Pigment-Based Treatments Neutralize Colored Mix Washout
- Written by Concrete News
Sources: GrayAgain LLC, St. Paul, Minn.; CP staff
Citing significant potential to minimize mixer truck and plant mixer process-water volume and downtime, GrayAgain introduces a product that converts integrally colored mix loadsÌ rinse water to neutral gray. Hundreds of gallons of rinse water traditionally used in these conditions will be reduced to 10 gallons, the company notes, and time waiting to fill and discharge process water diminished. Following full colored mix discharge, 10- or 20-lb. water-soluble GrayAgain bags are loaded along with 10 gallons of water into truck or plant mixers. Product developers recommend a 10-minute mixing cycle, but note that color neutralization of wall, paddle and fin residue can occur in as little as three to five minutes.
GrayAgain agents are formulated from finely ground iron-oxide pigments and surfactants. A treatment guide covering major pigment manufacturersÌ color selections is used for recommended dosages. Producers stocking the full treatment line should be able to process 95 percent of the colored residue washout they are likely to encounter. The treatment agents meet or exceed ASTM C 979, enabling producers to use mixers immediately following neutralized rinse water discharge without compromising a new load's set time, finishing characteristics or air entrainment. Û www.grayagain.com