Water Journal : Water Journal May 2012
opinion regular features 40 MAY 2012 water Planning for Sustainable Use of Water in Abattoirs Guenter Hauber-Davison, Managing Director, Water Conservation Group I see that the grass is lush once more for most of eastern Australia, but effective and efficient water usage needs to remain a priority for the meat-processing industry. In a matter of three short years, much of Australia has swung from crippling drought to a weather pattern that has filled our dams and opened our spillways -- for many, for the first time in years. However, casting a glance to the west is a stark reminder of the realities of drought. Much of Western Australia is in drought condition, with many water storages at only 20 per cent capacity. Over the past 20 years, residential and commercial water users have become more aware of how water is used and, equally, how water is wasted, and have implemented many changes to improve water efficiency, such as greywater usage on our gardens, improvements to hose and fixture design, and rainwater harvesting. Our understanding of our weather patterns over both the short and long term has contributed significantly to our preparation for drier conditions. Weather patterns such as the Southern Oscillation, El Niño and La Niña, which greatly affect Australia's climate, have been thoroughly researched. The changes in our weather can now be forecast to show the likelihood of drought. However, exactly when drought will occur is not so easily determined. We have learnt a great deal and achieved significant changes in how we use our water, but what we need to do now is take stock of our successes and failures and learn from them, particularly while most of Australia has a respite from drought conditions. Now is the time to plan for the next drought, which is possibly only a few short years away. Climatologists have studied long-term weather and climate patterns and predicted that the severity of weather patterns such as El Niño and La Niña is likely to increase. Potentially, droughts will become more widespread and severe flood events more destructive, putting a great deal of pressure on our resources, such as water and the infrastructure used to support industry and communities. Water Usage in Meat Processing The food and beverage industry and, in particular, meat processing, is well known to be a significant user of water resources. Meat processors' primary function is to produce quality products that are safe for consumption. Compromising this through inappropriate cutbacks in water usage would be detrimental to public health and the meat-processing business. This is often used as an "excuse". Yet most plants still have a large scope to lower their water use and be more efficient. In addition, for many abattoirs water and energy costs are now a significant cost item. Slaughter and evisceration processes account for almost half the estimated 1,000 litres of water used per carcass. The remaining water usage for a typical plant* is principally for cleaning and plant operation, irrespective of throughput. Regulations regarding the use of non-potable water restrict usage to functions that do not have contact with products for consumption. However, there is significant scope to re-use water for yard cleaning, washing of animals, steam production and other activities such as irrigation. The source of re-usable water can originate from knife and equipment sterilisation, slaughter-floor sterilisation and hand washing. Treated final effluent can also be used within the plant or as irrigation on surrounding vegetation. The level of treatment undertaken will determine where effluent water can be used. In the event of the next El Niño, when rainfall diminishes, the less water that is taken into the plant the more successful the plant will be at surviving drought conditions. Many abattoirs have instigated water-saving measures such as trigger hoses, sensors and timers, and have educated staff on water usage, all of which have provided measurable changes in water consumption. Further actions that can be taken include dry-manure collection, suspended mesh flooring (not suitable for soft-footed livestock), partial processing, de-dagging and sensor-operated viscera and bleed tables. These changes to plant operation will minimise the intake of water into the plant and open opportunities for co-production -- for, example manure sales for composting. In the past, changes to water usage in abattoirs have had poor payback periods, as water prices were relatively inexpensive. However, water prices have now increased sharply and, with that, payback periods have reduced to the point where where they have become attractive. Analysis by the Water Group shows that as the price of water has increased by 40 per cent to 50 per cent over the last few years, payback periods have decreased from four to five years to less than two (Figure 1). Payback periods are a function of the cost of the water savings measure, how much water is used and the price set by the supplier. Therefore, accurate measurement of water usage needs to be undertaken in order to determine payback periods for a specific abattoir. Thus to effectively measure, monitor and make changes to the plant, an assessment of current water usage must be made. The use of meters in strategic points around the abattoir will not only show where the water is being used, but also where leakage or waste may be occurring. Acting on that data is the key to effective water management. Re-using water for non- critical tasks, putting in water-saving devices such as sensors Figure 1. As water prices continue to rise, payback periods for installing water-saving techniques decrease.
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