Academics from University College Cork have come up with a sustainablesolution to the ongoing problem of managing waste, reports Dick Ahlstrom
The EU is finally laying down the law. The Republic's overflowing waste mountain must go, but the problem is - how do we get rid of it? Researchers at University College Cork believe they have the solution: turning our rubbish into a reusable, safe and sustainable industry through composting.
The waste mountain is just one environmental problem being tackled by the UCC researchers, who are also trying to clean up water pollution caused by phosphates. In recent times there has been a significant increase in the levels of phosphate and other substances present in waste water discharged from treatment plants into Irish streams.
These chemicals promote the growth of algal blooms, which appear as a thin green scum on the water surface. The overgrowth of these blooms removes oxygen from the water, leading to fish kills. Research by UCC scientists aims to use biological organisms to help remove the phosphate.
The State is under pressure to clean up its environmental act. The EU is demanding a 65 per cent reduction in biodegradable waste at landfill sites. Scientists at UCC have developed methods to improve recycling of this through compost analysis while also tackling biological means of reducing chemical levels in our streams.
UCC microbiologist Dr Alan Dobson recently received a grant of €854,000 from the Department of Agriculture and Food and the Environmental Protection Agency to examine possible biological solutions to these difficult problems.
"Here at UCC we are using a process called biological phosphate removal (BPR)," explains Dr Dobson. "The method involves manipulating the growth process of the bacteria already present in the waste water treatment plant. It does not involve any form of genetic modification. It's an entirely natural process. We are looking at investigating microbial ecology (in the waste water treatment plant), as there is little known about it to date."
BPR was developed some years ago, but its effectiveness has not been tested here. The research involves trials of the BPR system but also a search for bacterial populations present in our water treatment plants that have the ability to support the BPR activity.
The phosphate removal process involves four stages, initially in the absence of oxygen and later with oxygen available. First, the incoming waste water, which contains both phosphate and a variety of carbon elements, is mixed with special BPR bacteria. The micro-organisms are particularly useful because they store phosphates in their cells in an oxygen-deprived environment.
Second, the bacteria use the stored phosphates by taking up the carbon from the water. The carbon provides the energy required to break down the phosphate store, releasing it for use by the bacteria.
At stage three, air is supplied to the system, bringing oxygen levels back up. This gives the cells energy to break down the carbon and reabsorb the phosphate.
This leads to the fourth step, in which the bacteria - now holding a bigger supply of phosphate - are physically removed from the system. The surrounding water will now have reduced levels of carbon and phosphate contamination.
UCC's research work is co- ordinated under the umbrella organisation BioTreat, a campus company, which performs trials on the system's feasibility for certain companies (go to www.ucc.ie/nfbc/Biotreat.htm).
Kerry Ingredients of Listowel has agreed to implement the BPR system on a pilot basis.
The project will start in July and run for three years. "We need to see how the system works over a complete season," says Dobson. "This technology has gained worldwide approval, but this is the first time Ireland has investigated biological solutions."
Dobson's research efforts also target the landfill problem. At present the Republic commits 90 per cent of waste to landfill, and composting could reduce this. The problem is that some of the compost produced at present contains potentially harmful chemicals because they were not removed at the start.
"Companies need to start segregating their waste into degradable and biodegradable," says Dobson. Land spread of compost is creating more of a problem today because of these residual chemicals, he adds.
Dobson's composting approach involves careful segregation and then testing to see if the biodegradable products are suitable for composting. In UCC, Dobson's team has developed techniques to test compost quality. These include methods of analysing the ingredients and agitation methods so that the composting potential is increased. The lab work will assess all physical and chemical characteristics such as particle size, visual contaminants and nutrient levels.
Any company that produces compost from waste will be obliged by forthcoming legislation to employ laboratories to test the quality, using these accredited methods. This testing is designed to develop the compost industry as a way of reducing the dumping of waste in landfills and, hopefully, will encourage an increase in recycling.
