GPS-X Technical Reference

169 Suspended Growth Models
ANAEROBIC MEMBRANE BIOREACTOR (MBR) (MANTIS2 ONLY)
Model Structure
The anaerobic MBR model in GPS-X combines the completely-mixed MBR (in simple
mode) with the gas transfer and headspace model of the anaerobic digester object. The
result is a completely mixed membrane bioreactor with a closed headspace and gas
production. Unlike the completely-mixed MBR, there is no modelling of the cake
formation on the membrane surface, backwashing of solids, or trans-membrane pressure
calculations.
The model assumes that the reactor is completely mixed with no aeration, and that filtrate
flow from the MBR is equal to the influent flow minus the pumped flow. It is assumed
that the filter is not limiting to the flow (i.e. that whatever flow is calculated can pass
through the filter unimpeded). The solids captured by the filter are retained in the
completely mixed bulk liquid.
The anaerobic MBR is only available in the Comprehensive (mantis2lib) library. The
anaerobic biological and chemical reactions are identical to those used in the anaerobic
digester and UASB models.
Model Input Parameters
The physical menu of the anaerobic MBR object is used to specify the dimensions of the
liquid tank and the headspace. In addition, the headspace total gas pressure, gas-liquid
transfer constant, and membrane solids capture are specified here as well, as shown in
Figure 6-17 below.
Figure 6-17 – Anaerobic MBR Physical Parameters Menu
GPS-X Technical Reference