Automatic adjusting method of filtering and blowback device system

Abstract

The invention provides an automatic adjusting method of a filtering and blowback device system. The filtering and blowback device system comprises a control module, a blowback device system and at least one filtering device, the automatic adjusting method comprises the following steps: acquiring a filtering coefficient of a filtering device and operation data of a reaction device, and feeding back to a control module; the operation data comprises feeding load, operation time and pressure difference; evaluating the filtering coefficient and the operation data so as to guide and adjust the blowback parameters of the blowback device system; the blowback parameters comprise single-time blowback time, interval time of adjacent blowback and blowback pressure. According to the invention, full-automatic control of a filtering and back-blowing device system is realized, so that flux attenuation of a product produced liquid is maintained at a low level, the operation cycle of a filtering device is prolonged, and the operation cycle of a reaction device and the yield of a single-kettle reaction device are further improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of filtering devices, and relates to an automatic adjustment method of a filtering backflushing device system. BACKGROUND

[0002] Candle filters are widely used in fields such as chemical industry, food processing, pharmaceutical industry, water treatment and air purification. They can be designed in different sizes and shapes to meet different filtration requirements and flow rates. Candle filters use the pore structure of the filter medium to intercept impurities in the fluid. When the fluid passes through the filter, larger particles are intercepted on the surface of the medium, while smaller particles may penetrate into the interior of the medium. As the filtration process proceeds, impurities accumulate on the surface of the medium, forming a filter cake, which is not conducive to improving the filtration efficiency.

[0003] Taking the preparation of 1,4-butyne diol (BYD) by acetylene aldehyde method as an example, acetylene, formaldehyde and catalyst gas-liquid-solid three-phase realize continuous reaction in a slurry bed, and the crude BYD generated by the reaction and unreacted formaldehyde are filtered out through the filter cloth on the built-in candle filter, and the catalyst particles are intercepted in the reactor. The filtering precision of the candle filter cloth is 5-10 μm, and as the running period of the reactor is prolonged, polyacetylene, polyformaldehyde and polyacetal polymers are inevitably generated in the reactor, the overall viscosity of the reaction slurry increases, the product liquid filtering performance gradually weakens, and catalyst accumulation occurs in some areas. The bottom layer of catalyst is quickly deactivated because it cannot contact acetylene gas, resulting in poor overall reaction effect.

[0004] To avoid the accumulation of filter cake layer on the filter cloth of the candle filter, high-pressure nitrogen gas is used as the power in the prior art to blow part of the crude BYD back into the reactor, the filter cloth surface catalyst layer is dispersed by the backflushing liquid, the filter cake layer is re-dispersed, and the real-time updating of the filter cake layer on the filter cloth surface is realized. The filter cloth is usually made of aramid material, and the overall blow mechanical strength of the filter cloth is limited due to the wear and tear of the filter cloth sewing process and the filter cloth assembly process. At the end of the reaction operation, the filtering performance is attenuated, and the backflushing pressure and frequency need to be adjusted in time. At present, the adjustment mainly relies on the experience of the operator, and there are problems such as unreasonable backflushing parameter setting and untimely backflushing parameter adjustment, which easily causes filter cloth damage. The filter cloth damage rate at the end of the operation is 30-46%, once a candle filter filter cloth is damaged, the filtering load of the remaining candle filters increases, increasing the risk of filter cloth damage, and the damaged filter cloth causes a large amount of catalyst to enter the produced liquid, and the catalyst enters the backflushing liquid, aggravating the filter cloth blockage. In addition, when the catalyst enters the produced liquid and then enters the downstream BYD rectification system, the catalyst will aggravate the generation of polymers in the BYD rectification tower.

[0005] In summary, the automatic adjustment method of the filter backflushing overcomes the drawbacks of relying on the operator's experience for adjustment, reduces the operation risk of personnel operation, and is a technical problem that needs to be solved by the technical personnel in the field. SUMMARY

[0006] The purpose of the present application is to provide an automatic adjustment method of a filter backflushing device system, which realizes full-automatic control of the filter backflushing device system, maintains a low level of product production liquid flux attenuation, prolongs the operation cycle of the filter device, and further improves the operation cycle of the reaction device and the yield of the single-pot reaction device.

