| This paper firstly summarizes and analyzes the status quo of china industrial pollution and increasingly stringent environmental protection standard requirements, then the paper give a brief introduction to the development and application status of the bag filter, after compared the performance of several high temperature fiber, we emphasis on PTFE fiber in high temperature dust application prospects. PTFE fiber can be provided at 260℃ long-term use, the short can be resistant to a high temperature of 300℃, the limiting oxygen index(LOI)of 95%; In addition to molten alkali metal, fluorinated medium and higher than 300℃ sodium hydroxide outside, PTFE almost without any chemical reagent of the corrosion. Therefore, PTFE is very suitable for high-temperature filter material, it can filter high temperature flue gas in harsh environments. It must have two major functions when in the application of filter, namely in the long period of work remain maintain its strength and occurs only rarely the creep amount. Due to its long time by the high velocity and pulse force, meanwhile the PTFE have a bad creep performance, so it is necessary to study its creep properties, and determines whether the amount of creep under the long term effects the stability of work.The sample for experiment is PTFE needle-punched nonwoven filter material, they have two kinds of specifications, one of them is made of PTFE short fiber with PTFE long fiber woven base cloth, the other is made of 50%PPS+50%PTFE with long fiber woven base cloth. The paper first study two specifications filter material basic properties and high temperature mechanical properties, namely test the breaking strength and breaking elongation in the room temperature(20℃),150℃,180℃,210℃,240℃. Secondly research the creep behavior of sample in normal temperature 20℃ with separately 20%,40%,60%,80% fracture load level, experimental data processing method, and analysis acupuncture reinforced the creep mechanism of filter material. For PTFE needled filter material is mainly used in high temperature dust filter, the experiment also innovative test creep condition in the 180℃ and above temperature at different load level.Creep refers to the textile material under constant tension function, its deformation changes process with time change. Using the test method, the sample was cropped to a certain size, having one end fixed and the other end aggravated, and then measured the deformation rate of the material in different time under different weighting conditions, at last further derived the creep properties required in the actual work environment indicators.Data processing was divided into three parts:first,analyzing testing data by empirical formula, seeking creep mechanism, and judging firstly whether the creep value in long-term constant load action affects engineering stability or not. Second, Establishing models which can simulate creep characteristic of needle-punched filter material:model of six elements paralleling connection Third, by origin software, forecasting long-term creep capability of with valid creep model, and judging whether the creep characteristic under different loads have influence on the engineering stability and durability or not. The innovation spots in this paper:Conducting an experiment about composite firstly, and separately studying the situation of 20%o40%o60%o80% limited load level action; Models of creep behavior for the sample were established. The PTFE needle-punched non-woven material with high temperature critical temperature and safe work temperature was analyzed qualitatively in this paper. |
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