General Filtration, Division of Lee Chemicals Limited
General Filtration, founded in 1955, specializes in the application of microfiltration technologies to industrial processes, potable and process water, and waste treatments. The company is pre-eminent as a stocking distributor of filteraids, filter cartridges, membranes, papers, pads, natural, synthetic and non-woven fabrics, as well as powdered and granular activated carbons. We apply applies filtration equipment, ranging from single cartridge in-line housings to fully automated, high volume, turnkey filter stations, based on pressure leaf filters or filter presses.
Our base of applications knowledge frequently allows us to minimize industrial waste by recycling the use of filteraid or filter media in the process itself. Recycling of filtration residues is increasingly promoted in the applications they serve.
Our technical sales group of five persons is supported by an additional six office and warehouse staff. At present, our sphere of operations is mainly within Canada.
Company Details
Company Information
Paul Lawrence
Title:
President
Area of Responsibility:
Management Executive
Telephone:
(905) 761-9000
Fax:
(905) 761-9001
Email:
Click Here
Ed Bridge
Title:
Manager
Telephone:
(905) 761-9000
Fax:
(905) 761-9001
Email:
Click Here
Products
Environmental Products And Services
Automatic Sludge Dewatering Filter.
Pressure leaf filters have been widely installed in the process industries because they provide for fine clarification of liquids with a high degree of automatability. Most of these installations sluice out their spent filter cakes as a slurry with over 90% moisture content. Except for the environmental inacceptability of their sluicings, these installations could still enjoy a long service life.
The Oberlin Automatic Pressure Filter is a fully automated, single-chamber unit which rapidly forms filter cakes on a recleanable belt, dewaters them by blowing down with compressed air or an inert gas, and discharges them at a dry-handleable 40-50% solids.
The Oberlin filter is compact and easily integrated into an existing filter station. The filter is constructed of mild steel with a wide range of coatings for process compatibility, or with stainless steel wetted parts. Highly efficient cake washing can be carried out for decontamination of the solid residue or for recovery of valuable liquid. The filter can be operated with sub-micron rated filter media such as Tyvek® in critical clarity applications.
Laboratory testing and rental of pilot units are available for the evaluation of applications.
Perlite Or Solka-floc Filteraids As Replacements For Diatomite.
Diatomaceous earth, widely-known and long-used as a filteraid in process and waste filtrations, has a high microcrystalline silica content. As well as being a respiratory hazard in the workplace, the silica is being scrutinized in some jurisdictions as a potentially hazardous dust in landfills in which spent filter cakes are deposited.
Perlite and Solka-floc are finely divided powders manufactured from a volcanic mineral and from wood pulp respectively, which have filtration properties very similar to those of diatomite. Like diatomite, they are inert to a wide range of process liquids. Like diatomite, they are available in a range of particle-size distributions to give the desired clarity and flowrate in different applications. On a cost-of-use basis, they are as economical as, or more economical than, diatomite.
Although less known than diatomite, these products have been in wide use for many years so that there exists a sound body of applications knowledge upon which to base grade selection, dosage, and procedures. Perlite and Solka-floc have the same availability in bagged, semi-bulk, or bulk formats as diatomite.
Perlite Filteraid Precoat.
Filter presses used to dewater sludge in industrial wastewater treatments usually suffer severely sub-optimal performance as fine particles blind their cloths after a brief period in service. Even sophisticated synthetic fabrics selected for their cake release properties are subject to blinding, and cake adhesion especially by metal hydroxide sludges or flocked oil and grease. As a result, high labour costs for manual press cleaning are incurred. In some cases the filter press is bypassed, or sludge with high moisture content is trucked away to a special treatment facility, representing a heightened environmental danger during transport and, again, excessive cost.
A precoat of perlite filteraid applied to the filter septum with clean water before the introduction of the sludge protects the cloth from blinding, and permits long filter cycles. Because the filter chambers can now be completely filled, dewatering performance is greatly enhanced. With the precoat acting as a release agent, the well-dried cakes fall readily with minimal manual cleaning of the press.
In some cases, the optimization of an existing press by precoating avoids the necessity of buying more filter capacity as a waste treatment plant expands.
Perlite filteraid is a finely-divided powder manufactured from an inert volcanic mineral. It is selected in preference to the better-known diatomite because it has less than 0.1% microcrystalline silica, and thus is not considered a workplace hazardous material. The correct grade and dose of perlite, as well as an effective application procedure, are determined with the help of a well-trained technical staff.
Services