bag type dual filter Bag Filter Stainless steel Filter | DOVMXTECH

Bag filter is a new type of filtration system with novel structure, small volume, easy and flexible operation, energy-saving, efficient, airtight operation, and strong applicability. The interior of the bag filter is supported by a metal mesh basket, and the liquid flows in from the inlet. After being filtered by the filter bag, it flows out from the outlet. Impurities are intercepted in the filter bag, and can be reused after replacing the filter bag.

DOVMXtech Bag filter is specially optimized for filtration of oil liquids.

DOVMXtech bag filter consists of three parts: a filter cartridge, a filter basket, and a filter bag, with a compact and simple structure; The liquid to be filtered enters through the inlet of the filter and flows into the filter bag. After being intercepted by the filter bag, it flows out through the outlet of the filter. The inlet and outlet design of bag filters generally adopts a side in bottom out method, which is convenient for cleaning.

DOVMXtech stainless steel bag filter are used in food and beverage, beer and Baijiu engineering, fine chemical engineering, biological pharmaceutical engineering, water treatment engineering and many other fields. It is a good filter with the advantages of convenient operation, corrosion resistance, strong production capacity, convenient cleaning. 

DOVMXtech Bag Filter:

Bag filter is a pressure type filtration device, mainly composed of filter cylinder body, filter cylinder cover and quick opening mechanism, stainless steel filter bag reinforcement net and other main components. The filtrate flows into the filter bag through the side inlet pipe of the filter shell, and the filter bag itself is installed in the reinforcement net basket. The liquid can penetrate through the filter bag with the required fineness level to obtain qualified filtrate, and impurity particles are intercepted by the filter bag. This machine is very convenient for replacing filter bags, and there is almost no material consumption during filtration.

DOVMXtech Bag filters have many advantages, such as reasonable structure, good sealing, strong circulation ability, and easy operation. Especially, the probability of side leakage of the filter bag is low, which can correctly ensure the filtration accuracy and quickly replace the filter bag, resulting in a decrease in operating costs. The internal and external surfaces of the filter are mechanically sandblasted and polished, which is easy to clean.

Features:

1. The side leakage rate of the filter bag is low, effectively ensuring the filtration quality.

2. Bag filtration can withstand greater working pressure, reduce pressure loss, lower operating costs, and have significant energy-saving effects.

3. The filtering accuracy of the filter bag is constantly improving, reaching 0.5 μ m.

4. Bag filtration has a large processing capacity, small volume, and large capacity for pollutants.

5. Based on the working principle and structure of the bag filter system, it is convenient and fast to replace the filter bag, and the filter is free from cleaning, saving labor and time.

6. The filter bag can be reused after cleaning, saving costs.

7. Bag filter has a wide range of applications, flexible use, and diverse installation methods.

8. The delivery period is 20 days. The warranty is one year.

#1 bag Side Entry Bag Filter Stainless Sanitary Filter

• Overall height : 39 inch
• Outer Diameter : 8 inch
• Fully comply with GMP requirement, professionally mechanical polishing and electrolytic polishing
• Internal polish to be Ra< 0.6 um, external polish to be Ra< 0.8 um
• Maximum operating pressure 90 psi
• Housing material available in stainless 304 and 316L
• O-ring available in EPDM, PTFE, Viton, and Silicone
• Suitable for filtration of beer, syrup, fruit juice, and juice concentrate etc
• Applicable for food & beverage, pharmaceutical, chemical and electronic filtration

#2 bag Side Entry Bag Filter Stainless Sanitary Filter

• The side entry bag filter stainless housing can take #2 filter bag
• Overall height : 54 inch
• Outer Diameter : 8 inch
• Fully comply with GMP requirement, professionally mechanical polishing and electrolytic polishing
• Internal polish to be Ra< 0.6 um,  external polish to be Ra< 0.8 um
• Maximum operating pressure 90 psi
• Housing material available in stainless 304 and 316L
• O-ring available in EPDM, PTFE, Viton, and Silicone
• Suitable for filtration of beer, syrup, fruit juice, and juice concentrate etc
• Applicable for food & beverage, pharmaceutical, chemical and electronic filtration

