NOVELTY - Producing (M1) dried bacterial mass additive involves: (A) adding aqueous waste stream comprising metabolizable components to a growth vessel containing bacterial culture; (B) allowing bacteria to grow to form a bacterial suspension; (C) separating portion of bacterial suspension from aqueous bulk liquid, to form a bacterial mass; (D) removing bacterial mass; (E) removing portion of aqueous bulk liquid, which is free of total suspended solids; (F) adjusting flow rate to provide mean bacterial cell retention time (MCRT) of less than or equal to 8 days; and (G) drying the removed bacterial mass.    USE - For producing a dried bacterial mass from the aqueous waste stream comprising dissolved and/or suspended metabolizable food or beverage byproducts from a food processing plant producing human or animal food; where the dried bacterial mass is useful as additive for animal feed or protein source for animals used for human consumption (claimed), as food additive for animal feed for animals such as cattle, horses, pet animals, chicken, or fish.    ADVANTAGE - The dried bacterial mass feed additive complies with the requirements of the American Association of Feed Control Officials Official Publication (2007). Controlling the mean waste residence time in conjunction with the MCRT provided improved protein levels. The process is carried out under aerobic conditions and provides feed having high protein content at lower cost than the conventional methods.    DETAILED DESCRIPTION - Producing (M1) dried bacterial mass as additive for animal feed involves:    (A) adding an aqueous waste stream comprising metabolizable components to a growth vessel containing at least one bacterial culture, at a first flow rate;    (B) allowing the bacteria to grow in the growth vessel by metabolizing at least a portion of metabolizable components of the aqueous waste stream, to form a bacterial suspension in an aqueous bulk liquid, where the aqueous bulk liquid is depleted of metabolizable components relative to the aqueous waste stream;    (C) separating a portion of bacterial suspension from the aqueous bulk liquid, to form a bacterial mass;    (D) removing the bacterial mass at a second flow rate;    (E) removing a portion of aqueous bulk liquid at a third flow rate, where the aqueous bulk liquid is free of total suspended solids;    (F) adjusting the second flow rate to provide mean bacterial cell retention time (MCRT) of the bacteria of less than or equal to 8 days; and    (G) drying the removed bacterial mass within a period where difference of mean waste residence time (MWRT) and (MCRT) (MWRT-MCRT) is less than or equal to 2 days.    INDEPENDENT CLAIMS are included for the following:    (1) waste water treatment (M2) involving: receiving a first signal, associated with a quantity of a first portion of a bacterial mass within a waste water treatment system, where the first portion of the bacterial mass contained within a first portion of an aqueous bulk liquid within the waste water treatment system; calculating a total cell mass of the bacterial mass within the waste water treatment system based on at least the first signal; receiving a second signal, associated with a quantity of a second portion of the bacterial mass, the second portion of the bacterial mass contained within a second portion of the aqueous bulk liquid, the second portion of the aqueous bulk liquid exiting the waste water treatment system at a flow rate; calculating (MCRT) of the bacterial mass within the waste water treatment system based on the total cell mass of the bacterial mass within the waste water treatment system and the second signal; and adjusting the flow rate of the second portion of the aqueous bulk liquid such that the MCRT of the bacterial mass within the waste water treatment system is within a predetermined range;    (2) business method (M3) involving: (a) calculating a processing cost associated with reducing a biochemical oxygen demand (BOD) level of an aqueous waste stream from an input BOD level to an output BOD level; (b) calculating a recovery value associated with a bacterial mass removed from the aqueous waste stream when the BOD level of the aqueous waste stream is reduced from the input BOD level to the output BOD level; and (c) adjusting automatically a contract price associated with reducing the BOD level of the aqueous waste stream based on at least the processing cost and the recovery value;    (3) business method (M4) involving: steps (a) and (b) of the method (M3); and (c) adjusting automatically a portion of the process based on at least the processing cost and the recovery value;    (4) a wastewater treatment unit (T1) comprising: a growth vessel; device for adding an aqueous waste stream comprising metabolizable components to the growth vessel; at least one bacterial culture in the growth vessel, which metabolizes at least a portion of the metabolizable components of the aqueous waste stream, thereby forming a bacterial suspension in an aqueous bulk liquid, where the aqueous bulk liquid is depleted of metabolizable components relative to the aqueous waste stream; device for aerating the bacterial suspension and aqueous bulk liquid in the growth vessel; device for separating a portion of the bacterial suspension from the aqueous bulk liquid, thereby forming a bacterial mass; device for removing the bacterial mass from the wastewater treatment unit; device for adjusting the rate at which the bacterial mass is removed to provide a MCRT of the bacteria in the wastewater treatment unit of no more than about 8 days; device for removing a portion of the aqueous bulk liquid from the wastewater treatment unit, where aqueous bulk liquid is free of total suspended solids; drier for drying the removed bacterial mass; and device for adjusting the period in which the removed bacterial mass is dried where MWRT-MCRT is less than or equal to 2 days; and    (5) a composition (C1) comprising a dried and deactivated bacterial mass comprising a mixture of bacteria, where the true protein content is at least 50%, and the dried bacterial mass is suitable for use as a feed for animals used for human consumption.