His expertise in the field eventually led to him setting up his own consultancy company which provides a service to companies seeking to utilise their water in the best possible way in order to save on capital and operating costs.
Mr Cremona’s “pet” idea, which is still in the pipeline but which will soon come to fruition, is recycling sewage by turning it into water of drinking-water quality. The objective is not to use the recycled water for drinking purposes (although it is technically possible to do so) but for all fresh water uses except drinking. It is interesting to note that of the 150 litres of water consumed every day per person in Malta, less than five litres are actually used for drinking or cooking purposes.
The process, he said, is available and affordable. It is significantly less expensive than the seawater desalination process Malta uses today and it also hits two birds with one stone – providing an alternative source of good quality water whilst treating waste (sewage).
In an interview with The Malta Independent, Mr Cremona talked about other projects he has in mind. Among these is the production of electricity from animal waste. In July 2000, Mr Cremona was part of a Maltese volunteer group that built a biogas plant in Kenya which turned agricultural waste into cooking gas. To date, the plant is still producing biogas for 90 hot meals a day from the dung of 16 cows.
“Malta cannot waste any of its resources. Up till now, we have always thrown our sewage into the sea but we can use the residue (sludge) from the sewage treatment process to produce electricity. This would also be a saving for the country and its citizens in electricity costs. It should be seen as a way to treat waste while at the same time producing energy,” he explained.
“The project makes economic and environmental sense. By treating the agricultural waste from farms and abattoirs through this process, we could easily save up to four per cent of our national electricity consumption. Tests that have been carried out so far have shown that a typical pig farm can provide enough gas to meet the farm’s needs and also give it the facility to sell just as much to the national electricity grid.”
He said that the problem of having untreated sewage will be more evident within the next two or three years when the sewage treatment plants have been built. These treatment plants will not be in a position to handle the concentrated slurry from farms and pre-treatment of this waste will become essential. The use of an anaerobic digestion process will treat the waste and also provide free energy. It is a win-win situation all round. An on-farm plant costs around Lm20,000 or Lm30,000 but the investors will get the return on their investment within seven or eight years – from electrical savings savings only.
Mr Cremona explained that excrement of any animal – including humans – and other biodegradable matter is the source of biogas. This gas is produced when animal waste or any other organic material digests in the absence of oxygen. The gas is composed of between 50 and 70 per cent methane, 30 to 40 per cent carbon dioxide and low amounts of hydrogen, nitrogen and hydrogen sulphide. Biogas is an odourless and colourless gas that burns with a clear blue flame.
To produce biogas for energy use, potentially-infectious animal manure and other biodegradable material (such as food residues) are mixed with water and stirred inside an airtight container called a digester. Bacteria continue the process of breaking down the manure that began in the animals’ digestive system.
The methane produced is then collected and stored and used for cooking, lighting and heating purposes, or to produce electricity. In addition to the gases produced, the fermentation of organic materials reduces them into a slurry with a high concentration of nutrients, making it especially effective and valuable as a non-infectious fertiliser.
Who is Marco Cremona?
Marco Cremona graduated in Mechanical Engineering from the University of Malta in 1992 and later worked as a projects engineer in water treatment with a local company. Two years later, he pursued his studies in water issues and obtained a Masters degree in Water Studies and Hydrology. From 1997 to 2002, he was in full time employment with a private company and was overseeing its water and environment-related projects. In March 2002, Mr Cremona took advantage of the start-up facility offered by IPSE and set up his own water consultancy company– Sustech Consulting – at the Kordin Business Incubation Centre (KBIC). Within a relatively short period of time, Sustech Consulting has established an impressive client base, including companies such as ST Microelectronics, the Water Services Corporation, Marsovin Ltd, Baxter Ltd and Actavis Ltd (formerly Pharmamed).