SU929218A2 - Apparatus for thickening hydraulic mixture in pressure pipelines - Google Patents

Description

(54) DEVICE FOR CONDENSION OF HYDROSMES IN HANDLING

TRUBSETROVODAKH

one

The invention relates to mountainous conditions and can be used to thicken the slurry transported in pressure pipelines.

According to the main author. St. N 622498 discloses a device for thickening slurry in pressure pipelines, a housing with a distribution mechanism NIZMSH4 and cavities filled with a granular material, a forward nozzle and a drain nozzle with valve 1.

During the drying of slurries with a predominant content of fine fractions and slime in the upper part of the body of this device above the granular layer, there is an accumulation of solid particles carried there by reversing filtration flow through the layer of granular material and gradually clogging the upper parts of the cavities of the device, reducing the efficiency of the device and requiring cleaning of the cavities by removing top cover of the corta. In addition, in the lumen, colonies can accumulate randomly.

items brought there (paper, rags, chips, etc.), clogging of the cavity and causing with time a partial loss of performance of the thickening device, which also requires periodic cleaning of the cavities and the granular layer to restore it (the device’s operation operation.

The purpose of the invention is to increase the condensation efficiency by preventing clogging of the upper part of the body.

The goal is achieved by the fact that the device is equipped with a flushing nozzle with a flap and an automatic control system for the self-cleaning process, which includes a pressure differential sensor with sensing elements installed in the lower parts of the housing cavities, an amplifier / two actuators and a hysteresis threshold element whose outputs are connected with drain valves and flush dampers through appropriate actuators, and the input is connected through an amplifier with a differential pressure sensor output and FIG. 1 shows a device dp thickening the slurry; in fig. 2 - distribution mechanism. The device for thickening the slurry in the pressure pipelines consists of a housing 1 with a lid 2 connected through. cut the transition pipe 3 to the upper part of the discharge pipe 4. Cortus 1 is divided by a partition 5 into two cavities 6 and 7 communicating with each other in the upper part of the body into which mesh shells 8 and 9 are inserted (only the retaining grids of shells are shown in Fig. 1 ), filled with granular material 1O, which is a granular filter - working medium. Cavities 6 and 7 communicate with the transition pipe 3 via a distribution mechanism in the form of a movable 11 and a fixed 12 disc with holes 13-16. The rotation of the movable disk 11 is carried out by the shaft 17 from the drive. Drain pipes 18 and 19 for drainage of the clarified flow communicate with openings 13 and 16 of the fixed disk 12 and are connected to the common drain pipe wire 2O through regulator 21 (damper or single weekly types). The flushing pipe 22 for draining into the receiving tank 23 during the flushing period accumulated over the granular layer of the slurry and other items (rags, chips, paper, etc.) is installed on the lid 2 of the housing 1 and communicates with cavities 6 and 7 through the notch 24 in the lid, and through the regulator 25 and the pipeline 26 - with the receiving tank. At the bottom of the housing 1, at the level of the retaining grids 8 and 9, sensing elements 27 and 28 are installed to measure the pressure at the beginning and end of the granular separation element 10 of the thickener along the outflow stream. The sensing elements 27 and 28 are connected to the inputs of the differential pressure sensor 29, the output of which is connected via an amplifier 30 of the differential pressure signal to the input of the hysteresis threshold element 31, which by its outputs is connected to the inputs of the corresponding actuators 32 and 33 of the regulating bodies 21 and 25 of the drain and flushing 22 nozzles. The proposed device works as follows. 92 84 The total cycle of the device operation consists of two cycles (periods) - the main and additional cycles, one of which periodically replaces the other. Differences in the operation of the cycles are observed only in giving the separated part of the slurry stream in the second cycle an additional function — the function of the flush flow and removal of the accumulated sludge above the granular layer of sludge to the receiving tank 23. In this connection, the first cycle (main) is the period of condensation and continuous adjustment of the consistency slurry in the pressure pipe 4; the second (optional) is the period of washing (self-cleaning) of the granular filter in the thickener body 1 and partial thickening and control of the consistency of the slurry in the pressure pipe 4. The operation of the device is switched from one cycle to another automatically by signal commands generated at the outputs a hysteresis threshold element 31 for the signal from the differential pressure sensor 29 amplified by the amplifier ZO. Thus, the slurry stream moving along the discharge pipe 4 at the point where the device is connected splits into a separated part of the stream (a discharge stream) and a main (condensed) transport stream. As a result of an abrupt change in the speed and trajectories of the jets, the inertial-gravitational forces acting on the particles of the solid phase are insufficient to hold all the particles in the main flow. Some part of the particles enters with the separated stream into the transition nozzle 3, in which the solid phase of the slurry is partially divided into large and small particles. The coarse particles of solid phase, the precipitate, are returned to the pressure pipeline, where they fall into the zone of action of the condensed slurry stream and are carried away by it. Small particles of the solid phase are transported by the separated flow of the slurry through the combined apertures 15 fixed 12 and movable 11 disks and grating 8 into the cavity 6 of the housing 1. At the same time, the solid phase, represented by small particles, is retained in the layer of granular material 10 and separated from the stream. The flow that has passed the suspended layer of granular material 1O in the cavity 6 above the leurek 5 in the device body 1 reverses its direction of movement and enters the cavity 7 of the body filled with the same granular material 1O as cavity 6. In cavity 7 the slurry stream is subjected forced downstream filtration, and fine particles that have penetrated into the suspended layer are grainy. During the upward filtration, the material is washed out, and carried away in a downward flow through the grid 9 and 13 from the movable 11 and the fixed 12 discs combined from the turn into the drain pipe 19, cleaning the granular material in this cavity. Next, the clarified part of the slurry stream through the pipe 18 and the drain pipe 20 enters the drain, or for use for certain technical purposes. The flow rate of the clarified flow is controlled by a damper 21 installed on the drain pipe, thereby controlling the consistency of the hydraulic system in the pressure pipe 4. Periodically turning the distribution mechanism in the form of a movable 11 and fixed 12 discs with openings 13-16 provides a periodic reversible direction of movement of the separated flow hydraulics in cavity 6 and body 1. The change in direction of movement of the separated slurry stream by the distribution mechanism in the cavity body is shown in phi year 1 and 2 solid and dotted arrows. The operation of the device after revision is similar to that described, with the only difference that the separated part of the slurry stream enters the cavity, 7, and the clarified part of the stream from cavity 6 through pipe 18 enters the drain pipe 20 to drain. With the passage of time during the passage of the separated part of the slurry stream through the cavity through the cavities 6 and 7, some of the slurry particles penetrate through the granular layer and exit into the upper part of the cavities above the layer. Due to expansion. the flow in the upper part of the housing 1 decreases the flow rate, resulting in an increase in the dynamic imbalance of the velocities of the solid and liquid phases, and not all sludge particles trapped in the upper part of the housing can penetrate back through the granular layer when the flow moves in cavities 6 and 7 down (with downstream filtration) into the drain pipes 18 and 19. Some of the particles are retained in the upper part of the body cavities, as a result of which they gradually accumulate, the cavities are stuffed and a sharp increase in pressure drop across the separation grain 18 ohm layer 10. The pressures at the beginning and end of the spacer member (layer) are sensed and the sensors 27 and 28 arrive at the differential pressure sensor 29 inputs, which is formed on Yz1hode signal proportional to the pressure difference across the separating element thickener. The signal from sensor 29, amplified by amplifier ZO, is fed to the input of hysteresis threshold element 31. When driving the upper part of body cavities to increase the pressure drop on the separating element above the set threshold value, a hysterosis threshold element 31 is triggered. an actuator 32 for closing the adjusting flap 21 of the drain pipe 20 and an actuator 33 for opening the adjusting flap 25 of the flushing pattern BCA 22. Thus, the first cycle is completed and begins a second cycle of the device. As the shutter 21 closes and the shutter 25 opens, the flushing (diversion) stream turns the distributor mechanism, alternately passes through both parts of the granular layer, carries the accumulated sludge particles from cavities 6 and 7 through the notch 24 in the lid 2 of the thickener housing to the flushing branch pipe 22, transporting them through conduit 26 back to the receiving tank 23. At the same time, the granular material in the cavities of the casing is cleaned, as a result of which the pressure drop across the separating granular layer is reduced and the signal level is also lowered proportional to the differential pressure at the outputs of the sensor 29 and the amplifier 30. Due to the hysteresis of the hysteresis threshold element 31, the valve 25 of the flushing pipe 22 is open, and the valve 21 of the drain pipe 2O is closed until the full Parts of the cavities and the differential is flushed will not decrease to the normal baseline value. When the overpressure drops on the granular layer below the set value of the hysteresis of the element 31, new signal commands are formed at its outputs that reverse the actuators 32 and 33: the first to open the valve 21 the second to close the drain valve 25

