High-Quality Beer

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Bredel 25 Peristaltic pump distributed by Watson-Marlow, with twin-bearing hub ensuring sturdiness and reliability

With correct pumps, Watson-Marlow satisfies the thirst for quality at one of the largest breweries worldwide.

When conventional piston pumps threatened quality at one of Europe’s most productive breweries, the problem was tacked by the Watson-Marlow Pumps Group, only authorised distributor of Bredel products. The solution was a Bredel 25 peristaltic pump with direct coupling; the measure was such a success that the Anheuser-Busch InBev brewery in Magor, Monmouthshire (South Wales) has since installed six of these pumps for similar applications. “Brand image and customer satisfaction cannot be quantified”, says Paul Evans, product manager at the Welsh brewery. But, of course, Bredel pumps enabled us to guarantee the satisfaction of customers and consumers of InBev products”. Anheuser-Busch Inbev is one of the world’s top consumer product companies, with a business activity based in more than 30 countries worldwide and more than 36 billion USD revenue. With a workforce of over 120,000 persons, the company produces four of the ten biggest selling beer brands of the world.

Dosing of kieselguhr
Kieselguhr, a sedimentary mineral in slurry form is used by all brewers worldwide as a necessary part of the filtration process. In this process, pumps are used for the dosing of kieselguhr that creates an important and necessary layer on the filter. Piston pumps used until now were providing the opportunity for dissolved oxygen (DO) to infiltrate the beer during the dosing process. Even the slightest traces of DO in beer can change its flavour, making it taste stale”, explains Paul Evans, “and the consequences on image and product sale may prove to be catastrophic”.

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Bredel 25 pump, installed at the Welsh Anheuser-Busch InBev brewery, one of the world’s top breweries

Control of dissolved oxygen
The reputation of Anheuser-Busch InBev is really worth protecting. In fact, several of the brands that are most popular with consumers, as Stella Artois and Boddington, are produced at the Magor site, together with Brahma, Bass and Budweiser. Even for this reason, “it is very important to maintain a very low DO level in beer”, points out Evans. “Our aim is to maintain rigorous dissolved oxygen levels of less than 10 ppb (parts per billion) over the entire process. Unfortunately the stainless steel non-return valves on the discharge side of the piston pumps suffer the corrosive nature of kieselguhr. As a result, pumps must be replaced or need frequent maintenance interventions, which inevitably expose the beer to atmosphere”. The brewery decided to test Bredel 25 pumps distributed by Watson-Marlow on three filter mains. The test was a success, since “there is no way to introduce oxygen to the process with the peristaltic process”, explains Evans. “Anyway, the facts prove it, and we decided to introduce a Bredel 25 pump on our filter mains.

Peristaltic pumps
Peristaltic pumps do not feature valves nor gears. The pumped fluid comes in contact with the internal wall of the pipe, preventing any contamination. InBev tested the pump with volatile colouring agents, and the positive results brought to the introduction of two additional pumps for the filter mains. The pumps are connected through an inverter to the PLC via Scada interface, for continuous adjustment of the speed according to the needs. “We think it is very useful to be able to monitor the actual time of use of the pump, in order to replace the pipe every 2000 working hours, as suggested by Watson-Marlow as part of the scheduled maintenance”, points out Evans. The Bredel 25 pump with its twin-bearing hub ensuring its sturdiness, combines the advantages of bare-shaft construction with those of a close-coupled pump. The pump bearings absorb the forces occurring in the pump, placing no load on the gerbox bearings and on the base plates, with a view to cut maintenance costs and installation time.