Abstract: A centrifugal and vacuum pump combination in which the impeller of a centrifugal pump is disposed on the same shaft as a rotor of the vacuum pump, with a gas outlet extending between the centrifugal and vacuum pumps, is operated by positively controlling the flow of gas passing through the gas outlet duct, for example by changing the effective cross-sectional flow area of the outlet duct. The fluent material handled by the pump is preferably a cellulose fiber slurry having a solids consistency of between about 6-15%. The control can be effected automatically in response to solids consistency, inlet pressure, and/or gas content of the slurry being pump. The vacuum pump housing includes an eccentric inner wall, and operation of the pump may be primarily controlled by moving the vacuum pump housing.

Abstract: A centrifugal and vacuum pump combination in which the impeller of a centrifugal pump is disposed on the same shaft as a rotor of the vacuum pump, with a gas outlet extending between the centrifugal and vacuum pumps, is operated by positively controlling the flow of gas passing through the gas outlet duct, for example by changing the effective cross-sectional flow area of the outlet duct. The fluent material handled by the pump is preferably a cellulose fiber slurry having a solids consistency of between about 6-15%. The control can be effected automatically in response to solids consistency, inlet pressure, and/or gas content of the slurry being pump. The vacuum pump housing includes an eccentric inner wall, and operation of the pump may be primarily controlled by moving the vacuum pump housing.

Abstract: An apparatus for the discharge of a mass tower containing medium to high consistency pulp and operable without the need for further dilution includes a vessel for storing the pulp; a suction duct extending from a zone of moving pulp to a region outside of the tower; and a pump attached to the end of the suction duct for discharging the pulp.

Abstract: A method and an apparatus for dividing the flow of fiber suspensions of the pulp and paper industry in which the fiber suspension is caused to flow into a space uniting the inlet and the outlet flows and in which space a vortex flow is created to prevent the suspension from forming a strong fiber network and from causing blockage of the system. The pressure of the suspension further is increased so that the suspension flowing into the apparatus need not be pressurized. The apparatus includes a vortex chamber provided with one inlet and several outlets, at least one of the outlets is preferably provided with a device for regulating the flow through the outlet. The apparatus further includes a rotor for moving the suspension through the several outlets towards further processing devices.

Abstract: A method and an apparatus for dividing and uniting flows of high-consistency fibre suspensions. To prevent clogging of the distributor the fibre suspension is caused to flow into a space unitting the inlet and the outlet flows, where a turbulent flow extending to the valves regulating the discharge flow is created. The distributor includes a vortex chamber provided with an inlet and outlets and with regulating valves connected to the outlets and disposed at a short distance from the outlets. According to a preferred embodiment of the the invention, a rotor provided with vanes is disposed in the vortex chamber.

Abstract: The operation of a centrifugal pump which pumps a liquid or suspension (e.g. 8-12 percent consistency) containing gas is controlled to minimize pump power consumption, or to vary the pump flow rate. The suspension is rotated within the pump so that a gas bubble is created at a central part of the pump, and gas is discharged from the gas bubble, at a gas discharge pressure. The differential pressure between the suspension inlet and the gas discharge is determined, and the head and/or discharge flow rate of the pump are controlled by controlling the differential pressure so determined. The discharge flow rate may be maintained constant utilizing a control valve and flow meter in the pump discharge line, in which case controlling the discharge of gas from the gas bubble controls the head, and minimizes power consumption for a given flow rate. Alternatively the flow rate is controlled by controlling the gas discharge, with no control valve in the pump discharge line being provided.