[0007] To achieve the purpose of the present application, the following technical solutions are adopted:

[0008] The present application provides an automatic adjustment method of a filter backflushing device system, which comprises a control module, a backflushing device system and at least one filter device.

[0009] The automatic adjustment method comprises:

[0010] The filter coefficient of the filter device and the operation data of the reaction device are obtained and fed back to the control module; the operation data includes feed load, operation time and pressure difference;

[0011] The filter coefficient and the operation data are evaluated to guide the adjustment of the backflushing parameters of the backflushing device system; the backflushing parameters include single backflushing time, interval time of adjacent backflushing and backflushing pressure.

[0012] The automatic adjustment method provided by the present application obtains the filter coefficient of the filter device and the operation data of the reaction device, feeds back to the control module, evaluates the filter coefficient and the operation data first, and then guides the adjustment of the backflushing parameters of the backflushing device system, so that the filter flux of the filter device is maintained within a certain range, the problems of invalid backflushing of filter cloth and untimely backflushing are avoided, the filter cloth plugging problem caused by backflushing is alleviated, the mechanical strength of the filter cloth at the end of the reaction device operation is guaranteed, the operation cycle of the filter device is prolonged, and the normal production of the product production liquid is maintained; the automatic adjustment method reduces the replacement frequency of the filter cloth of the filter device, reduces the production cost, reduces the labor intensity of the operator, prolongs the operation time of the reaction device, reduces the number of system shutdown, and improves the yield of the single-pot reaction device.

[0013] As a preferred technical solution of the present application, the control module is used for automatic control of the filter backflushing device system.

[0014] In the present application, the filter coefficient of the filter device and the feed load, operation time and pressure difference of the reaction device are controlled in series by the control module, and the automatic control of the backflushing process is realized, and the fluctuation is reduced.

[0015] Preferably, the back flushing device system comprises a gas storage tank and a back washing liquid tank connected in sequence.

[0016] In the present application, the gas in the gas storage tank comprises nitrogen.

[0017] Preferably, a first pressure sensor is arranged on the gas storage tank.

[0018] In the present application, the first pressure sensor is used to monitor the pressure in the gas storage tank.

[0019] Preferably, a first valve is arranged on the pipeline connecting the back washing liquid tank and the gas storage tank.

[0020] In the present application, the gas is pressurized through the first valve, and then the back washing liquid is back flushed into the filter device, the filter cake layer on the filter cloth is renewed, and the continuous production of the reaction liquid is ensured.

[0021] Preferably, a liquid level sensor is arranged on the back washing liquid tank.

[0022] In the present application, the liquid level sensor is used to monitor the liquid level drop of the back washing liquid tank after single back flushing, which is used as the filtration flux of the filter device.

[0023] Preferably, the filter device comprises a candle filter device.

[0024] Preferably, the filter device is arranged in the interior of the reaction device.

[0025] Preferably, the filter device is respectively and independently connected with a product tank and a back washing liquid tank.

[0026] In the present application, the filter device is respectively and independently connected with the product tank and the back washing liquid tank through a three-way valve.

[0027] Preferably, a second pressure sensor is arranged on the reaction device.

[0028] In the present application, the second pressure sensor is used to monitor the pressure in the reaction device.

[0029] Preferably, a third pressure sensor is arranged on the pipeline connecting the reaction device and the product tank.

[0030] In the present application, the third pressure sensor is used to monitor the pressure of the production pipe of the reaction device.

[0031] As a preferred technical solution of the present application, the filtration coefficient is calculated by using formula (I):

[0032]

[0033] wherein, is the filtration coefficient, Q is the average backflush flux of the filter device (%), ΔP1 is the backflush pressure difference (kPa), P1 is the backflush pressure (kPa), and P2 is the pressure of the reaction device (kPa).

[0034] In the present application, all pressures are gauge pressures.

[0035] Preferably, the average backflush flux of the filter device is 0-15%, for example, it can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, or 14%, etc., but not only limited to the listed values, other values not listed in the value range are also applicable.

[0036] Preferably, the filtration coefficient of the filter device is 0-1, for example, it can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9, etc., but not only limited to the listed values, other values not listed in the value range are also applicable.

