With our high capacity filter basket & bag the filtration surface area is increased by 70%. By placing this filter bag, you can take a smaller and cheaper filter housing, but still have the desired flow rate and dirt holding capacity. This increased dirt holding capacity extends the service life of the filter bag. The liquid enters the filter bag and then passes through the outer surface and through the central core, doubling the flow rate.
The volume of retained liquid is reduced by 30% compared to a standard filter bag, reducing the removal weight, and wasting less product.
Application membrane prefiltration with high capacity filter bags
Our customer has 4-off Reverse Osmosis (RO) units protected by 4 x 2 single bag filter housings with standard length #2 polypropylene filter bags @ 10 microns, 24/7.
The life of these filter bags was very short, which meant that the bags had to be changed out several times a day, resulting in a usage of 32 filter bags per day. (11500 pieces/year ~ €70K/year).
In addition to the cost of the filter bags, the cost of downtime and maintenance was also very high, as the filter bags had to be replaced even during the night shift.
The first step was to replace with our high capacity basket and polypropylene bags in the existing single filter housings. This resulted in changing the filter bags twice a day and using 16 bags.
The cost of the high capacity basket and polypropylene filter bags was recovered within 2 months and after that the savings on the filter bags was € 30,- /day (€ 11.500,- / year). This cost reduction was only material, the cost reduction on maintenance was 3 times higher. This relatively simple conversion using the existing bag filter housings saved the customer ~ € 30K per year.
Single bag replaced with multi bag housing
This was only the first step!
The operators still had to change the filter bags almost every night because the bags were clogged, and the RO plant was continuously backwashing what also resulted in a higher CIP frequency.
This was a big problem for the operators and the cost of personnel during the night was very high.
We were convinced that if we replaced the single bag filters with our DFVB600 multi bag housing each with 4x high capacity baskets and polypropylene filter bags, we would extend the life of the filter bags and therefore greatly reduce the need to replace the filter bags. The theory behind this was to increase the total filter area by doubling the number of filter bags resulting in a much lower flux and this results in an increase in filter bag life of up to 4 times or more. To convince the customer we installed our rental Dual Vessel Bag filter unit and conducted a test for several weeks.
Return on investment realized within the first year with our high capacity filter bag
Our customer ordered 4 pieces of combination bag/cartridge filter housings (DFVCB600-50-40-4-2-4), and these were installed in front of the 4x RO units. In addition to the high capacity basket and polypropylene bags, the customer also uses our Twistflow nominal rated string wound filter cartridges which result in even longer life and less maintenance (change outs).
The ROI of this project was realized within the first year. Of course, for us as a supplier of filter consumables not the most profitable, but for the customer a significant reduction in operational costs.
We are convinced that offering the best solution for the customer is the only solution.
If you want to see the high capacity basket and bag in person, please come to the OTC Houston, from May 2-5. Learn more about the OTC here.
Products used in this project
Other available Dutch Filtration products
- Standard Single Filter Houses
- DF00747 – Filter basket, for L2HC bags, SS316
- Filter bags Length #2, PP, 10 micron
- Combination filter housings bags/cartridges
Dutch Filtration gives you
- Improvement of your process and (working) environment
- Saving operational (OPEX) and overall costs
- 24/7 customer service, personal and fast response.