Patent ID: 6979308

Claim:
A bioreactor, comprising: (a) a housing having an inner side comprising: a gas introduction means integral to the housing; and a gas expiration means integral to the housing; (b) a plurality of modules of hollow fibers, residing within the housing, each module comprising: (i) at least three coaxially arranged hollow fibers, each hollow fiber having an inner side and an outer side, including an innermost hollow fiber and an outermost hollow fiber; (ii) at least three compartments, comprising: a first compartment defined by an inner side of an innermost hollow fiber and at least two compartments defined by a respective annular space between adjacent fibers of the at least three coaxially arranged hollow fibers; and (c) an outermost compartment defined by a space within the inner side of the housing which is not occupied by the plurality of modules; in which at least one compartment is charged with a gaseous nutrient substantially free of non-gaseous fluids.