Process for liquid-solid contacting

Process for the continuous contacting of pregnant liquid with absorbent particles contained in a series of horizontally adjacent vessels, wherein normally an incoming pregnant liquid is flowed in a continuous series stream passing upwardly through each vessel in series, whereby the particles are fluidized and receive a loading from the pregnant liquid, and, periodically, the loaded particles from a vessel at the end of said vessel series receiving the incoming pregnant liquid is removed from said end vessel, and a transfer of particles is effected between adjacent vessels in a direction counter-current to the pregnant liquid stream, the batch of loaded particles removed from said end vessel is stripped of its loading, and an initial vessel in the series is replenished with the stripped batch of particles, characterized in that each vessel has its side surfaces converging downwardly adjacent its lower end to a collection zone, and has a particle collection conduit having its inlet opening adjacent the collection zone and extending upwardly and transversely to its outlet in the vessel next adjacent in said counter-current direction, and said particles transfer is effected from each vessel to the next, which at such time is substantially empty of particles, by diverting said series stream to by-pass the vessel from which particles are to be transferred, and to flow to the vessel next adjacent in the co-current direction of the stream, and particles are transferred in a slurry by withdrawing liquid from the vessel next adjacent in the counter-current direction to the vessel which is to receive the particles, and flowing it into the collection zone of the vessel from which particles are to be transferred and up the particle collection conduit and into a lower region of the vessel which is to receive the particles, while withdrawing liquid from the upper region of the vessel which is to receive the particles, until substantially all the particles have been slurried from one vessel to the next.