[0037] As a preferred technical solution of the present application, the pressure difference is calculated using formula (II):

[0038] ΔP2 = P3 - P2 (II)

[0039] wherein, P2 is the pressure of the reaction device (kPa), and P3 is the pressure of the production pipe of the reaction device (kPa).

[0040] Preferably, the pressure difference is 0-140 kPa, for example, it can be 10 kPa, 20 kPa, 30 kPa, 40 kPa, 50 kPa, 60 kPa, 70 kPa, 80 kPa, 90 kPa, 100 kPa, 110 kPa, 120 kPa, or 130 kPa, etc., but not only limited to the listed values, other values not listed in the value range are also applicable.

[0041] As a preferred technical solution of the present application, the evaluation method specifically includes:

[0042] Based on the filtration coefficient of the filter device as the first input variable, the feed load of the reaction device as the second input variable, the running time of the reaction device as the third input variable, and the pressure difference of the reaction device as the fourth input variable, the weights of the input variables are determined and the filtration performance decay value is calculated, the backflush parameters of the backflush device system are adjusted according to the change of the filtration performance decay value, and the optimal backflush parameters are output after iterative calculation.

[0043] In the present application, the filter performance attenuation value is calculated according to the judgment of the control module after calculating the filter coefficient and the pressure difference data, combined with the running time and the feed load of the reaction device, and then the backflush parameters of the backflush device system are adjusted according to the change of the filter performance attenuation value, and the optimal backflush parameters are output after iterative calculation.

[0044] As a preferred technical solution of the present application, the weights of the input variables are determined by using the entropy weight method.

[0045] Preferably, the filter performance attenuation value is calculated by using formula (III):

[0046]

[0047] Wherein, H is the filter performance attenuation value, B i is the input variable n, and B1 represents the filter coefficient of the filter device, B2 represents the feed load of the reaction device, B3 represents the running time of the reaction device, B4 represents the pressure difference of the reaction device, C i is the proportion of the i-th input variable to the filter performance attenuation value.

[0048] Preferably, the value of C1 is 20-70%, for example, it can be 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60% or 65%, etc., but not limited to the listed values, other values not listed in the value range are also applicable.

[0049] Preferably, the value of C2 is 0-80%, for example, it can be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70% or 75%, etc., but not limited to the listed values, other values not listed in the value range are also applicable.

[0050] Preferably, the value of C3 is 0-50%, for example, it can be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40% or 45%, etc., but not limited to the listed values, other values not listed in the value range are also applicable.

[0051] Preferably, the value of C4 is 20-90%, for example, it can be 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80% or 85%, etc., but not limited to the listed values, other values not listed in the value range are also applicable.

[0052] As a preferred technical solution of the present application, the way of adjusting the backflush parameters of the backflush device system according to the change of the filter performance attenuation value includes the following cases:

[0053] When -1< ΔH≤0.05, triggering adjustment of the interval time of adjacent backflushes; or

[0054] When 0.05< ΔH≤0.5, triggering adjustment of the interval time of adjacent backflushes and the backflush pressure; or

[0055] When 0.5< ΔH≤1, triggering adjustment of the single backflush time, the interval time of adjacent backflushes and the backflush pressure;

[0056] Wherein, ΔH=H m+1 -H m , m≥1, and the update frequency of m and m+1 is ≤8h.

[0057] As a preferred technical solution of the present application, the single backflush time is calculated using formula (IV):

[0058]

[0059] Wherein, t is the single backflush time (s), and F is the feed load of the reaction device (%).

[0060] Preferably, the single backflush time is 1-10s, for example, it can be 2s, 3s, 4s, 5s, 6s, 7s, 8s or 9s, etc., but not only limited to the listed values, other values not listed within the value range are also applicable.

[0061] As a preferred technical solution of the present application, the interval time of adjacent backflushes is calculated using formula (V):

[0062]

[0063] Wherein, T is the interval time of adjacent backflushes (s), T0 is the interval time of initial backflush (s), F is the feed load of the reaction device (%), and d is the operation time of the reaction device.

[0064] Preferably, the interval time of adjacent backflushes is 50-2000s, for example, it can be 100s, 300s, 500s, 700s, 1000s, 1200s, 1500s, 1700s or 1900s, etc., but not only limited to the listed values, other values not listed within the value range are also applicable.

