Agitation and evacuation of refinery solids waste

A method of evacuating a refinery tank containing waste with solid constituents, the method comprising:

• inserting an agitator through a first opening in a top of the refinery tank;
• agitating waste in a first area of the refinery tank to cause the waste in the first area to have a first viscosity greater than a second viscosity of waste in a second area adjacent the first area;
• removing agitated waste of the first viscosity through the top of the refinery tank;
• opening a second opening on the side of the refinery tank, wherein a bottom edge of the second opening is at least one foot above a top surface of the waste in the refinery tank;
• removing waste of the second viscosity from the second area of the refinery tank via the second opening;
• expanding the second opening downward toward a floor of the refinery tank;
• inserting an excavator into the refinery tank via the expanded second opening;
• and
• removing waste of the second viscosity using the excavator.

A method of evacuating a refinery tank containing waste with solid constituents, the method comprising:

• cutting a first opening in the refinery tank above an initial top level of waste;
• inserting an agitator into the refinery tank through a first opening;
• agitating the waste in a first area of the refinery tank to cause waste in the first area to have a viscosity greater than a viscosity of waste in a second area at a periphery of the first area;
• removing the waste from the first area;
• expanding the opening downward to a location above the bottom of the first area;
• agitating the waste at the bottom of the first area to cause waste beneath the bottom of the first area to have a viscosity greater than a viscosity of waste in a second area at a periphery of the first area;
• removing the waste from the bottom of the first area to reach an expanded bottom of the first area;
• and
• expanding the opening downward to a location above the expanded bottom of the first area.