#4 bag Side Entry Bag Filter Stainless Sanitary Filter

• Overall height : 25 inch
• Outer Diameter : 8 inch
• Fully comply with GMP requirement, professionally mechanical polishing and electrolytic polishing
• Internal polish to be Ra< 0.6 um, external polish to be Ra< 0.8 um
• Maximum operating pressure 90 psi
• Housing material available in stainless 304 and 316L
• O-ring available in EPDM, PTFE, Viton, and Silicone
• Suitable for filtration of beer, syrup, fruit juice, and juice concentrate etc
• Applicable for food & beverage, pharmaceutical, chemical and electronic filtration

Filtering operation and precautions

The bag filter is easy to operate. When in use, simply install the filter bag with the required fineness level inside the filter cartridge, check if the O-ring is intact, and then tighten the ring bolt of the filter cartridge cover to put it into operation. After the pump is started, the pressure gauge on the filter slightly rises, with an initial pressure of about 0.05MPa. As the usage time prolongs, the amount of filter residue in the cylinder gradually increases. When the pressure reaches 0.4MPa, the cylinder cover should be shut down and opened to check the residue situation in the filter bag. The filter bag can be replaced and continued to use (the filter bag can generally be reused after cleaning). The pressure of the filter is generally set between 0.1 and 0.3MPa, which can be adjusted through the return pipeline or the return valve on the pump. Excessive filtration pressure can damage the filter bag and protective net.

1、 Daily use

The filtering system in operation needs to regularly check the pressure difference between the inlet and outlet. When the pressure difference reaches 0.05-0.1Mpa, the filter bag should be replaced in a timely manner to avoid the pressure difference from causing the filter bag to break and the support net to be damaged.

2、 Correctly open the upper cover of the filtered filter

Warning: Do not open the lid of the bag filter under pressure, otherwise residual liquid may spray out and cause liquid loss and personal injury.

Therefore, please strictly follow the following sequence of operations:

1) Close the input valve; When there is pressure at the outlet, close the output valve.

2) After confirming that the pipeline connected to the exhaust valve has been connected to a safe place or suction port (especially when filtering toxic and corrosive liquids), open the exhaust valve again to prevent the liquid from causing harm and pollution to workers and the surrounding environment.

3) Check the pressure gauge and confirm that the internal pressure is 0. At this point, the bag filter should have been separated from the pipeline system.

4) If there is a discharge valve, confirm that the discharge liquid is connected to the recycling point and open the discharge valve; When the remaining liquid in the bag filter flows through the discharge valve, close the discharge valve. This discharge work can be completed in conjunction with the pressurization method.

5) Unscrew the upper cap and lift the upper cap. The multi bag filter needs to be rotated at a certain angle.

3、 Replace the filter bag

1) Efficient filter bags are made of fine fibers, which have weak hydrophilicity. The surface of the fiber will not be wetted by water, so like other filter cartridges made of the same material, other liquids with lower surface tension should be used to wet it before use. Before installation, you must immerse the filter bag in a pre wetting solution that matches the filtered liquid for a few minutes.

2) Make sure to open the upper cover of the bag filter.

3) Place the upper cover firmly and carefully remove the filter bag.

4) Insert a new filter bag, please refer to the installation process.

4、 Monitoring filtration quality

When the liquid input pressure is stable, the filtering quality is closely related to the pressure difference inside the filter bag. If the pressure difference is too large, it indicates that the filtering aperture of the filter bag has been blocked and the filtering speed has decreased. Therefore, we suggest that after the bag filter starts working, the pressure difference should be checked regularly, and the time to replace the filter bag should be determined by the pressure difference displayed on the front and rear pressure gauges. Generally, the filter bag can withstand a pressure of about 0.5-1Kg/cm2 (0.05-0.1Mpa). When the pressure difference reaches this range, the filter bag should be replaced in a timely manner to avoid breakage and affect the filtering effect.

If the pressure difference suddenly drops, immediately stop filtering and check for leaks.

5、 Pressurized discharge of residual liquid

When filtering high viscosity liquids, compressed air can be introduced through the exhaust valve to accelerate residual liquid discharge and shorten waiting time. Please note that the air used for pressurized discharge must be stable and the pressure should not exceed the working pressure of the filter.

