Coal-fired power plants require considerable quantities of water to operate and, as a result, generate large amounts of wastewater. Good management of the water and wastewater is becoming more important with the growing concern over the availability and quality of fresh water. Legislation applicable to the discharge of wastewater from coal-fired power plants in eight countries and the European Union is discussed. Most of the countries have set national quality standards to protect their surface, ground and coastal waters. Power plants discharging wastewater must not cause the receiving water body to exceed the stipulated limits. Some countries, such as Japan, South Korea and South Africa, have set maximum allowable limits on the amount of pollutants that can be discharged from industrial sources. On the other hand, India, Indonesia and the USA have national discharge limits specifically applicable to waste streams from coal-fired power plants. Furthermore, all power plants must obtain a licence or permit before they can operate. These may include stricter limits and/or additional pollutants than those tipulated in national standards. Technologies for treating the various waste streams to meet the discharge limits are described; each plant has its own unique needs and hence the choice is site-specific. The trend is towards zero liquid discharge and the reuse of the wastewater as a way of conserving fresh water resources and managing water in a more sustainable way. This will also eliminate the need to meet the discharge regulations.
Wastewater regulations and issues for coal fired power plants
Anne M Carpenter