News

  • Development of BOD detection

    Biochemical oxygen demand (BOD) is one of the important indicators to measure the ability of organic matter in water to be biochemically degraded by microorganisms, and is also a key indicator to evaluate the self-purification capacity of water and environmental conditions. With the acceleration ...
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  • Development of chemical oxygen demand (COD) detection

    Chemical oxygen demand is also called chemical oxygen demand (chemical oxygen demand), referred to as COD. It is the use of chemical oxidants (such as potassium permanganate) to oxidize and decompose oxidizable substances in water (such as organic matter, nitrite, ferrous salt, sulfide, etc.), an...
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  • Determination of residual chlorine/total chlorine by DPD spectrophotometry

    Determination of residual chlorine/total chlorine by DPD spectrophotometry

    Chlorine disinfectant is a commonly used disinfectant and is widely used in the disinfection process of tap water, swimming pools, tableware, etc. However, chlorine-containing disinfectants will produce a variety of by-products during disinfection, so the safety of water quality after chlorinatio...
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  • Introduction to DPD colorimetry

    DPD spectrophotometry is the standard method for detecting free residual chlorine and total residual chlorine in China’s national standard “Water Quality Vocabulary and Analytical Methods” GB11898-89, jointly developed by the American Public Health Association, the American Wate...
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  • The relationship between COD and BOD

    The relationship between COD and BOD

    Speaking of COD and BOD In professional terms COD stands for Chemical Oxygen Demand. Chemical Oxygen Demand is an important water quality pollution indicator, used to indicate the amount of reducing substances (mainly organic matter) in the water. The measurement of COD is calculated by using str...
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  • Water quality COD determination method-rapid digestion spectrophotometry

    Water quality COD determination method-rapid digestion spectrophotometry

    The chemical oxygen demand (COD) measurement method, whether it is the reflux method, the rapid method or the photometric method, uses potassium dichromate as the oxidant, silver sulfate as the catalyst, and mercury sulfate as the masking agent for chloride ions. Under the acidic conditions of su...
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  • How to make COD testing more accurate?

    How to make COD testing more accurate?

    Control of COD analysis conditions in sewage treatment ​ 1. Key factor—representativeness of the sample ​ Since the water samples monitored in domestic sewage treatment are extremely uneven, the key to obtaining accurate COD monitoring results is that the sampling must be representative. To achie...
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  • Turbidity in surface water

    What is the turbidity? Turbidity refers to the degree of obstruction of a solution to the passage of light, which includes the scattering of light by suspended matter and the absorption of light by solute molecules. Turbidity is a parameter that describes the number of suspended particles in a li...
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  • What is residual chlorine in water and how to detect it?

    The concept of residual chlorine Residual chlorine is the amount of available chlorine remaining in the water after the water has been chlorinated and disinfected. This part of chlorine is added during the water treatment process to kill bacteria, microorganisms, organic matter and inorganic matt...
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  • Lianhua Technology’s water quality analyzer shines with splendor at the IE Expo China 2024

    Lianhua Technology’s water quality analyzer shines with splendor at the IE Expo China 2024

    Preface ​ On April 18, the 25th China Environmental Expo opened grandly at the Shanghai New International Expo Center. As a domestic brand that has been deeply involved in the field of water quality testing for 42 years, Lianhua Technology made a wonderful appearance...
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  • Fluorescence dissolved oxygen meter method and principle introduction

    Fluorescence dissolved oxygen meter method and principle introduction

    Fluorescence dissolved oxygen meter is an instrument used to measure the concentration of dissolved oxygen in water. Dissolved oxygen is one of the important parameters in water bodies. It has an important impact on the survival and reproduction of aquatic organisms. It is also one of the import...
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  • UV oil meter method and principle introduction

    UV oil meter method and principle introduction

    The UV oil detector uses n-hexane as the extraction agent and complies with the requirements of the new national standard “HJ970-2018 Determination of Water Quality Petroleum by Ultraviolet Spectrophotometry”. working principle Under the condition of pH ≤ 2, the oil substances in the...
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