Micrograder Plants for UK Silica Sand and China Clay
Grading to a tested specification, not washing until the material looks clean.
The Micrograder is a wet processing plant for the precision end of the sand market: glass sand, foundry sand, filtration media and china clay. It grades to a narrow specification rather than simply washing, controls iron and the fine fraction, and recovers the by-product sand that a china clay or quarry operation would otherwise tip. In the United Kingdom it is supplied and supported by CFlo Europe Limited in Belfast.
A different job from washing aggregate
An aggregate wash plant is judged on how clean the stone is. A Micrograder is judged on whether the product falls inside a tested band: the grading, the silica content, the iron level, the fines.
That changes what the plant has to do. Attrition scrubbing removes the surface coatings that carry iron and clay. Classification places the cut points precisely rather than approximately. Dewatering delivers the product at a moisture the next process can accept. On these duties the specification is the product, so the process is built around holding it.
China clay, and the sand that comes with it
British china clay production is concentrated in Cornwall, and it has always produced far more sand than clay. That sand sits in tips, and for most of the industry's history it has been treated as overburden with a local market for fill at best.
It is silica sand. Whether it is worth more than fill depends on what the grading and the iron content are after processing, which is exactly the question a Micrograder answers. Two products come off one plant: better recovery of the clay itself, and a graded sand from what was waste.
That is not theoretical. At Bhuj in Gujarat a Micrograder BT50 raised china clay recovery fivefold for Suraj Minerals and produced glass-grade silica sand from the same plant. See also china clay and kaolin processing.
Silica sand: the value is at the purity end
The United Kingdom produces silica sand from several districts, and much of it goes to construction, sports and leisure and agriculture. The grades that command a premium are the ones with the tightest specifications: container and float glass, low-iron sand for solar glass, filtration media, and foundry sand. High purity quartz is imported into the UK for some of those uses.
Moving a deposit up that ladder is a beneficiation problem, not a washing problem. Commercial soda-lime-silica glass runs at 70 to 74% silicon dioxide, and low-iron grades for photovoltaic glass demand tighter iron limits again. Whether a given deposit reaches those levels depends on the mineralogy and on how the iron is carried, which testwork establishes.
Proven on the duty: Chu Lai in Vietnam produces float glass sand at 99.3% silicon dioxide, and Saint-Gobain takes glass-grade sand recovered from lignite overburden. See also silica and glass sand processing.
Foundry sand, graded to a fineness number
UK foundries buy moulding sand on grading and fineness rather than on cleanliness alone, and the plant has to hold that batch to batch. A Micrograder in Gujarat produces AFS 50 to 55 foundry sand at 100 tonnes per hour on a modular plant with no liquid discharge.
Reclaiming used foundry sand rather than producing virgin sand is a related but separate duty. See waste foundry sand and foundry sand.
Filtration media and the other specification markets
Water treatment filter media is graded to a defined size range and uniformity coefficient, which is a classification duty rather than a washing one. The same applies to sports sand, horticultural sand and glass-fibre grades. Where the specification is narrow and tested, the Micrograder is the platform.
Water, and what leaves the site
The Micrograder recycles water in the same way as the rest of the range, and on the finer duties this matters more, because the material generates a fine sludge in volume. The Easysettle sludge bay manager rigidifies tailings at the point of disposal so water is released immediately and the lagoon footprint stays small. Where consent conditions or the site's footprint rule lagoons out, mechanical dewatering is specified instead.
Sizing it, and who supports it
Models run from the Micrograder BT50 up to the Micrograder Exo, configured for the deposit rather than picked from a table, because on these duties the mineralogy decides the arrangement. Sizing starts with a sample at our material testing lab, where the achievable grading, silica content and iron level are established before anything is quoted. The lab is DSIR-accredited, runs pilot units on bulk samples rather than bench tests, and assays the finished product.
Pre-Engineering then turns that result into a complete engineering package, designed against your deposit: process flow, mass balance, layout and equipment schedule. On a specification duty this is where the plant is actually decided, and it can run while permitting is still in progress.
Plants are CE and UKCA marked, and in the United Kingdom they are sold, installed and supported by CFlo Europe Limited in Belfast. We will be at Hillhead 2026.
Send us a sample
Tell us about the material and an engineer will come back with how much to send, how to sample it, and what the programme would cover.
A frac sand plant being delivered from Belfast
The Micrograder is in manufacture for a frac sand project near Darwin in Australia, where the sand has until now been hauled in by road from more than a thousand kilometres away. Delivery is managed by the CFlo Europe team, and commissioning is scheduled for early next year. The project announcement sets out what the plant has to hold.
Oceania sits in the same territory as the UK and Europe, so the people running that project are the people who would run yours.
Who you deal with in the UK
Specification duties need engineers who will argue about an iron level rather than quote a throughput, and they need to be reachable. CFlo Europe Limited covers the UK and Europe from Belfast, and Aggregates Business set out the expansion and the thinking behind it in a feature in August 2026.
A career spent building wet processing plant for quarries in Britain and Ireland, having previously helped build a global wet processing brand.
What we need from you to quote
A representative sample, a recent analysis if you have one, the specification you are trying to reach, the tonnes per hour, and what you currently do with the fines and the by-product sand. On a china clay site, the tonnage and grading of the sand fraction matters as much as the clay.
See it in action
Frequently asked questions
What does the Micrograder do that a wash plant does not?
It grades to a specification rather than washing to a standard of cleanliness. Attrition scrubbing removes the coatings that carry iron and clay, classification places the cut points precisely, and the plant is built to hold a narrow band batch to batch. On glass, foundry and filtration grades the specification is the product.
Can it recover saleable sand from china clay waste?
That is one of its main duties. A china clay operation produces far more sand than clay, and whether that sand is worth more than fill depends on its grading and iron content once processed. At Bhuj in Gujarat the same plant raised clay recovery fivefold and produced glass-grade silica sand from the by-product.
Will it get our deposit to glass grade?
That depends on the mineralogy, particularly how the iron is carried. Commercial soda-lime-silica glass runs at 70 to 74% silicon dioxide, and low-iron solar grades are tighter again. Plants of this type have reached 99.3% silicon dioxide on float glass sand in Vietnam. What your deposit reaches is a testwork question rather than a claim, which is why sizing starts with a sample.
Does it produce foundry sand to a fineness number?
Yes. Foundry sand is bought on grading and AFS fineness, and holding that consistently is a classification duty. A Micrograder in Gujarat produces AFS 50 to 55 at 100 tonnes per hour with no liquid discharge.
What happens to the fines?
They leave as tailings, rigidified at the point of disposal by the Easysettle sludge bay manager so water releases immediately and the volume to remove stays small. Recycled water returns to the plant. Mechanical dewatering replaces lagoons where the site or its consent will not accommodate them.
Who supplies and supports the Micrograder in the UK?
CFlo Europe Limited, based in Belfast, handles UK and European sales, installation and technical support. Plants are CE and UKCA marked. Call +44 78687 88960 or email [email protected], and we will be at Hillhead 2026.