FI70085B - ADJUSTMENT OF AUTOMATIC BUDGETING FOR VAT FIELDS FOR FIBER FIXED PENSION - Google Patents

Abstract

This device employed for example in the paper manufacturing, is used to adjust directly the reaction process. Such devices must have a good response to the behaviour of the fibre material in the paper machine, a reduced maintenance time and a failure-free operator. This device comprises a flow pipe (12) closed at its lower end by a wire sieve (13) and which may tilt about a horizontal axis (36) in a vertical plane. Hence, either the upper opening (14) thereof may be aliyned with a product input (8), or the lower sieve (13) may be brought under a washing device (40). The pipe (12) is filled up to the overflow (15) with a product sample and it is cause to flow through the sieve (13). The amount of filtrate collected in a measuring beaker (27) during a predetermined time interval (after a previous flowing period) is the value searched for.

Description

ΓΒ1 ANNOUNCEMENT NnAQt; Äfi ™ (11 ^ UTLÄGGNINGSSKRIFT / UUÖ3 C (45) Patent! R:; 'L'. 'U;.; · Tty

Patent r.ePtclat 12 CO 1000 (51) Kv.lk.4 / lnt.CI. * G 01 N 15/08 FINLAND · —FINLAND (21) Patent application - Patentansöknlng 792886 (22) Application date - Ansökningsdag 17-09.79 (Fh ' * (23) Start date - Giltighetsdag 17-09 * 79 (41) Has become public - Blivit offentlig 19.03.80

Patent and Registration Office ,,,, ....... .... . ,,. ,,.

* _ (44) Date of publication and date of issue. -

Patent- och registerstyrelsen 'Ansökan utlagd och utl.skriften publicerad 31-01, 86 (32) (33) (31) Pyydetty etuoikeus — Begärd priority

Germany 1 i i ttotasava1ta-Förbundsrepubliken Tysk 1 and (DE) P 2840539-2 Proof-Styrkt (71) Haindl Papier GmbH, Georg-Haindl-Str. 4, 8900 Augsburg, Federal Republic of Germany-Förbundsrepubliken Tyskland (DE) (72) Paul Eirenschma1z, Peiting (Birkland), Xaver Schmid, Peiting,

Federal Republic of Germany-Förbundsrepubliken Tyskland (DE) (74) Oy Kolster Ab (54) Device for the automatic determination of the water transfer capacity of a fiber suspension - Anordning för upprepad automatisk bestämning av vat-tenavgivningsförmägan hos en fiberämnessuspension

The invention relates to a device for repeated automatic determination of the desirability of a pulp stock, comprising a device for feeding the pulp stock, closed on one side by a wire bottom and open at its opposite filling end, rotating about a horizontal axis in a vertical plane being directed downwards, on top of the filtrate recovery device for collecting and measuring the filtrate flowing through the wire bottom, and further with the wire bottom being directed substantially upwards, under the rinsing device.

A device known in the art, especially in the field of papermaking, for determining the permeability of pulp pulp in the laboratory has long been known in German-speaking countries as Schopper-Riegler-Gerät and in Anglo-Saxon countries as Canadian-Freenes-Tester. For a long time, however, the goal has been to be able to perform the permeability determination automatically intermittently or continuously on 2,70085 immediately during pulp production, e.g. for a paper machine, so that direct conclusions can be drawn about the pulp pulp behavior in the paper machine and the corresponding adjustment measures in the paper machine without significant delay.

Above all, such in-process measuring devices must meet two important requirements. First, the measurement results obtained from them must be reproducible in relation to the actual infiltration behavior of the pulp on the paper machine wire or the dry steam control pressure in the paper machine. Another equally important requirement is that the equipment be operated with the least possible maintenance and without interruption, if the aim is for the machine's maintenance personnel to be able to rely continuously on the results given by the measuring device.

On the one hand, there has been no lack of attempts to automate operations po. on the other hand, a number of redesigned measuring devices have also been proposed for the stated use.

