Pilot plant feasibility/case study on recovery and re-use of spent cleaning solutions
The Cleaner Greener Production Programme project undertaken by FDT involved using membrane technology to recover and reuse spent caustic Clean-In-Place (CIP) solutions at the Diageo Brewery in Dundalk. A pilot plant was designed and constructed for the purpose of carrying out membrane trials. Koch nanofiltration membranes were selected, and the trials entailed running batches of spent caustic solution through the membranes in order to remove contaminants and recover caustic for reuse.
The findings from the trials indicate that caustic solution may be successfully filtered through both tubular and spiral membranes. A feasibility study on the construction of a production-scale membrane filtration plant at the Diageo Brewery was carried out. Overall, this membrane technology has great potential for replication in the brewing industry as well as a number of other industries. The payback period on such a plant would be 3.4 years.
In addition to spent caustic, FDT also carried out successful membrane trials on weak wort and trub (two by-products of the brewing process). Weak wort and trub were filtered to produce Clean-In-Place rinsewater (permeate). This permeate may be recovered at 65ºC, which results in reduced energy usage as well as reduced water heating costs. The material that remains after filtration has been completed (i.e. retentate), may have a number of possible uses in the alcohol distillation process. It may also be used as animal feed.
For further details, see the FDT PDF.
