Handheld Water Total Nitrogen Meter

I. Product Overview

The handheld total nitrogen system is designed for fast, on-site determination of total nitrogen in water. It consists of a handheld main unit and an accessory case containing a 6-position digester. The main unit combines an optical channel dedicated to total nitrogen with a smart operating system, while the separate digester converts the nitrogen compounds in the sample into a measurable form. This split design gives the flexibility to complete the whole workflow — from sample pre-treatment to accurate concentration measurement — on site.

II. Measuring Principle

The meter uses alkaline potassium persulfate digestion combined with chromotropic acid spectrophotometry. The water sample is first digested at high temperature in an alkaline medium with potassium persulfate in the accessory-case digester, oxidising all forms of organic and inorganic nitrogen to nitrate. After digestion the nitrate reacts with chromotropic acid disodium salt under specific conditions to form a stable yellow complex. The handheld main unit measures the absorbance of the yellow solution at a characteristic wavelength (for example 420 nm) and applies the Lambert-Beer law with its built-in standard curve to calculate the total nitrogen concentration.

III. Applications

Monitoring the performance of biological nitrogen removal, optimising carbon source dosing and ensuring compliant total nitrogen in the effluent of municipal and industrial wastewater treatment plants; routine eutrophication assessment and early warning for rivers, lakes and reservoirs; enforcement checks and emergency monitoring of outfalls by environmental agencies; and rapid analysis in research, aquaculture water management and similar applications.

IV. Key Features

1. Android operating system with an elegant interface and user-friendly operation.

2. 4.3-inch high-definition touch screen combined with a visual graphical interface that greatly improves operating efficiency.

3. High-reliability imported LED light source: no warm-up required and stable long-term performance.

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

5. 16 GB internal memory stores more than 10,000 records; an optional Bluetooth printer prints results on site.

6. Wi-Fi and Bluetooth connectivity plus a USB port for fast batch upload of data to a PC.

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

8. Standard USB-C 5 V 2.1 A input with BC 2.1 charging protocol support: compatible with third-party phone chargers, cables and power banks, with intelligent lithium-battery charge management for continuous mains operation.

9. Bilingual Chinese / English operating system.

V. Technical Parameters