Water, Sewage & Effluent November-December 2017 | Page 13

The wastewater pond system will also prevent environmental hazards, and a cut-off drain has been installed to prevent groundwater contamination. “Although there is no requirement to design and construct the milking parlour in accordance with quality standards SANS 204 and SANS 10400,” he points out, “the principles of energy-efficient design will be applied to all building services – in case of changes to future compliance requirements.”  Extensive mechanical and electrical services are required to ensure a fully functional dairy, as a large range of equipment including compressors, a vacuum pump, heat exchangers and heat pumps, hot water storage, and chillers are required. Various pumps outside the building have been installed to ensure water – domestic, chilled, and recycled – is available across the facility. SRK appointed CA Water Sewage & Effluent November/December 2017 11 contributor this activity is normally stored in a large earth pond and allowed to evaporate. However, our ground- breaking innovation allows the dairy to save 30 000 litres of water a day by re-using effluent to clean the external concrete areas around the dairy.” This, says Meiring, is achieved by piping wastewater from the dairy’s washing operations to a series of primary and secondary ponds. These ponds function anaerobically to allow the settlement and digestion of organic material while clear effluent (without solids) will overflow to the wash water pond for reuse. “An integrated pipe network allows solids to settle before the water flows to the wash water pond,” he says. “The system will probably only need maintenance after about 15 years, after which a partial de-commissioning will be required to undertake maintenance.” new dairy reaches full production, its output will expand to over six million litres of milk a year, which will be sold to dairy giant Parmalat. Contracted to manage the construction of the new project, SRK Consulting (South Africa) is ensuring that it is not just technically top-class but also environmentally responsible. Health, hygiene, and cleanliness are clearly items at the top of any dairy’s list of success factors, and plenty of water is usually necessary to keep such a facility spotless. “The dairy uses about 50m 3 of water daily from a nearby borehole to clean milking equipment and the concrete hardstand,” says Marinus Meiring, associate partner at SRK Consulting. According to Meiring, various water reticulation systems are in place enabling the dairy to be cleaned twice a day – after each milking cycle. “Wastewater from Sludge and wash water ponds prior to commissioning. Note rehabilitated slopes and embankments.