The Anaerobic Contact (AC) reactor was one of the first reactor types to be used for anaerobic wastewater treatment. BIOTIM® AC is WATERLEAU's version of this technology. 

It is a simple concept, mainly consisting of a completely mixed reactor followed by a conventional sludge settler or a parallel plate sludge separator. Inside the methane reactor the active anaerobic sludge is kept in suspension by mechanical mixing. The settled sludge is continuously recycled from the sludge settler to the reactor. More recently, ultrafiltration has been used as an alternative for biomass separation.

Although the anaerobic contact process does not allow high organic loading rates (preferably less than 5 kg COD/m³.d), this concept is still used. Among other reasons are the great simplicity and the stable operation at varying conditions. When the wastewater characteristics are not all that favourable for anaerobic treatment (high ammonia concentration, high Ca2+ content,...), the AC pro cess remains a good alternative.         

Applications

COD < 5 kg/m³   

Advantages

All advantages of anaerobic treatment

Simple

Stable operation

Suited for wastewater with characteristics unfavourable to other anaerobic treatment.