A Midwestern coal-fired power plant injected a lime reagent into a Spray Dryer Absorber (SDA) to control the emission of sulfur dioxide. The power plant recovered unspent lime from fly ash created during the combustion process. The fly ash was mixed with fresh lime to create a neutralizing lime slurry. The slaking tanks, 15’ (4.6m) in diameter by 25’ (7.6m) deep, required weekly cleaning – a labor intensive operation. Manual cleaning of the limestone residue from tank interiors with high pressure washers could take up to eight hours to complete and required an OSHA permit for confined entry. The cleaning process was costly and dangerous.
Spraying Systems Co.’s TankJet® AA190E solved the customer’s cleaning problem. The motorized TankJet unit provides effective cleaning of the entire tank interior. Hot water, provided by the customer, is pumped to the tank cleaner by the fluid delivery system at 120 psi (8 bar) with a flow rate of 25 gpm (95 lpm).
The three-foot shaft of the TankJet unit is equipped with WashJet® solid stream nozzles which provide effective cleaning of interior tank surfaces. Cleaning time now just takes 45 minutes compared to the eight hours required with pressure washers.