and flushing nozzles, respectively. After closing the backwash 25 of the flushing pipe 22, the actuator 32 is automatically connected to the system for controlling the consistency of the slurry in the pressure pipe 4 or to the system for optimizing the loading of the pipe 4 with a solid material (not shown). This completes the second cycle and again begins the first cycle of the device’s bots.

The time interval of the first cycle is 1O-15 times longer than the time interval of the second cycle at an SO-4O% hysteresis value of the threshold element 31 and for a given degree of slurry thickening is mainly determined by the initial composition and consistency of the hydraulic mixture in the pipeline in front of the device.

Hydraulic impact when reversing the direction of movement of the separated slurry stream is eliminated by selecting the diameters of the openings 13-16 of the movable 11 and the fixed 12 discs of the distribution mechanism such that during periodic rotation of the movable 11 disc there is no simultaneous complete overlap of the apertures, as well as selection of the number of revolutions.

Thus, with automatic self-cleaning of the thickener, the operational reliability is increased and the service life of the proposed device is prolonged while preserving its technological adjusting characteristics, which significantly increases the drying efficiency. And the stability of the adjustment characteristics of the device ensures the stability and quality of the system for optimizing the loading of hydraulic transport pipelines with solid material, in which the device is used as a regulating authority, which leads to a decrease in electric power consumption and operating costs for hydrotransport.

Claims (1)

Invention Formula A device for the dewatering of slurry in pressure pipelines by the author. St. No. 622498, characterized in that, in order to improve the condensation efficiency by preventing clogging of the upper part of the housing, the device is equipped with a flushing nozzle with a flap and an automatic control system for the self-cleaning process, including a pressure differential sensor with sensing elements installed in the lower parts of the housing cavities, an amplifier, two actuators and a hysteresis threshold element, the outputs of which are connected to the drain and flush valves through appropriate means olnitelnye mechanisms, and the input is connected through an amplifier to output a differential pressure sensor. Sources of information taken into account in the examination 1, USSR Author's Certificate No. 622498, cl. B 03 B 5/62, 1974.