Cogeneration technology helps landfills reduce wastewater management costs

More than 60% of landfills dispose of their leachate by transporting it to municipal wastewater treatment plants.  Trucking costs, as well as municipal operators’ growing reluctance to accept leachate due to the challenges leachate brings to their treatment processes, are driving up costs of leachate disposal and the costs of managing a landfill.Many landfills over the past two decades have developed valuable waste-to-energy projects, generating renewable energy from the biogas created through the decomposition of organic materials within the landfill. The vast majority of these biogas-to-energy projects are ‘simple cycle’ power generation configurations – meaning the ample energy available in the hot exhaust produced by the power generation equipment is vented to atmosphere and not used beneficially. A landfill in the eastern US is using this hot exhaust energy from its biogas-to-energy plant to evaporate leachate on site using a novel solution by Heartland Water Technology. By using this freely available energy and treating leachate onsite, the landfill is taking positive control over its leachate management, generating even more value out of its renewable biogas, lowering its total cost-to-treat and significantly reducing its dependency on municipal wastewater treatment plants.
 

Heartland Water Technology Signs Contract with Mississippi’s Three Rivers Solid Waste Management Authority

Hudson, MA – December 19, 2017 – Heartland Water Technology, Inc. today announced that it has signed a contract with the Three Rivers Solid Waste Management Authority to install a Heartland Concentrator™ at the Three Rivers Regional Landfill near Pontotoc, MS to treat landfill leachate.  Heartland develops innovative technology to solve some of the world's most challenging waste water problems.

FGD Wastewater Evaporation Pilot Project at Large Power Plant

In the fall of 2015, the U.S. Environmental Protection Agency (EPA) promulgated revised effluent guidelines for steam electric power generating units (EGUs). The 2015 Effluent Limit Guidelines (ELGs) final ruling (1) is now in place. While there is now some uncertainties as to the effective start date for the new guidelines, the tightening discharge limits will certainly impact a number of electric power plants across the United States. Particularly challenging wastewaters in this context include flue gas desulfurization (FGD) purge water and coal combustion residual (CCR) pond waters.

The Electric Power Research Institute (EPRI) conducted a study using a different evaporation technology installed at the Water Research Center at Southern Co.’s Plant Bowen, located in Cartersville, GA. The purpose of this project (2) was to evaluate the efficacy of an adiabatic evaporator for FGD wastewater treatment/concentration at a 952-megawatt (MW) coal-fired power plant. The system used flue gas from the power station as the source of thermal energy for evaporation.

The study revealed that the adbiatic concentrator technology, which uses a direct contact evaporation process, can be a particularly appealing option for sites implementing a ZLD treatment train and without many of the disadvantages experienced by more traditional technologies. Furthermore, there is potential for producing a concentrated slurry that can be stabilized (or solidified) for disposal without the need to add a crystallizer stage to the process. The study validated that the adiatic concentrator offered an alternative to reducing plant wastewater volumes and facilitating efficient capture and disposal of water contaminants in an environmentally responsible manner.