Heartland Technology’s unique water management technologies offer significant advantages when applied to industrial wastewater management by enhancing or supplanting conventional processes for mass and heat transfer, especially where these unit operations are applied to feed streams that contain significant quantities of total solids. Primary examples of these attributes are evaporative concentration of wastewater streams to reduce volume even to the point of zero liquid discharge (ZLD).
Conventional evaporators apply heat exchangers to add thermal energy as required for evaporation and often include mechanical vapor recompression (MVR) to improve thermal efficiency. Because heat exchangers used in such service will become fouled with deposits of solids over time, in-process fluid is traditionally transferred to a second unit operation, a crystallizer, before the saturation point at which solids begin to precipitate from solution is reached.
In stark contrast, without need for heat exchangers as in MVR and other conventional units, while utilizing opportune sources of waste heat as principal energy sources, Heartland’s LM-HT® Wastewater Concentrators operate continuously at equilibrium solids concentrations well beyond the point of saturation and thereby eliminate the need for the second stage crystallizer. ZLD may then be reached by applying simple and reliable conventional solid-liquid separation devices to remove precipitated solids while either or both of saturated supernatant liquid and filtrate is returned to the evaporative section.
Other examples of the utility of Heartland’s technology include processes for managing effluent from fluid scrubbers, such as in flue gas desulfurization (FGD). Indeed, in this case, the wet scrubber and effluent treatment processes may be combined as a single scrubbing/concentration process within an LM-HT® Wastewater Concentrator. While the above example deals with removal of SOX, the concentrators may also be fitted as the heart of a simple and reliable process to manage wastewater containing ammonia that includes concentration of the feed wastewater stream while removing and recovering ammonia for reuse.