Handheld Water COD, Ammonia Nitrogen, Total Phosphorus and Total Nitrogen Meter

I. Product Overview

This product is a handheld COD, ammonia nitrogen, total phosphorus and total nitrogen four-parameter water quality testing system, designed for simultaneous, comprehensive on-site assessment of the core pollution indicators. The system comprises a handheld main unit with an integrated intelligent multi-channel detection module that switches between the four parameters with one key, and a multi-purpose accessory case housing a 6-position digester that supports the digestion pre-treatment required for COD, total phosphorus and total nitrogen. This integrated design enables a complete profile of organic pollution (COD), nitrogen forms (ammonia nitrogen, total nitrogen) and phosphorus pollution (total phosphorus) to be obtained on a single platform at sites with a power supply — a powerful tool for comprehensive diagnosis and supervision of complex water quality.

II. Applicable Standards

HJ 535-2009 《Water quality — Determination of ammonia nitrogen — Nessler's reagent spectrophotometric method》
HJ 536-2009 《Water quality — Determination of ammonia nitrogen — Salicylic acid spectrophotometric method》
HJ/T 399-2007 《Water quality — Determination of chemical oxygen demand — Rapid digestion spectrophotometric method》
GB 11893-89 《Water quality — Determination of total phosphorus — Ammonium molybdate spectrophotometric method》

III. Measuring Principle

The instrument strictly follows the national standard spectrophotometric principles and uses mature, reliable methods for each of the four parameters. COD: potassium dichromate high-temperature digestion spectrophotometry. Total phosphorus and total nitrogen: both require high-temperature potassium persulfate oxidative digestion; total phosphorus is then determined by ammonium molybdate spectrophotometry and total nitrogen by chromotropic acid disodium spectrophotometry. Ammonia nitrogen: Nessler's reagent or salicylic acid spectrophotometry. The instrument measures the absorbance of each reaction product at its characteristic wavelength and calculates the concentration from the stored standard curve according to the Lambert-Beer law.

IV. Applications

Industrial wastewater: influent, process units and outfall monitoring at wastewater treatment stations in electroplating, printing and dyeing, pharmaceutical and food processing plants.
Municipal sewage: influent, biological units, effluent and reuse water inspection at wastewater treatment plants.
Environmental water bodies: rivers, lakes, reservoirs and wetlands, groundwater monitoring wells and private water sources — routine monitoring and pollution screening.
Drinking water safety: drinking water source protection areas, backup sources and rural centralised water supply facilities.
Enforcement and emergency response: surprise sampling at enterprise outfalls, park outfall patrols, on-site screening of sudden water pollution incidents and pollution plume tracking.
Research and teaching: water quality research, process optimisation and on-site testing and data collection for teaching experiments.

V. Key Features

1. Android-based operating system with an elegant, user-friendly interface.

2. 4.3-inch HD touch screen with visual graphical pages, greatly improving operating efficiency.

3. High-reliability imported LED light source requiring no warm-up and offering long-term stability.

4. 10 mm × 10 mm large-area photocell for high sensitivity and a low detection limit.

5. 16 GB internal memory for more than 10,000 records; an optional Bluetooth printer allows results to be printed on site.

6. Wi-Fi and Bluetooth, plus a USB port for direct high-speed batch upload to a PC.

7. Water-resistant housing; the measuring chamber resists ingress of 0.5 mL of liquid.

8. Standard USB-C 5 V 2.1 A with BC 2.1 charging protocol support — compatible with third-party phone chargers, cables and power banks; intelligent lithium battery charge management allows long periods of mains-powered operation.

9. Bilingual Chinese/English operating system.

VI. Technical Parameters