Patent EP-2127748-A1 (EP)
Inventor: LE VOT SOPHIE
IPC: G01N15/02
Filed: 2009-05-12
Abstract: The process comprises focusing a particle along a wall (7) of a main channel (1) by focusing a device in downstream region in a first region of the main channel, collecting the particles in a sorting device, and sampling in communication with the main channel by an opening so that a selection of collected particles are produced by the sorting device and sampling depending on the size of the particles. The particles have a density different from that of the fluid. The first region has a constant section in which the focusing is carried out by an injection in the main channel of a fluid. The process comprises focusing a particle along a wall (7) of a main channel (1) by focusing a device in downstream region in a first region of the main channel, collecting the particles in a sorting device, and sampling in communication with the main channel by an opening so that a selection of collected particles are produced by the sorting device and sampling depending on the size of the particles. The particles have a density different from that of the fluid. The first region has a constant section in which the focusing is carried out by an injection in the main channel of a fluid from the focusing device that has a side channel under an angle of incidence of 90[deg] for focusing the particles on the wall of the main channel in downstream of the region where the lateral injection is carried out. The extraction of particles is carried out at the opposite of the injection region and/or in its downstream using a channel. The dimension of the extracting channel is less than the finest particles circulating in the main channel. The device for sorting and extracting is a recirculation chamber (40) contacting with the main channel, and has a recirculation area to concentrate the collected particles and a unit of sequential extracting. The average speed in the main channel is 1-50 mm/s. The speed in a recirculation area is 5-1000 mu m/s. The recirculation chamber is coupled with a leak venting channel. The sorting and sampling device is a transverse channel contacting with the main channel and coupled with a pumping unit to ensure a continuous extracting. An additional focusing device is placed between two such sorting and extraction devices in cascade. A row of pillars is inclined with respect to the axis of the main channel and extends between the wall of the main channel along which the focusing takes place and the opposite wall to deflect the particles of the diameter greater than a given diameter. The row of pillars is laid in downstream of a focusing device and between the device and a recirculation chamber. An enlarged region of the main channel constitutes the recirculation chamber, and comprises an upstream wall perpendicular to the axis of fluid movement in the main channel. The recirculation chamber is present in the form of pseudo-rectangular, circular or polygonal form. The leakage flow in the leak venting takes place continuously with an adjustable flow for selecting the particle size. The flow in a leak venting is 0.1-500 mu l/h. An independent claim is included for a device for sorting particles moved in a fluid flowing in an axial direction of a main channel.