Vacuum Disc Filters
Compositech's rotary vacuum disc filters are used for filtration in many processing industries including pulp and paper mills where they are used as savealls and as stock thickeners. Disc filters are versatile and provide reliable, continuous liquid-solid separation, however they do require major operator attention and a high volume of synthetic wire sector cover replacement due to the high tonnage of abrasive materials being filtered.
Disc filters generally consist of a series of discs made up of individual disc sectors which are covered with woven media and mounted in a row along a horizontal centershaft. These discs rotate on the shaft into a slurry filled tank. The process cycle of the rotary vacuum disc filter is continuous, and each revolution of the disc consists of cake formation, drying and discharge. As each disc sector is submerged in the slurry, a vacuum is applied which pulls the liquid through the cover and into the sector. The liquid then moves through the filtrate ports, the valve, and into the vacuum receiver where the liquid and air are separated. Solids form on the outside of the cover and increase in thickness as the sector rotates through the slurry. Once the sector travels out of the slurry, air and water are drawn through the formed filter cake as drying takes place. The filter cake of de-watered solids is discharged from the cloth as the disc rotates into a discharge repulper.
The rotary vacuum disc filter has several filter cake discharge options:
Low pressure blow discharge: gentle inflation, cake scraped off
Snap blow discharge: high pressure, quick-acting blow
In addition to the vacuum disc filters we manufacture, Compositech supplies improved replacement parts for other disc filter brands. We have a large inventory of parts including centershafts, wear plates, valves, bridging, flex connectors, sectors, clamps and rods, sector covers, tie rods, retainer rings, bearings and bearing liners, screw conveyor bearing housings, stub shafts, air clutches, stainless steel hood doors, knock off shower headers, oscillating shower headers, screw conveyor scrapers, agitators, drive gears and worms, and motors and reducers. We are also able to custom design parts to your specifications.
We stock Compositech designed and manufactured replacement parts for Beloit Jones™, Celleco™, Dorr-Oliver®, Eimco®, GL&V®, IMPCO™, Komline-Sanderson®, and most other brands of vacuum disc filters. Our replacement parts meet or exceed the quality and material of vacuum disc filter OEM components.
Compositech is not an authorized replacement parts supplier or service supplier for GL&V®, Celleco™, Beloit Jones™, IMPCO™, Dorr-Oliver®, Eimco®, or Komline-Sanderson® brands of process equipment or parts therefore; nor is it in any way associated with GL&V USA Inc. or with FLSmidth A/S or their affiliated entities. All Compositech replacement parts are manufactured by and warranted by Compositech and not by the original equipment manufacturer.
Sector Recover Services
Compositech offers two approaches to disc filter sector recovering:
In-Plant Sector Recover Service
Compositech recommends in-plant recovering when a facility chooses to change several rows of sectors regularly as part of a PM schedule. While on-site, Compositech's crew provides the following services:
Remove a predetermined number of sectors from Saveall
Remove the sector covers
Pressure clean to remove residue and fiber build-up
Inspect sectors for broken welds, stress cracks, etc.
Complete minor weld repairs as indicated and approved
Install new covers and steam so the covers shrink to fit
Install recovered sectors with new acid resistant gaskets
Inspect and adjust all clamps, mounting bolts, etc.
While Compositech's crew is at your plant, they also inspect all remaining sectors not scheduled for recover and replace any damaged covers. This preventive maintenance sector recover method provides for a complete scheduled recover of all sectors and minimizes the likelihood of operating the Saveall at less than peak effeciency due to sector problems. We provide all the labor, equipment, tools, and transportation and we always bring along a supply of small parts that may need replacement. Our crew is focused on completing the work within your schedule and we have a Compositech technician on-site until the plant restarts and the Saveall is fully operable.
Factory Sector Recover Service
Factory recovery services are preferred by our customers who have spare sectors in stock and choose to change out sectors when visible damage has occurred. This method results in a cleaner sector body that has been more thoroughly inspected for stress cracks. The cover is installed at our factory using a heat knife to cut the cover to size and using ultrasonic welding to provide a smoother surface and more consistent fit while eliminating stitching and zippers. Compositech provides the following complete sector rebuild services:
Remove sector covers
Pressure clean to remove residue and fiber build-up
Shot blast clean to remove stubborn built up residue
Inspect sectors for broken welds, stress cracks, etc.
Complete minor weld repairs as indicated
Install new covers and steam so the covers shrink to fit
Install acid resistant gaskets on the neck of each sector
Replace hardware,
threaded inserts, clamps, rope ties as needed
Added freight costs for shipping to Compositech's factory are offset by the efficiencies in this type of cover installation if a minimum of 36 sectors are available for each shipment. Our shipping department arranges the pick-up and return of sectors. Just let us know your sectors are ready for transport and we will handle the rest.
Compositech Replacement Centershafts
Compositech manufactures a stainless steel centershaft successfully used by our paper mill clients to replace the cast iron centershaft supplied with most disc filters. The proprietary design of our centershaft features custom made radial rod sockets and tubing for the drive end trunnions. All filtrate tubes and trunnions are 100% seal welded before machining to ensure a smooth, leak free finish. All filtrate tubes are individually removable from the centershaft allowing for easy repair and replacement without requiring complete disassembly of the filter. We design our centershafts to meet or exceed the quality of the original equipment manufacturer. Most recently, we built a replacement centershaft for an Eimco® disc filter. This Compositech designed and manufactured centershaft, pictured below, measures 33 inches in diameter with a length of 28 feet, 9 inches.