SU874666A1 - Device for automatic control of precipitate level in waste water purification units - Google Patents

Description

one

The invention relates to wastewater treatment, and more specifically to devices for automatically controlling the level of sludge in the wastewater treatment plant.

A device for automatically regulating the level of sludge in wastewater treatment plants, consisting of a sensor and a measuring transducer 1, is known.

The accepted design and circuitry of the known device has unsatisfactory metrological and operational indicators, which is caused by the incompatibility of these solutions with the technology of wastewater treatment in full, in particular, in terms of sensitivity, inertia and time between failures.

Closest to the present invention is a device for automatically adjusting the level of sewage treatment in sewage treatment plants, comprising a photoelectric sensor connected in series with the electronic unit and control unit 2.

The disadvantages of the known device include a significant level control error

sediment (up to + 20-25%) relative to the set mark and lack of reliability in the time between failures (no more than 3000 hours), due to the influence of water color and unregulated elements of the optical and electrical circuits of the device.

The purpose of the invention is to increase the control accuracy and reliability of the device as a whole.

This goal is achieved by the fact that, in the device, the photoelectric sensor is equipped with an optical corrector of water color, and the electronic unit controls the intensity of light emission and a bridge converter for outputting a photoelectric sensor with a balance controller connected to the photoelectric sensor, a starting regulator with a tuning unit the start-up time and the zero-signal controller connected to the bridge transducer of the output signal of the photoelectric sensor.

FIG. 1 is a block diagram of the device according to the invention; FIG. 2 shows a photoelectric sensor 30 design.

The device contains a photoelectric sensor 1 connected in series with the electronic unit 2 and the start-controlling unit 3 (Fig. 1). The electronic unit 2 is provided with interconnected regulator 4 of the light intensity, bridge converter 5 of the output signal of the sensor 1 and with regulator 6 ba- lence , the start-up regulator 7 with the start-up time setting node 8, the executive node 9, the signaling unit 10, the voltage regulator 11 and control elements 12, as well as the scale regulator 13, the zero signal regulator 14, showing m microammeter 15 with pointer 16 control limits.

The photoelectric sensor 1 is equipped with an optical corrector 17 for water color and a light emitter 18, a light source 19 with a cartridge 20 placed in respective housings 21 and 22 with protective glasses 23, gaskets 24, a lid 25, sealing rings 26 and a nut 27. Case 21 and 22 are connected by a metal pipe 28, in the upper part of which there is a stuffing box 29, consisting of a nut 30, a washer 31, a gasket 32, a ring 33 and intended to fix and seal the connecting cable 34.

To prevent contamination of the gland entry 29 and adjusting the immersion depth of the sensor 1, a sectional metal pipe 35 is installed, which is connected with a nut 36 and a gasket 37.

The device works as follows.

J Sewage water in a mixture with sludge enters through a central pipe 38 into a sewage disposal plant, for example, a sump 39, where sedimentation occurs (Fig. 1). The sediment is removed by means of sludge pumps (scrapers) 40, connected by metal pipes 41 to a farm 42 driven by an electric motor 43.

The level of sediment relative to a predetermined mark is monitored by sensor 1. When immersing sensor 1 in a sediment, the intensity of the light emitted to receiver 18 decreases due to an increase in the optical controlled medium (Figs. 1 and 2). This leads to a decrease in the output signal of sensor 1 and the appearance of an imbalance signal in the bridge converter 5. The unbalance signal enters the starting regulator 7 in which the starting time of the actuating node 9 is tuned using node 8 taking into account possible ingress of large particles of sediment between receiver 18 and source light emission. The operation of the node 9 leads to the activation of the node 10 of the alarm and the control and regulating node 3, which, in turn, causes the operation of the electric motor 44 and the opening of the valve 45 on the pipeline 46, which drains the sediment from the structure 39. The wastewater after settling is discharged into the circular groove 47.

When the level of sediment drops below a predetermined level and the optical density of the monitored medium decreases, the valve 45 closes the device in reverse order.

The corrector 17 produces a deviation of the device's operation from the chromaticity of the waste water p v. Si, and adjustments 4, 6, 13 and 14, as well as a pointer 16, setting the device according to sensitivity and range of sludge level control.

The protective glasses 23 are hydrophobicized in order to minimize the extent of their coating with sediment.

Introduction to the photoelectric sensor of the device for the optical corrector of water chromaticity, and to the electronic block the device for interrelated light intensity control, a bridge output converter of the sensor with a balance regulator, a start regulator. With a start time setting unit and a zero signal regulator provides a significant increase in control accuracy and reliability in the operation of the device and, as a consequence, an increase in the productivity of wastewater treatment plants

0 water under production conditions.

Claims (2)

1. Popkovich G.S. Fundamentals of automation and automation of plumbing and sewage facilities. M., Higher School, 1975, p. 295-302. 2. Shimkovich V.V. Devices for automatic control of the parameters of wastewater in sewage treatment plants of the oil refining industry. M., TsNIIE Tneftekhim 1978, p.28-29.