*3.3. Brewery Wastewater*

Brewery wastewater is another high-strength wastewater that can be used in energy generation. It is generated in large volumes during beer production, whereby several processing steps, such as fermentation, saccharification, etc., are undertaken [59]. It has been studied that the MFCs can carry out brewery wastewater treatment [85,86]. A 20 L MFC was tested for one year [59], with the MFC being operated in different modes and/or phases, with phase A producing an external resistance (*Rext*) of 10 ohms and phase B producing *Rext* of 3.7 ohms, and up to *Rext* of 5.3 ohms in other phases, with the overall COD removal efficiency of up to 94.6% being achieved; albeit, the energy obtained seemed to be low, i.e., 1.61 mW/m<sup>2</sup> [59].