The operation steps are as follows:

1) Close the input valve.

2) Open the intake valve.

3) Gas is introduced into the bag filter and pressurized to discharge the remaining liquid.

4) Check the outlet pressure gauge and confirm that the gauge pressure is equal to the compressed air pressure; Confirm that there is no liquid flowing out of the outlet.

5) Close the intake valve.

6) Slowly open the exhaust valve; There is residual liquid spraying from the outlet of the exhaust valve, which must be directed to a safe place or the suction port of the filter.

7) After the compressed air is exhausted, close the exhaust valve. At this point, there should be no pressure inside the filter and the cover can be opened.

6、 Cleaning bag filter

If the Shanghai Runhe bag filter continues to filter the same liquid, it does not need to be cleaned. But if other types of liquids are filtered, the machine needs to be cleaned before use.

VII Ο Maintenance and replacement of O-ring seals

Maintenance: during use Ο The O-ring should be aligned Ο Insert the groove to avoid improper compression Ο Deformation of the O-ring seal; When not filtered, Ο The O-ring must be removed and wiped clean, otherwise the residual liquid will solidify and adhere to its surface, leading to hardening and poor sealing.

Replacement: If Ο The O-ring has aged or damaged, please replace it in a timely manner. When replacing, choose the same model Ο O-ring seal.

Special statement:

1. Under normal use, the filter and support network are guaranteed for one year. If damage is caused due to improper use, it is not covered by the warranty.

2. The maximum design pressure of the standard bag filter is 1.0Mpa, except for special specifications where the recommended maximum working pressure is 0.5Mpa.

3. The maximum design pressure inside the jacket of the bag type jacket filter is 1.0Mpa, and the maximum recommended working pressure is 0.6Mpa.

4. The design pressure of the multi bag filter is 1.0Mpa, and the maximum recommended working pressure is 0.6Mpa.

Please follow the following steps during installation:

1. Place the bag filter on the station that needs to be filtered, connect the inlet and outlet flanges or pipe teeth, and fix them; Block the exhaust port or install an exhaust valve. Clamp type connection for insulation heat source.

2. Gently place the metal inner mesh into the bag filter so that the collar of the inner mesh matches the opening of the bag filter.

3. Place the filter bag so that the ring of the filter bag matches the collar of the metal inner mesh.

4. Will Ο Insert the O-ring seal Ο Groove, Ο The O-ring should not be twisted or deformed, and the multi bag filter machine should buckle the filter bag pressure ring.

5. Grasp the upper cover handle with one hand and the other end of the upper cover with the other hand (multi bag filter rotates the top handwheel)

6. After aligning the upper cover, tighten the two diagonally opposite lifting caps simultaneously, and tighten all lifting caps one by one (insert a short rod into the lifting ring to tighten).

7. Close the exhaust valve installed on the top of the bag filter.

8. Please check if the connecting pipes are secure; Is the working pressure within the allowable range.

9. Open the output valve. Open the heat source inlet valve to raise the filter temperature to the specified temperature.

10. Slowly open the input valve to allow the liquid to slowly flow in and fill the filter, preventing the liquid from suddenly impacting the filter bag and causing it to rupture, and then observe for leaks. If there are no leaks, filtering can begin.

Common faults and solutions

The damaged position of the filter bag is mostly at the bottom of the bag due to material accumulation at the bottom of the equipment, and the generation of material accumulation is mostly caused by equipment failures at the bottom of the bag filter. When the system equipment malfunctions, timely process treatment should be taken and the faulty equipment should be repaired in a timely manner to reduce the long-term accumulation of coal powder materials inside the bag filter, minimize the degree of damage to the bag, and also reduce the difficulty of replacing the bag, Ensure that maintenance is completed in the shortest possible time and process production is restored as soon as possible.

