Water quality total nitrogen analyzer

TN-2500Water quality total nitrogen analyzerIt adopts the latest international standards（ISO 20236:2024）A rapid analytical instrument for measuring total nitrogen in water quality has been launched, which overcomes the drawbacks of traditional national standard methods in environmental water quality analysis, such as long analysis time, high requirements for analytical reagents, and multiple interference factors. The instrument has a compact structure and high degree of automation.

Method principle:

The sample undergoes catalytic oxidation and combustion at high temperatures, converting nitrogen compounds (including organic nitrogen, ammonia, nitrate, nitrite, etc.) in water into nitrogen oxides, which are detected by chemiluminescenceCLDPerform technical analysis on its concentration and ultimately calculate the total nitrogen content.

Method Standard：

The applicable standards areISO 20236:2024This standard is developed by the International Organization for Standardization（ISO）In the2024year11Monthly release, detailed regulations on the determination of summary nitrogen by high-temperature catalytic oxidation combustion method（TN）The method.

Scope of application：

Applicable water sample types: including drinking water, raw water, groundwater, surface water, seawater, wastewater, and leachate, etc

Main technical performance indicators:

1Measuring range:0～1000 mg/L (scalable)

2Measurement lower limit:0.5mg/L

3Measurement error:±0.2mg/L (0～10mg/LWithin the measurement range)

<= 5%(greater than10mg/Ltime)

4Analysis time: shortest4 minute

5Dilution method:1~50Multiple arbitrary dilutions

6Temperature control of oxidation furnace: ±5°C （720°CWhen setting the temperature

7Injection method: syringe automatic injection

8Carrier gas: compressed air, supply pressure: >=0.2MPa

Technical advantages:

Automated analysis: The standard adopts automated programs to improve detection efficiency and accuracy.

Anti interference capability: It can handle samples containing volatile organic compounds (such as industrial wastewater) and provide differential method guidance to eliminate interference.

Comparison with other methods:

1Compared to traditional methods such as UV spectrophotometry that require digestion and reagent reactions, the oxidation combustion method directly decomposes samples at high temperatures, avoiding the influence of factors such as reagent purity and digestion conditions, and simplifying the operation process. During the entire process analysis, no reagents are used.

2Due to the use of thermal decomposition+Chemiluminescence method（CLD）It has the advantages of strong oxidation ability, no interference from salt, metal ions, turbidity, chromaticity, short measurement time, and no secondary pollution.

3National standardHJ 6362012Other methods such as alkaline potassium persulfate digestion UV spectrophotometry rely on chemical oxidation steps, which may introduce more sources of error.

TN-2500Water quality total nitrogen analyzeradopted720°CCatalytic combustion oxidation method, the sample is injected into a combustion tube filled with oxidation catalyst through a syringe and heated to720°CBurn and oxidize the total nitrogen in the sample to decompose it into nitric oxide. The combustion products are transported by carrier gas and introduced into chemiluminescence detection（CLD）In the system, NODetected.CLDcheck outNOPeak area of content, converted through data processing,Due to the peak area and the presence ofTNThe concentration is directly proportional, obtained by measuring with a standard solution of a certain concentration beforehandTNThe relationship between concentration and peak area in the sampleTNThe concentration can be detected.