Gas tight shale shaker for enhanced drilling fluid recovery and drilled solids washing

A process for separating solid drill cuttings from oil-based drilling mud mixture containing said solids, said process comprising:

• providing a gas-tight shale shaker including a vibrating screen bed, an inlet at a first end of said vibrating screen bed, a solids outlet at a second end of said vibrating screen bed, and a gas-tight cover above said vibrating screen bed enclosing a gas-tight interior;
• introducing an oil-based drilling mud mixture containing solids into said gas-tight interior through said inlet;
• adding at least one diluent to the introduced oil-based drilling mud mixture containing solids at a rate sufficient to reduce the plastic viscosity of a liquid phase of the introduced oil-based drilling mud mixture containing solids;
• purging said gas-tight interior with a purging gas until said gas-tight interior has an oxygen level at or below a minimum oxygen level required for ignition of said at least one diluent;
• maintaining said gas-tight interior by preventing said at least one diluent from escaping from said gas-tight interior, while at the same time preventing air containing oxygen from being introduced into said gas-tight interior from an external environment;
• flowing said introduced oil-based drilling mud mixture containing solids over said vibrating screen bed to cause a least some liquid to pass through the vibrating screen bed, while at least some solids remain above the vibrating screen bed;
• and
• allowing said at least some solids that remain above the vibrating screen bed to exit said gas-tight interior through said solids outlet.