The XPORE inorganic tubular membrane is developed for handling difficult industrial streams with high viscosity and solid content, making it ideal for fermentation broths of amino acids, antibiotics and vitamins. The membrane is made from metallic and ceramic materials, which has a long shelf life and can withstand elevated temperatures and pressures, concentrated solvents and extreme PH conditions.
During the fermentation process, yeast cells convert malt sugars into ethanol, carbon dioxide and flavours. When fermentation is almost complete, most of the yeast cells settle to the bottom of the tank rendering some clarity to the supernatant liquid. To obtain a clear, tasteful and stable beer, the remaining yeast cells and other small solid particles are removed from the liquid via filtration.
The traditional filtration is done with Kieselguhr, a commonly used batch filtering media; also known as diatomaceous earth. Airborne dust from Keiselguhr poses a health risk. The handling and usage of Kieselguhr requires that the workers be protected against these airborne particulates. In addition, environmental laws classify spent Kieselguhr as hazardous waste and it is mandatory for proper disposal. This increases both disposal and environment costs.
The XPORE inorganic tubular membrane is found as a good filtration solution for beer clarification. Membrane thickness, pore sizes play a crucial role in retaining the clarity, flavour, nutrients and aromatic compounds in beer, as well as separating the hazy proteins to achieve the crystal clear liquid in the end product.
Schematic of a membrane circulation system
Summary The field tests were very comprehensive and rigorous and the test results met the brewery’s high operating standards and requirements. Each brew output was measured and matched against normal batch production and the results were spectacular - it met exacting requirements like removal of yeast cells, bacteria and colloidal; retention of nutrient, clarity, colour, and unique bitter aftertaste of beer.