Flotation Machine | Shallow Flotation Machine | Horizontal Flow Flotation Machine

Working Principle The dissolved air system dissolves air into water to make dissolved air water. After pressure release, a large number of micro-bubbles form. These bubbles mix with the incoming wastewater in the flotation tank, attach to suspended particles and oil droplets, and rise to the surface as a scum layer. A scraper removes the scum into a collection trough, while clear water discharges from the bottom or side. The shallow type uses shallow-pool theory and rotating water distribution to shorten retention time and boost surface loading. The horizontal flow type uses a gentle horizontal flow and scraper system so bubbles and flocs contact fully before separation. Dissolved air pressure, recycle ratio, and release device performance all affect bubble quality, which in turn affects separation. Application Fields 1.Refinery wastewater: removing emulsified oil and suspended solids to reduce the load on downstream biological treatment. 2.Food processing wastewater: separating grease, protein, and suspended solids to cut COD load. 3.Tannery wastewater: removing leather scraps, grease, and suspended solids to improve biological influent. 4.Coking wastewater: pre-treating to remove oil and suspended solids and reduce toxic shock. FAQ Q1: What surface loading rate does a shallow flotation machine typically run at? A: Usually 5–10 m³/(m²·h), with some reaching around 12. Because the tank is shallow, retention time is only a few minutes, and separation happens quickly thanks to rotating water distribution and micro-bubbles. It fits large flow with low suspended solids and takes up much less space than conventional flotation. Q2: How is the recycle ratio set for a horizontal flow flotation machine? A: Typically 20%–30%, depending on suspended solids concentration and effluent requirements. Higher concentrations call for a larger recycle ratio, but energy use goes up too. Dissolved air pressure is usually kept at 0.3–0.5 MPa. Too high a pressure makes bubbles merge and grow, which hurts flotation performance. Q3: What size are the micro-bubbles produced by a flotation machine? A: Most bubbles released from dissolved air water are 20–50 μm. The smaller the bubble, the better the chance it collides with and attaches to suspended solids and oil droplets, which improves flotation. Too large and they break easily; too small and they rise too slowly. The dissolved air system and release device directly determine bubble quality.