The damaged location of the filter bag

The damaged position of the filter bag occurs in the bag, and the cloth bag is often burnt due to issues with material particle size and material distribution method. There are high-temperature particles of varying sizes in the filtered high-temperature flue gas, with temperatures exceeding 400 degrees Celsius, which cannot be detected by ordinary temperature detectors. The vast majority will settle in the gravity settling chamber, and some high-temperature particles will enter the bag filter through the flue gas duct at high speed with the airflow. If the filter bag is made of polycondensated fibers such as polyester, polypropylene, PPS, etc., when there is less dust on the surface of the filter bag, high-temperature particles will burn through the filter bag and form irregular circular holes. When there is a lot of dust on the surface of the filter bag, high-temperature particles will not burn through the filter bag and will form dark baking marks on the filter bag. This requires operators to strictly control the relevant process indicators during the production process to ensure that the materials meet the relevant process requirements to ensure the stable operation of the equipment.

The damaged position of the filter bag is often at the bag mouth due to faults in the back blowing system. The high backwash pressure of the bag filter and the eccentricity of the nozzle can both lead to this situation. After this situation occurs, the injection system of the bag filter should be checked in a timely manner, and the injection pressure and angle of the injection port should be adjusted to ensure the stable operation of the bag filter.

Method for judging the shrinkage of filter bags

Each type of cloth bag filter material has its own unique molecular composition, and the temperature of use varies greatly. When the temperature limit of the filter material is exceeded, the filter bag will shrink and cannot filter, and even cannot be extracted from the bag cage. There are several types of filter bag shrinkage phenomena in general:

(1) The bag cage in the dust collector is higher than the filter bag, and sometimes it is sprayed onto the blowing pipe, indicating that the filter bag is shrinking;

(2) The inability to remove the bag cage from the filter bag (except for deformation of the filter bag) indicates that the filter bag has contracted;

(3) The bottom of the filter bag is broken by the bag cage, indicating that the filter bag is shrinking;

(4) The color of the filter bag darkens (excluding corrosion).

Filter bag blockage and its countermeasures

(1) The main reasons for clogging of filter bags are high filtration speed, fine dust, sticky dust, poor cleaning of filter bags, sticking of filter bags, condensation, and hardening. If the filtering wind speed of the dust collector exceeds the design standard of the filter bag, it is very easy to cause fine dust in the flue gas to enter the fiber inside the filter bag, leading to an increase in filter bag blockage resistance. The use of membrane coated filter materials, coated filter materials, or pre coating the surface of filter bags is a better method. For sticky dust, it is necessary to reduce the filtering wind speed, increase the pressure of pulse injection, or use offline pulse ash cleaning filter bags. However, a better method is to increase the filtering area, reduce the filtering wind speed, and extend the service life of the filter bags.

(2) The main reasons for poor cleaning of filter bags include frequent cleaning times and long cleaning time. Frequent cleaning times and high cleaning pressure can easily loosen the fiber structure of the filter bag, thereby increasing the blockage of the filter bag by fine dust in the flue gas. If the cleaning time is too long, the initial powder layer on the surface of the filter bag will be cleaned together, resulting in a decrease in the filtering accuracy of the filter bag. If the dust removal time is too short and the dust on the surface of the filter bag is not completely cleaned, the filter will be started immediately, and the dust will gradually accumulate on the surface of the filter bag, thus causing the blockage of the filter bag. To solve this problem, the injection controller can be adjusted after several trial runs.

(3) Moisture is the biggest cause of filter bag blockage, and the reason for containing moisture is usually condensation at low temperatures. Especially when dealing with high-temperature flue gas, the following methods can be used to prevent such situations: avoid improper startup; Avoid starting the machine when the resistance of the dust collector is high; Start the machine below the dew point. The dust collector is prone to problems when operating below the dew point. If the intake air is unevenly distributed, it can easily cause local corrosion of the dust collector shell. Therefore, it should be avoided that the dust collector operates below the dew point. If starting at low temperatures is unavoidable, insulation devices such as steam insulation or electric heating insulation should be used.

(4) Air infiltration. Air infiltration often occurs at the flange, maintenance door, or moving device of the dust collector. If the seal is not tight, external air enters the dust collector. When dealing with high-temperature flue gas, it will create a low-temperature area inside the dust collector, leading to condensation at the low-temperature area, corrosion of the dust collector, and the formation of filter bags or platens

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