Abstract:
A mechanical fluid separator defines an interior chamber for centrifugally separating entrained media from a fluid stream. The mechanical fluid separator has a fluid inlet connecting the interior chamber with a media entrained fluid source. A cone shaped baffle disposed within the mechanical fluid separator defines a conical surface having a concave surface and a convex surface. The conical surface has an annular base side and an annular apex side. The base side terminates in a circumferential rim contacting the annular chamber surface above the fluid inlet and said apex side terminates in an apex annular hole. The fluid stream is centrifugally directed in a first direction about the annular chamber surface and the convex surface of the conical baffle to disentrain the entrained media from the fluid stream. The disentrained fluid stream then passes through a window in the cone shaped baffle and escapes through a fluid outlet.
Abstract:
A chamber having a slurry-admitting inlet (14) at one end has a metering opening (18) lengthwise thereof for feeding slurry to an associated slurry processing machine. A rotatable bar (20), having a plurality of spaced-apart grooves formed therein, is disposed in immediate proximity to the metering opening (18) to control slurry-flow through the opening. The grooves insure that access to the opening, by the slurry, will be greater than the largest floc diameter of the pulp at all operating conditions.
Abstract:
A wall passageway, having openings therein only at opposite, inlet (14) and outlet (18) ends thereof, has a shaft (22) journalled therein. The shaft carries a screw thereon for moving shredded pulp through the passageway. The screw (24) is foreshortened, having a length less than that of the passage way, and causes inlet-admitted pulp to form into a continuously moving pulp plug. The plug, albeit having some porosity, comprises a gas seal within the passageway, and inhibits any migration of downstream gas from escaping to the atmosphere via the passageway and the inlet (14) thereof. In addition, a source (32) of oxygen or such gas as is inert to any downstream process is controllingly admitted into the inlet (14) to maintain an upstream pressure equal to, or greater than any downstream process pressure to insure against release of downstream gas into the atmosphere.
Abstract:
A washer drum is provided having a rotating cylinder (2) with unique cross bracing (15) which prevents twisting, reduces vortex formation in radial inflow ports (6) formed between the outer head (11) and two adjacent radial ribs (21), and further provides support for the decking (23) between closely spaced intermediate heads (11).
Abstract:
A method for bleaching cellulosic and lignocellulosic pulp using hydrogen peroxide as a bleaching reagent, utilizes a two-step reaction, viz. a short high temperature step at a pressure sufficient to suppress boiling and a longer atmospheric pressure reduced temperature step to consume a substantial portion of the hydrogen peroxide remaining after the short phase. The method includes the steps of introducing pulp (15), at a consistency of 10 %-18 %, to a mixer (100) in which the pulp is heated to a temperature above 100 DEG C; adding sufficient sodium hydroxide to bring the pulp to a pH of 8.5; adding sufficient hydrogen peroxide (36) to equal from about 0.5 %-5.0 %, by weight, of the pulp; passing the pulp through a pressurized reactor column (400) at a rate providing a reaction time in the column of between 1 and 30 minutes; and depositing the pulp in a reaction tower and allowing the reaction to proceed for 1-5 hours until a substantial portion of the residual hydrogen peroxide has been consumed. It may be desirable to introduce the pulp to a mixer and add alkali to reactivate residual hydrogen peroxide by bringing the pulp to a pH of at least 9 between bleaching steps.
Abstract:
A pulp bleaching line has an initial stage (140) using gaseous bleaching reagent followed by its subsequent stages (70) without intervening washing or pumping steps. The pulp is transported from the initial stage through a mixer (30) in which the pulp is heated and/or dosed with bleaching chemicals and through the subsequent stage by retained gas pressure developed in the initial stage. A portion of the retained gas may be separated and purged from the mixer through a pressure regulating device (90) to optimize pressure for processes which follow the mixer/heater. This permits elimination of a washer and pump normally provided between the initial reactor and subsequent bleaching stage.
Abstract:
An apparatus for regulating a compressor lubrication system includes an oil-flooded rotary gas compressor, a reservoir flow connected to the compressor, a heat exchanger for cooling a lubricant, and a controller. A thermal mixing valve regulates the temperature of the lubricant flowing to the compressor. A first temperature sensor measures a discharge temperature at a compressor outlet, and provides a signal corresponding to the discharge temperature to the controller. A second temperature sensor measures a lubricant temperature at a lubricant inlet to the compressor, and provides a signal corresponding to the lubricant temperature to the controller. A pressure sensor measures the pressure at the outlet of the compressor, and provides a corresponding pressure signal to the controller. A valve means continuously regulates the supply of lubricant to the compressor, the valve means being controlled by the controller in response to the temperature signal of the first temperature sensor and the pressure signal. Operation of the thermal mixing valve is controlled by the controller, in response to the temperature signal of the second temperature sensor, to continuously regulate the temperature of the lubricant supplied to the compressor to minimize preheating of the low pressure gas.
Abstract:
A method and apparatus for regulating reaction rate between a gaseous bleaching reagent and wood pulp in a bleaching system, of the type having a mechanically agitated pulp contactor (120), including the steps of co-currently or counter-currently introducing a recirculated contacting gas (R) for diluting freshly supplied reagent gas (F) and for thereby reducing the initial reaction rate between the reagent and pulp. Except for the initial reaction rate, overall bleaching performance is quite insensitive to wide variations in the amount of recirculating gas (R) introduced. This allows adjustment of flow rate to control gas velocity through the contactor (120) for purposes of overall bleaching efficiency. Degradation of pulp fibers due to overbleaching is virtually eliminated, and uniformity of bleaching is greatly enhanced without any sacrifice in production rate.
Abstract:
Disclosed is a modular reverse switch assembly having a rotating disc actuation member (8) with a plurality of extending tabs (5) which are spaced apart to project to opposite sides of the tool thereby permitting ease of operation by either hand. The modular design permits a wide degree of selection in assembly location and practice.
Abstract:
A method and apparatus for enhancing knot transport in a knot drainer has a provision for decreasing tangential velocity of the feed slurry in the inlet chamber (10), a hydrodynamic force reduction provision in the screening chamber (20), and a provision for increasing the ratio of circumferential friction forces to axial friction forces in a housing extension (40) above the screening chamber (20). This drastically reduces frequency of knot transport interruptions which would otherwise occur in the knot drainer, thereby improving knot drainer performance efficiency.