Silicon carbide: the membrane you can clean with anything
The material survives pH 1 to 14, which means strong acid and caustic cleaning stay on the table when flux drops. That single property is why SiC holds its place in mining water, oily water and seawater pre-treatment.
Property by property
| Property | SiC | Alumina | Polymeric (PVDF/PES) |
|---|---|---|---|
| Pure-water flux | ≥2000 LMH/bar | ≈1/3 of SiC | ≈1/20 of SiC |
| pH range | 1–14 | 2–12 | 2–11, narrow with cleaning |
| Hardness | 9.2 Mohs | 9 Mohs | — |
| Contact angle | 0.3° (super-hydrophilic) | 10–40° | 40–80° |
| Cleaning regime | Strong acid and caustic, high temperature | Mild acid/caustic | Limited; oxidants degrade the polymer |
| Quoted life | 20 years (material) | 5–10 years | 2–5 years |
| Weak point | Unit cost, brittleness, needs proper pre-treatment | Lower flux, narrower pH | Cannot be chemically restored |
Elements we make
Tubular for high-solids and high-viscosity duty, flat sheet for seawater pre-treatment at large flow, multi-channel for a high area-to-volume ratio.
| Model | Element | Pore size | Flux (LMH) | Length | Housing |
|---|---|---|---|---|---|
| SiC-T-1200 | Tubular 1200 × 40 | 20 nm | 300–400 | 1200 mm | SUS316L |
| SiC-T-1000 | Tubular 1000 × 40 | 20 nm | 300–400 | 1000 mm | SUS316L |
| SiC-P-250 | Flat sheet 250 × 250 | 50 nm | 200–300 | 250 mm | SUS316L |
| SiC-M-19 | Multi-channel 19 channels | 20 nm | 300–500 | 1000 mm | SUS316L |
| SiC-M-37 | Multi-channel 37 channels | 20 nm | 400–600 | 1000 mm | SUS316L |
Where SiC changes the outcome
Mine water
Cui Jiagou, 2×75 m³/h: flotation ahead of 20 nm SiC, effluent 0.18 NTU, TSS removal 94%. The flotation does the coarse work so the membrane is not asked to store coal fines.
Seawater RO pre-treatment
Ningbo, 1160 m³/h flat-sheet SiC: cleaning cycle held at 20–25 days with effluent at 0.2 NTU, on a site where the polymeric train had been cleaned weekly.
Oily water
Produced water after hypergravity separation, to reach <10 mg/L oil for reinjection. The membrane is the last cut, not the first.
Inside the generator
The same 20 nm membrane is the gas-dispersion medium in ARFU flotation and NEO ozone units — a uniform pore gives a narrow bubble distribution.
Two things buyers get wrong
- Designing at catalogue flux. Use a fraction of the clean-water figure and let the fouling allowance be real. A membrane system sized at 600 LMH will be cleaned constantly; the same system designed at 200 LMH will not.
- Treating "20-year life" as maintenance-free. It describes the chemical stability of the material under specified pre-treatment and correct cleaning. Replacement intervals depend on feed quality and on whether the cleaning is actually done.
Membrane selection starts with the cleaning regime
Tell us what you need to clean off, and how often you can afford to stop. That decides the pore size, the element type and the pre-treatment — in that order.
Discuss a membrane duty → Fouling control