Link
PROPOR TFF Hollow Fibre Cross Flow Filters
Single-Use TFF Operations
Overview
Scale-Up
Membrane Characteristics
PROPOR TFF filters can be readily scaled-up by maintaining a consistent hollow fibre path length and increasing the filtration area by increasing the number of fibres. In this way, the scale-up from approximately 100 cm2 to 5 m2 can be easily achieved.

Scale-up to even greater membrane areas has been achieved by increasing the path lengths although Parker domnick hunter recommends the longer path length is first tested in scale-down trails. 
Documents
TFF Automation
Scaling-Up Hollow Fibre Filters