[0065] As a preferred technical solution of the present application, the backflush pressure is calculated using formula (VI):

[0066]

[0067] Wherein, P4 is the backflush pressure adjustment value (kPa).

[0068] Preferably, the backflushing pressure is 55-120 kPa, for example, it can be 60 kPa, 65 kPa, 70 kPa, 75 kPa, 80 kPa, 85 kPa, 90 kPa, 95 kPa, 100 kPa, 105 kPa, 110 kPa or 115 kPa, etc., but not limited to the listed values, other values not listed in the value range are also applicable.

[0069] In the present application, the single backflushing time, the interval time T of adjacent backflushing and the backflushing pressure P4 are adjusted by adjusting the standby pressure in the gas storage tank and / or the frequency of the first valve.

[0070] Compared with the prior art, the present application has the following beneficial effects:

[0071] (1) The automatic adjustment method provided by the present application acquires the filtration coefficient of the filtration device and the operation data of the reaction device, and feeds back to the control module, evaluates the filtration coefficient and the operation data first, and then guides the adjustment of the backflushing parameters of the backflushing device system, so that the filtration flux of the filtration device is kept within a certain range, avoiding the problems of invalid backflushing and untimely backflushing of the filter cloth, relieving the problem of filter cloth blockage caused by backflushing, thereby ensuring the mechanical strength of the filter cloth at the end of the operation of the reaction device, prolonging the operation cycle of the filtration device, and maintaining the normal production of the product;

[0072] (2) The automatic adjustment method provided by the present application realizes full-automatic control of the filtration backflushing device system, provides a scientific and effective basis for the filtration backflushing process, reduces the replacement frequency of the filter cloth of the filtration device, reduces the production cost, prolongs the operation time of the reaction device, reduces the number of system shutdowns, improves the yield of the single reactor device, overcomes the disadvantages of relying on the experience of operators for adjustment, and reduces the safety risk of the operators. BRIEF DESCRIPTION OF DRAWINGS

[0073] Figure 1 The present application provides a partial structure diagram of the filtration backflushing device system;

[0074] Among them, 1-reaction device, 2-filtration device, 3-product tank, 4-control module, 5-backwashing liquid tank, 6-gas storage tank, 7-third pressure sensor, 8-three-way valve, 9-liquid level sensor, 10-first valve, 11-second valve, 12-second pressure sensor, 13-first pressure sensor. DETAILED DESCRIPTION

[0075] In order to make the person skilled in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0076] It should be noted that the terms "first", "second", "candidate", "target" and the like in the specification and claims of the present application and the drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily limit to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0077] The present application provides a filter backwashing device system, a schematic diagram as shown in Figure 1 The filter backwashing device system comprises a control module 4, a backwashing device system and 26 filter devices 2.

[0078] The control module 4 is used for automatic control of the filter backwashing device system.

[0079] The backwashing device system comprises a gas storage tank 6 and a backwashing liquid tank 5 connected in sequence.

[0080] The gas storage tank 6 is provided with a first pressure sensor 13; the inlet pipeline of the gas storage tank 6 is provided with a second valve 11.

[0081] The pipeline connecting the backwashing liquid tank 5 and the gas storage tank 6 is provided with a first valve 10.

[0082] The backwashing liquid tank 5 is provided with a liquid level sensor 9.

[0083] The filter device 2 is a candle filter device; the candle filter device is provided with filter cloth; the filter precision of the filter cloth is 5-10 μm.

[0084] The filter device 2 is arranged in the interior of the reaction device 1; the filter device 2 is independently connected with the product tank 3 and the backwashing liquid tank 5 through the three-way valve 8.

[0085] The reaction device 1 is provided with a second pressure sensor 12; the pipeline connecting the reaction device 1 and the product tank 3 is provided with a third pressure sensor 7.