The operation of these devices differs in that the pulp sample is dewatered either under its own variable pressure in its own liquid column, under its own pressure in a constant liquid column, under hydrostatic overpressure or under the pressure on the side of the wire from which the filtrate flows out, and a time is determined. the amount of filtrate, the amount of filtrate that drains out in a certain time, or the vacuum created on the filtrate discharge side of the wire, in which case a constant pre-leaching time or a pre-leaching time can be arranged before the actual measurement time, during which a certain amount of filtrate is obtained.

The measuring devices are designed either to periodically filter the sample on the stationary wire surface and then clean the wire again, or to filter continuously on the moving wire surface in successive zones and then to carry out the cleaning again. In these two types of devices, two main types must be distinguished, one in which the pulp is infiltrated from top to bottom through the wire and the wire is cleaned from below, and in the other the pulp sample is pressed mainly from below against the wire and the wire is then sprayed from top to bottom. In such devices, the cleaning of the wire is generally difficult and requires considerable amounts of water to flush the pulp formed on the wire cloth out of the measuring zone against gravity. The latter devices require the maintenance of constant seepage or dewatering conditions

II

70085 usually has a relatively large amount of construction costs. However, in continuous testing devices using a rotating wire (wire cylinder) with a horizontal axis, it is possible to perform both infiltration and rinsing in the most favorable wire position, but construction of these devices also becomes relatively expensive.

It is an object of the present invention to provide a simple device of the type mentioned above which gives measured values or results which are reproducible in relation to the actual infiltration behavior in the paper machine and the required vapor pressure for drying and which operates to such an extent maintenance-free, trouble-free and free from external influences. , that the measured values obtained provide a reliable control variable for immediate corrective action in the process.

This object is solved by a device as described above, which according to the invention is characterized in that the horizontal pivot axis of the dewatering vessel is fixed, that the downcomer and filtrate recovery device are arranged on a vertical line , and that the drive is designed as a rotary drive acting on the horizontal pivot axis of the dewatering vessel, by means of which the dewatering vessel can be pivoted under time control under the downcomer and simultaneously into the wire bottom on the filtrate recovery device or on the wire bottom.

If the mass flow is to flow continuously through the downcomer of the pulp feeder, then the dewatering pipe must be allowed a translational movement in addition to its pivoting movement to be transported under the downcomer and again removed from the pulp wire after reaching the required filling height. Such a device is preferably designed such that the horizontal pivot axis of the dewatering pipe is in turn mounted at a certain distance from the dewatering pipe to rotate vertically about the axis so that the dewatering pipe is movable with its is formed as a filtrate receiving trough a certain length of arc below this horizontal circular path, that the drive is a constant speed rotary drive acting on a vertical axis of rotation, and that the rotary drive

The pulp feeder may also be provided with a closing member in a suitable form. In this case, the downcomer associated with the mass overflow box should be as short as possible and the closure member as close as possible to the overflow box. The closing member has proven to be a very advantageous reversing flap during the day than the rather disturbance-prone pressure valves used in one known type of device. The device in which the downcomer of the pulp feeder is provided with a closing member does not need the displacement of the drainage pipe and is suitably designed so that the horizontal pivot axis of the drainage pipe is arranged in place. from the downcomer to the pivot plane of the drainage pipe and the drive is formed as a rotary drive acting on the horizontal pivot axis of the drainage pipe, whereby the filling end of the drainage pipe is below the downcomer and its wire bottom under the rinsing water outlet can be turned in synchronism.

In order for the additional filtrate, the rinsed mass and the rinsing water receiving device to be used, the dewatering pipe immediately with its components is preferably surrounded by a receiving vessel with a funnel-shaped downcomer at the lower end. The resulting mixture of pulp and water can be returned to the process. In order to avoid heavy splashing of the pulp when filling the drainage pipe, this is suitably provided with an obliquely downward side overflow pipe, so that the surface of the pulp inside the pipe can only rise up to the upper edge of this pipe.

The dewatering pipe used to determine the permeability of pulp stock with a consistency of 3.5 ... 5.5% can be, for example, about 400 ... 1000 mm long and 50 ... 150 mm in diameter.

