Case Study: Quench Water after Molten Salt Bath

SYSTEM: Automotive Remanufacturing
APPLICATION: Quench Water after Molten Salt Bath
PARTICULATE SEPARATED: Metal Hydroxides and Fines
PROCESS EQUIPMENT: Heavy Metal Extraction

PROBLEM:
Engine blocks, crankshafts and oil pans are immersed in 750° F molten salt and then cold quenched in a 2200-gal process tank whose hydroxide, TSS and TDS concentrations quickly elevate, requiring daily refresh to maintain product quality. High maintenance and water/wastewater treatment costs are associated with this arrangement. A cooling tower, sidestreaming the cold quench tank, obstructs with metal hydroxides precipitating and accumulating in the tower, degrading its cooling capacity.

SOLUTION:
EFS installed its Clariflo^® Industrial Clarification System, sidestreaming the cold quench tank. By additionally cascading process tanks within the system, daily water consumption decreased from 3300 gpd to 300 gpd. Product throughput is increased while maintenance and water/wastewater costs are greatly reduced. Product quality is improved at a much lower cost. Heavy metals are disposed in solid form rather than as dissolved solids in wastewater streams. The cooling tower is not obstructed anymore and average salt levels in the cold quench tank are desirably much lower on average than before. Clariflo^® proved to be an outstanding addition to Kolene Molton Salt Cleaning System.

(Left) Engine blocks, crankshafts and oil pans to be cleaned. (Right) Clariflo