[0086] Embodiment 1

[0087] The embodiment provides an automatic adjustment method of a filter backflushing device system (a schematic diagram is shown in the figure), and the automatic adjustment method comprises the following steps: Figure 1 The automatic adjustment method comprises the following steps:

[0088] S110, acquiring a filtering coefficient of a filter device and operation data of a reaction device, and feeding back to a control module; the operation data comprises a feed load, an operation time and a pressure difference;

[0089] In step S110, the filtering coefficient of the filter device is calculated by using formula (I) :

[0090]

[0091] In formula (I), is the filtering coefficient, Q is an average backflushing flux (%), ΔP1 is a backflushing pressure difference (kPa), P1 is a backflushing pressure (kPa), and P2 is a pressure of the reaction device (kPa) ;

[0092] Specifically, the average backflushing flux of the filter device is 0-15%;

[0093] Specifically, the filtering coefficient of the filter device is 0-1;

[0094] In step S110, the pressure difference is calculated by using formula (II) :

[0095] ΔP2 = P3 - P2 (II)

[0096] In formula (II), P2 is the pressure of the reaction device (kPa), and P3 is the pressure of a production pipe of the reaction device (kPa) ;

[0097] Specifically, the pressure difference is 0-140 kPa;

[0098] S120, evaluating the filtering coefficient and the operation data to guide adjustment of backflushing parameters of the backflushing device system; the backflushing parameters comprise a single backflushing time, an interval time of adjacent backflushing and a backflushing pressure;

[0099] In step S120, the method of evaluation specifically comprises: taking the filtration coefficient of the filtering device as a first input variable, taking the feed load of the reaction device as a second input variable, taking the running time of the reaction device as a third input variable, and taking the pressure difference of the reaction device as a fourth input variable, determining the weight of each input variable, calculating a filtering performance attenuation value, triggering adjustment of the backflush parameter of the backflush device system according to the change of the filtering performance attenuation value, and outputting the optimal backflush parameter after iterative calculation;

[0100] Specifically, the weight of each input variable is determined by using an entropy weight method.

[0101] Specifically, the filtering performance attenuation value is calculated by using formula (III):

[0102]

[0103] In formula (III), H is the filtering performance attenuation value, B i is the input variable n, B1 represents the filtration coefficient of the filtering device, B2 represents the feed load of the reaction device, B3 represents the running time of the reaction device, and B4 represents the pressure difference of the reaction device, C i is the proportion of the ith input variable to the filtering performance attenuation value.

[0104] In formula (III), the value of C1 is 20-70%, the value of C2 is 0-80%, the value of C3 is 0-50%, and the value of C4 is 20-90%.

[0105] Specifically, the way of triggering adjustment of the backflush parameter of the backflush device system according to the change of the filtering performance attenuation value comprises the following cases:

[0106] When -1<ΔH≤0.05, the interval time of adjacent backflushes is triggered to be adjusted; or

[0107] When 0.05<ΔH≤0.5, the interval time and the backflush pressure of adjacent backflushes are triggered to be adjusted; or

[0108] When 0.5<ΔH≤1, the single backflush time, the interval time and the backflush pressure of adjacent backflushes are triggered to be adjusted.

[0109] Wherein, ΔH=H m+1 -H m , m≥1, and the update frequency of m and m+1 is ≤8h.

[0110] In step S120, the single backflush time is calculated by using formula (IV):

[0111]

[0112] In formula (IV), t is a single backflushing time (s), and F is a feed load of the reaction device (%);

[0113] Specifically, the single backflushing time is 1-10 s;

[0114] In step S120, the interval time of adjacent backflushing is calculated using formula (V):

[0115]

[0116] In formula (V), T is an interval time of adjacent backflushing (s), T0 is an interval time of initial backflushing (s), F is a feed load of the reaction device (%), and d is a running time of the reaction device;

[0117] Specifically, the interval time of adjacent backflushing is 50-2000 s;

[0118] In step S120, the backflushing pressure is calculated using formula (VI):

[0119]

[0120] In formula (VI), P4 is a backflushing pressure adjustment value (kPa);

[0121] Specifically, the backflushing pressure is 55-120 kPa.

[0122] The method provided in the embodiment, by obtaining the filtration coefficient of the filtration device and the running data of the reaction device, and feeding back to the control module, first evaluating the filtration coefficient and the running data, and then guiding to adjust the backflushing parameters of the backflushing device system, so that the filtration flux of the filtration device is kept within a certain range, avoiding the problems of invalid backflushing and untimely backflushing of the filter cloth, and relieving the problem of filter cloth blockage caused by backflushing, thereby protecting the mechanical strength of the filter cloth at the end of the reaction device running, prolonging the running cycle of the filtration device, and maintaining the normal production of the product.