It has been found that the device according to the invention gives results which are excellently correlated with the behavior of the pulp in the paper machine. In addition, the device operates virtually maintenance-free.

Il 5 70085

Only occasionally should cleanings be carried out, paying particular attention to the removal of limescale from the area of the filtrate measuring vessel. Cleaning is an extremely simple operation, as all parts of the device that are in contact with the pulp are very easily accessible. Any cleaning water used can be immediately drained through a receiving vessel surrounding the water drain pipe.

Two preferred embodiments of the device according to the invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 shows a device for determining pulp stock permeability with a vertically reversible drainage tube , around a horizontal axis. The following describes the best embodiments of the invention. Figures 1 and 2 show a part of the pulp line 1, from which a continuous partial flow is taken from the pulp stock up to the branch line 2, which is adjustable by means of a valve 3, which is suitably an orifice slide valve.

The point of intake depends on where in the production process the desirability of the pulp must be determined. All that matters for the intake is that the pulp line 1 is a continuous flow line, where the pulp stock is under pump pressure. The mass can then be the so-called at the vat consistency, i.e. its consistency is 2.5 ... 5.5% of the absolute dry mass. The pulp line can be a direct transport line in the production process or also a collection line, along which the pulp is taken from the bottom of the cone by means of a pump and led back from the top to the cone, i.e. to the pulp tank.

The continuous partial flow of the pulp stock separated along the branch line 2 is fed from below to the overflow box 4, which has a constant overflow level defined by the overflow edge 5. The continuous overflow is fed back to the process via return line 6.

Referring now to Figure 1, there will be shown an embodiment of a measuring device shown therein.

A short downcomer 8 is mounted on the oblique bottom 7 of the overflow box 4 6 70085 forming the pulp feed section of the measuring device. The position of this downcomer 8 is chosen so that the pulp entering the overflow box 4 flows continuously past the inlet of the downcomer to prevent deposits. The downcomer 8 is under the constant inlet flow pressure of the surface height of the mass in the overflow box 4 adjusted by the overflow edge 5.

Below the downcomer 8 is the actual measuring device, which is placed inside the receiving tank 9. Connected to the conical lower part of the tank 9 is a return line 11, which, as shown in the example, is led together with the return line 6 of the overflow box 4 in order to be able to return all the mass from the measuring device back to the process.

The core piece of the device for determining the permeability is a dewatering pipe 12 provided at its lower end with a wire base 13 and at its upper end with a funnel-shaped extension 14 to facilitate the entry of the pulp. On the side of the drain pipe 12 there is a smaller overflow pipe 15 which determines the surface height up to which the drain pipe is filled for measurement. Such an overflow pipe has proved to be expedient, since filling the pipe 12 up to its upper edge would cause considerable splashing of the mass.

Approximately halfway, the drain pipe 12 is attached to the end of a horizontal, rotatably mounted shaft 16. At one end of the shaft 16 is a counterweight 17 attached to a lever arm. By rotating the shaft 16, the drain pipe 12 can be pivoted vertically.

The horizontal axis 16, in turn, is fixed in its central region to the upper end of the vertical axis 18, which axis forms the center of rotation for the horizontal transistor circular motion of the drain pipe. The vertical shaft 18 can be rotated at a constant angular speed by means of a motor 19 and a reduction gear 20. The motor 19 and the gear 20 are supported inside the receiving tank 9 by a holder 21 which is suitably fastened to the inside of the receiving tank by means of fastening means (not shown).

On the circular path along which the dewatering pipe 12 moves about the vertical axis 18, both the downcomer 8 of the overflow box 4 and the rinsing device 22 are placed above the dewatering pipe.

II

the flushing device consists of a suitable flushing nozzle 23 connected to the water supply, which can be actuated by means of an automatically controlled water valve 24.

