The effective water depth of shallow air flotation is 400~500mm. Hydraulic retention time in the pool (3~5min). The purification capacity is large, that is, the surface load is high. Shallow air flotation has a small footprint and light unit load. All prefabricated components are assembled and no operating room is required. The equipment can be installed overhead and can also be combined in multiple layers. The installation and maintenance costs are low and easy to clean. Shallow air flotation has a high degree of purification, and the suspended solids removal rate reaches more than 90%. It has an ingenious structure, the dissolved air efficiency is as high as 90%, and the volume is only one-fifth of the general dissolved air system.
The air flotation separation technology of shallow air flotation means that air and water are dissolved into the water to the maximum extent under certain pressure conditions, striving to be in a saturated state, and then the formed pressure-dissolved gas water is reduced through Released, a large number of micro-bubbles are generated, which fully contact the suspended floc in the water, causing the suspended floc in the water to adhere to the micro-bubbles and float to the water surface with the bubbles to form scum and scrape off the scum, thus purifying the water quality.
Shallow air flotation is an advanced rapid air flotation system. Based on the traditional air flotation theory, it also successfully uses the "shallow layer theory" and "zero speed" principles. Through careful design, it integrates condensation, air flotation and skimming. It integrates slag, sedimentation and mud scraping, and is an efficient equipment for water purification treatment.
The raw water of shallow air flotation flows into the central tube at the bottom of the pool after flocculation and mixing. The scum on the water surface is collected by a skimmer, and then discharged into the central sludge tank and the matching sludge device. The scum that sinks to the bottom of the pool is The sludge is collected by the scraper and discharged to the sludge discharge tank, and the clean water is collected and discharged by the central water collection mechanism. Good flocculated raw water refers to the raw water formed by adding the flocculating agent PAC or PAM (PAC is 400-1000mg/I, PAM is about 1/5 of PAC) to the raw water, and the effective flocculation reaction takes place in 10-15 minutes. The specific dosage, flocculation time, and flocculation effect must be determined experimentally.
The shallow air flotation device integrates condensation, air flotation, skimming, sedimentation, and mud scraping. It is cylindrical in shape, has a compact structure, and has a shallow pool. The main body of the device consists of five parts: pool body, rotating water distribution mechanism, dissolved air release mechanism, frame mechanism, water collection mechanism, etc. The water inlet, water outlet and scum discharge port are all concentrated in the central area of the pool body. The water distribution mechanism, water collection mechanism, dissolved air release mechanism and frame are closely connected together and rotate around the pool body.
In shallow air flotation, the concentrator drives a small sprocket through a reduction motor, so that the large sprocket drives the worm gear to rotate. The scraper arm and scraper rotate with the main shaft to scrape the sludge into the sludge pit in the center of the pool. The sludge is under hydrostatic pressure. It will be automatically discharged out of the pool through the mud discharge pipe at the bottom of the pool.
