The dissolved oxygen meter is an instrument to measure the content of oxygen dissolved in the aqueous solution. Oxygen is dissolved in water by surrounding air, air movement and photosynthesis. It can be used to measure and monitor processes where oxygen content affects reaction speed, process efficiency, or the environment.
Dissolved oxygen refers to the amount of oxygen dissolved in water, usually recorded as DO, expressed in milligrams of oxygen per liter (in mg/L or ppm). Some organic compounds undergo biodegradation under the action of aerobic bacteria, which consumes dissolved oxygen in the water. If the dissolved oxygen cannot be replenished in time, the anaerobic bacteria in the water will multiply quickly, causing the water body to become black and smelly. The amount of dissolved oxygen in water is an indicator to measure the self-purification ability of the water body. The dissolved oxygen in the water is consumed, and it takes a short time to return to the initial state, indicating that the water body has strong self-purification ability, or that the water body pollution is not serious. Otherwise, it means that the water body is seriously polluted, and the self-purification ability is weak, or even the self-purification ability is lost.
Dissolved oxygen meters have been widely used, mainly including the following fields:
1. Aquaculture:
To ensure the respiratory demand of water products, real-time monitoring of oxygen content, automatic alarm, automatic oxygenation and other functions.
2. Water quality monitoring of natural waters:
Detect the pollution degree and self-purification ability of the water area to prevent biological pollution such as eutrophication of the water body.
3. Sewage treatment, control indicators:
Anaerobic tank, aerobic tank, and aeration tank are combined with other indicators to control the water treatment effect.
4. Control the corrosion of metal materials in industrial water supply pipelines:
Generally, sensors are used to control the pipeline to achieve zero oxygen to prevent rust. It is often used in power plants and boiler equipment.
Dissolved oxygen meters are divided into desktop dissolved oxygen meters, portable dissolved oxygen meters and pen-type dissolved oxygen meters according to their portability. The pen-type dissolved oxygen meter has a small measurement range and is a special and convenient instrument; the desktop and portable dissolved oxygen meters have a relatively wide measurement range. The difference is that the portable dissolved oxygen meter uses a DC power supply and can be carried to the site more conveniently.
According to the purpose, it is divided into laboratory dissolved oxygen meter and industrial online dissolved oxygen meter. Dissolved oxygen meters used in laboratories have a wide measurement range, multiple functions, and high measurement accuracy; industrial dissolved oxygen meters are characterized by good stability, reliable operation, certain measurement accuracy, strong environmental adaptability, and strong anti-interference ability, with analog flow output, digital communication, upper and lower limit alarm and control functions.
