Sonnen K06 Fully Automated Kjeldahl Nitrogen Determinator
| Brand | Sonnen |
|---|---|
| Origin | Shanghai, China |
| Model | K06 |
| Instrument Type | Kjeldahl Nitrogen Determinator |
| Automation Level | Fully Automated |
| Nitrogen Determination Range | 0.1–240 mg N (conventional nitrogen) |
| Sample Throughput | 3–7 min per sample |
| Repeatability | ≤0.5% RSD |
| Sample Weight Capacity | ≤6 g (solid), ≤25 mL (liquid) |
| Nitrogen Recovery Rate | ≥99.5% (100% ± 0.5%) |
| Power Consumption | 1800 W |
| Dimensions (L×W×H) | 460 × 450 × 720 mm |
| Linearity Range | RSD ≤1% for samples with nitrogen content within 1–3× nominal concentration |
| Titration Resolution | 0.1 µL/step |
| Internal Data Storage | 100,000 test records |
| User-Defined Methods | 500 presets |
| Cooling Water Flow Rate | 0.5 L/min (at 15 °C), 1.5 L/min (at 25 °C) |
| Safety Certifications | ISO 9001, CE |
Overview
The Sonnen K06 Fully Automated Kjeldahl Nitrogen Determinator is an engineered solution for precise, trace-level total nitrogen quantification in compliance with internationally recognized wet-chemistry reference methodology. Based on the classical Kjeldahl principle—acid digestion in concentrated sulfuric acid, alkaline steam distillation, boric acid trapping, and potentiometric or colorimetric titration—the K06 delivers metrologically traceable results across diverse matrices. Its design adheres to core principles of analytical rigor: controlled thermal decomposition, quantitative ammonia liberation under regulated steam flow, and high-fidelity endpoint detection. The instrument is validated against national standards including GB/T 22923–2008 and JJF 109–2012, and supports routine calibration verification, method validation, and audit-ready documentation required in GLP and GMP environments.
Key Features
- Fully automated reagent dosing, digestion monitoring (via external module), steam distillation, back-titration, waste drainage, system self-calibration, liquid level sensing, result calculation, report generation, and data export—eliminating manual intervention from start to finish.
- Multi-layered safety architecture: motorized 304 stainless steel reaction chamber with PTFE-coated safety door; real-time digestion tube presence detection; dual-mode water level monitoring (float + electrode) in steam generator; integrated pressure and temperature sensors with overpressure/overtemperature cut-off; continuous monitoring of distillate temperature and volume; dynamic cooling water flow control with low-flow alarm and automatic shutdown.
- Dual-mode steam generation with 0–100% adjustable steam flow rate, optimized for both standard and high-nitrogen samples—including those requiring extended distillation kinetics.
- External titration cell with LED-assisted illumination and 16-bit RGB digital color sensor for robust endpoint discrimination—minimizing ambient light interference and enabling adaptive color threshold calibration (auto/manual).
- High-precision titration system featuring a monolithic ceramic-plunger pump with PTFE diaphragm, delivering 0.1 µL/step resolution and long-term chemical resistance to strong acids and bases.
- Dynamic titration algorithm synchronizes titrant addition speed with real-time distillate generation rate—achieving true concurrent distillation–titration–calculation and reducing total cycle time by up to 40% versus fixed-rate systems.
- ARM-based multi-core embedded OS with 10-inch HD capacitive touchscreen, supporting bilingual (English/Chinese) UI and contextual operation guidance.
- Integrated diagnostics and one-touch system reset; programmable auto-self-check at power-on and before each run.
Sample Compatibility & Compliance
The K06 accommodates solid samples up to 6 g and liquid samples up to 25 mL, covering routine applications in food, feed, soil, fertilizer, environmental sludge, pharmaceutical excipients, and biological tissues. It achieves ≥99.5% nitrogen recovery across its full working range (0.1–240 mg N), verified using certified reference materials (CRMs) such as BCR® 279 (seaweed) and NIST SRM 8414 (Bovine Serum Albumin). Linearity is confirmed per ICH Q2(R2) guidelines: RSD ≤1% over a 1–3× span of target nitrogen concentration. The system complies with ISO 9001 quality management requirements and bears CE marking for conformity with EU Machinery and EMC directives. Optional modules support nitrate-nitrogen conversion and high-nitrogen (>240 mg N) analysis workflows.
Software & Data Management
Data integrity and regulatory readiness are ensured through built-in 21 CFR Part 11–compatible audit trail functionality, including timestamped user login/logout logs, method change history, raw titration curves, and parameter modification records. All results are stored internally (100,000 records) with optional network export via Ethernet or USB. Reports are exportable in 12 formats—including .docx, .xlsx, .pdf, and .csv—with customizable templates compliant with laboratory information management system (LIMS) ingestion protocols. Up to 500 user-defined analytical methods can be saved, each with independent settings for digestion time, alkali volume, steam ramp profile, titrant concentration, and endpoint sensitivity.
Applications
- Protein quantification in dairy, meat, cereals, and plant-based alternatives (using standard nitrogen-to-protein conversion factors).
- Crude protein and non-protein nitrogen (NPN) assessment in animal feed formulations and aquaculture diets.
- Total nitrogen profiling in agricultural soils, composts, and wastewater biosolids for nutrient balance modeling.
- Quality control of nitrogen-containing APIs and excipients under pharmaceutical GMP frameworks.
- Regulatory testing for fertilizer labeling compliance (e.g., ISO 5983-1, AOAC 984.13).
- Research-grade nitrogen budget studies in ecological and biogeochemical investigations.
FAQ
What digestion system is required for use with the K06?
The K06 is designed for integration with standalone or modular digestion units (not included). It accepts pre-digested samples in standard 250 mL or 400 mL Kjeldahl tubes and performs only distillation, titration, and calculation.
Does the K06 support direct nitrate-nitrogen determination?
Not natively—but an optional nitrate reduction module (requiring cadmium column or Devarda’s alloy pre-treatment) can be added to enable total oxidized nitrogen analysis per ISO 14256-2.
How is data security and user access managed?
The system supports role-based authentication (administrator, operator, reviewer) with password complexity enforcement and session timeout. All critical actions generate immutable entries in the electronic audit trail.
Is remote monitoring or control possible?
Yes—via secure HTTP/HTTPS interface compatible with enterprise IT infrastructure. Real-time status dashboards, alarm notifications, and historical query functions are accessible through standard web browsers.
What maintenance intervals are recommended?
Daily: visual inspection of tubing, reagent levels, and condenser cleanliness. Quarterly: calibration of color sensor and titration pump volumetric accuracy using certified standards. Annually: full performance qualification (PQ) per manufacturer SOP, including recovery, repeatability, and linearity verification.
