Anaerobic Digesters

The Upflow Anaerobic Sludge Blanket (UASB) reactor is a highly efficient anaerobic digestion system widely used for wastewater treatment. Its compact design supports the growth of anaerobic bacteria in a concentrated sludge blanket, promoting efficient organic matter degradation and biogas production. 

Notably, UASB reactors require less physical space compared to other anaerobic systems, making them suitable for constrained environments. They also reduce energy consumption by eliminating the need for energy-intensive mixing equipment. 

Moreover, UASB reactors minimize excess sludge production, reducing associated costs and logistical challenges. They find application in various industries, including municipal wastewater treatment, agro-industrial processes, and food production, contributing significantly to sustainable waste management by converting organic waste into valuable biogas while treating wastewater effectively. 

A Buoyant Filter Bioreactor also referred to as a floating filter bioreactor or floating bed reactor, represents a specialized bioreactor employed in wastewater treatment. It distinguishes itself through the incorporation of buoyant filter media, effectively amalgamating attributes of both suspended growth and attached growth processes. 

Notably, the Buoyant Filter Bioreactor offers several distinct advantages. Firstly, it boasts a compact design, resulting in a smaller physical footprint in comparison to alternative wastewater treatment systems. This attribute proves particularly advantageous in scenarios involving intricate wastewater treatment, especially when the chemical oxygen demand (COD) exists in suspended form and there is a notable presence of oils and grease. 

A back-flush UASB (Upflow Anaerobic Sludge Blanket) reactor is an upgraded version of the conventional UASB model, designed to improve performance. Similar to its conventional counterpart, this reactor operates under anaerobic conditions, facilitating the digestion of organic matter and biogas production. However, for complex wastewaters such as slaughterhouse, fish processing effluents, palm oil effluents etc, oil and other floating COD poses an issue – washout of sludge or poor treatment efficiency if the oils and floatable COD is not removed prior to the anaerobic digester, potentially diminishing its efficiency. 

To address this issue, the back-flush UASB reactor incorporates a periodic back-flushing mechanism. This process involves temporarily reversing the flow direction within the reactor, which dislodges and removes the accumulated solids. The mobilized solids, along with the back-flush medium (water or gas), are then reintroduced into the reactor. 

The advantages of incorporating a back-flush mechanism into the UASB reactor design are significant. It helps maintain the reactor's hydraulic functionality and treatment efficiency by preventing the buildup of solid matter, reducing the risk of obstructions, and enhancing process stability. Moreover, the back-flushing process optimizes biogas production by eliminating hindrances to gas transfer and microbial activity. Additionally, it reduces reactor downtime and improving overall operational efficiency. 

The conversion of an anaerobic reactor into a back-flush UASB (Upflow Anaerobic Sludge Blanket) reactor with iActiveSettler technology enhances its performance. iActiveSettler improves solids separation and retention in anaerobic reactors. 

The process begins with assessing the existing reactor's performance, hydraulic features, and limitations. If suitable, iActiveSettler is integrated into the reactor, typically as a custom settler module. This addition enables intermittent purging of settled solids, reducing biomass buildup and improving reactor performance. 

The combination of iActiveSettler and back-flush capability offers various benefits, such as enhanced treatment efficiency, increased biogas production, and reduced maintenance needs, improving overall operation.