Water & Wastewater Treatment

INDUSTRIAL TREATMENT 31 March 2014 Water & Wastewater Treatment wwtonline.co.uk A major wastewater treatment system expansion and upgrade project has been completed at the Otter Brewery in Devon. Industrial specialist, Micromac Filtration has designed, manufactured and installed a sequencing batch reactor (SBR), which provides biological wastewater treatment for the brewery to such a high degree that it can be safely discharged to the ecosystem surrounding the brewery. After extensive evaluation of various suppliers, who offered a range of different technologies including submerged aerated filter systems, the brewery opted for Micromac's SBR. The company says this approach facilitated the integration of existing treatment equipment into a cost-effective, low visual impact and extremely reliable wastewater treatment system. Otter was also able to receive a significant Regional Development Fund grant towards the cost with assistance from SDL and Micromac. Currently, the brewery makes 20,000 brewer's barrels of beer per annum and every pint of beer made requires 1.4l (2.5 pints) of water to be used in the production process. The brewery is fed by its own stream and thanks to Micromac's advanced wastewater treatment system it can return over 80% percent of the wastewater direct into the watercourse at the brewery. Using Micromac's SBR system, wastewater is collected in a sump and screened. Then a batch of prepared wastewater is pumped to the reactor tank where it is aerated. This has the effect of mixing activated sludge already within the tank with the new wastewater and commencing the treatment of the whole. The aeration causes the biological oxygen demand (BOD) components to be converted to sludge and the ammonia to nitrates. The mixed liquor suspended solids (MLSS) are measured, and the system is configured to automatically maintain the optimum level for the processing of the wastewater. After a pre-set time, aeration ceases and the sludge is allowed to settle. During this phase, the nitrates are converted to nitrogen. After settlement is completed, surplus sludge is pumped from the reactor for disposal. The treated wastewater is measured for The ecologically sensitive site of a Devon brewery's treatment works meant installing an SBR system, says filtration specialist Micromac Filtration Otter Brewery installs SBR treatment system Perspectives Consultant "Otter Brewery is the victim of its own success with significantly increased demand for their beer generating an increased amount of wastewater from the brewing process. We were able to identify savings to help Otter Brewery to improve their operating efficiencies, with the resulting wastewater requiring a more sophisticated solution than was onsite at present." John Looney, managing director, Sustainable Direction Client "Micromac's SBR unit has settled in well and ticks all our boxes. Ecologically sympathetic, futureproofs production growth and is aesthetically pleasing. Long live those bugs and long may we continue to deal with our own wastewater." Patrick McCaig, sales director, Otter Brewery Contractor "Otter Brewery is a real Devonian success story and our work here will help the company to continue to evolve and grow. The batch reactor is an ultra-reliable, cost-effective and low maintenance solution that will protect the brewery and the environment in which it operates for many years to come." Richard Milton, managing director, Micromac Filtration Effluent from the Otter Brewery, which sits in an area of outstanding natural beauty and special scientific interest, is discharged to a natural wetland suspended solids, ammonia, pH, et cetera. If these are within pre-set levels the wastewater is discharged. If the levels are outside the preset limits, the wastewater remains in the reactor for reprocessing. Wastewater treated to the acceptable levels is passed to an outfall station for discharge. The outfall station is fitted with a flow meter to measure the volume and flow rate of the discharge. nnn

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