Inline Automatic Filter

Our company has completed prototype development work on self-cleaning inline automatic filter units and has begun product trials at several customer facilities. Detailed information regarding this new unit is shared below. General Information on Inline Automatic Filter: What is it? A liquid filter developed to enable solid particles in liquids produced in industrial facilities to be filtered and the product obtained within the desired micron range, so that liquid products or semi-finished products can pass quality control criteria before being transferred to storage tanks and/or packaging. This filter is attached to the pipe line through which liquid is transported; the liquid product enters the filter and exits filtered; there is no need for any intermediate holding tank before or after filtration. Its dimensions have been optimized, thus occupying minimal space in the facility. The filter element inside the filter body can perform minimum 25 micron filtration. Its most important feature is that the filter has self-cleaning capability. Thanks to this, there is no continuous need to replace filter elements (cartridges, filter cloths, etc.). This results in significant operational cost advantages due to savings on consumables, and additionally, since there is no filter element replacement operation, production time losses in the facility are avoided.

Where is it used?

It is used effectively in all facilities producing liquid and semi-finished products, as well as in all facilities that use liquid semi-finished products in their production and wish to filter before adding to the process. It can be easily used in all sectors where liquid products require filtration, particularly paints, resins, textile chemicals, food products, and chemical products. Production capacity may vary depending on the maximum permitted particle size in the finished product after filtration and the product viscosity.

System Operating Principle:

Figure 1 shows the front view of the inline automatic filter. To describe the filter sections in general terms: • Liquid product to be filtered enters the filter system from the upper left; • The liquid passing through an automatically controlled spherical valve at the top right enters the filter body; • This automatically controlled valve positioned before the filter cuts off liquid flow from the main line during maintenance and cleaning. • Inside the filter body there is a filter element manufactured from stainless steel in the shape of a cylinder open at top and bottom. [caption id="attachment_136828" align="aligncenter"] Figure 1: Filter General View.[/caption] The liquid to be filtered is filtered through micro pores from the inner surface to the outer surface of the filter element. • The filtered liquid exits from the right side of the body and continues to the process. • Particles that cannot pass through the filter begin to accumulate on the inner surface of the filter. • Through pressure gauges located at the inlet and outlet of the filter body, the pressure differential in the filter is measured; when it exceeds the set value, the pneumatic piston on the filter body engages, the cleaning disk that scrapes the inner surface of the filter element moves up and down, and thus particles accumulated on the inner surface of the filter are scraped away and accumulate in the lower cone of the filter body. Depending on the contamination level of the product to be filtered, accumulated particles are automatically transferred to the bypass line after a certain period by momentarily opening the valve below the cone. Products passing through the coarse filter in the bypass line are passed through a gear pump to be fed back to the product inlet line. The purpose of the bypass system is to transfer products that escape unfiltered during discharge back to the filter inlet. • Along the line extending from the bottom of the filter to the right, coarse particles reach a stationary coarse filter where some of the coarse particles are retained. • Coarse particles accumulated inside the stationary coarse filter must be cleaned manually at regular intervals. • The automatic filter cleaning operation we are attempting to describe takes place over a very short time period. Even during this time, the filter system continues normal product filtration. • After the automatic cleaning operation, the valve below the filter closes, the gear pump stops, and the filter system resumes normal operation. • The filter's automatic self-cleaning operation is achieved through pressure sensors, automatically controlled valves, and a PLC-controlled automation system that controls all these electronic devices.

Technical Details of System and Equipment:

• All metal components, particularly those in contact with liquid product, will be determined based on the chemical properties of the liquid to be filtered and the hygiene conditions of the facility. • Metal components in contact with product will be manufactured from AISI304 material. • Pipe connections are generally preferred as flanged type. Automatically controlled spherical valves are part of the automatic control system and are mounted in the system especially to facilitate disassembly of equipment during maintenance and cleaning. • Pressure sensing sensors measure the pressure at inlet and outlet and send data to the automation system for calculation of pressure differential; simultaneously, the pressures at different points in the system can be observed with analog pressure gauges mounted in the system. • The filter element is mounted inside the filter body in a completely leak-proof manner with the help of gaskets located on the upper and lower flanges of the filter element. The filter element inside the filter body has been specially designed and is manufactured entirely from stainless steel wires with pyramid cross-section. • Thanks to the pyramid cross-section steel wires, effective filtration is achieved, particles passing through the filter slots easily move away from the system without experiencing re-compression, and thus the filter clogging problem does not occur in this filter system.   [caption id="attachment_136831" align="aligncenter"] Figure 3: Stainless Steel Filter Element General View[/caption] [caption id="attachment_136833" align="aligncenter"] Figure 4: Stainless Steel Filter Element Detail View[/caption] Solid particles that cannot pass through the filter element slots begin to accumulate on the inner surface of the filter; the pressures detected by the digital pressure sensors at the filter inlet and outlet have their difference continuously calculated by means of the automation system, and when the limit value is exceeded, the PLC system initiates the automatic self-cleaning procedure. • Upon initiation of the automatic filter cleaning procedure, simultaneously the automatically controlled discharge valve below the filter opens, the filter scraper mechanism begins to rotate and discharge accumulated particles from below the filter, at the same time the gear pump operates and feeds the liquid passing through the coarse filter back to the main filter inlet line. • The automatic filter cleaning procedure is a very brief operation; filtration continues during filter cleaning, only some unfiltered liquid along with coarse particles escapes to the discharge system; this escaped liquid is returned to the system for filtration. • There is also a filter with relatively larger pores in the stationary (coarse) filter. The stationary filter has no automatic cleaning system; therefore, particles retained here must be cleaned manually at regular intervals. • The gear pump positioned after the stationary filter further increases the pressure of the liquid at a pressure equal to system pressure in the discharge line, enabling the liquid to be easily injected into the 'T' connection in the main line. • System working pressure, inlet-outlet pressure differential limit value, filtration flow rate, system working temperature, product viscosity, filtered product average particle size, and similar parameters vary according to each facility and each product. • Our inline automatic filter system provides filtration down to minimum 25 micron particle size. • This filter can be used in liquid lines operating at maximum 16 bar pressure. • This filter system has been designed to be resistant to filtration of liquid products at maximum 200°C temperature. Advantages Over Classical Filtration Systems • In classical systems, cloth filters or cartridge filters must be changed frequently, whereas in our system the filter element can be used for many years. This provides both savings on consumables and, since there is no filter element replacement time, no production disruptions and time losses occur. More production is achieved compared to classical systems. • Since the filter continuously cleans itself in this system, consistently high-quality product is obtained. • Since the filter has no clogging problem, the process pumps pressurizing the main line are not strained, and thus energy savings are achieved. • Particularly the surfaces of the filter in contact with liquid can be easily disassembled, maintained and cleaned, and remounted in a short time.

Yiğit Dölen General Manager Zirve Proses