7 70085

Below the drain pipe 12 there is a filtrate receiving trough 25 of a certain inclination extending over a certain arc of the circular path, which is provided at its lower end with an outlet pipe 26. The outlet pipe 26 descends into a measuring vessel 27. 11. An air bubble tube 30 protrudes from above into the measuring vessel 27, to which measuring air can be supplied from the measuring air line 31. The measuring air line is further connected to a measuring and processing device 32 including a pressure transducer, e.g.

The measuring tube 12 itself can be rotated 360 ° about the horizontal axis 16 in its vertical plane during its horizontal circumferential movement. This pivoting movement is effected by means of mechanical actuators (not shown in more detail) which engage during the circular path movement, of which only the control curve 34 at the edge of the receiving tank 9 is shown as a hint.

The permeability of the pulp sample is determined as follows:

During its smooth circular movement, the measuring tube 12 enters a pulp stock 8 connected to the overflow box 4 at a certain time, from which a pulp stream flows continuously, which is fed to the receiving tank 9 and through the return line 11 to the process. The amount of mass coming from the downcomer 8 is so large that as it moves under the pipe 8, the dewatering or measuring pipe 12 must at least reach the height of its overflow pipe 15. The overflow pipe 15 leads off too much filling. As soon as the dewatering pipe 12 is filled with the pulp sample, the filtrate begins to drain out through the wire bottom 13 of the dewatering pipe. This initial filtrate is received by the receiving tank 9 and also by the return line 14.

After a certain accumulation angle of the vertical axis 18, which, measured from the first mass filling, corresponds to a constant pre-filtration, the dewatering tube 12 moves with its wire bottom 13 over the filtrate receiving trough 25. During a certain part of the circular path of the dewatering pipe 12, which due to the constant angular velocity corresponds to a precisely defined measurement time, the filtrate 8 70085 now flowing through the wire bottom 13 is collected in the filtrate now closed. The surface height of the filtrate entering the measuring vessel 27 is measured after the water outlet pipe 12 has moved away from the end of the filtrate receiving trough 25, bubbling by the pipe 30, and this measured value, which is a measure of the mass mass 33.

After the level measurement has taken place, the measuring vessel 27 is emptied by means of an automatic emptying valve 28. As the dewatering tube 12 moves forward in its circular path inside the receiving vessel 9, it is rotated 180 ° about a horizontal axis 16 so that the remaining pulp stock can drain from the dewatering tube into the receiving vessel 9.

During the rotation, the drain pipe then moves up the wire bottom 13 under a flushing device 22 which is actuated by automatic control of the valve 24 to flush out any pulp cake still attached to the wire bottom 13 and to finally clean the dewatering pipe. The tube is then turned back to its vertical position and a new measurement period can begin.

The means for controlling the program of the described operation are not shown in detail in the drawings and will not be described in detail, since such program functions can be accessed with known control devices.

Although the embodiment of the device shown in Fig. 1 is continuously adapted to the mass flow coming out of the overflow box 8 of the overflow box 4, a suitable closing member could be placed in the downcomer 8, which is closed for at least a certain circular movement of the drain pipe to avoid excessive pulping.

However, such a closing member of the downcomer 8 is necessary in the embodiment of Figure 2, although a vertically reversible but otherwise stationary drainage pipe is also used.

As can be seen from Fig. 2, there is a shut-off flap 35 placed between the oblique bottom 7 of the overflow box 7 and the downcomer 8. In order to avoid the accumulation of mass next to the closed flap, from which water would slowly drain during the closed time and thus

II

70085 could clog the downcomer, it is appropriate to place the closure flap very close to the bottom of the overflow box. On the other hand, the downcomer 8 must also be kept very short, so that when the flap is closed and in the resulting pressure equalization event, no pulp residues remain in the pipe under the flap. To avoid this, it is suitable to provide an air gap in the downcomer. It is essential that the shut-off flap used closes tightly so that during the folding operation, in which case in this embodiment the dewatering pipe 12 remains below the downcomer 8, more pulp or filtrate can enter the dewatering pipe.

