SCIF / SCEF Automatic Self Cleaning Filters

Fully automatic self-cleaning screen filters provide an economical means of removing suspended solids down to 40 microns from liquid streams. Filters equipped with the efficient suction scanning principle allow the filter cake to be removed completely from the screen surface within seconds without physically touching the cake or screen.
 

Design

The design of Automatic Self Cleaning Filters is mainly to remove grit, grime, algae, dirt, and rust particles from liquid stream. A range of applications can be handled in the Pharmaceutical, Biotech, Chemical, F&B, Wines and Breweries, Dyes and Dye Intermediates, etc.

Features and Benefits

• Available in SS Wire Mesh or Wedge Wire  
• Pressure ratings up to 15-20 Kg/cm2
• End Connections: 1” to 2” NPT
• Flanged End : ¾” to 3”, 6” and 8” NB ASA #150, #300, #600, #900
• Material of Construction: CS, SS 304, SS 316, SS 316 L, SS 321, Monel, Inconel, Cu-Ni etc.
• Generally designed as per ASME
• Low-pressure drop
• Range of temperature from minus up to 200 ºC operating
• Inlet outlet connections - Threaded, flanged
• Easy to open - Rothman clamps or Davit arm assembly for top dome opening (Hydraulic closing and opening available as an option)
• Epoxy finish on carbon vessels

Operation

The liquid to be filtered enters the housing above the Wedge screen, flows down into the housing,

SS Mesh or Wedge wire drums are configured with either a mechanical cleaning system or an auto-flushing arrangement for intake dirty fluid stream.

In case of a mechanical cleaning system motor or a pneumatic cylinder moves a mechanical scraper over a wedge wire filter element in an axial direction.

This is actuated by means of a pressure differential valve and the difficult backwash comprising of mainly fibrous materials, granules, or organic waste, are pushed to the outlet and drained away through the flush valve.

The backwash flushing is regulated by a programmable timer and if necessary parallel linked with a differential pressure control. The cylinder can be designed to make several movements axially or radially based on the design type and application. Backwash flushing cycles range from 5-10 secs and are enough to clean the complete filter element. And in case the flow has to be continuous then an intermittent buffer tank should be provided to take care of the disruption of flow for 5-10 secs.

The normal material of construction is SS 304 or 316 for the wedge screens and depending on the liquid chemical composition the main body can be made from MS or SS

Technical Specifications

The size of the Filter can be designed as per the flow rate considerations. The degree of automation desired is solely up to the clients’ discretion.

Automatic Self Cleaning filters effectively remove dirt, pipe scale, and other contaminants from process liquids such as water, chemical and petroleum products. Quality construction and design ensure protection for all downstream equipment.

A wide range of pressure vessels and allied equipments are manufactured to high engineering standards. Vessels are constructed from polypropylene, Mild steel, Stainless steel (304 or 316) or other specialist metals.

Equipment Connections can be NPT, BSP and ASA screwed or flanged in different configurations to suit various requirements. All filter vessels are supplied complete with a stainless steel retainer basket and standard rubber O-ring.

Applications and Uses

Automatic Self Cleaning Filters find use in removing sand, silt and algae from raw water rivers and canals. These give effective pretreatment before membrane filtration systems for process water supply, Pretreatment for reverse osmosis and desalination systems, Industrial wastewater treatment plants use these filters to prepare secondary effluent for reuse in cooling, irrigation.

In steel mills filtering grimy, oily cooling and descaling water are common as are those in the automotive and plastics industries. Cement plants and mining operations use this type of filter for removing solids from tailings. They are found on deep-sea oil platforms for filtering flood water and on ships before portable desalination systems. In paint and viscous fluid filtration, a Piston design is used alongwith axial wedge wire screens

• Solvent Bulk filtration before storage
• Paints  (using Piston design)
• Sugar Syrup and Clarified Juice
  
• Wash installations for vegetable clean water re-cycle, corn liquor, etc.
• Process Water, RO pretreatment
• Mining and Cement Mill
• Industrial Waste Water, Cooling tower water
• Protection of pumps and heat-exchangers
• In-take filters from river / lakes