Water plays an irreplaceable role in human production and life. Whether for drinking, irrigation, or industrial manufacturing, the quality of water directly affects human health, ecological balance, and the normal operation of production activities. The importance of water analysis as a key means of ensuring water quality safety and quality is self-evident. At the same time, with the development of technology, various advanced water analysis instruments have emerged, providing strong support for accurate and efficient water analysis work.
1、 The Importance of Water Analysis
（1） Ensuring human health
The safety of drinking water is directly related to human life and health. Through water analysis, harmful substances such as pathogenic microorganisms, heavy metals (such as lead, mercury, cadmium, etc.), and organic pollutants (such as pesticide residues, polycyclic aromatic hydrocarbons) can be detected in water. If the microorganisms in the water exceed the standard, it may cause intestinal diseases, infectious diseases, etc; Excessive intake of heavy metals can cause serious damage to the human nervous and digestive systems. For example, long-term consumption of water with excessive lead content can lead to delayed intellectual development in children and anemia, kidney dysfunction, and other problems in adults. Only through rigorous water analysis can we ensure that drinking water meets safety standards and safeguard people’s physical health.
（2） Maintain ecological balance
Water is an important component of ecosystems, and the water quality of rivers, lakes, oceans, and other bodies of water has a profound impact on ecological balance. Water analysis can monitor indicators such as dissolved oxygen, pH, chemical oxygen demand (COD), and biochemical oxygen demand (BOD) in water. Low dissolved oxygen content can lead to the death of aquatic organisms due to hypoxia; Imbalance in acidity and alkalinity can affect the living environment and reproductive capacity of aquatic organisms; If the chemical oxygen demand and biochemical oxygen demand are too high, it indicates that there is too much organic matter in the water body, which can easily lead to eutrophication of the water body, causing a large number of algae to reproduce and disrupting the balance of the aquatic ecosystem. Through water analysis, timely understanding of water quality changes and taking corresponding governance measures can help maintain the stability and health of ecosystems.
（3） Assist in industrial production
In the industrial field, water is widely used in cooling, washing, boiler water and other processes, and different industrial production processes have strict requirements for water quality. For example, in the manufacturing process of electronic chips, extremely high requirements are placed on the particle and ion content in water, and even trace amounts of impurities may affect the performance and quality of the chip; If the hardness of the boiler water exceeds the standard, scale will form on the inner wall of the boiler, reducing the heat conduction efficiency and even causing safety accidents such as boiler explosions. Through water analysis, monitoring and regulating water quality according to different production needs can improve product quality, reduce equipment failure rates, save energy, and ensure efficient and stable operation of industrial production.
（4） Support water resource management
With the increasingly severe problem of water scarcity, rational development, utilization, and protection of water resources have become the top priority. Water analysis can provide accurate data support for water resource management, helping to understand the distribution, quality status, and changing trends of water resources. By analyzing different regions and types of water bodies, develop scientific plans for water resource protection and development, and achieve sustainable utilization of water resources. For example, in water resource allocation projects, real-time monitoring and analysis of water quality in water source and receiving areas are carried out to ensure the quality and safety of water allocation and improve the efficiency of water resource utilization.
2、 Common water analysis instruments
（1） PH meter
A pH meter is an instrument used to measure the acidity or alkalinity of a solution, which determines the pH value by measuring the activity of hydrogen ions in the solution. The pH meter mainly consists of electrodes (including glass electrodes and reference electrodes), measurement circuits, and display devices. In water analysis, pH meters are widely used for monitoring the acidity and alkalinity of drinking water, industrial wastewater, surface water, etc. For example, in sewage treatment plants, it is necessary to monitor the pH value of sewage in real time in order to adjust the treatment process and ensure that the effluent pH value meets the discharge standards; In chemical production, controlling the pH value of the reaction solution is crucial for product quality and reaction efficiency.
