US Patent 9410414 Environmentally sealed system for fracturing subterranean formations

An environmentally sealed system for fracturing subterranean systems including a fracturing fluid source, a proppant source, a proppant hopper comprising a variable proppant regulator, a blender comprising a blender inlet and a blender outlet, a high pressure pump comprising a high pressure pump inlet and a high pressure pump outlet, and a well head; wherein the fracturing fluid source is connected to the blender inlet through a fracturing fluid supply connection and a fracturing vapor recovery connection, the proppant source is connected with the proppant hopper through a proppant supply connection and a proppant vapor recovery connection, the proppant hopper is connected to the blender inlet through a proppant transfer connection, the blender outlet is connected to the high pressure pump inlet, and the high pressure pump is outlet connected to the well head.