Pneumatic Scraper Type Self-cleaning filter

Pneumatic Scraper Type Self-cleaning Filter by mechanical scraping ways to automatically remove the particulate impurities of filter element surface , and it is a continuous online single-filter filtration, no consumable, no frequent manual cleaning job, be suitable for a filtration of general or high viscosity liquid.

   It is easy to be blocked when the traditional manual filter is used for the filtration of viscous materials and soft impurities, the customers are forced to select a large filter or frequently backwashing, the cost of investment is large, heavy workload, and a serious waste of materials. Pneumatic scraper type self-cleaning filter can easily solve such these problems, and, it can always keep the filter element clean, a high impurity for exhausted slag liquid, the waste material  is small.

      Pneumatic scraper self-cleaning filters are replacing traditional manual filters in many fields because of their significant technological advantages and low life-cycle costs. Such as vibrating screens, bag filters, basket filters, and some backwash self-cleaning filters, etc. 

Operating principle

Process of Filtration

 

Liquid inflow from the inlet, with a disc-shaped scraper blade close to the inner surface of the filter element, stopping at the top filter element, the liquid medium outflow from the inner surface to the outside surface of the filter element, the impurities are trapped in the inner surface of filter element, the liquid medium outflow from the outlet. As time goes by, the impurity increases gradually, the pressure difference rises, the control system send a demand by the differential pressure transducer (or Timer) to the pneumatic actuator which will drive the scraper to finish cleaning. 

Process of Self-Cleaning

Pneumatic actuator drive the scraper to clean the filter element backwards and forwards from up and down, when the scraper move down, impurity is pushed the bottom of the filter by the scraper, a large proportion of the impurities is collected in collection chamber. When the scraper moves upward, the impurity is scratched and pushed to the top of the filter element. The impurity is washed away by the flowing liquid. Need the same action multiple times to finish a whole cleaning, then, Cleaning process is finished.  And then, The system restore its original status to finish new process, the flow is not interrupted.

 

Blow-down Process

After some cleaning period, a certain amount of impurities is collected, the control equipment open the sewage valve regularly , accumulation of impurities to a certain amount of equipment to open the sewage valve on a regular basis, discharge the high concentrations of impurities ,if necessary, can be recycled.

 

Configuration instructions

A design of the long slit-type mesh screen, the gap of mesh screen is a V-shape, not easy to be blocked by the impurities, maintain a stable flow in long term. The width of gap on the internal surface of mesh screen, is just the filtration precision. uniform gap, , accuracy range of 50-1500 microns. The Scraper is scraping along with the gap direction, be suitable for conventional filtration requirements. Smooth inner surface, accurate roundness, good scraping effect. solid structure, durable service. Mesh screen material is 316L, excellent corrosion resistance, Some troublesome impurities can also be filtered, such as: sludge type impurities, soft caking impurities