[0029] The technical solution of the present invention will be further described below in conjunction with the drawings and embodiments.
[0030] The simulation method for detecting the clogging process of the industrial fluid pipeline filter screen of the present invention includes the following steps:
[0031] A. Punch holes at the front and rear ends of the filter screen of the pipeline to take pressure, and obtain the initial pressure difference through a differential pressure transmitter and detect the pressure difference in real time;
[0032] B. Real-time detection of pipeline flow using flow measurement;
[0033] C. Establish a simulation computing processor to receive the measured pressure difference and measured flow rate, and calculate the simulated real-time value of the clogging degree of the simulated filter;
[0034] D. Perform corresponding display or/and alarm according to the simulated real-time value.
[0035] Wherein, the step C specifically includes the following steps:
[0036] C1. According to the initial pressure difference, calculate the correction coefficient K1 of the measured differential pressure value to the output signal range;
[0037] C2. According to the rated flow of the pipeline during normal production, calculate the correction coefficient K2 for the output signal when the measured flow is lower than the rated flow;
[0038] C3. According to K1, K2, measured pressure difference and measured flow rate, the simulated real-time value is calculated.
[0039] The calculation formula used in steps C1 ~ C3 is as follows:
[0040] K 1 = Δ P max / ( Δ P max - ΔPo ) ①
[0041] K 2 = ΔPo / Qs ②
[0042] Yx = K 1 ( 1 - K 2 X Qx / ΔPx ) X 100 % ③
[0043] Where
[0044] Yx is the simulated real-time value of the clogging degree of the simulated filter; Qs is the rated flow during normal production; Qx is the measured flow; ΔPo is the measured and recorded value when the pipe flow reaches the rated flow of normal production after the pipe filter is newly installed or replaced The initial differential pressure value at both ends of the filter screen; ΔPmax is the maximum allowable differential pressure value at both ends of the filter screen when the pipeline is normally produced at the rated flow; ΔPx is the measured differential pressure at both ends of the filter screen; K1 is the measured differential pressure value to the output signal The correction coefficient of the range; K2 is the correction coefficient of the output signal when the measured flow is lower than the rated flow.
[0045] In step D, perform one or more of the following display modes according to the simulated real-time value:
[0046] D1. Carry out 0~100% simulation digital display;
[0047] D2. Carry out simulation LED light beam display;
[0048] D3. The remaining time is displayed.
[0049] In step D, when the simulated real-time value is greater than the upper limit alarm value, an alarm signal is output.
[0050] In step D, the simulation operation processor compares the current simulated real-time value Yx with the simulated real-time value Yx-1 of the previous processing cycle according to the signal processing cycle during the continuous data collection and calculation process, when When Yx≤Yx-1, the output display remains unchanged.
[0051] See figure 1 As shown, specific examples are given below according to the technical solution of the present invention:
[0052] 1. Known conditions
[0053] The fluid medium is a mixed gas containing blast furnace gas, the pipe diameter is DN500, the filter is installed horizontally, and the rated flow Qs is 10000m 3 /h (In some periods of time due to production reasons, the actual flow will be less than the rated flow), the pipeline pressure is 20kpa (gauge pressure, the same below), the process design allows the maximum differential pressure ΔPmax at both ends of the filter to be 2kpa (or under the rated flow, When the differential pressure at both ends of the filter reaches 2kpa, the filter is considered blocked). The orifice plate flow metering device has been installed on the mixed gas pipeline, with a range of 0-12000m 3 /h, the corresponding output signal is 4-20mA.
[0054] 2. Implementation steps
[0055] 1) Open a hole to take pressure on the 0.5D main pipeline before and after the filter screen (the pressure pipe is constructed according to the pressure taking method of the throttling device, D is the inner diameter of the pipe), and the differential pressure transmitter is connected to the differential pressure transmitter. The range is set to 0-2kpa, and the corresponding output signal is 4-20mA. When the new filter is replaced and the rated flow is reached, the initial differential pressure is recorded as ΔPo=0.05kpa.
