Standard Formulation For The Determination And Evaluation Of Seam Performance Of Industrial Dust Filter Bags

Bag house is the mainstream technology for industrial dust and flue gas treatment.The core element of bag house is filter bag.The filter bag is made of filter material by sewing or hot-melting process,and the dust in the flue gas is filtered through the curved pores of the filter material to achieve the effect of dust removal.The structural performance of the filter material and the fiber material are directly related to the filtering effect and service life of the filter bag.There are many national and industry standards to measure and evaluate its performance.The seam of the filter bag has an important influence on the filtering effect and service life of the filter bag,but there is currently no relevant standard to measure and evaluate its performance.The development of the measurement and evaluation standards for the seam performance of the filter bag is conducive to improving the technical requirements of the filter bag industry and avoids the performance of the filter bag seam not meeting the actual working conditions,resulting in a substantial decline in the filter performance of the filter bag,which will not only damage the enterprise economic benefits,and it is contrary to the green and sustainable environmental protection requirements.This topic focuses on the determination and evaluation standards of the seam performance of filter bags.The main research contents and conclusions are as follows:（1）Investigation and analysis of the causes of damage and failure of filter bagsThe investigation of the damage form and cause of the filter bag found that under the actual working conditions,the filter bag will be scoured by the pulsed dust-cleaning airflow and dust-laden flue gas,and friction may occur between the filter bag,the filter bag and the box.High temperature damage and acid-base corrosion also occur from time to time,so the proposed filter bag seam measurement indicators are appearance quality,fatigue resistance,seam strength,dust filter performance,temperature resistance characteristics and corrosion resistance.（2）Research on the evaluation method of joint fatigue resistance and joint strength of filter bagThe fatigue resistance of the filter bag was evaluated by the change of the air permeability of the seam of the filter bag after repeated topping.The seam of the filter bag is repeatedly punched with a spherical ejector rod.The constant load is set to 50 N,100N,and 150 N,and the number of cycles is set to 10,20,and 50 times.The air permeability test items include basic air permeability,seam air permeability,Comprehensive air permeability.The results found that the fatigue resistance of the filter bag seam can be evaluated by using a constant load value of 100 N and 50 cycles of repeated topping before and after the change rate of the air permeability of the filter bag seam is less than the comprehensive air permeability change rate of the filter bag.By testing the seam strength of sewing and hot-melt filter bags provided by many companies,and consulting other relevant standards,the evaluation requirements for the seam strength of the filter bag are: the seam strength of the sewing filter bag should not be less than the weft direction of the filter material.The breaking strength,the joint strength of the hot melt filter bag should not be less than 800 N.（3）Establishment of other performance indicators of filter material jointsComprehensively refer to GB/T 6719-2009 "Technical Requirements for Bag Filters",T/CAEPI33-2021 "Technical Requirements for Bag Filter Bags" and T/CNITA 05105-2021 "Filter Bag Technology for Ultra-Low Emissions of Industrial Smoke and Dust" Requirements" and other standards,the quality evaluation requirements for the appearance of the seam of the filter bag are: the surface of the seam should be clean,no defects,no holes,no oil stains,there should be no floating lines,no sagging at the sutures,and the sutures should be glued.It should be filled with fastness,no cracks,no voids at the hot-melt joints,and no film falling off on the surface of the film-coated filter material;the evaluation requirements for dust filter performance are: resistance ≤ 300 Pa,dynamic dust removal efficiency ≥99.99%,PM 2.5 capture efficiency ≥ 99.5%;temperature resistance and corrosion resistance,it is stipulated that the material of the filter bag sewing thread should be consistent with the fiber material of the filter material used in the filter bag.When selecting sewing threads of other fiber materials,the basic performance of the sewing thread must be verified by experiments The index is not lower than the sewing thread of the same filter material.（4）Drafting of the first draft of the standardFor the seam of the filter bag,according to the determined performance indicators,test methods and evaluation requirements,the first draft of the industry standard "Determination and Evaluation of Seam Performance of Industrial Dust Filter Bags" was written.