The best DAF unit for industrial wastewater is the one demonstrated to meet your outlet target across the agreed flow and influent range. Start with representative samples and both hydraulic and solids-loading calculations. A larger catalogue capacity, a claimed removal percentage or a low vessel price does not by itself identify the right system.
Define the duty before selecting a model
Record average and peak hourly flow, production hours, batch releases, cleaning chemicals, temperature, pH, TSS, oil and grease, total COD and soluble COD. Describe the sampling method and production conditions. Establish whether DAF is pretreatment before biological treatment, final solids separation or another duty. Use the actual downstream or permit requirement as the outlet target.
The existing DAF product page provides a starting model range. Ask the supplier to confirm the selected unit's loading limits, layout and operating requirements against your enquiry rather than treating that range as a performance guarantee.
Check the loads with a transparent calculation
Illustrative assumptions, not measured project data: feed flow 20 m³/h and inlet TSS 600 mg/L. Inlet TSS load = 20 × 600 ÷ 1,000 = 12 kg/h. If the agreed trial outlet is 60 mg/L at the same flow, outlet TSS is 1.2 kg/h and captured feed TSS is 10.8 kg/h. Chemical precipitation can add solids, so this is not the final sludge production estimate.
Hydraulic loading is flow divided by the area defined for the equipment design. Ask whether that flow includes recycle and whether the area is plan area or effective separation area. Do not interchange a supplier's hydraulic loading and solids loading figures. P-TEC's published capacity caveat illustrates why a hydraulic model rating needs a solids-load check.
| Item | Required supplier response | Acceptance evidence |
|---|---|---|
| Capacity | Feed/peak/recycle flows, area and solids-loading basis | Signed calculation and operating envelope |
| Chemistry | pH, chemical product, dose basis and trial result | Representative jar and flotation testing |
| Mechanical scope | Vessel material, air/recycle system, pumps, skimmer and controls | Drawings and equipment schedule |
| Cost | Itemised installed scope and recurring consumption | Dated quotation and reproducible calculation |
| Performance | Outlet concentration/load, operating conditions and exclusions | Agreed site test and remedy for failure |
Use trials to choose the process, not just the vessel
Test expected production conditions, including difficult batches. Compare pH and chemical conditioning, observe flotation and settling behaviour, and measure the outlet pollutants that matter. Do not infer dissolved-pollutant removal from a clear-looking sample. Record the proposed dosing system duty and sludge handling requirement. If residual biodegradable pollution needs further treatment, evaluate the downstream process, such as an MBR, separately.
Compare total scope and verify it on site
Request equipment, civil works, electrical installation, freight, commissioning, training and spares as separate cost lines. Calculate power from running load and hours, chemicals from trial dose and product price, and sludge cost from estimated wet mass and a local disposal quote. This page provides no verified market-price range or project payback.
Before ordering, agree inlet and outlet sampling points, laboratory methods, test duration, expected production range and responsibility for a failed test. Record actual throughput, outlet concentrations, chemical consumption, electricity and sludge during commissioning. Accept the equipment against the complete agreed duty, not a single favourable sample.
Selection questions
Should I choose the highest-flow model?
Not automatically. Check peak handling, solids loading, controllability at low flow, maintenance access and the tested separation duty.
Can a trial establish a fixed chemical dose forever?
No. Keep the tested range and operating conditions, and provide for adjustment as wastewater changes.
Does high TSS removal mean final discharge compliance?
No. Check all applicable outlet parameters and any downstream treatment required.