[0123] Embodiment 2

[0124] In this embodiment, the separation of the catalyst and the crude BYD product in the production of BYD by acetylene aldehyde method is taken as the research object. The crude BYD liquid produced by acetylene aldehyde reaction, the unreacted formaldehyde solution, and the copper bismuth catalyst particles are filtered through the filter cloth on the surface of the candle filter device in the BYD reaction device. The filtrate is collected through the flow guide pipe inside the candle filter device, and a filter cake layer is gradually formed on the surface of the filter cloth. Then, 26 candle filter devices are backflushed in turn.

[0125] The embodiment provides an automatic adjustment method of a filtration backflushing device system (such as shown in the figure). Figure 1 The automatic adjustment method comprises the following steps:

[0126] S110, obtaining the filtration coefficient of the filtering device and the operation data of the reaction device and feeding back to the control module; the operation data includes feed load, operation time and pressure difference;

[0127] Wherein, Q=14%; P1=106kPa; P2=75kPa; P3=78kPa; F=50%; d=60 days;

[0128] According to the corresponding calculation formula in embodiment 1, the following is calculated in turn:

[0129] ΔP2=3kPa;

[0130] S120, when the feed load of the reaction device is slowly increased from 50% load to 100% load within 1 day, the filtration coefficient and the operation data are evaluated to guide the adjustment of the backflushing parameters of the backflushing device system; the backflushing parameters include single backflushing time, interval time of adjacent backflushing and backflushing pressure;

[0131] Based on F is the first input variable, F is the second input variable, d is the third input variable, and ΔP2 is the fourth input variable. The weights of the input variables are determined, the filtration performance decay value is calculated, the backflushing parameters of the backflushing device system are adjusted according to the change of the filtration performance decay value, and the optimal backflushing parameters are output after iterative calculation;

[0132] According to the corresponding calculation formula in embodiment 1, the following is calculated:

[0133] ΔH=0.75, triggering the adjustment of single backflushing time, interval time of adjacent backflushing and backflushing pressure;

[0134] The backflushing parameters obtained by iterative calculation according to the corresponding calculation formula in embodiment 1 are:

[0135] T=200s, t=6s, P4=100kPa;

[0136] After the above adjustment, the pressure difference of the reaction device is stabilized to 12kPa, the filtration coefficient of the filtering device is stabilized to 0.4, and the final reaction device continues to run for 120 days, and the filter cloth is not damaged and blocked.

[0137] Embodiment 3

[0138] The embodiment takes the separation of catalyst and crude BYD in the production of BYD by acetylene aldehyde method as the research object. The crude BYD liquid generated by acetylene aldehyde reaction, the unreacted formaldehyde solution and the copper bismuth catalyst particles are filtered through the filter cloth on the surface of the candle filter device in the BYD reaction device. The filtrate is collected through the flow guide pipe inside the candle filter device. A filter cake layer is gradually formed on the surface of the filter cloth. Then, 26 candle filter devices are sequentially back-flushed.

[0139] The embodiment provides an automatic adjustment method of a filter back-flushing device system (as shown in Figure 1 The automatic adjustment method comprises the following steps:

[0140] In S110, the filtering coefficient of the filter device and the operation data of the reaction device are obtained and fed back to the control module. The operation data includes the feed load, the operation time and the pressure difference.

[0141] Wherein, Q=9.1%; P1=96 kPa; P2=70 kPa; P3=100 kPa; F=100%; d=60 days.

[0142] According to the corresponding calculation formula in embodiment 1, the following is sequentially calculated:

[0143] ΔP2=30 kPa.

[0144] In S120, when the feed load of the reaction device is planned to be reduced from 100% load to 70% load, the filtering coefficient and the operation data are evaluated to guide the adjustment of the back-flushing parameters of the back-flushing device system. The back-flushing parameters include the single back-flushing time, the interval time of adjacent back-flushing and the back-flushing pressure.

