Filter blinding
Fine, compressible solids such as yeast, gums and colloids quickly seal filter cloths and screens. Pressure rises, flow falls and filters must be stopped and cleaned far too often.
Industry · Filtration
Diatomaceous Earth Filter Aids for Industrial Filtration
Porous diatomite filter aids and adsorbent clays for beverage, chemical, oil and pool filtration, supplied with batch test data.
ISO 9001 certified processes
NABL-accredited lab testing
CoA, TDS & MSDS with every shipment
Export packaging worldwide
Overview
Minerals engineered for filtration
Diatomaceous earth filter aids form a porous, rigid filter cake that captures fine particles which would otherwise blind a filter cloth or screen. Obsidian Minerals supplies diatomaceous earth for precoat and body-feed filtration in beverage, chemical, industrial liquid and swimming pool applications, together with bleaching earth for adsorptive purification.
Diatomite consists of the fossilised silica skeletons of diatoms. Each particle is full of microscopic pores and has an irregular, interlocking shape, so a cake built from it is mostly open space. That structure lets liquid pass while trapping solids at micron scale. In practice, a thin precoat is laid on the filter septum, and further filter aid is dosed into the liquid as body feed, keeping the cake permeable as solids accumulate. Grade selection balances clarity against flow rate: finer grades capture smaller particles but filter more slowly. Where colour, odour or dissolved impurities must be removed rather than just particles, an adsorbent such as acid-activated bleaching earth is used alongside or ahead of mechanical filtration.
We supply filter and granular grades of diatomaceous earth, and bleaching earth grades for oil and liquid purification, each tested in an NABL-accredited laboratory with a TDS and batch CoA. Customers should confirm suitability for food or beverage contact in their market. Samples are available for filter trials.
Problems we help solve
Clarity versus throughput
Tighter filtration improves clarity but reduces flow. Operators need a filter aid range that lets them set the balance between product clarity and plant capacity for each liquid.
Dissolved impurities and colour
Mechanical filtration removes particles, not dissolved colour bodies, soaps or trace contaminants. Many processes need an adsorbent step to reach the required purity before final polishing.
Consistent cake performance
Variation in filter aid particle size or density changes cake permeability and run length. Consistent material keeps cycle times, dosage and filtrate quality predictable from batch to batch.
Recommended products for Filtration
Diatomaceous Earth
Filter Grade Diatomaceous Earth
Diatomaceous earth filter aid for precoat and body feed in beverage, chemical and industrial liquid filtration, forming a porous cake that retains fine solids while maintaining flow.
View grade specs
Diatomaceous Earth
Granular Grade Diatomaceous Earth
Granular diatomaceous earth used as an adsorbent and filtration medium where a coarser, free-draining particle is needed, for example in packed beds and absorbent duties.
View grade specs
Bleaching Earth
High Activity Bleaching Earth
High activity acid-activated clay for purifying mineral oils and industrial liquids, adsorbing colour bodies and polar impurities before or alongside mechanical filtration to reach the target purity.
View grade specs
Bleaching Earth
Standard Bleaching Earth
Standard bleaching earth for adsorptive purification of edible oils and fats, removing colour, soaps and trace metals, followed by filtration to separate the spent clay from the oil.
View grade specsFiltration — common questions
How does diatomaceous earth work as a filter aid?
Diatomaceous earth particles are porous silica skeletons with irregular shapes that do not pack tightly. When deposited on a filter septum they form a rigid, highly porous cake that traps fine solids in its pores and on its surface while liquid flows through. Because the cake stays permeable, filtration runs last longer than with cloth or screens alone.
What is the difference between precoat and body feed?
Precoat is a thin initial layer of filter aid deposited on the septum before filtration starts; it protects the cloth and gives immediate clarity. Body feed is filter aid dosed continuously into the unfiltered liquid, so that new solids are trapped within a permeable structure instead of sealing the cake surface. Most systems use both.
Can diatomaceous earth be used in swimming pool filters?
Yes. Diatomaceous earth is used in DE-type pool filters, where it coats the filter grids and traps fine particles to give clear water. The quantity and recharge interval depend on the filter model and size, so follow the filter manufacturer's instructions. Wear suitable respiratory protection when handling the dry powder, as described in the SDS.
Which diatomaceous earth grade gives clearer filtrate?
Finer filter grades capture smaller particles and give clearer filtrate, but they reduce flow rate and shorten run length. Coarser grades filter faster but allow more fine particles through. The right grade depends on your liquid, the solids present and your clarity target, and is best chosen through filtration trials on your own process stream.
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Talk to a filtration specialist
Describe your process and current material. We will recommend a grade, share the datasheet and arrange samples for trial.