SU579601A1 - Arrangement for controlling pulp level in vacuum filter - Google Patents

Description

with the primary inputs of the elements OR.- the second inputs of which are connected to the sensor of the lower level, and the output - with the regulating valves ..

This allows, when the pulp level leaves the control zone by deviation, to switch both groups of vacuum filter sections from parallel mode to sequential mode in accordance with a given program and, by reducing the flow rate ynps, further lower the level of nj-Jifc in the bath, and in the case of Minkal pulp flow and dropping of the level to the limiting level, completely shut off the stripping simultaneously with the S.ZE signal;

In the drawing is a representation of the function: the on-line diagram of the proposed device: Royce:;: vac.

The device contains a level control (deviation),. The output of which is connected to the actuator 2 mounted on the supply pipe 3, the intermediate level sensor 4 (for example, a limit switch connected to the float rod), the program control unit 5 whose outputs through the elements OR b, 7 affect the control valve 8 , 9, - installed on the impulse lines x 10, - 11 supply, valve 12, 13, stripping, installed on pressure pneumatic valves; these pipelines 14, 15, sensor, 16 lower level, connected to the indicator 17,

The drawing also shows schematically the vacuum filter 18 and the upper level sensor 19, the pulp levels in the bath of the quince vacuum filter corresponding to the boundaries of the control zone of the level 1 regulator:. As well as the lower level corresponding to the lower boundary of the working zone of the vacuum filter levels. Below level c, air may be poured into the suction pneumatic section (not shown in the drawing).

In the simplest case, a symmetric multivibrator with an adjustable pulse duration can be used as the software control unit 5.

The device works as follows.

Regulator 1 level through the executive body 2, installed on the supply pipe 3, in a known manner maintains the specified level of pulp in the zone is regulated, neither from a) to only if the flow of pulp through the feed pipe 3 is not less than its flow from the vacuum bath filter.

in the specified control zone, the actuator 2 changes the flow area of the pipeline 3 from the minimum (at level a) to the maximum (at level b) of ekachen,

In case of insufficient flow of pulp, the Level 1 regulator will not keep the set level intact, and the last one will begin: despite TOF, it will be open Lio.

LR level output k & zone regulation 03UHH5J a-3 and its further lower.-Pch; sensor 4 activates; :: 4: o; . level set by me.;: ukj: OWN AREA AND LOW; with ;; takes a block of software. :: ;;:. evil,; ::, The signal from block 5 is proggliv: ;; UO y:: expressions through the elements g,. 7;.; Og; (works on regulating: i ,, b,;. Ia; ibrfo open) valves 8, 9, „:; ..isha.pakpy on impulse lines x. .: Pngakgg and intended for pack, ,, ;;.: 3,) Akil valves 12, 13 Stripping pressure pneumatic pipe bridges 14; 15,

By means of valves 8, 9, both groups of vacuum filter sections are switched from parallel mode to sequential stripping mode in accordance with a predetermined program. When this occurs, the alternation of unloading of two groups of sections occurs, which prevents the further development; e of the level in the section for the reduction of the consumption of GEulpa,

At alp1; 1; ar4; Um.: M: -: inflow of pulp into Edi; Hy vacuum filter level, despite the measures taken, will be reduced and reaches its lower limit from, below which air can leak into the line , the sensor .16 П1; will trigger; the level, which through the elements OR b, - 7, will turn on the control loops 8, 9. At the same time, it blows off both sections of the vacuum filter, will simultaneously turn on the alarm 17, giving a signal about process mode.

With an increase in the flow of pulp into the bath of the Akum-filter 18 and an increase in the level of the sensor 16, the lower level will turn off the signaling device 17 and remove the ban on the vantilea 8, 9. At the same time, the program control channel from the sensor 4 of the intermediate stage will start.

With a further increase, the flow of the switch and the increase in the level will turn off. At the same time, the program control channel will be turned off. The de-energized valves 8, 9 will now be open without affecting the operation of the filter. 1 level regulator is activated, and the cycle of operation is shown by TODMTOH