The Continuous Stirred Tank Reactor (CSTR) was one of the first reactor types to be used for anaerobic wastewater treatment. BIOTIM® CSTR is WATERLEAU's version of this technology.

It is a simple concept, mainly consisting of a completely mixed reactor that can be equipped by a sludge separation tool, but generally without sludge recycle. Inside the methane reactor the active anaerobic sludge is kept in suspension by mechanical mixing. This type of reactor is typically used for very concentrated waters and or for waters that are rich in solids.

Schematic representation of a CSTR anaerobic reactor

This CSTR reactor type is used typically for digestion purposes. Generally this reactor is loaded at moderate organic loading rates. When the wastewater characteristics are not all that favourable for anaerobic treatment (high ammonia concentration, high Ca2+ content, high fats, ...), combined with high concentrated wastewaters, the CSTR process is an excellent alternative.

Applications

COD : 3 - 10 kg/m³

Advantages

all advantages of anaerobic treatment

simplicity

stable operation at varying conditions

suited for wastewaters with characteristics unfavourable to other anaerobic treatment (incl. fats)