RU2743560C1 - Method for automated maintenance of trouble-free operation of filter-dust arrester - Google Patents

Abstract

FIELD: automated control systems.

SUBSTANCE: invention relates to systems for automated control of filter-dust collector operation to ensure trouble-free operation modes and can be used for automation of aspiration systems with dust collectors filters in food, metallurgy, pharmaceutical and other industries. Method of controlling regeneration of filters includes feeding dusty gases into a bag filter, regenerating hose filters by blowing with compressed air and after a certain period of time measuring gas pressure before and after the filter module. Filtering process is stopped when condition ΔP_n+1≤ΔP_n, where ΔP_n, ΔP_n+1 is total pressure drop on filter, measured at current moment in time and total pressure drop on filter, measured at previous time, Pa; n is measurement number of total pressure difference as the filtration process is carried out. Further, regeneration of filters is performed until condition ΔP_n/ΔP_n-1≤0.5, where ΔP_n, ΔP_n-1 is total pressure difference on the filter after regeneration and total pressure difference on the filter before regeneration, Pa. Otherwise, filtering layer is replaced so that condition ΔP_n/ΔP_n-1≥0.2, where ΔP_n, ΔP_n-1 is total pressure difference on filter after and before layer change, Pa; after which filtration is resumed.

EFFECT: method increases reliability and efficiency of operation of an aspiration system equipped with a filter-dust arrester.

1 cl, 1 dwg

Description

The invention relates to systems for automated control of the operation of dust filters for maintaining trouble-free operating modes. The invention can be used to automate the operation of aspiration systems with dust filters in the food, woodworking, metallurgical, pharmaceutical, chemical, textile industries and other industries.

The closest in technical essence and the achieved effect is a method for controlling the regeneration of baghouse filters (Lisienko V.G., Sokolov A.G., Zotov SA Method for controlling the regeneration of baghouse dust filters: Pat. No. 2337747 of the Russian Federation. 2008. Bull. 31.8c.)., Including the supply of dusty gases to the bag filter, regeneration of bag filters by blowing with compressed air and after a certain period of time, measuring the gas pressure before and after the bag filter module. The time interval between bag filter regenerations is set depending on the pressure drop before and after the bag filter module, while setting the maximum and minimum time intervals between pulses for filter regeneration, as well as the minimum and maximum pressure drop across the bag filter module, and in the case of a minimum and the maximum preset pressure drop values, respectively, the maximum and minimum preset time intervals between regeneration pulses are set, and in the case of an intermediate pressure drop between its minimum and maximum preset values, the time interval between regeneration pulses is determined according to the formula given in the patent for invention. EFFECT: automatic regulation of the time interval between filter regeneration and the action of compressed air jets depending on the pressure drop across the bag filter, increasing the level of gas purification, reducing the compressed air consumption for regeneration.

The disadvantage of this method is that it is designed only for the normal functioning of the filter and the absence of emergencies and complete clogging of the filter material when regeneration is no longer possible. Therefore, this method has low reliability.

The technical objective of the invention is to improve the reliability and efficiency of filters.

The technical problem of the invention is achieved by the fact that when implementing the method for controlling the regeneration of filters, including supplying dusty gases to the bag filter, regenerating the bag filters by blowing with compressed air and after a certain period of time, measuring the gas pressure before and after the filter module, it is new that filtration process is stopped when the condition ΔP _{n + 1} ≤ΔP _n, where ΔP _n, ΔP _{n + 1} - the total pressure drop across the filter measured at the current time and the total pressure drop across the filter measured in the previous time, Pa; n is the number of measurement of the total pressure drop during the filtration process, after which the filters are regenerated until the condition ΔP _n / ΔP _n-1 ≤0.5 is satisfied, where ΔP _n , ΔP _n-1 is the total pressure drop across filter after regeneration and the total pressure drop across the filter before regeneration, respectively, Pa; otherwise, the filter layer (material) is replaced in such a way that the condition ΔP _n / ΔP _n-1 ≥0.2 is met, where ΔP _n , ΔP _n-1 is the total pressure drop across the filter after and before the layer change, Pa; after which filtration resumes.

The technical result consists in increasing the reliability and efficiency of the filter; in the possibility of automating the process for more effective control.

FIG. 1 shows a diagram of an algorithm for implementing a method for automated maintenance of trouble-free operation of a dust-collecting filter.

The method is implemented as follows. When controlling the operation of the aspiration system, the occurrence of emergency situations in the operation of the system is of particular importance. Normal filter operation is associated with the gradual clogging of the filter baffle, which leads to an increase in the total pressure drop across the AP filter. Thus, during normal operation, each subsequent value of the total differential pressure is greater than or equal to the previous one.

If the condition is met

ΔP _{n + 1} ≤ΔP _n ,

where n is the number of measurements of the total pressure drop across the filter, we can talk about an emergency process flow. This condition is checked for 50 cycles, each of which can last from 10 to 30 seconds. This time is given to the filter to stabilize the mode. If, after the implementation of 50 cycles, the condition is met, the filter should be regenerated, since it is either clogged or initially has inappropriate input characteristics for this dust and gas flow.

The regeneration process is in progress. The condition for effective regeneration is the following

ΔP _n / ΔP _n-1 ≤0.5,

where ΔP _n , ΔP _n-1 are the total pressure drop across the filter after regeneration and the total pressure drop across the filter before regeneration, respectively, Pa.

Control regenerations are allowed, after which the bed is considered unsuitable for further filtration, while the initial pressure drop across the regenerated bed should be no more than 50% of the final pressure drop before regeneration. The total number of regenerations is m (see Fig.).

Then there is a layer change, which is also not always effective. Condition for effective layer change

ΔP _n / ΔP _n-1 ≤0.2,

where ΔP _n , ΔP _n-1 is the total pressure drop across the filter after and before changing the layer, Pa; after which filtration resumes.

It is considered that the bed can be used for filtration if the total pressure drop after the change does not exceed 20% of the final pressure drop before the change.

The number of layer changes - k. If this condition is not met during three shifts (k = 3), we can say that all possible malfunctions that could be corrected automatically have been checked, and then we are talking about the emergency operation of the filter, which is indicated by the corresponding signal from the control unit operator.

The proposed method for the automated maintenance of trouble-free operation of the filter-dust collector makes it possible to increase the reliability and efficiency of the operation of the aspiration system equipped with the filter-dust collector.

Claims (1)

A method for automated maintenance of trouble-free operation of a dust-collecting filter, including supplying dusty gases to the filter, regenerating filters by blowing with compressed air and after a certain period of time, measuring gas pressure before and after the filter module, characterized in that the filtering process stops when the condition ΔР _{n + 1} ≤ ΔP _n , where _{ΔР n} , ΔP _{n + 1} is the total pressure drop across the filter, measured at the current time and the total pressure drop across the filter, measured at the previous time, Pa; n is the number of measurement of the total pressure drop as the filtration process proceeds, after which the filters are regenerated until the condition ΔP _n / ΔP _n-1 ≤0.5 is satisfied, where ΔP _n , _{ΔР n-1} is the total pressure drop across filter after regeneration and the total pressure drop across the filter before regeneration, respectively, Pa; otherwise, the filter layer (material) is replaced in such a way that the condition _{ΔР n} / ΔP _n-1 ≥0.2 is met, where ΔP _n , ΔP _n-1 is the total pressure drop across the filter after and before the layer change, Pa; after which filtration resumes.

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