System and method and apparatus for maintaining a pressure balance in a solids flow loop and for controlling the flow of solids therethrough

A system for pressure balancing and controlling the flow of solids within a solids flow loop of a chemical reaction system, comprising:

• a downcomer standpipe having an upper end, which receives solids of the power plant, a lower end, an inlet intermediate the upper end and the lower end and configured to receive a gas for passage into the flow of solids within the standpipe, and an outlet intermediate the inlet and the lower end of the standpipe;
• a sealpot having an inlet fluidly coupled to the lower end of the standpipe and an outlet fluidly coupled to a discharge passageway, the sealpot being configured to receive the solids from the lower end of the standpipe and to transport the solids to the discharge passageway;
• and
• a drain device fluidly coupled to the outlet in the standpipe and being configured to facilitate removal of the gas from the flow of solids within the standpipe, wherein the drain device includes a solids and gas separation device for receiving the gas from the standpipe, and a bypass conduit fluidly coupled at one end to the solids and gas separation device and at another end to the discharge passageway, the bypass conduit facilitating the free flow of excess gas between the discharge passageway and the standpipe while bypassing the sealpot.

A method of pressure balancing and controlling the flow of solids within a solids flow loop, comprising the steps of:

• providing a supply of gas to a standpipe at an inlet to facilitate a flow of solids through the standpipe;
• removing at least a portion of the gas from the standpipe at an outlet positioned downstream from the inlet;
• and
• diverting the gas removed from the standpipe around the sealpot to a location within the flow loop downstream from the sealpot.