecting the first evaporation tank A and the first effect juice steam conveying pipe 15; a first heating 1st effect juice steam valve A6 is provided on the pipeline connecting the first evaporation tank A and the heater heating juice steam conveying pipe 17; a first heating juice steam isolation valve A10 is provided on the heater heating juice steam conveying pipe 17; a first juice passing isolation valve A13 is provided between the connection points of the branch pipes provided with the first juice inlet valve A11 and the first juice outlet valve A12 and the clarified juice conveying pipe 12.

9. The single-valve sequential-switching stable automatic rotation-stop evaporation tank control method according to claim 1, wherein A second steam inlet valve B2 is provided on the pipeline connecting the second evaporation tank B and the first evaporation tank A; a second juice outlet valve B12 is provided on the pipeline connecting the juice outlet of the second evaporation tank B and the clarified juice conveying pipe 12; a second juice inlet valve B11 is provided on the pipeline connecting the juice inlet of the second evaporation tank B and the clarified juice conveying pipe 12; a second condensate discharge valve B15 is provided on the pipeline connecting the second evaporation tank B and the condensate conveying pipe 11; a second condensate front isolation valve B16 and a second condensate rear isolation valve B17 are provided on the condensate conveying pipe 11 on both sides of the connection point where the pipeline where the second condensate discharge valve B15 is provided is connected to the condensate conveying pipe 11; a second juice passing isolation valve B13 is provided between the connection points of the branch pipes provided with the second juice inlet valve B11 and the second juice outlet valve B12 and the clarified juice conveying pipe 12.

10. The single-valve sequential switching smooth automatic rotation stop evaporation tank control method according to claim 1, characterized in that, A third juice steam inlet valve C3 is provided on the pipeline connecting the third evaporation tank C and the low-temperature steam conveying pipe 14; a third juice outlet valve C12 is provided on the pipeline connecting the juice outlet of the third evaporation tank C and the clarified juice conveying pipe 12; a third juice inlet valve C11 is provided on the pipeline connecting the juice inlet of the third evaporation tank C and the clarified juice conveying pipe 12; a third condensate discharge valve C15 is provided on the pipeline connecting the third evaporation tank C and the condensate conveying pipe 11; a third condensate front isolation valve C16 and a third condensate rear isolation valve C17 are provided on the condensate conveying pipe 11 on both sides of the connection point where the pipeline where the third condensate discharge valve C15 is provided is connected to the condensate conveying pipe 11; a third juice passing isolation valve C13 is provided between the connection points of the branch pipes provided with the third juice inlet valve C11 and the third juice outlet valve C12 and the clarified juice conveying pipe 12.

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