United Utilities, the UK’s largest listed water company, is the latest water utility to sign a contract with Israel’s Mapal Green Energy for wastewater treatment. United Utilities is now the third UK water provider to purchase Mapal’s bubble aeration water purification system for use in municipal and regional water supply systems.
The deal is set to supply Mapal-purified water to approximately 7 million northwest England homes. Mapal last year signed deals with Anglian Water and Thames Water, two large water suppliers in southern England. As a bonus, Mapal has been accepted as a member of British Water, the UK’s leading trade body.
In a Mapal system, water bubbles infused with air are used to clean water as part of aeration systems, removing pollutants and separating sludge from water. The treatment removes most solid waste and pollutants, allowing water providers to purify and recycle water quickly and efficiently. Mapal’s technology eliminates many problems that have stymied adoption of the more effective and less expensive bubble purification technology.
Water professionals consider bubbles one of the more effective ways of treating sewage and water suffering from industrial pollution. Bubble purification systems were unpopular because they are generally limited for use in smaller, man-made pools and lagoons.
In a bubble purification system, a machine pumps oxygen into wastewater to enhance aerobic digestion, a bacterial process occurring in the presence of oxygen, in which bacteria convert organic matter into carbon dioxide and then release it into the atmosphere.
Traditional aeration systems have limitations. In order to get the bubbles to all parts of the wastewater, water utilities have relied on mechanical aeration or jet aeration. The former involves large machines that make bubbles by agitating the water, while the latter relies on jets pushing air into the water. Both are expensive to run, requiring large amounts of energy to diffuse the air into the water. Jet aeration, while slightly cheaper, is suitable only for small concrete-lined pools or lagoons.
Mapal’s system solves all these problems, according to company CEO Ze’ev Fisher. His firm’s idea is to use floating aerators that “travel” across the surface of the water, diffusing oxygen throughout pools up to a depth of six meters. Unlike with floating mechanical diffusers, Mapal’s system has a series of tubes that extend into the water, requiring far less energy to push the oxygen into the lower depths of the water. The oxygen gets to all parts of the wastewater, ensuring that aerobic digestion can occur equally in all parts of the pool. Because the tubes can get to all parts of the wastewater, the system doesn’t need as much energy to push the oxygen out.
Citing statistics from its customers in the UK, Israel, Brazil, South Africa and India, water utilities save between 40 percent and 70% of the energy used with other diffusion systems and 80% of maintenance costs.
Energy efficiency is what closed them on buying Mapal’s system, said officials of United Utilities, which has tens of millions of customers. The new Mapal system is scheduled to replace their current fixed mechanical aerators. At the first stage, the company is set to replace 16 aerators with Mapal units, with plans to upgrade further in a gradual manner, until the majority of its hundreds of fixed aerators are replaced. “The system will provide a number of benefits in addition to attractive power savings and may provide a financially viable lower cost solution compared to traditional installations for small to medium sized surface aeration plants,” said Dale Walker, a senior engineering manager at United Utilities.
Those energy savings impressed British Water, which invited Mapal to join its exclusive club. British Water not only represents the interests of members to the government and regulators, but it is also a facilitator for the presentation and marketing of new technologies in the industry via its networks of manufacturers, consultants and contractors.
“Within several months we have signed three contracts with the biggest water companies in the UK. In addition to the current installation, Mapal has provided its technological solutions to Anglian Water, supplying around 6 million homes, and Thames Water supplying around 14 million customers in the London area,” said Fisher. “The last couple of installations have proven the technology beyond expectations, which is why we keep getting more requests from British water organizations and manufacturing enterprises interested in our system, to achieve significant savings of operation costs.”
Click below for a video demonstration of Mapal’s system: