Patent KR-20080013819-A (KR)
Title: Process and device for simulated moving bed separation with a reduced number of valves
Inventor: HOTIER GERARD
IPC: B01D15/02
Filed: 2007-08-08
Abstract: A process and a device for simulated moving bed separation with a reduced number of valves are provided to reduce the number of controlled two-way valves while maintaining the advantage of being able to provide effective flushing of dead zones of the "long duration with a small or non-concentration gradient" type, and increase the reliability of the system by reducing the number of valves, thereby limiting the statistical risks of malfunctioning of the valves. A device for separating at least one desired compound from a mixture comprising the compound by simulated moving bed adsorption is characterized in that: the device comprises at least one column divided into a plurality of adsorption beds(Ai) separated by distributor/extractor plates(Pi) for sequentially supplying and extracting at least two supply fluids and at least two recovery fluids, the supplying fluids being a feed(F) and a desorbant(D), the recovery fluids being a raffinate(R) and an extract(E), and the distributor/extractor plates being disposed between the adsorption bed(Ai) and the immediately inferior bed(Ai+1); the device also comprises networks of fluids, i.e., at least a feed network, a desorbant network, a raffinate network and an extract network, each of the networks being connected to the column through a plurality of lines including controlled two-way isolation valves designated as network valves for sequentially supplying or recovering the fluids; the column is divided into a plurality of overlapped adjacent sectors, over at least the major portion of its height, each sector essentially being comprised of a group of at least two and at most five successive adsorption beds and distributor/extractor plates(Pi) disposed immediately below the successive adsorption beds; each of the distributor/extractor plates of each of the sectors is a single common network for sequentially supplying and recovering fluids(F,D,R,E); the plates(Pi) of each sector are connected to one another through external bypass lines(Lk) connected to each plate of the sector through a connecting part comprising a single controlled two-way isolation valve belonging to the plate(Pi), which is designated as the plate valve(Vi), for sequentially supplying or recovering the fluids into or from the plate; each of the bypass lines includes at least one controlled means for limiting the flow rate in the bypass lines, the controlled means being installed either on the line(Lk) or in a bypass around a plate valve(Vi) of a plate(Pi) of the sector; each of the bypass lines of each of the sectors is connected to each of the networks through a single line including single network valves(VFK,VDK,VRK,VEK) for sequentially supplying or recovering the corresponding fluids to or from the sector under consideration; and each plate of the sector is uniquely connected to each of the networks through, successively, a connecting part including the plate valve(Vi), at least a portion of the bypass line, and then the single line including the single network valves. Further, each sector comprises two or three adsorption beds.