Structural components:

Scraper component: The core component of the scraper self-cleaning filter is the scraper, which is usually made of ultra wear-resistant synthetic materials, stainless steel, PTFE, etc. Scrapers are usually equipped with high elasticity springs, which can be precisely extended and retracted, and can tightly adhere to the surface of the filter element, ensuring that they can tightly fit the filter element during rotation and efficiently remove impurities. This structural design enables the scraper to cope with various complex filtration situations, especially for impurities with high viscosity or hardness, with strong scraping ability.

Brush components: The key components of the brush self-cleaning filter are stainless steel brushes or bristle brushes. The brush is driven to rotate by a deceleration motor, and the bristles of the brush need to have a certain degree of hardness and flexibility to ensure effective removal of impurities on the filter element. However, after prolonged use, the bristles may experience wear and deformation, which can affect the cleaning effect.

working principle:

Scraper type: Liquid flows in from the inlet of the filter and flows outward from the inner surface of the filter element, trapping impurities and particles on the inner surface of the filter element. When a certain amount of impurities are intercepted on the surface of the filter element, the cleaning program is executed at a fixed time or according to the set pressure difference. The deceleration motor drives the scraper attached to the inner surface of the filter element to rotate, scraping off the impurities on the inner surface of the filter element. The impurities leave the surface of the filter element along the scraper and fall into the bottom of the filter with the descending liquid. The drain valve is opened at a fixed time to discharge the liquid containing high concentration impurities from the drain outlet.

Brush type: The liquid to be filtered flows into the filter through the inlet and is filtered outward from the metal mesh, with impurities intercepted on the inner surface. When the pressure difference between the inlet and outlet of the filter reaches the set value or the timer reaches the set time, the controller sends a signal to drive the motor to rotate, which drives the brush to rotate and brush down the impurities particles adsorbed on the filter screen, and discharge them from the drain valve with the water flow.

Filtering accuracy:

Scraper type: The filtration accuracy is relatively high, usually ranging from 25-3000 microns, which can filter out finer particles and impurities. For some applications that require high filtration accuracy, such as chemical, pharmaceutical, food and beverage industries, scraper type self-cleaning filters have obvious advantages.

Brush type: Due to the thickness of the bristles and the tightness of contact with the filter element, the filtration accuracy can generally only reach a maximum of about 50-3000 microns, slightly lower than that of the scraper type.

Applicable medium:

Scraper type: suitable for liquids with high viscosity and impurities, such as paint, resin, coatings, oils, egg whites, chocolate, fermentation broth, polymers, jelly, adhesives, etc. For these viscous materials, a scraper can effectively remove impurities attached to the filter element, avoiding the accumulation of impurities and clogging the filter.

Brush type: It is more suitable for filtering water without viscosity or liquids with lower viscosity, such as river water, lake water, seawater, groundwater and other raw water, as well as industrial water with strict viscosity requirements. If used to handle high viscosity media, the bristles may not be able to completely remove impurities, resulting in a decrease in filtration efficiency

Cleaning effect:

Scraper type: The scraper has a high degree of adhesion with the filter element, and has a strong force to remove impurities. It has a better cleaning effect on impurities with strong adhesion and the filter cake layer, and can more thoroughly remove impurities on the filter element, making it less likely to have residual impurities. And the scraping action of the scraper is relatively stable, not affected by the flow of the medium, which can ensure long-term stable cleaning effect.

Brush type: During the rotation process, the brush mainly removes impurities through the movement of the bristles. For some stubborn or sticky impurities, there may be incomplete brushing. Moreover, the bristles may experience wear and tear after long-term use, leading to a gradual decrease in cleaning effectiveness, requiring regular maintenance and replacement of the brush.

Cleaning frequency:

Scraper type: Due to the good scraping effect of the scraper and its suitability for high viscosity media, the accumulation rate of impurities on the filter element is relatively slow, so the cleaning frequency is relatively low. This not only reduces the operating and maintenance costs of the equipment, but also extends the service life of the filter.

Brush type: When dealing with liquids with low viscosity, impurities are prone to accumulate on the filter element, causing a rapid increase in pressure difference. Therefore, the cleaning frequency is relatively high to ensure the normal operation of the filter. If used in high pollution conditions, more frequent cleaning may be required.

Equipment maintenance:

Scraper type: The structure of the scraper is relatively simple and the maintenance cost is low. The material of the scraper has good wear resistance and corrosion resistance, and has a long service life. However, it is necessary to regularly check the wear of the scraper and the elasticity of the spring to ensure that the scraper can work normally. In addition, it is necessary to pay attention to whether the drain outlet at the bottom of the filter is blocked and clean the drain pipe in a timely manner.

Brush type: The brush is a vulnerable part and needs to be replaced regularly, otherwise it will affect the cleaning effect. When replacing the brush, it is necessary to stop the operation, which increases the maintenance time and cost of the equipment. In addition, it is necessary to check the operation of the motor and the wear of the transmission components, which requires a relatively large maintenance workload.

Discharge method:

Scraper type: Generally, the bottom discharge method is used, where impurities accumulate at the bottom of the filter. When discharging, the impurities at the bottom can be completely discharged, and the discharge effect is good.

Brush type: According to the type of impurities (suspended solids, sediment), it can be divided into two methods: upper discharge and bottom discharge. However, the upper discharge method may have incomplete discharge, while the bottom discharge method is relatively more reliable.

Energy consumption:

Scraper type: The scraper requires a certain amount of power to rotate and remove impurities, but due to its relatively simple and direct action, the energy consumption is usually relatively low. Especially when dealing with high viscosity media, the scraper can effectively remove impurities, avoiding the increase in system energy consumption caused by impurity blockage.

Brush type: The motor of the brush type self-cleaning filter needs to drive the brush to rotate continuously, which consumes a certain amount of electricity during operation. And if the bristles are severely worn, the motor needs to overcome greater resistance to drive the brush, which will further increase energy consumption.

Equipment cost:

Scraper type: The manufacturing process of scraper type self-cleaning filters is relatively complex, and the material and processing accuracy requirements of the core component scraper are high, so the initial cost of the equipment is relatively high. However, due to its high filtration accuracy, good cleaning effect, and long service life, it can reduce maintenance costs and the cost of replacing filter elements during long-term use, and may have certain advantages in overall cost.

Brush type: The structure of the brush type self-cleaning filter is relatively simple, the manufacturing process is relatively easy, and the initial cost of the equipment is relatively low. However, due to the need for regular replacement of brushes and the possibility of poor performance when dealing with complex media, the maintenance and replacement costs for long-term use may be higher.

Related article recommendations:

The difference between a primary reverse osmosis device and a secondary reverse osmosis device

Specific introduction of RO membrane filter cartridges in various field

Multi cartridges self-cleaning filter: Overview and Applications