[0145] Based on F is the first input variable, F is the second input variable, d is the third input variable, and ΔP2 is the fourth input variable. The weights of the input variables are determined, and the filtering performance decay value is calculated. The back-flushing parameters of the back-flushing device system are triggered according to the change of the filtering performance decay value. After iterative calculation, the optimal back-flushing parameters are output.

[0146] According to the corresponding calculation formula in embodiment 1, the following is calculated:

[0147] ΔH=0.64, triggering the adjustment of the single back-flushing time, the interval time of adjacent back-flushing and the back-flushing pressure.

[0148] According to the corresponding calculation formula in embodiment 1, the back-flushing parameters obtained by iterative calculation are as follows:

[0149] T=600 s, t=3 s, P4=70 kPa.

[0150] After the above adjustment, the pressure difference of the reaction device is stabilized to 25 kPa, the filtration coefficient of the filtering device is stabilized to 0.45, and the final reaction device continuously runs for 120 days without damage and blockage of the filter cloth.

[0151] Comparative Example 1

[0152] The present comparative example provides an adjustment method of a filtering backflushing device system, and other conditions are the same as those in Example 2 except that no control module is provided.

[0153] During the continuous production of the candle filter device, the operator manually adjusts the interval time of adjacent backflushing, and the time interval fluctuates in the range of 200-800 s. During the process of increasing the feed load of the reaction device from 50% to 100%, the pressure difference of the reaction device rises to 40 kPa in a short period of time due to the untimely adjustment of the backflushing parameters, and then continuously rises to 140 kPa. The reaction filtrate is difficult to produce, the on-site sight glass appears to be interrupted, and part of the candle filter device is cut out. The liquid level of the reaction device rises, and the reaction device runs for 65 days. Due to the high pressure difference and the difficulty in producing the filtrate, the reaction device is forced to run at a reduced load.

[0154] As can be seen from the comparison between Example 2 and Comparative Example 1, by setting the control module and adjusting the filtration coefficient of the filtering device, the pressure difference of the reaction device, the feed load and the running time of the reaction device through the cascade control of the control module to adjust the stability of the produced filtrate, the pressure difference of the reaction device is stabilized to 12 kPa, and the filtration coefficient of the filtering device is stabilized to 0.4. Compared with Comparative Example 1, the running period of the filter cloth is extended from 65 days to 120 days, and the total amount of formaldehyde consumed by the single-pot catalyst is increased by 9968 t.

[0155] Comparative Example 2

[0156] The present comparative example provides an adjustment method of a filtering backflushing device system, and other conditions are the same as those in Example 3 except that no control module is provided.

[0157] During the continuous production of the candle filter device, the operator manually adjusts the interval time of adjacent backflushing, and the time interval fluctuates in the range of 200-800 s. During the process of increasing the feed load of the reaction device from 50% to 100%, the pressure difference of the reaction device rises to 40 kPa in a short period of time due to the untimely adjustment of the backflushing parameters, and then continuously rises to 140 kPa. The reaction filtrate is difficult to produce, the on-site sight glass appears to be interrupted, and part of the candle filter device is cut out. The liquid level of the reaction device rises, and the reaction device runs for 65 days. Due to the high pressure difference and the difficulty in producing the filtrate, the reaction device is forced to run at a reduced load.

[0158] The applicant states that the present application is illustrated by the above-mentioned embodiments, but the present application is not limited to the above-mentioned detailed structural features, i.e. it does not mean that the present application must rely on the above-mentioned detailed structural features to be implemented. It should be understood by those skilled in the art that any improvement of the present application, equivalent replacement of the components selected by the present application, addition of auxiliary components, selection of specific modes, etc. fall within the protection scope and disclosure scope of the present application.

Claims

1. An automatic adjustment method of a filter backwash device system, characterized by, The filter backflush device system comprises a control module, a backflush device system and at least one filter device; The automatic adjustment method comprises: Obtaining the filter coefficient of the filter device and the operation data of the reaction device and feeding back to the control module; the operation data comprises feed load, operation time and pressure difference; Evaluating the filter coefficient and the operation data to guide the adjustment of the backflush parameters of the backflush device system; the backflush parameters comprise single backflush time, interval time of adjacent backflush and backflush pressure.