[0056] According to the calculation method and logical relationship of formula ③, a simulation calculation processor is made. The simulation calculation processor has a two-way analog input module (AI module), which corresponds to the current signal output by the two-terminal differential pressure transmitter of the filter and the external flow. The current signal is converted into a digital signal. The simulation computing processor panel can set three data of K1, K2 and alarm point. The main output of the simulation computing processor is a four-digit 0-100% digital display value and twenty segments (each segment increases by 5%) of the LED light beam analog value. Auxiliary output: When an alarm occurs, a passive relay normally open contact is closed, and the remaining time is displayed.
[0057] According to the initial differential pressure value ΔPo, the known maximum differential pressure ΔPmax and the rated flow meter Qs recorded on site, the K1 and K2 values can be calculated according to formulas ① and ②, and set in the simulation processor panel.
[0058] The measured flow signal and the output signal of the differential pressure transmitter are connected to the designed simulation calculation processor.
[0059] According to the production requirements, when the filter screen's clogging degree reaches 95%, an alarm signal that the normally open contact of the passive relay is closed is required, and an upper limit alarm value of Yh=0.95 is input at the panel alarm set point. When the measurement signal Yx rises to Yh When the passive relay normally open contact is closed, an alarm signal is sent out.
[0060] During the use of the filter, the clogging process is a slow increasing process. In order to prevent system interference, the output display value (digital value and LED light beam analog value) can only increase or remain unchanged. The principle is: in the process of continuous data acquisition and calculation by the simulation computing processor, according to the signal processing cycle, the current calculation result value Yx is compared with the calculation result value Yx-1 of the previous processing cycle, when Yx≤Yx-1 When the output display value (digital quantity and LED light bar) remains unchanged.
[0061] Due to the long time of the filter blockage process, the system outputs a "remaining time" for maintenance and inspection personnel to refer to. The calculation formula of the "remaining time" is T=(τ n -τ n-1 )*(20-n)-(τx-τ n ), τx is the real-time accumulated time, n=1~19 (the number of records of τ).
[0062] After completing the setting of the three parameters of the panel and the connection of the two signals of flow and differential pressure, the blocking process of the filter can be continuously monitored. After replacing the filter, the simulation computing processor needs to be initialized, and the system output display value is cleared.
[0063] To sum up, the simulation detection method of the present invention continuously measures the differential pressure at the two ends of the pipe filter and the pipe flow rate, and is calculated by the above formula, linearly outputting a digital value of 0-100% and 20 segments (each segment increases by 5% ) The simulated value of the LED light beam reflects the degree of clogging of the filter in real time. Its technical characteristics are: after the pipe filter is newly installed (or replaced), when the pipe flow reaches the rated flow of normal production (process design), measure and record the initial value of the differential pressure ΔPo at the two ends of the filter, and the initial value of the differential pressure As one of the original parameters to calculate the correlation coefficient in the formula. Set the maximum differential pressure value ΔPmax allowed at the two ends of the filter screen to the value of the filter screen when the pipeline is at the rated flow rate of normal production, and use the maximum differential pressure value as one of the original parameters for calculating the correlation coefficient in the formula . In order to improve the accuracy of measurement and prevent system interference due to abnormal production conditions, according to the slowly increasing characteristics of the filter blockage process, the measurement value has the function of output retention, that is, the output display value (digital value and LED light column analog value) Can only increase or remain unchanged. Therefore, the clogging degree of the filter can be monitored throughout the entire process, thereby improving the planning of equipment maintenance and the effectiveness of equipment maintenance.
[0064] Those of ordinary skill in the technical field should realize that the above embodiments are only used to illustrate the present invention, but not to limit the present invention. As long as they are within the essential spirit of the present invention, the Changes and modifications will fall within the scope of the claims of the present invention.
