| 主权项 |
1. A process for continuously or semi-continuously washing biomass to selectively remove at least a portion of detrimental metals and their anions (“detrimental species”) from a detrimental species-containing cellulosic biomass solids for further processing in a hydrothermal digestion unit comprising:
a. continuously or semi-continuously providing a detrimental species-containing cellulosic biomass solids into a generally cylindrical vessel comprising a chamber having a height that is greater than its width, the height comprised of height from top to bottom L0, L1 , L2, L3, L4 and L5; the chamber having an opening suitable for solids introduction located within L0, one or more first fluid conduits connected to the chamber within the lower 20% of its height within L1, one or more second fluid conduits connected to the chamber within the upper 20% of its height within L1, said cellulosic biomass solids flow in only one direction within the chamber and countercurrent flow relative to the direction of fluid flow within the chamber, one or more third fluid conduits connected to the chamber within the lower 20% of its height within L2, one or more fourth fluid conduits connected to the chamber within the lower 20% of its height within L3, one or more fifth fluid conduits connected to the chamber within the lower 20% of its height within L4, one or more sixth fluid conduits connected to the chamber within the lower 20% of its height within L5, the chamber having an opening suitable for biomass extraction located within the lower 20% of its height within L5 downstream from the one or more sixth fluid conduits for the cellulosic biomass solids; at least one solvent and/or water detection device within the vessel or in fluid communication with the vessel located within L5, L4, L3, L2, L1 and/or in within or in fluid communication with the one or more second fluid conduits; at least one pH detection device within the vessel or in fluid communication with the vessel located within L2, L1 and/or in within or in fluid communication with the one or more second fluid conduits; a solvent flow control device within the vessel or in flow communication with the vessel to control the flow of the solvent; an aqueous flow control device within the vessel or in flow communication with the vessel to control the flow of the first aqueous solution; b. introducing acid or base to the vessel from the one or more first conduit to contact with the biomass solids; c. introducing aqueous solution to the vessel from the one or more third conduit to contact with the biomass solids; d. introducing base if step b is acid or acid if step b is base to the vessel from the one or more fourth conduit to contact with the biomass solids; e. introducing a second aqueous solution to the vessel from the one or more fifth conduit to contact with the biomass solids; f. introducing solvent to the vessel from the one or more sixth conduit to contact with the biomass solids producing biomass containing solvent; g. removing aqueous solution from the vessel from one or more second fluid conduit; and h. removing the biomass containing solvent from the vessel from biomass extraction opening; wherein the solvent and/or aqueous solution is introduced at a rate such that the concentration of solvent or aqueous solution at the solvent and/or aqueous detection device is within a predetermined level and the first aqueous solution is introduced at a rate such that the pH is within a predetermined level at the pH detection device. |