2. The method of automatically adjusting of claim 1, wherein, The control module is used for the automatic control of the filter backflush device system; Preferably, the backflush device system comprises a gas storage tank and a backwash liquid tank connected in sequence; Preferably, a first pressure sensor is arranged on the gas storage tank; Preferably, a first valve is arranged on the pipeline connecting the backwash liquid tank and the gas storage tank; Preferably, a liquid level sensor is arranged on the backwash liquid tank; Preferably, the filter device comprises a candle filter device; Preferably, the filter device is arranged in the interior of the reaction device; Preferably, the filter device is independently connected with a product tank and a backwash liquid tank respectively; Preferably, a second pressure sensor is arranged on the reaction device; Preferably, a third pressure sensor is arranged on the pipeline connecting the reaction device and the product tank.

3. The automatic adjustment method according to claim 1 or 2, characterized in that, The filter coefficient is calculated by using formula (I): wherein wherein F is the filtration factor, Q is the average backflush flux of the filtration device (%), ΔΡ1is the backflush pressure difference (kPa), Ρ1is the backflush pressure (kPa), and P2is the pressure of the reaction device (kPa). Preferably, the average backflush flux of the filter device is 0-15%; Preferably, the filter coefficient of the filter device is 0-1.

4. The method of automatic adjustment according to any of claims 1-3, characterized in that, The pressure difference is calculated by using formula (II): ΔP2=P3-P2 (II) Wherein, P2 is the pressure (kPa) of the reaction device, and P3 is the pressure (kPa) of the production pipe of the reaction device; Preferably, the pressure difference is 0-140 kPa.

5. The method of automatic adjustment according to any of claims 1-4, characterized in that, The evaluation method specifically comprises: Based on the filter coefficient of the filter device as the first input variable, the feed load of the reaction device as the second input variable, the operation time of the reaction device as the third input variable and the pressure difference of the reaction device as the fourth input variable, the weights of the input variables are determined, the filter performance attenuation value is calculated, the backflush parameters of the backflush device system are adjusted according to the change of the filter performance attenuation value, and the optimal backflush parameters are output after iterative calculation.

6. The method of automatically adjusting of claim 5, wherein, The weights of the input variables are determined by using the entropy weight method; Preferably, the filter performance attenuation value is calculated by using formula (III): wherein H is a filter performance degradation value, B i is an input variable n, and B1 represents a filter coefficient of the filter device, B2 represents a feed load of the reaction device, B3 represents a running time of the reaction device, B4 represents a pressure difference of the reaction device, C i is a proportion of the i-th input variable to the filter performance degradation value; Preferably, the value of C1 is 20-70%; Preferably, the value of C2 is 0-80%; Preferably, the value of C3 is 0-50%; Preferably, the value of C4 is 20-90%.

7. The automatic adjustment method according to claim 5 or 6, characterized in that, The way of adjusting the backflush parameters of the backflush device system according to the change of the filter performance attenuation value comprises the following cases: When -1<ΔH≤0.05, the interval time of adjacent backflush is triggered to be adjusted; Or When 0.05<ΔH≤0.5, the interval time of adjacent backflush and the backflush pressure are triggered to be adjusted; or When 0.5<ΔH≤1, the single backflush time, the interval time of adjacent backflush and the backflush pressure are triggered to be adjusted; where ΔH = H m+1 -H m , m≥1, and the update frequency of m and m+1 is ≤8h.

8. The method of automatically adjusting according to any of claims 1-7, wherein, The single backflush time is calculated by using formula (IV): Wherein, t is the single backflush time (s), F is the feed load of the reaction device (%); Preferably, the single backflush time is 1-10 s.

9. The method of automatic adjustment according to any of claims 1-8, characterized in that, The interval time of the adjacent backflush is calculated by using formula (V): Wherein, T is the interval time of the adjacent backflush (s), T0 is the interval time of the initial backflush (s), F is the feed load of the reaction device (%), d is the operation time of the reaction device; Preferably, the interval time of the adjacent backflush is 50-2000 s.

10. The method of automatic adjustment according to any of claims 1-9, characterized in that, The backflush pressure is calculated by using formula (VI): Wherein, P4 is the backflush pressure adjustment value (kPa); Preferably, the backflush pressure is 55-120 kPa.

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