TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: In the system: there is one process utility disposed downstream of the pretreating device, the housing has one outlet, and there is one conduit for providing uninterrupted fluid communication between the outlet of the housing and the process utility for conducting the vapor and liquid phases directly into the process utility; or there is one process utility disposed downstream of the pretreating device, the housing has first and second outlets, and there are two conduits for providing uninterrupted fluid communication between the outlets of the housing and the process utility, where the conduits are first conduit for providing uninterrupted fluid communication between the first outlet of the housing and the process utility for conducting the liquid phases directly into the process utility, and second conduit for providing uninterrupted fluid communication between the second outlet of the housing and the process utility for conducting the vapor phases directly into the process utility; or there are first and second process utilities disposed downstream of the pretreating device, the housing has the first and second outlets, and the two conduits. In the combined tangential shear homogenizing and flashing apparatus (A1): the housing has one effluent outlet through which the vapor and liquid phases are able to pass together to a downstream utility; and the housing has first and second separated effluent outlets through which the vapor and liquid phases are respectively able to pass separately to downstream utilities.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The method further comprises: conducting the vapor and liquid phases directly to utility, where the vapor and liquid phases are each conducted separately to a utility, or the vapor and liquid phases are conducted together to a utility; monitoring the at least one of pressure, temperature, particle size and/or composition (e.g. nature) parameter of the pretreated influent biomass upstream of the mixing zone, varying the axial dimension of the mixing zone in accordance with the monitored parameter(s) and varying the rotational speed of the rotor in accordance with the monitored parameter(s); and sensing the pressure of the mass of material upstream of the mixing zone, varying the axial dimension of the mixing zone in accordance with the pressure of the mass of material, and varying the rotational speed of the rotor in accordance with the pressure of the mass of material.