Sludge is where ETPs and STPs quietly fail — a full clarifier, rising outlet TSS, a tanker bill that never ends. We size and supply the right dewatering equipment for your sludge type and volume, and fix sludge lines that were never designed.
Every kilogram of BOD or coagulant produces sludge; if it is not removed at the rate it is produced, it accumulates in clarifiers, carries over as TSS, and eventually crashes the biology. Dewatering turns 1–3 % solids into a 15–30 % cake — cutting volume 8–15 times and the disposal cost with it. The right machine depends on sludge type (chemical, biological, oily), daily quantity, operator skill and space.
| Equipment | Best for | Cake dryness | Notes |
|---|---|---|---|
| Sludge dewatering bags | Small STPs/ETPs < 50 kg DS/d | 10–15 % | Lowest cost, manual |
| Gravity/picket thickener | All plants as first stage | 2–4 % | Halves downstream size |
| Filter press (plate & frame) | Chemical/inorganic sludge, batch | 25–40 % | Robust, labour for cake discharge |
| Screw press | Biological and mixed sludge, continuous | 15–25 % | Low power, low noise, small footprint |
| Belt filter press | Medium–large biological sludge | 15–22 % | Continuous, needs wash water |
| Decanter centrifuge | Large plants, oily/biological | 18–28 % | Compact, high power, skilled O&M |
It depends on sludge type and quantity: bags or a small filter press for very small plants, screw press for most biological sludges, filter press for chemical sludge, centrifuge for large flows. We compute kg DS/day from your plant and recommend.
Usually polymer dose or type, feed pressure ramp, or worn cloths. A day's trial with jar tests and cloth inspection fixes most cases.
Yes — a thickener, polymer system and press or screw press can be retrofitted into most ETPs/STPs; we design the pipework and layout.
Send plant type, capacity and current sludge handling — we reply with daily sludge estimate and equipment recommendation.