Enhancing Water Quality in Beer Production

Product

SupaCarb BP

Client

Global Beer Producer

Application

Water Quality Improvement

Location

Australia

Value Added

Improved and Guaranteed Beer Quality

Sector

Food & Beverage

The Importance of Water Quality

Water has been quoted as 'the integrity and purity of beer'. The taste and appearance of a beer lives and dies by the quality of the ingredients used in the brew. As beer is approximately 90% water, its quality, or lack of it, can cause fundamental changes in its taste and aroma.

Municipal water is the most likely source of water for brewing. It undergoes rigorous treatment processes to ensure its safety for drinking. These processes often involve disinfection using chemicals such as chlorine to reach levels deemed safe for consumption. However, while these treatments make the water potable, they can react with the natural phenols present in the malt and hops during the brewing process. This reaction results in the generation of chlorophenols which can impart unwanted and unpalatable plastic like flavours and aromas on the beer.

The level of chemical treatment required can vary depending on the condition and length of distribution pipes as well as natural events such as flooding. For example, during floods, as water levels rise, additional contamination can enter the water source at reservoir or bore hole. Inevitably this leads to chlorine levels varying considerably over the year and seasons (wet/dry), providing significant challenges to the purification system in the brewery. Municipal water in the region of the brewery typically contained between 0.5-1.5ppm of chlorine.

Traditional carbon beds are often used to dechlorinate the water prior to being used in the brewing process. Here we discuss the successful implementation of cartridge filtration utilising carbon block technology.

New Installation showing housings containing SupaSpun BP downstream of UF modules

Background to Production Problems

The original brief for the project was to upgrade the existing MF (Microfiltration) modules with new chlorine resistant and more efficient UF (Ultrafiltration modules). However, the existing de-chlorination system used 3 large traditional granular activated carbon (GAC) beds housed in Glass Reinforced Plastic (GRP) vessels, installed prior to the MF stage as the membranes were not chlorine resistant. The opportunity was taken to also improve this stage.

This system had a number of problems associated with it:

Heavy microbial loading emanating from the carbon beds
The carbon beds had to be backwashed on a daily basis. This added to the customer's already 'at capacity' trade waste discharge allowances (liquid waste discharged to the sewer)
Frequent MF system backwashes due to carbon and microfouling on the modules
No CIP (Clean In Place) ability on the carbon due to GRP housing construction (this contributed to the microfouling)
Permanent scaffolding required around carbon vessels to allow operator access for carbon media changeouts.
The requirement for scaffolding also increased health and safety risks
Water routinely out of specification for microbial contamination

Upgrading from MF to UF

The first stage of the process upgrade was to change over the old MF modules to a new 'state of the art', chlorine resistant UF plant. The plant was designed and installed by Amazon Filters distribution partner in the area, BHF Technologies who specialise in F&B processing technologies. Benefits of the system include:

The ultrafiltration plant utilised advanced PVDF hollowfibre, manufactured using the TIPS process (Thermally Induced Phase Separation). This ensured chlorine tolerant modules. These also have high chemical compatibility to other commonly used cleaning chemicals
Routine programmed backflushes on the UF system, plus periodic CEB (Chemical Enhanced Backwash) ensured the UF modules remain free from microbiological contamination and do not foul prematurely

SupaCarb BP for dechlorination

The 3 GAC beds were replaced by SupaCarb BP carbon block cartridge filters. As the UF modules were chorine resistant the carbon stage was placed downstream of them. This configuration ensures excellent protection to the carbon stage, thus leaving the SupaCarb BP's to deal purely with reducing chlorine levels.

The SupaCarb BP is manufactured from a combination of both powdered and granular carbon providing excellent chlorine removal.

150 off 30" SupaCarb BP filter cartridges were installed across 6 stainless steel housings to cope with a total flowrate of 80m³/hr (see installation photo above).

The carbon stage was followed by 30 off 30" SupaPleat Plus particulate removal filter cartridges as a preventative measure should the carbon blocks be damaged due to out of trend process conditions. Damaged filters can result in carbon particles being released from the filter.

The Benefits

The UF system provides excellent pre-filtration to the SupaCarb BP cartridges (nominally 0.03um) meaning zero solids loading onto the carbon filters. This is typically problematic as the water has a high concentration of colloidal silica and organics which can prematurely block an unprotected filter within a few days
Due to the high efficiency of the UF modules the carbon cartridges last 6 months without differential pressure increase
The SupaCarb BP cartridges are replaced on a routine service change-out when the carbon is exhausted. Service life is exactly as calculated from the capacity stated on the datasheet. This allows accurate and optimised sizing of dechlorination systems
Zero backwash required for carbon filters as they were so well protected from colloidal particles and organic contamination
The production line and carbon filters are only heat sanitised at installation and have not needed additional treatment during the standard 6 month lifecycle.
For the first time in 10 years micro contamination is now always in specification at this brewery site.