RU2664922C1 - Reagent flow dosing and monitoring device - Google Patents

Abstract

FIELD: measuring equipment; monitoring devices.SUBSTANCE: device for dosing and monitoring the flow of reagents is intended for dispensing liquid reagents at concentrating factories of non-ferrous metal industry, as well as in other industries. Device comprises a pressure vessel equipped with a reagent lower and upper level sensor, inlet and outlet valves, a relay controller, a computing device, and an output valve control module. When the device is operating, the reagent level in the pressure vessel varies within the upper and lower levels set by the level sensor. Device operates automatically with a period T. In this case, the change in the volume of the reagent in the pressure vessel increases or decreases by the volume V. With the inlet valve closed, the average flow rate Qof reagent, which is determined by the value of the average level of the reagent in the pressure vessel during the inlet valve closed state time t, is determined by the relation Q=V/t. Average value of the outlet flow rate of the reagent for the inlet valve opened state time t, is also equal to V/tin view of the fact that the average value of the reagent level in the pressure vessel remains constant throughout the entire operation cycle of the device. Reagent consumption Qis set by the control module of the control outlet valve.EFFECT: ensuring the function of dosing a given flow rate of the reagent and monitoring the established average outlet flow rate of the reagent.1 cl, 2 dwg

Description

The present invention relates to the field of automation of production processes, in particular to devices for dispensing liquid reagents into the flotation process in processing plants.

A device for dispensing flotation reagents [1], comprising a reagent flow meter, a pressure tank equipped with shut-off floats and valves for reagent outlet and a microcontroller. The disadvantage of the device [1] is its complexity.

A device [2] is known for measuring the dosage of liquid reagents, containing a measuring vessel, inside of which a piston moves, inlet and outlet switching valves and a control device. The disadvantage of the device [2] is the pulsed nature of the supply of reagent at its output and the complexity of the device due to the presence of the movable part - the piston and 4 shut-off valves.

The prototype of the proposed device is a device [2].

The aim of the invention is to achieve reliable operation of the device, simplifying the design of the device and high metering accuracy. This is achieved by the fact that the vessel of the proposed device is equipped with a sensor of the upper and lower levels of the reagent, and the volume V _{about the} reagent in the vessel, set by the sensor of two levels, is maintained constant by means of a relay controller introduced into the proposed device. The output of the relay controller is connected to the control input of the input valve and to the computing device, and a control valve is connected to the output pipe of the vessel.

In Fig. 1 shows the proposed device, which depicts:

1 - pressure vessel

2. - reagent,

3 - sensor of two levels of reagent,

4 - relay controller

5 - input shut-off valve,

6 - output control valve,

7 - control module,

8 is a computing device,

9 - inlet pipe

10 - output pipeline

11 - throttle nipple,

N _in - the upper level of the reagent,

N _n - the lower level of the reagent,

Q _I - input reagent consumption,

Q _o - the output flow rate of the reagent,

N _cf - the average value of the height of the pressure of the reagent,

V _about - measuring volume

The proposed device operates as follows.

For definiteness, we assume that a reagent flows out of the outlet valve and the level in the pressure vessel decreases to the lower level of N _n . In this case, the signal from the lower level H _{n is} supplied to the relay controller 4, from the output of which a control signal is input to the input of the input shut-off valve 5. The reagent level in the tank rises to the upper H _at the reagent level, the control signal at the input valve is reset and the input valve closes, and the outflow of reagent 2 from the outlet valve 6 continues, and after a time ts of the closed state of the inlet valve 5, the level of reagent 2 reaches the lower level N _n. reagent. Output flow Q _out. The proposed device is installed by changing the control device 7 of the conditional passage of the output control valve 6. The dosing process is then cyclically repeated.

The throttle nipple 11 provides air pressure in the pressure vessel equal to atmospheric pressure. In Fig. 2 shows the cyclogram of the device on which are indicated: H _cf - the average value of the reagent level in the pressure vessel, t _o is the open time of the inlet shut-off valve 5, t _s is the closed time of the inlet shut-off valve 5, T is the cycle time of the proposed device.

During time t _{s the} measuring volume V _o concluded between the levels N _in and N _{n of the} reagent in the pressure vessel 1, flows from the outlet valve 6, therefore, the average flow rate Q _out. reagent for the time t3 is determined by the expression:

During the time to the open state of the inlet shut-off valve 5, the reagent level in the pressure vessel increases from N _n to HB by the value of V _about due to the input flow rate Q _in . reagent, which is greater than the output flow Q _o .

The average value of the output flow Q _O reagent. during the open state of the input shut-off valve 5 corresponds to the expression:

because the average value of N _cp reagent level during the open state to the shut-off valve 5 is equal to H _cf. as a time t _of the closed state of the shut-off valve 5.

The control signal of the shut-off valve 5 is fed to the input of the computing device 8, in which the output flow of the reagent Q _o is calculated _. in accordance with formula (1) and the input flow rate of the reagent Q _in during the time to the open state of the inlet shut-off valve 5 according to the formula (2). The value of Vo is set according to the signals of the sensor 3 when the reagent 2 reaches the upper H _in and lower H _n levels.

Thus, the proposed device performs the dosing of the reagent, performs the function of direct measurement of the output and input flow of the reagent. New features of the proposed device for dispensing and controlling the flow of reagents allow automatic calibration of the device, objective diagnostics of the device and the use of both linear and non-linear control valves at its output.

Literature

1. RF patent 2473050, G01F 11/00, B.I. No. 1, 01/20/2013.

2 .. RF patent 2337326, BI No. 30, 10.27.2008.

Claims (1)

A device for dispensing and controlling the flow of reagents, containing a pressure vessel, inlet and outlet valves, characterized in that the pressure vessel is equipped with a sensor of two levels of reagent, between which a predetermined volume V _o of the reagent discharged from the pressure vessel during the time (t _h ) of the closed shut-off state is formed valve, and a relay controller, to the input of which a sensor of two levels of reagent in the pressure vessel is connected, and the output of the relay controller is connected to the control input of the shut-off input valve and to the input of the an integral device receiving the durations of the times of the valve’s closed state (t _h ) and open state (t _o ) in each cycle T of the exhaust set of a given volume V _o ; regulating outlet valve is formed, to its control input is connected the control module defining a reactant flow Q output _O, the average output current reactant flow rate from the pressure vessel is calculated by the formula Q = V _{O on} / t _s; control of the reagent duct, the degree of clogging of the route before feeding into the pressure vessel is determined by the change in time t _about and t _s .

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