Chemical Technology May 2015

RENEWABLES

Another area of highwater use is in humanwaste disposal. Toilets themselves can use up to 15 litres of water with every flush, and processing of the sewage uses considerably more. GE is presently developing large mobile water-treatment plants for use in the Middle East which can return waste- water for human consumption or, in the most arid regions, desalination versions can produce large quantities of fresh water from the ocean. The Bill andMelinda Gates Foundation “Reinvent the toilet challenge” is a project aimed at developing new treatment processes and more efficient ‘loos’. A recent demonstration of the system even used the biomass recovered from the process to power the treatment plant. Efficiency, in other words, doesn’t just cater to environmen- tal concerns, it is also very good for business effectiveness and profitability. Genetic modification is also not only about staple crops. Ribena, a popular British drink made from blackcurrants, is threatened by the mild winters and warm summers in the UK. Blackcurrants have been grown in the UK since the 1800s, but, in some areas of the country such as Kent and Somerset, two varieties of blackcurrants – Baldwin and Ben Lomond – are suffering from increasingly poor yields. GSK is working with The Scottish Crop Research Institute’s

planted along river banks to stabilise the soil and prevent run- off of pesticides and pollutants. A water pump now irrigates closer to the ground and at lower pressure. The result is a saving of over 1 700 cubic metres of water annually. Coca Cola and Pepsi are both working to reduce their water use in beverage manufacturing. By comparison, Coca Cola uses only 1,3 litres of water per litre of beverage, but their volumes are significant. They are promising to reduce that to 1,2 litres per litre. Agriculture, though, is where water savings really need to bemade. Research and product development has focused on two dimensions: more focused water use and efficiency in its management and distribution; and in genetically modifying crops to require less water in the first place. John Deere has a range of precision irrigation systems. These, also known as drip irrigation, ensure that water is not randomly sprayed but delivered directly to plant roots. This minimises evaporation and over-watering, the two main culprits in inefficiency. Drip irrigation is mainly used by large- scale farmers because of the need for electronic control systems, pumps, valves and the various accoutrements of a processing plant. John Deere acquired Roberts Irrigation, which focuses on much smaller scale agriculture, including greenhouses, and at much lower cost.

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Chemical Technology • May 2015