（2） Conductivity meter
Conductivity meter is used to measure the conductivity of aqueous solutions, reflecting the total concentration or salt content of ions in water. Various ions in water, such as sodium ions, chloride ions, calcium ions, etc., have conductivity. The higher the conductivity of a solution, the higher the ion concentration. Conductivity meters usually consist of two parts: conductivity electrodes and measuring instruments. In the pharmaceutical industry, conductivity meters are commonly used to detect the purity of purified water and injection water; In boiler water treatment, the salt content in the water is controlled by monitoring the conductivity of the water to prevent scaling.
（3） Dissolved oxygen analyzer
Dissolved oxygen analyzer is used to measure the content of dissolved oxygen in water. It works based on the principles of electrochemistry or fluorescence. The electrochemical dissolved oxygen analyzer mainly consists of a dissolved oxygen electrode and a measuring instrument. Through the chemical reaction between the oxygen electrode and dissolved oxygen in water, a current is generated, and the magnitude of the current is proportional to the dissolved oxygen content; The fluorescence method dissolved oxygen analyzer uses the response of fluorescent substances to dissolved oxygen to measure the concentration of dissolved oxygen. In aquaculture, dissolved oxygen analyzer is an important equipment to ensure the survival of fish. Aquaculture personnel can add oxygen in a timely manner based on the measurement results to prevent fish from dying due to hypoxia; The control of dissolved oxygen plays a crucial role in the effectiveness of biological treatment processes in wastewater treatment.
（4） Turbidity meter
Turbidity meter is used to measure the turbidity of water and reflect the content of suspended particles in the water. Suspended particles in water, such as sediment, colloids, microorganisms, etc., can cause scattering and absorption of light. Turbidity meters determine the turbidity of water by measuring the scattering or transmission intensity of light. Turbidity meter is an important monitoring device in drinking water treatment, and the turbidity of drinking water directly affects the sensory characteristics and disinfection effect of the water; In monitoring water bodies such as rivers and lakes, changes in turbidity can reflect the pollution status and soil erosion of the water body.
（5） Chemical Oxygen Demand (COD) Analyzer
COD analyzer is used to determine the chemical oxygen demand in water, which is an important indicator for measuring the content of organic pollutants in water. The working principle of COD analyzer mainly includes potassium dichromate method, potassium permanganate method, rapid digestion spectrophotometry method, etc. The potassium dichromate method is a classic COD determination method, which oxidizes organic matter in water under acidic conditions using potassium dichromate, and calculates the COD value based on the amount of potassium dichromate consumed; The rapid digestion spectrophotometric method utilizes the color change of the solution after a chemical reaction, and calculates the COD value by measuring the absorbance with a spectrophotometer. In industrial wastewater discharge monitoring, COD analyzer can timely detect the content of organic pollutants in wastewater and determine whether it meets the discharge standards; In sewage treatment plants, the effectiveness of treatment processes is evaluated by monitoring changes in COD.
（6） Biochemical Oxygen Demand (BOD) Analyzer
The BOD analyzer is used to determine the biochemical oxygen demand in water, reflecting the dissolved oxygen consumption by microorganisms decomposing organic matter in water. It is an important indicator for evaluating the degree of organic pollution and self purification capacity of water bodies. BOD analyzers mainly include dilution inoculation method, microbial membrane method, etc. The dilution inoculation method is to dilute the water sample, inoculate microorganisms, and cultivate it at a certain temperature for 5 days. The difference in dissolved oxygen before and after cultivation is measured to calculate the BOD value; The microbial membrane method utilizes the response of microbial sensors to organic matter in water to rapidly determine BOD. In environmental monitoring, BOD analyzer is commonly used for water quality evaluation of surface water, domestic sewage, etc., providing data basis for water pollution control.
Water analysis plays an irreplaceable and important role in safeguarding human health, maintaining ecological balance, assisting industrial production, and supporting water resource management. Common water analysis instruments, such as pH meters, conductivity meters, dissolved oxygen analyzers, etc., provide solid guarantees for efficient and accurate water analysis work with their unique functions and advantages. With the continuous advancement of technology, water analysis techniques and instruments will also continue to develop and improve, making greater contributions to the rational utilization and protection of water resources for humanity.