How to Install & Replace Filter Bag for FRP Filter Housing?

The FRP bag filter housing is mainly made of epoxy resin and glass fiber material, which is mainly composed of FRP shell, FRP top cover, basket, sealing ring, fixed mount and other components. FRP filter housing have acid and alkali resistance and corrosion resistance, and are often used in the field of liquid filtration with high salt content such as brackish water and seawater desalination. Let's learn more about FRP bag filter housing together.

What Type of FRP Bag Filter Housings Hongtek Supply?

The FRP bag filter housing now are widely used in various liquid filtration fields with high salt content. In order to better meet the needs of water flow and floor space requirements in different filtration fields, we provide single filter bag housing and multi bag filter housing.

1. FRP Single Bag Filter Housing

The FRP single bag filter housing is equipped with a size #2 Filter Bag, which can be installed in a mobile nanofiltration or reverse osmosis device to act as a pre-filtration part of nanofiltration or reverse osmosis. It's also possible to combine multiple single bag filter housing in parallel to form a pre-filtration device according to the requirements of water flow.

2. FRP Multi Bag Filter Housing

The multi bag FRP filter housing can be installed with 3pcs, 4pcs, 5pcs, 6pcs or 7pcs size #2 Filter Bags. When designing the filter system, the appropriate type of FRP filter can be selected according to the requirements of water flow rate. It's also possible to freely combine multiple multi bag filter housing into a filtration device in parallel, so as to meet the requirements of water flow in the system.

Installation and Replacement Guide for FRP Bag Filtration System

FRP bag filtration system usually consists of a single/multi bag filter housing directly, or is composed of multiple single/multi bag filter housing in parallel. The installation and replacement steps of single and multi bag FRP filtration systems are roughly the same. Let's take a look at the installation and replacement steps of bag FRP filtration systems.

1) Before installing the bag filter housing, verify that the filter housing specifications meet the requirements and ensure that the housing surface and various parts are not damaged. Then take out the pressure gauge, exhaust valve, fixed mount, basket and other parts in the housing, and install the exhaust valve, drain valve and pressure gauge on the housing;

2) Close the FRP filtration system, and close the upstream inlet valve and downstream outlet valve of the housing. If one single/multi bag filter housing is installed, directly connect the clamp/flange/thread of the inlet/outlet with the inlet/outlet pipes are connected and tightened. If installing multiple bag filter housing, first assemble multiple housing in parallel, and then connect the clamp/flanges/threads of the housing inlet/outlet to the inlet/outlet pipe respectively;

3) If the filter bag is installed, rinse the inside of the housing with water directly, and then discharge the sewage from the drain outlet. After the sewage is exhausted, close the drain valve tightly. If you want to replace the filter bag, you need to open the exhaust valve of the housing for pressure relief treatment, then open the cover on the top of housing, take out the filter bag that needs to be replaced, and then rinse the inside of the housing with clean water. After the drain outlet is exhausted, close the drain valve tightly;

4) Unpack the filter bag, check and make sure that the filter bag meets the requirements for use. First install the basket vertically into the housing, and then put the filter bag into the basket, so that the plastic ring/steel ring of the filter bag fully fit with the groove in the housing, then put on and tighten the fixing mount;

5) Cover the lid on the top of the housing, tighten the swing bolt to make the cover completely fixed on the housing to achieve the sealing effect;

6) Start the bag filtration system, slightly open the inlet valve upstream of the housing, let the liquid enter the housing, close the exhaust valve until the liquid fills the housing and overflows from the exhaust port;

7) Slowly open the outlet valve downstream of the housing until it is fully open, and then slowly adjust the inlet valve upstream of the FRP housing until the pressure difference between the upstream and downstream of the housing reaches the initial pressure difference of the filter bag.          

Precautions for Installation and Replacement of FRP Bag Filtration System

1) Ensure that there is no liquid leakage and good sealing at the connection positions of the pressure gauge, exhaust valve/pressure relief valve, drain valve, and inlet/outlet flange of the FRP filter housing, otherwise the working efficiency of the housing will be reduced;

2) When replacing the filter bag, before opening the cover, you must first open the exhaust valve/ pressure relief valve on the top of the housing to relieve the pressure of the housing, otherwise the operator may be injured due to excessive internal pressure of the housing;

3) When installing the FRP bag filter housing, it should be ensured that the connection direction of the inlet/outlet flange of the housing and the inlet/outlet pipe is correct. If the connection direction is wrong, the filtration system will lose its filtering function and can also cause irreversible damage to the filter bag;

4) In order to avoid the fact that the liquid flow can not meet the requirements of the system and reduce the working efficiency of the filter system, when the pressure difference between the upstream and downstream pressure gauges of the filter reaches the specified replacement pressure different of the filter bag, the filter bag should be replaced in time.