Method and apparatus for removing sludge deposits from oil storage tanks

A system for removing sludge deposits in oil storage tanks, the system comprising:

• an assembly comprising:
• a manway cover attachable to a manway of a tank;
• a flange member provided on the manway cover with an aperture passing through the manway cover and inside the flange member;
• a valve operatively connected to the flange member;
• a spool operatively connected to the valve at a first end and having a flange at a second end;
• and
• a cover attachable to the flange at the second end of the spool and having an opening passing therethrough, and
• a jet nozzle comprising:
• a rigid conduit having a proximal end and a connection end, the connection end connectable to a pressurized liquid supply and the rigid conduit sized to slide through the opening in the cover of the assembly;
• a pivotal connection connected to the proximal end of the rigid conduit;
• a spray nozzle having a proximal end and a discharge end, the proximal end of the spray nozzle connected to the pivotal connection so that the spray nozzle can pivot around the proximal end of the spray nozzle;
• and
• at least one movement actuator operative to pivot the spray nozzle around the pivotal connection.

A method for retrofitting an assembly on a tank for removing sludge deposits in the tank, the method comprising:

• attaching a flange member onto the manway cover;
• connecting a valve to the flange member;
• connecting a first end of a spool to the valve;
• connecting a cover having an opening passing therethrough to a second end of the spool;
• passing a hole saw through the opening in the cover, opening the valve and using the hole saw to cut a hole in the manway cover;
• retracting the hole saw back through the valve and closing the valve;
• removing the cover and installing a jet nozzle passing through the opening in the cover;
• and
• reattaching the cover to the second end of the spool with the jet nozzle extending inside the spool.