Brewery DAF at 240 m³/h between UASB and MBBR
A large brewery water-reuse plant was losing anaerobic biomass from its UASB reactor into the downstream aerobic MBBR. A full-scale dissolved air flotation unit was installed between those two biological stages to intercept the carryover. The company and location are omitted here; the published hydraulic duty, solids loading, process position and acceptance criterion are retained.
A 240 m³/h DAF designed for solids concentrations above 3,000 mg/L consistently met a 30 NTU performance requirement while protecting the downstream MBBR. The DAF formed one barrier in a treatment train that recycled 1,500–2,000 m³/day of water.
Why the DAF was installed
The brewery generated approximately 3,000–4,000 m³/day of trade wastewater. Its existing reuse plant combined anaerobic treatment, aerobic treatment and reverse osmosis. The operational problem was not raw brewery solids at the headworks: it was biomass escaping from the UASB and entering the MBBR. That carryover increased solids loading and disrupted the aerobic stage.
This placement matters. The DAF acted as an interstage solids separator, not as a stand-alone COD treatment plant. Soluble brewery COD remained the duty of the biological reactors.
Published design and operating facts
| Item | Published value | What it means for design |
|---|---|---|
| Total brewery trade waste | 3,000–4,000 m³/day | The DAF peak rating is far higher than the daily average divided by 24; hydraulic peaks and recycle service have to be allowed for. |
| DAF hydraulic capacity | 240 m³/h | Full-scale interstage separator, not a laboratory or temporary pilot. |
| Solids design basis | More than 3,000 mg/L | The source explicitly couples the hydraulic rating to a high suspended-solids duty. |
| DAF position | UASB → DAF → MBBR | The separator protects the aerobic biofilm stage from anaerobic biomass carryover. |
| Acceptance criterion | 30 NTU | The source reports that the installed DAF met this requirement; it does not publish a TSS conversion or removal percentage. |
| Water recycled by complete plant | 1,500–2,000 m³/day | This is a whole-train result after biological treatment and RO, not a DAF-only water-quality result. |
Treatment configuration
- UASB reactor: anaerobic conversion of soluble organic load and production of biogas.
- Full-scale DAF: capture of escaped anaerobic solids at up to 240 m³/h and above 3,000 mg/L solids.
- MBBR: aerobic polishing without the uncontrolled solids burden from the UASB.
- Downstream reuse barriers: additional treatment including reverse osmosis to produce non-product-contact process water.
What this case proves—and what it does not
The case is strong evidence for DAF as a compact separator after anaerobic brewery treatment, especially where granular sludge or biomass carryover threatens an aerobic stage. It also shows why flow alone is not enough for selection: the published unit was specified against both 240 m³/h and solids above 3,000 mg/L.
The source does not provide influent and effluent TSS, chemical doses, recycle pressure, air-to-solids ratio or sludge dry-solids concentration. Those values are therefore not estimated here. A comparable project still requires representative sampling, solids-flux calculations and flotation testing.
The engineering figures on this page were checked against a published full-scale installation record. Operator, supplier and location details are intentionally withheld. The reported results are a technical reference, not a site-specific performance warranty.