abstract a varying tapered conical shell is provided with a varying taper conical rotor having pinlike radially extending projections whereby the varying taper assures more uniform solids distribution in a fluffing solids gas contactor application_number US 39831795 A description a rotary pin type fluffer contactor has been described in patent application ser no 08 125 053 assigned to the same assignee as the present invention a vertical axis version shown in fig1 uses a conical surface to control the motion of the fibers passing through the machine as shown in fig1 the fluffer is comprised of a conical housing 1 having an inlet 2 and an outlet 3 for receiving pulp fiber and a reagent gas and discharging pulp fiber respectively a pin rotor 4 is shown which is also conical in section and is mounted for rotation within the housing 1 on a shaft 5 which extends through the housing the rotor is further provided with a plurality of pinlike projections 6 which extend from the rotor to a point proximate substantially through the circumferential space formed between the housing and the rotor the internal wall of the housing pulp fibers enter the machine through inlet 2 where they are then caused to be spun about the circumference of the machine by the combing action of the rotor 4.