Manchester brewery cleans up on water savings

Manchester, UK -- Joseph Holt, one of Manchester’s most famous private brewers has achieved 30% reductions in water usage for regular Cleaning in Place (CIP) of its cylindro-conical fermentation and conditioning tanks following its installation of two dual-purpose vessels equipped with Alfa Laval Toftejorg rotary jet heads.

Known for its traditional ales and mild, Joseph Holt has more recently added two own-brand lagers -- Crystal and Diamond -- to capitalise on the growing trend to lager-drinking in the UK. As sales of these premium brands have grown, so has the need for additional capacity for fermentation and conditioning.

Two 600-barrel Moeschle vesels were installed to meet this need, providing between them 1000 hectolitres of additional tank capacity. One of the tanks is used to ferment lager for seven days before it is transferred to the other, or to smaller vessels, where it is conditioned for three weeks.

Both tanks are 3.5 metres in diameter, and according to Keith Sneard, Joseph Holt’s head brewer, this made the tanks too big to clean using fixed spray ball technology. “ At that size, we didin’t feel there would have been sufficient force from a spray ball to clean them effectively”

Tank makers Moeschle recommended a rotary jet head cleaning system and Sheard had previous experience of using Alfa Laval Toftejorg equipment in other parts of the Joseph Holt brewery. Consequently, the brewer opted for rotary jet heads from the start, installing Toftejorg TJ20G heads with 4 x 5.5 mm diameter nozzles. The new tanks were installed to supplement eight existing cylindrical conical tanks, originally equipped with fixed spray balls, used to ferment, condition and store the lagers and a new smooth beer.

Folowign the installation, Joseph Holt also opted to replace the sprayballs in the eight smaller vessels with Toftejorgs and installed a 14 kw variable speed pump to meet the different flow demands of the rotary jet head machines and the traditional spray balls.

Before commissioning the new vessels, close inspection revealed a light proteinaceous deposit had built up over time, despite regular CIP using the spray balls. Once they had been operating the new cleaning system for a number of months, the vessels’ interiors were re-inspected and, said Sheard, were “ pin bright and like new”.

Each vessel undergoes a 40-minute CIP cycle consisting of a pre-rinse with cold water, a 2% caustic phase and post-rinse with dilute peracetic acid which stays on the internal walls of the tank as a terminal sanitiser.

In contrast to spray balls, which operate at high speeds and clean by deluging the internal walls of a tank, the Toftejorg rotary spray heads are gear-driven, operate at low speeds and clean by impacting over a 360-degree indexed zone within a defined timescale. Pressure of the cleaning fluid itself provides the motive force, driving the nozzles around both horizontal and vertical axes.

The first cycle lays down a coarse pattern which is then intensified by the following seven cycles. Cleaning is so effective that the rotary gear heads are certified to EHEDG guidelines.

Once the brewery began to measure water usage it found that the new rotary spray heads were miserly in their consumption. “ Although we haven’t taken formal measurements, “ said Sheard, “ it is fairly obvious just by looking at our disposal costs that our use of water in that area had been reduced by around 30%. In this day and age, that is a significant benefit.”

Sales of both Crystal, which is a 3.8 abv (alchohol by volume) beer, and Diamond (5.0 abv) are increasing throughout Joseph Holt’s estate of 125 tied houses in and around the Manchester area. In 2005 the quality of one of the two lagers was acknowledged when it was runner up in a major international beer competition.