Since there is no translational rotation of the dewatering tube in the embodiment of Fig. 2, the receiving vessel 39 is made substantially smaller. In the side walls of this vessel 39, a drainage tube 12 is mounted for pivoting about a horizontal axis 36 which can be rotated directly by the motor 37. However, the operation here does not take place smoothly, but is adapted to the rhythm required by the measurement method.

Since the rinsing of the dewatering pipe 12 in this embodiment cannot take place in an angle turned by 180 °, where the wire bottom 13 would be located below the downcomer 8, it takes place at a turning angle of the dewatering pipe 12 which is slightly 180 ° smaller. The rinsing nozzle 40 of the rinsing device 22 is also correspondingly positioned laterally from the downcomer 8 to the pivot plane of the drainage pipe 12.

Finally, in this embodiment, the filtrate receiving funnel 38 is replaced by the filtrate receiving chute 25.

The determination of compliance in this embodiment takes place mainly as explained in connection with Figure 1. Here, however, the predetermined rotation time and the infiltration time are not determined by the predetermined rotation angle of the dewatering pipe moving in a constant speed orbit, but by the opening and closing time of the drain valve 28 of the measuring vessel 27 and the rotational movement times of the dewatering pipe 12.

To fill the drain pipe 12 with a sample, the shut-off flap 35 of the drain pipe 8 is opened until the mass filling level in the drain pipe 12 is guaranteed to reach the height of the overflow pipe 15 through which the excess mass flows out. Then, within a predetermined time during which the drain valve of the measuring vessel 27 is open, the filtrate is allowed to run off. Immediately thereafter, the measurement time 10 70085 begins with the closure of the drain valve 28 of the measuring vessel 27 and ends at the time when the wire bottom 13 of the dewatering tube 12 is turned off the top of the filtrate receiving hopper 38 to bring it under the rinsing nozzle 40 to clean the dewatering tube. After cleaning, the drain pipe is turned back to its vertical position, at which point a new measuring cycle can begin.

Although Figures 1 and 2 show only schematically the structure of two embodiments of an apparatus for automatically determining the permeability of pulp pulp, it can be seen that all parts of the apparatus that come into contact with the pulp or water are extremely accessible for cleaning and that the devices are virtually non-existent. wire susceptible components.

Il

Claims (5)

1. Apparatus for repeated automatic determination of the dewaterability of a fiber suspension with a device for supplying the fiber suspension, closed on one side by a wire bottom and open at the opposite loading end, about a horizontal axis in a vertical pane swiveling water tank, drive mechanism can be moved with the loading end upright under the fiber suspension feed device and with the wire bottom directed downwards over a filter capture device for catching and measuring a filtrate flowing through the wire bottom and, furthermore, with the wire bottom, which is substantially upright underneath, the pivot shaft (36) of the drainage vessel (12) is arranged stationary, that the outlet pipe (8) of the supply device (4, 8) for the fiber suspension and the filter capture device (38) is arranged on a vertical line which passes through the pivot point of the drainage vessel (12). , that the inlet opening (40) a the flushing device is arranged on the side of the outlet pipe (8) in the pivot plane of the drainage vessel (12) and that the drive mechanism (37) is configured as a rotational drive (12) acting on the horizontal pivot shaft (12) with which the drainage vessel (12) the rate can be pivoted with the filling end (14) under the tap tube (8) and simultaneously with its wire bottom (13) over the filtrate catching device (38) or with its wire bottom (13) under the flushing water outlet opening (40). Device according to claim 1, characterized in that the pivot point of the drainage vessel (12) lies approximately in the middle of the vessel. Device according to claim 1, characterized in that the drainage vessel (12) below its filling opening (14) is provided with a substantially oblique downwardly directed overflow pipe (15). 4. Apparatus according to any of claims 1-3, characterized in that the dewatering vessel (12) for the fiber suspension having about 3.5-5.5% atro density has a length of about 400-1000 mm and a diameter of 50-150 mm. . 5. Apparatus for repeated automatic determination of the dewaterability of a fiber suspension with a device for supplying the fiber suspension, closed on one side by a wire bottom