Method for rapidly determining dissolved oxygen in water

Abstract

The invention discloses a method for rapidly determining dissolved oxygen in water. The method is characterized by using a water sampler, a test tube or colorimetric tube, reagents, a dropper and a dissolved oxygen reference card, wherein the water sampler comprises a soft bottle with a rubber stopper; the rubber stopper is provided with an air tube and a water tube; the air tube and the water tube are respectively provided with a valve card; the reagents include anhydrous manganese sulfate and alkaline potassium iodide; and the dissolved oxygen reference card is a standard color gradation card made according to the colors of the precipitates produced by reaction between the standard water sample containing different dissolved oxygen and the reagents. The method comprises the following steps: 1. taking a water sample; 2. fixing the water sample; and 3. determining the dissolved oxygen value of the water sample through colorimetry. The method has the following characteristics: the oxygen in the air can be avoided from being dissolved in the water sample by using the water sampler for acquiring water samples; and the color of the flocculent precipitate generated by the water sample is directly compared with the dissolved oxygen reference card and the method is simple, fast and applicable, the dissolved oxygen is measured immediately by using the method and the result is obtained within 3-5 minutes, so the method has site guidance significance.

Description

technical field [0001] The invention belongs to a method for measuring dissolved oxygen, in particular to a method for quickly measuring dissolved oxygen in water. Background technique [0002] Dissolved oxygen is the basis for fish survival and is closely related to fish growth and reproduction. If dissolved oxygen is sufficient in water, fish will grow normally, but if dissolved oxygen in water is insufficient, fish will not grow even if fish have sufficient bait and are at the optimum growth temperature. , poor disease and stress resistance, if no technical measures to increase oxygen are taken, the fish will float, or even die in the pond, causing serious economic losses to aquaculture production. [0003] Dissolved oxygen measurement is a key link in pond dissolved oxygen management and improvement of breeding benefits. At present, the dissolved oxygen measurement only stays in the laboratory and cannot be widely applied in the production site. There are two technical ...

AI Technical Summary

Problems solved by technology

At present, the dissolved oxygen measurement only stays in the laboratory and cannot be widely applied in the production site. There are two technical difficulties: one is that there is no special water collector suitable for the site, and it is difficult to avoid the dissolution of oxygen in the air during the sampling operation. In water, it will affect the judgment of the result; the second is that it cannot be measured in time, and it can be used immediately after measurement

However, laboratory determination of standard solutions must be calibrated every day, and professionals are required to calibrate and titrate, which is difficult for producers to master. In addition, the laboratory measurement time is too long, and it is difficult to guide production.

There is a relevant rapid detection method found in production, but it does not include a special method or step for collecting water samples to avoid oxygen in the air from dissolving into water. The measured dissolved oxygen value is not the true value of the water sample, and it is difficult to guide production.

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