RU2510021C2 - Method and device for continuous measurement of biochemical consumption of oxygen, biochemical demand for oxygen and speed of biochemical oxidation - Google Patents

Abstract

FIELD: instrument making.

SUBSTANCE: invention is designed for continuous measurement of biochemical oxygen consumption (BOC), biochemical oxygen demand (BOD) and speed of biochemical oxygen consumption in water medium (k1). Essentially a new method is proposed, as well as a device making it possible to continuously measure at the same time BOC, BOD and k1 both in running water (river, waste water header, etc.), and in a water reservoir. The method for continuous measurement of specified indices is characterised by the fact that a continuous flow of water taken for analysis is organised from a water object into a pipeline, besides, the speed of water flow in the pipeline is selected so that within the required period of time T (where T - duration of biochemical consumption) water passes the distance between two adjacent transits of the pipeline, where sensors are installed for continuous measurement of concentration of dissolved oxygen in running water. The device for realisation of this method consists in a water-intake module and a pipeline with non-transparent walls, on which in transits there are sensors of continuous measurement of concentration of dissolved oxygen, making it possible to keep monitoring of simultaneously three specified indices of water quality.

EFFECT: device improvement.

2 cl

Description

The invention relates to instrumentation and the theory of measurements and calculations and is intended for continuous measurement of biochemical oxygen consumption (BOD _t ), biochemical oxygen demand (BOD) and the rate of biochemical oxygen consumption in an aqueous medium (k ₁ ).

Analogues of the claimed invention, as far as we know, no. Only methods and devices for discrete measurements are known, and not BOD (needs), but only BOD _t , i.e. biochemical oxygen consumption over a time interval t, where the most applicable value of t is t = 5 days.

The aim of the claimed invention is to create unique, previously inaccessible opportunities for continuous monitoring of the three most important indicators of water quality: biochemical oxygen consumption, biochemical oxygen demand, rate of biochemical oxidation. Achieving this goal will allow timely detection of facts of an increase in the concentration of organic pollutants (pollutants) (for example, as a result of unauthorized releases of pollutants into a water body), as well as facts of a decrease in the rate of biochemical oxidation (for example, as a result of discharges of toxins that suppress the activity of aerobic microorganisms).

The specified goal is achieved by the fact that:

- a continuous water intake is organized with a constant flow of water from the studied site of the water body;

- the water sampled for analysis is passed through a constant section pipeline of length L meters;

- starting from zero gauge with an interval of ΔL meters, sensors for continuous measurement of dissolved oxygen concentration are installed in the pipeline;

- the flow velocity in the pipeline is selected in such a way that the time of passage of water between adjacent sections is of interest ΔT;

) биохимическое потребление кислорода за периоды времени ΔT, 2ΔT, …, $$\frac{L}{\Delta L}\Delta T$$

, также значения биохимической потребности и скорости окисления на моменты 0, ΔT, 2ΔT …, $$\frac{L}{\Delta L}\Delta T-1$$

.- the difference in oxygen concentrations in the zero (initial) and j-th sections (j = 1, 2, ..., $$\frac{L}{\Delta L}$$

) biochemical oxygen consumption over time periods ΔT, 2ΔT, ..., $$\frac{L}{\Delta L}\Delta T$$

, also the values of biochemical requirements and oxidation rates at moments 0, ΔT, 2ΔT ..., $$\frac{L}{\Delta L}\Delta T-\mathrm{one}$$

.

To compare the results of measuring the biochemical oxygen consumption by the UNI BPK device with the results of the classical (discrete) measurement, when the analyzed water sample is placed in a flask with a ground stopper and stored in the dark at a temperature of 20 ° С for a certain time t (for example, t = 5 days), the pipe walls of the UNI BPK device should be lightproof, and the device itself should be in a room with a constant temperature of 20 ° C.

Of particular interest to researchers will be the possibility of parallel measurement of water quality indicators: at a temperature of 20 ° C and at a real temperature of a water body. To do this, it is enough to install a second device directly immersed in a water body. Unlike the classical measurement (when a water sample is kept in a thermostat), there will be no need for additional conversion of the results to the temperature of the water body.

Method and device for continuous measurement of biochemical oxygen consumption, biochemical oxygen demand and biochemical oxidation rate, consisting of a water intake module and a pipe with opaque walls, on which sensors of continuous measurement of dissolved oxygen concentration are installed in certain sections, allowing monitoring of the three mentioned quality indicators simultaneously water that differs from existing methods and devices (oxygen meters / BOD testers) in that it allows t measure not only the biochemical oxygen demand of BOD, (where usually t = 5 days), but also the biochemical oxygen demand (BOD) and the rate of biochemical oxidation (k ₁ ), and do this not in a discrete, but continuous mode.

Claims (2)

1. The method of continuous measurement of biochemical oxygen consumption (BOD _T ), biochemical oxygen demand (BOD) and biochemical oxidation rate (k ₁ ), characterized in that they organize a continuous flow of water taken for analysis from a water body into the pipeline, and the water flow rate in the pipeline, they are selected so that for the required period of time T (where T is the duration of biochemical consumption), the water travels the distance between two adjacent sections of the pipeline in which sensors are installed for continuous measuring the concentration of dissolved oxygen in the flowing water. 2. The device for implementing the method according to claim 1, consisting of a water intake module and a pipe with opaque walls, on which sensors for continuous measurement of dissolved oxygen concentration are installed in the sections defined in claim 1, which allow monitoring of the three mentioned water quality indicators simultaneously.