烛式过滤器过滤原理 Filtering Principle

烛式过滤器也称为滤饼层过滤器，由立式容器和垂直安装的过滤单元组成。其过滤单元是以开孔的花瓣式的滤芯和滤布组成。实际的过滤介质是包裹在滤芯表面的滤布和滤饼层，滤布用专用的卡箍紧固在滤芯的表面使其密封。它的过滤过程是完全密闭的，无泄漏，没有任何的环境污染。可以实现一次性全过程自动化过滤，滤饼洗涤、风干，同时采用气体反吹排渣等工艺。整套过程速度快，无污染，可获得最大工作效率。

Candle filter is also called filter cake layer filter, it is composed of the vertical vessel and vertically installed filter units. The filter units consist of poriferous petaloid filter cartridge and filter cloth. The real filter medium are the filter cloth and filter cake layers that covering the filter cartridge. Filter cloth is fixed on the surface of filter cartridge to make it fully sealed by using special clamps. The entire filter process is totally sealed without any spillage or environment pollution. It can realize automatic filtration, feeding washing & air drying, and air back blowing to discharge residuals at one time. The filter process is in high speed and zero pollution, it brings largest economic benefit.

主要结构及工作原理 Main Structure & Working Principle

烛式过滤器是一个全密闭的过滤系统，主要部件有物料罐、储气罐、过滤泵、烛式过滤器、管道、阀门、PLC电器控制等组成。

过游时用泵将需过滤纳样送入过滤器内，当液体经过滤布时，会在滤布表面逐步集聚液体中的固体物质，当这些固体物质达到一定算度时，就形成了读讲。由于消瘦增加之间的空意很小，阻留了滚体中颠粒杂质的遗遗遗，这样就使滤液变清，在满饼温未形成前，排出的“清液”再回到原物料罐作循环过滤，直至溶饼层形成（能达到过滤要求），过滤器提供一信号给PLC控制清液不再循环，清液锂过过滤阀送至下道工序使用，进行正常过滤。

正常过滤一段时间后，当多孔烛芯上满饼层达到-定厚度时，满液通过滤饼的速率降低，过滤波率变差，过滤得压力升高（0.5MPc以上）这时压差开关（或者压力传感器）提供-信号给PLC停止过滤泵泵泵、关闭进料阀，打开正吹阀，然后捧净过滤器内的总液，当过滤器内液体低于满芯时打开排液调随液通过排液阀撑，这时过清器内压力迅速下降PLC接收到低压信号，关闭正欢阀，打开反攻倒（压缩空气、复气或饱和蒸汽）进行反取，使满饼脱落，反吹一定时间后（30秒），停止反吹，打开过湍器排渣口进行排渣，排灌结束后关闭排渣口，完成一个过湍周期，回到过游前初始状态，准备进行下一轮过渴

Candle filter is a fully closed filter system. Its main parts are the material tank, air storage tank, feeding pump, candle filter, pipes, valves, PLC electric control system.

While filtering, filter material will be sent into the filtering housing by feed pump first; when it passes through filter cloth, solid particles will be stopped on the filter cloth. And as the solid particles growing, they will become filter cakes. The holes hpetween solid particles are very small, so they can kkeep more solid particles, thus get clear liquid. Before solid particles becoming cakes, the filtration will be sent back to filter material tank and resend to vessel again. When filter cakes are formed (and reaches required requirement), PLC will send a signalto stop the circulation, and the clear liquid will pass the filter valve and go to next process to start the normal filtering process.

After certain time normal filtering, the cake thickness is increasing to high level, the filtering speed is slow down, filtering efficiency is decreased, and the filter pressure is >0.5MPa, then the pressure sensor will send a signal to PLC to stop feed pump, close feed valve and open forward blowing valvee to remove the filtrate in vessel. When the liquid level in vessel is lower than filter cartridge, PLC will open drain valve to discharge filtrate, the pressuure will drop swiftly. When PLC received low pressure signal, it will close forward blowing valve and pen back blowing valve (compressed air, nitrogen or steam) to back blow until cakes fall down. Stop bloowing after 30 seconds, and open cake dischargingoutlet to discharge cakes. When cakes are discharged, close the cake discharging outlet to finish the filtering cycle. The candle filter will be ready for next cycle.