Anaerobic tower

► Function of the Anaerobic Tower

Anaerobic biological treatment of wastewater is an important technology in environmental engineering and energy engineering, and is one of the powerful methods for treating organic wastewater. In the past, it was mainly used for the treatment of sludge, organic waste, and some high-concentration organic wastewater in municipal sewage treatment plants. This is the use of biological methods to treat wastewater.

► Anaerobic Tower Working Principle

(1) The production wastewater, after adjusting the PH and temperature, first enters the mixing area at the bottom of the reactor, and is fully mixed with the internal circulation sludge and water mixture from the tap water downcomer, then enters the granular sludge expansion bed area for COD biodegradation. The COD volumetric load here is very high, and most of the influent COD is degraded here, producing a large amount of biogas.

(2) Biogas is collected by a primary three-phase separator. Due to the stripping effect produced by the expansion work done on the liquid during the formation of biogas bubbles, the mixture of biogas, sludge, and water rises along the biogas lift pipe to the enterprise separator at the top of the reactor, where the biogas is separated from the sludge and water and exported to the treatment system.

(3) The sludge and water mixture flows along the sludge and water downcomer into the mixing area at the bottom of the reactor, and after being fully mixed with the influent, it enters the sludge expansion bed area, forming the so-called internal circulation. According to different influent COD loads and different reactor structures, the internal circulation flow rate can reach 0.5-5 times the influent volume. After treatment by the expansion bed, part of the wastewater participates in the internal circulation, while the rest of the wastewater passes through the primary three-phase separator and enters the granular sludge bed area of the fine treatment area for residual COD degradation and biogas production, improving and ensuring the effluent water quality. Since most of the COD has been degraded, the COD load in the fine treatment area is low, and the yield is also small. The biogas produced here is collected by a secondary three-phase separator, enters the gas-liquid separator through the gas collection pipe, and is exported to the treatment system. After treatment in the fine treatment area, the wastewater is acted upon by the secondary three-phase separator, the supernatant is discharged from the effluent area, and the granular sludge returns to the sludge bed in the fine treatment area.

► Anaerobic Tower Working Principle

It makes full use of anaerobic granular sludge technology. By using external circulation to provide sufficient upward flow velocity for the reactor, it maintains the expansion of the granular sludge bed and the mixing inside the reactor, improving the treatment efficiency of the reactor.