Many states are already taking steps to limit mercury discharges, and the U.S. Environmental Protection Agency and Congress are considering new federal regulations as well. Nalco, providing expertise for water, energy and air, has expanded its capability to help industry, especially power generators, meet current and pending regulations by reducing mercury emissions, according to the company.
Predict Hg is a new service that allows Nalco's power customers to model their emissions and forecast the expected mercury content by simulating different removal processes.
"Predict Hg uses samples from a customer's own wastewater stream to identify and rank the available chemical and mechanical treatments and identifies the best options to remove mercury from plant wastewater," said Dave Flitman, Nalco senior executive vice president and president, water and process services. "This allows the customer to select practical, cost-effective solutions before making capital investments or expensive process changes to meet or prepare for discharge limits."
Using Nalco Predict Hg, a sample is drawn from a customer's Flue Gas Desulfurization (FGD) wastewater stream and then sent to the Nalco Center of Innovation. There various treatment options are evaluated and the analysis determines the degree of mercury reduction possible, addressing the effectiveness and cost of potential chemical, operational and mechanical methods.
For example, a power plant in Illinois sought to reduce its mercury discharge, but needed to understand the cost of the potential reduction. Nalco evaluated the FGD waste stream, conducted chemical and mechanical evaluations and achieved a 99.7% reduction in FGD wastewater mercury concentrations. Also included in the project were budgetary and technical estimates of the cost to further reduce mercury discharge to achieve a 99.9% total reduction.