Heat Transfer

Kadant evaporators are perfectly suited for liquor concentrations below first critical solids (between 45-55%TS) and are specifically designed to reduce foaming. They offer high turndown capabilities which provide operating flexibility and feature efficient condensate segregation through special baffling and our unique cross-flow, shell-side design.

For potentially heavy scaling applications above critical solids, Kadant falling-film crystallizers use high recirculation rates (for low supersaturation) and large liquor volumes (for residence time and crystal growth). This promotes the precipitation of sodium salts as crystals within the liquor not as scale on the heat transfer surfaces. Online washing capabilities eliminate the need for concentrator boil-outs altogether.

Another option for the processing of high solids black liquor is our enhanced, forced-circulation crystallizers which rely on increased turbulence to achieve higher heat transfer performance at reduced recirculation rates. This technology is specifically invaluable when processing liquors of an excessively high viscosity or exhibiting unusual fouling and scaling tendencies. The enhancer technology can easily retrofit onto older traditional non-enhanced crystallizers to reduce power consumption, raise the liquor dry solids content and increase time between boil-outs.

The Kadant Cross-Flow Condenser provides high-efficiency condensing, segregation, and NCG pre-cooling with compact technology that out performs conventional serpentine systems. Our optimized design minimizes pressure drops across the condenser while meeting strict heating area requirements. It also delivers superior NCG handling by controlling the sectional flow in the condenser to minimizing vapor loss.