How ContourGlobal Maritsa East 3 TPP oversees the efficient use of water resources and wastewater treatment during electricity generation

Water accounts for more than 70% of the Earth’s surface and is home to millions of species, from the smallest to the largest. People’s very existence depends on it. Wars have been fought over water resources and still are. Water is the main requirement for life on Earth and one of the most valuable resources.

Only 3% of it is ‘fresh’ water – a source of health, vitality and energy. This limited resource has been threatened in the last century – surface and groundwater are subjected to various wastes, a byproduct of human activity. This problem affects ecosystems and directly affects human health and quality of life. As part of water conservation efforts, much stricter regulations and ordinances have been introduced in recent decades. And to draw attention to the protection of water resources, in 1992 the UN began to mark March 22 as World Water Day. These efforts are bearing fruit and we are witnessing more and more examples of how industrial companies manage to minimize their footprint.

Such a positive example in Bulgaria is ContourGlobal Maritsa East 3 TPP – one of the largest power plants in the Maritsa East complex, producer of more than 10% of electricity in the country. The efficient use of water resources was set in the design of the power plant in the late 70’s of the last century with the introduction of a recirculation condensate cooling system at the turbines end. The large-scale modernization of the power plant, which began 20 years ago, also included facilities for water flow management and wastewater treatment.

At that time we made serious changes in the control of water balance – we introduced innovative microprocessor control, built a treatment plant for industrial wastewater and a separate one for domestic waste water. We installed oil-water separators and precipitators. We built and put in operation facilities that were seen for the first time in Bulgaria and we were very pleased to welcome students and lecturers from different schools.

Angel Komarev, Environment Manager, ContourGlobal Maritsa East 3 TPP.

In addition to treatment, significant investments have been made in the efficient use of fresh water and the reducing the amount of wastewater. Two new fresh water pipelines have been built for the needs of the power plant. An integrated water management system has been introduced with all the necessary devices for process control and management. A buffer tank with a capacity of 30000 m3 was built for the ash and slag removal cycle; it helps with water use during peak operation of the power plant and thus drastically reduces the use of fresh water at such times.

‘We managed to solve the problem of water losses, which previously reached 50%. For us, this was totally unacceptable wasting of valuable natural resources. Thanks to the improvements we reached almost 2 times lower fresh water consumption’, said Eng. Komarev.

One of the latest achievements of ContourGlobal Maritsa East 3 TPP is the project implemented in 2014 to return the wash water from the self-cleaning filters of the condensers back to the circulation-cooling cycle. ‘The results of this modernization are truly remarkable – the reused water equals the volume of 15 Olympic-size swimming pools and as a result we have reduced fresh water abstraction and wastewater discharge, said Angel Komarev.

Another important improvement of the power plant is the building of a self-cleaning water flushing filter. This provides additional mechanical purification of already used water and its reuse for service needs. ‘Now we completely avoid the use of fresh water’, explains Eng. Komarev. ‘Our efforts have led to positive results, but this is not the end of the process. We have serious experience, highly professional staff and we continue to work to improve water management.’

In the last two years, ContourGlobal Maritsa East 3 TPP has been operating at maximum load, and the generated energy would cover the average needs of over one million Bulgarian households. So far, more than BGN 1.45 billion have been invested in modernization, environmental improvements, safety and reliable operation of the power plant, making it the first lignite-fired thermal power plant in Southeast Europe to operate in full compliance with the highest European environmental and occupational safety standards.