Frac Sand & Proppant Processing Equipment

Wet processing and dry classification routes that turn your silica deposit into in-spec proppant at the lowest cost per tonne.

Frac sand processing turns raw silica deposits into proppant that meets API RP 19C and ISO 13503-2: at least 90% of grains between the designating sieves, under 0.1% oversize and under 1% fines. CFlo builds both wet washing circuits and water-free dry classification plants, field-validated at 91.6% saleable yield.

What defines a frac sand

Frac sand is a proppant: pumped into a fractured reservoir, it must hold the fracture open under closure stress while letting hydrocarbons flow. That places tight demands on the processed product:

Particle size distribution: a minimum of 90% of the tested sample must fall between the two designating sieves for the grade (20/40, 30/50, 40/70, 70/140). Not more than 0.1% may be coarser than the coarse designating sieve, and not more than 1% finer than the fine designating sieve
Sphericity and roundness: premium grades need well-rounded, near-spherical grains so the proppant pack stays conductive under load
Crush resistance, turbidity and acid solubility: clay, silt and surface coatings must be removed to meet the limits of API RP 19C and ISO 13503-2

The recurring engineering challenge is making a precise top-size and bottom-size cut, then removing residual fines below the bottom sieve, repeatably, at production rate.

Route 1: wet processing

Where the feed carries clay, silt or surface coatings, or needs both a sharp size cut and a wash, the wet circuit is the proven route. CFlo builds the complete modular design: feed preparation, attrition scrubbing to liberate clay and strip coatings, upward-flow hydraulic classification to lift oversize and undersize away from the in-spec fraction, fine sand recovery, and high-frequency dewatering screens configurable for more than one dewatered product at once. Cyclones and our water treatment range recover ultra-fines from the classifier overflow and return clarified water to the circuit, so a wet frac sand plant can run close to Zero-Liquid Discharge, recycling up to 95% of process water, even on a tight water budget.

Route 2: dry classification with the Aerograder

Many frac sand deposits, particularly in desert and arid basins, arrive already dry and largely clean. A full wet circuit then adds cost, water and footprint the material does not need. For these feeds CFlo deploys the Aerograder air classifier: a precise fines cut with no water, no cyclone, no baghouse and no airlock. The Aerograder takes feed below 5 mm at 1–2% surface moisture and cuts cleanly in the 75–100 micron region, exactly where operators must meet the sub-1% bottom-size limit.

The dry route is right when water is scarce, expensive or not permitted for discharge; when the feed is already dry and free of bonded clay; when the job is fundamentally a precise fines cut rather than a wash; and when lowest operating cost and smallest footprint are decisive.

Field validation in the GCC

A frac sand operation in the GCC commissioned a CFlo dry classification line running four Aerograder units in parallel. The validated field test delivered:

91.6% saleable product yield
94.7% coarse recovery above 106 micron
0.94% residual fines, inside the sub-1% bottom-size limit (PASS)
Cut performance of d50 = 43 micron and d25 = 101 micron

Achieved with no process water, in a basin where water cannot be spared, this result is now the calibration reference for CFlo's frac sand process modelling.

Reference grades and sieve nests

CFlo works to the standard frac sand designations: 6/12 (3.36–1.68 mm), 8/16 (2.38–1.19 mm), 12/20 (1.68 mm–841 micron), 16/30 (1.19 mm–595 micron), 20/40 (841–420 micron), 30/50 (595–297 micron), 40/70 (420–210 micron) and 70/140 (210–105 micron), each tested on the recommended USA sieve nest. Micrograder (wet) and Aerograder (dry) plants are engineered as Next-Gen 'Super' Systems: Super modular for fast deployment to remote basins, Super smart process control that holds spec while minimising water and power, Super easy app-guided installation and service.

FAQs

Frequently asked questions

What specification does frac sand have to meet?

Under API RP 19C and ISO 13503-2, at least 90% of the tested sample must fall between the grade's designating sieves (for example 20/40 or 40/70), with no more than 0.1% coarser than the top sieve and no more than 1% finer than the bottom sieve, plus sphericity, roundness, crush-resistance, turbidity and acid-solubility limits.

Can frac sand be processed without water?

Yes. CFlo's Aerograder air classifier makes the fines cut with no water, no cyclone, no baghouse and no airlock. It accepts feed below 5 mm at 1–2% surface moisture and cuts in the 75–100 micron region. A GCC installation achieved 0.94% residual fines and 91.6% saleable yield entirely dry.

When do I need a wet circuit instead of dry classification?

Choose wet processing when the deposit carries clay, silt or surface coatings that must be scrubbed off to meet turbidity and crush limits, or when you need both a wash and a sharp size cut. Attrition scrubbing, hydraulic classification and dewatering screens deliver that; dry classification suits clean, already-dry desert feeds.

How much water does a wet frac sand plant recycle?

With cyclones recovering ultra-fines from the classifier overflow and CFlo's water treatment range returning clarified water to the circuit, a wet frac sand plant can run close to Zero-Liquid Discharge, recycling up to 95% of process water, workable even in arid, water-stressed basins.

What throughput and yield can a dry classification line achieve?

The GCC reference installation runs four Aerograder units in parallel against a combined throughput target. In the validated field test the units delivered 91.6% saleable product yield and 94.7% coarse recovery above 106 micron, with cut performance of d50 = 43 micron and d25 = 101 micron.

Which frac sand grades can a CFlo plant produce?

All standard designations: 6/12, 8/16, 12/20, 16/30, 20/40, 30/50, 40/70 and 70/140 mesh, spanning 3.36 mm down to 105 micron. Each plant is designed around your feed's particle size distribution and the grades you intend to sell, with high-frequency screens configurable for multiple simultaneous dewatered products.

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