Equipment Introduction
The horizontal flow dissolved air flotation (DAF) machine is a water treatment device that injects air into water. Air is dispersed into highly fine bubbles, which act as carriers to adhere to suspended particles in water, forming a three-phase mixture (air, water, and particles/oil) in the form of foam. The separation of solids from liquids is achieved by collecting this foam or scum layer. It effectively removes suspended solids, oils, and colloidal substances from wastewater, serving as a primary unit in preliminary wastewater treatment stages. Currently, it is widely applied in water supply, industrial wastewater, and municipal sewage treatment-including sectors such as petrochemicals, coal mining, paper-making, printing and dyeing, slaughtering, and brewing. Scum removal is performed by a scum scraper, with a COD removal rate of 10% to 50% and an SS removal rate exceeding 95%. This machine boasts advantages like low investment, compact footprint, high automation, and easy operation and management.
Working Principle
Raw water is fully mixed with chemicals via an agitation system before entering the contact tank. Meanwhile, air and water form dissolved air water in the pressure vessel (dissolved air tank). The dissolved air water is depressurized through a releaser and released into the untreated water in the contact tank.
The air dissolved in water is liberated as micro-bubbles (20–60μm in diameter), which adhere to suspended solids in the wastewater. This reduces the specific gravity of the solids below that of water, causing them to gradually rise to the surface and form scum. A scum scraper on the water surface scrapes the scum into a slag trough for discharge. Contaminants with a higher specific gravity than water settle into hoppers at the bottom of the tank. No mechanical sludge scraping equipment is required-each hopper is equipped with an independent sludge discharge pipe, enabling separate and non-interfering sludge removal.
Structural Composition
The DAF equipment mainly consists of a flotation tank, mixing and agitation system, pipelines, pressure dissolved air system, dissolved air water release system, overflow water outlet system, sludge discharge system, scum scraping system, electrical control system, and operating platform.
structural composition
