Abstract In the reclaiming of plating wastes containing chromic acid and the like, the rinse liquid from the first of a plurality of washtubs into which plated articles are dipped successively to rinse off the plating solution, is sucked into a tower, heated by steam to concentrate it to plating strength, and then is returned to the plating tank. The plating solution is also pumped from the plating tank into the tower where it is heated and recirculated back to the plating tank to maintain the solution in the tank at an elevated temperature. Means is also provided to pump the rinse liquid directly from the first washtub to the plating tank, if the rinse liquid in said first tub does not require concentration to raise it to plating strength.
A recovery unit as defined in claim 1, including means connecting said tank to said first pipe to pump plating solution from said tank through said evaporating chamber for rapid heating thereby before return by said second pipe to said tank.
Claim 2
Dependent Claim
93 words
A recovery unit as defined in claim 1, wherein the first-named means comprises a first pump connected at its inlet end to said last tub and at its discharge end to said first pipe, and a first valve disposed in said first pipe between said first pump and said evaporating chamber, said fourth pipe is connected to said first pipe between said first pump and said first valve, and said bypass means comprises a second valve disposed in said fourth pipe and operable selectively to connect said first pipe to said third pipe.
Claim 3
Dependent Claim
60 words
A unit as defined in claim 3, wherein said recirculating means comprises a second pump connected at its intake end to said plating tank and at its discharge end to said evaporator third pipe, and said valve in said third pipe being disposed between said second pump and the point where said fourth pipe is connected to said third pipe.
Claim 4
Dependent Claim
60 words
A unit as defined in claim 4, including a further pipe connected at its intake end to said third pipe between said second pump and said third valve and at its chamber, end to said chamber and a fourth valve disposed in said further pipe and operable selectively to connect the output of said second pump to said evaporator chamber.