Zero Liquid Discharge (ZLD)
HPD® Wastewater Evaporators and Crystallizer Systems
Press Release: Oil & Gas Downstream
Veolia Zero Liquid Discharge System
Veolia Water Technologies will engineer, procure and deliver a Zero Liquid Discharge system based on its proven HPD® Brine Evaporator and Brine Crystallizer technologies for calcium sulfate seeded slurry processes.
ZLD Expertise in All Major Industries
Fresh water scarcity and concerns for environmental impact resulting from industrial wastewater discharges place a high degree of importance on recycling and reuse of water, an increasingly valuable resource.
As regulatory issues, environmental sensitivity, and long term water supply concerns increase, many industrial companies are considering ways to reduce their water discharges with Zero Liquid Discharge (ZLD) processes.
Veolia has decades of innovation using HPD® Evaporation and Crystallization technology in many wastewater treatment applications including inudstry experience in volume reduction and zero liquid discharge:
Veolia has the expertise to design and build wastewater reduction and ZLD facilities of any size, anywhere in the world. Delivery of a project on a lump-sum, turnkey basis ensures that customers have a single point of responsibility. Veolia also specializes in operation and maintainance of the industrial ZLD facilities for a fixed term.
Process Experience for a Variety of Effluent Streams
Each effluent stream presents its own unique challenge when designing an entire ZLD water treatment system to efficiently and effectively minimize waste or eliminate the discharge of wastewater.
Veolia's experience in treating and managing these streams include specification and complete system design utilizing complementary water treatment expertise from Veolia Water Technologies such as deoiling, softening, clarification, and filtration for the following applications:
- Membrane System Reject (NF, MF, UF, RO)
- Cooling Tower Blowdown
- Flue Gas Desulfurization (FGD) Blowdown / Purge
- Produced Water (Conventional, Fracking, SAGD)
- Integrated Gasification Combined Cycle (IGCC) Gray Water
- Mine Drainage
- Refinery, Gas to Liquid (GTL), and Coal to Chemical (CTX) Wastewaters
- Scrubber Blowdown
- Demineralization Waste
- Landfill Leachate
Evaporation and Crystallization Technologies
Veolia offers several options in designing the optimal system to achieve each unique customer requirement for achieving zero discharge or waste reduction objectives, including recovered water quality, energy consumption, minimization of capital and operating costs, and ease of operation. HPD® Evaporation and Crystallization system capacities range from around 10 gpm to greater than 1500 gpm per unit.
Falling film evaporators, sometimes called brine concentrators, are an excellent technology for efficient heat transfer, producing high-purity distillate, and achieving water recovery greater than 90%. Recovered water in a brine concentrator is suitable as cooling tower or scrubber makeup, and can be recycled to other plant processes, including demineralizer feedwater. These wastewater evaporators can be driven by mechanical vapor recompression (MVR) or with live steam depending on the relative costs of electric power and steam.
Crystallizers are designed to handle continuous crystallization of the various dissolved salts, which sometimes can be recovered as valuable by-products. Wastewater crystallizers are used to concentrate the effluent from brine concentrators, and when equipped with solids dewatering, comprise a true zero liquid discharge system. These brine crystallizers typically are driven by live steam but in some cases can use MVR technology to recycle the vapor to reduce energy usage and operating costs.
Innovative ZLD Systems
Veolia also has several proprietary Innovations that make thermal ZLD systems more affordable and robust. These include the CoLD® Crystallization Process for produced/flowback water from fracking and FGD blowdown, the Silica Sorption process for produced waters from SAGD and steam flood stimulation techniques, and the Modular Bulldozer DesignTM evaporation/crystallization system for coal seam gas produced water and other challenging wastewater applications.