Metallurgical pickling

Claim 1

THE METHOD WHICH COMPRISES PICKLING A FERROUS ARTICLE BY PASSING IT SEQUENTIALLY THROUGH A SERIES OF PICKLING BATHS OF HOT DILUTE SULFURIC ACID SOLUTION WHEREIN THEREIS A MOVEMENT OF SUCH SOLLUTION FROM BATH TO BATH IN A DIRECTION COUTER TO THE MOVEMENT OF SAID ARTICLE AND AN ACCUMULATION OF DISSOLVED FERROUS SULFATE TO FORM PICKLE LIQUOR OF PROGRESSIVELY GREATER FERROUS SULFATE CONCENTRATION ALONG THE SERIES OF BATHS FROM THE WORKENTERING END OT HTE LEAVING END OF THE SERIES, WITHDRAWING HEATED PICKLE LIQUOR FROM A POINT ADJACENT TO THE WORK-ENTERING END OT THE LEAVING END OF THE SERIES, WITHDRAWDRAWN LIQUOR INTO A PLURALITY OF BATCHES, EVAPORATING A SUBSTANTIAL PORTION OF THE CONTAINED WATER FROM SAID BATCHES SEVERALY WHILE THE HEATED LIQUOR IS BELOW THE TEMPERATURE AT WHICH SULFURIC AACID IS EVOLVED AND EFFECTING A PRECIPITATION OF SUSPENDED FERROUS SULFATE IN THE RESULTING CONCENTRATE, RECOVERING BY GRAVITY SEPARATION THE PRECIPITATED FERROUS SULFATE FROM THE CONCENTRATE, RECOVERING SUPERNATANT LIQUID FROM THE CONCENTRATE IN THE FORM OF A SULFURIC ACID SOLUTION INCLUDING A RESIDUAL QUANTITY OF DISSOLVED FERROUS SULFATE, RETURNING THE RECOVERED SULFURIC ACID SOLUTION TO THE SERIES OF BATHS AT A POINT REMOVED FROM THE WORK-ENTERING END THEREOF, ADDING NEW SULFURIC ACID TO THE SERIES OF BATHS AT A POINT MORE REMOVED FROM THE ENTERING END OF THE SERIES THAN THE POINT AT WHICH THE RECOVERED ACID IS ADDED, AND ADDING WATER TO THE SERIES OF BATHS FOR THE FORMATION OF SAID RECOVERED ACID AND NEW ACID INTO AN ACID SOLUTION OF PICKLING CONCENTRATION.

Claim 2

THE METHOD WHICH COMPRISES PICKLING A FERROUS ARTICLE BY PASSING IT SEQUENTIALLY THROUGH A SERIES OF PICKLING BATHS OF HOT DILUTE SULFURIC ACID SOLUTION WHEREIN THEREIS A MOVEMENT OF SUCH SOLLUTION FROM BATH TO BATH IN A DIRECTION COUTER TO THE MOVEMENT OF SAID ARTICLE AND AN ACCUMULATION OF DISSOLVED FERROUS SULFATE TO FORM PICKLE LIQUOR OF PROGRESSIVELY GREATER FERROUS SULFATE CONCENTRATION ALONG THE SERIES OF BATHS FROM THE WORKENTERING END OT HTE LEAVING END OF THE SERIES, WITHDRAWING HEATED PICKLE LIQUOR FROM A POINT ADJACENT TO THE WORK-ENTERING END OT THE LEAVING END OF THE SERIES, WITHDRAWDRAWN LIQUOR INTO A PLURALITY OF BATCHES, EVAPORATING A SUBSTANTIAL PORTION OF THE CONTAINED WATER FROM SAID BATCHES SEVERALY WHILE THE HEATED LIQUOR IS BELOW THE TEMPERATURE AT WHICH SULFURIC AACID IS EVOLVED AND EFFECTING A PRECIPITATION OF SUSPENDED FERROUS SULFATE IN THE RESULTING CONCENTRATE, RECOVERING BY GRAVITY SEPARATION THE PRECIPITATED FERROUS SULFATE FROM THE CONCENTRATE, RECOVERING SUPERNATANT LIQUID FROM THE CONCENTRATE IN THE FORM OF A SULFURIC ACID SOLUTION INCLUDING A RESIDUAL QUANTITY OF DISSOLVED FERROUS SULFATE, RETURNING THE RECOVERED SULFURIC ACID SOLUTION TO THE SERIES OF BATHS AT A POINT REMOVED FROM THE WORK-ENTERING END THEREOF, ADDING NEW SULFURIC ACID TO THE SERIES OF BATHS AT A POINT MORE REMOVED FROM THE ENTERING END OF THE SERIES THAN THE POINT AT WHICH THE RECOVERED ACID IS ADDED, AND ADDING WATER TO THE SERIES OF BATHS FOR THE FORMATION OF SAID RECOVERED ACID AND NEW ACID INTO AN ACID SOLUTION OF PICKLING CONCENTRATION.