Regarding sewage treatment

TOC: Total Organic Carbon; COD: Chemical Oxygen Demand; BOD5: Biological Oxygen Demand over 5 days; DO: Dissolved Oxygen; NH3-N: Ammonia nitrogen; SS: Suspended solids

Thank you. I would like to ask what parameters are measured by TOC?

The ORP value (oxidation-reduction potential) is an important indicator of water quality. Although it cannot alone reflect the quality of water, it can, by taking into account other water quality indicators, give an indication of the ecological environment within an aquarium system. What is the redox potential? In water, every substance has its own unique redox properties. Simply put, we can understand it as follows: at the microscopic level, each different substance possesses a certain degree of oxidation-reduction capability, and these substances with varying oxidation-reduction properties can influence one another, ultimately resulting in a certain overall oxidation-reduction property. The so-called redox potential is used to reflect the macroscopic oxidizing-reducing properties of all substances in an aqueous solution. The higher the redox potential, the stronger the oxidizing power; the lower the potential, the weaker the oxidizing power. A positive potential indicates that the solution exhibits certain oxidizing properties, while a negative potential indicates that it exhibits reducing properties. Our filtration systems, aside from denitrification, are essentially oxidative biochemical filtration devices. For organic substances, microorganisms break down longer carbon chains through oxidation (or open various carbon rings), and through complex biochemical processes they ultimately oxidize organic carbon in its various forms into carbon dioxide ； At the same time, these oxidation reactions also break substances such as nitrogen, phosphorus, and sulfur from their respective carbon bonds, forming corresponding inorganic compounds. In the case of inorganic substances, microorganisms oxidize them from low-valent states to high-valent states through oxidation. This is the essence of oxidative biochemical filtration (here we are only concerned with those substances that are oxidized and broken down by microorganisms, rather than those that are absorbed and assimilated by them). It can be seen that, while biochemical filtration is taking place, the substances in the water are continuously oxidized. The process of biochemical oxidation is accompanied by the continuous formation of oxidation products; therefore, on a macroscopic scale, the redox potential continuously increases. Therefore, from this perspective, the higher the redox potential, the more thoroughly the pollutants in the water are filtered out.