A professional who tends equipment that mixes diatomaceous earth, milk of lime, and acid with liquors and syrups to form slurry for filtration process. Respnsibilities include:

• Turns valves to regulate flow of slurries through series of blow-up tanks, and to maintain temperature, content level, and air agitation in tanks.
• Adds milk of lime or phosphoric acid to slurry to obtain specified alkalinity.
• Tests slurries for density, using refractometer, and adds liquor or diatomaceous earth to maintain specified density.
• Tests samples of slurries to ascertain that specified purification is occurring.
• Records operating data on forms or blackboard.
• Prepares phosphoric acid solutions of specified concentration for use in filtration process.
• Cleans blocked lines and blow-ups.