Shenchanghong DIS-1D Portable Digital COD Digestion Analyzer
| Brand | Shenchanghong |
|---|---|
| Origin | Guangdong, China |
| Manufacturer Type | Direct Manufacturer |
| Region | Domestic (China) |
| Model | DIS-1D |
| Digestion Method | Rapid Digestion |
| Heating Module | Single Aluminum Block Heater |
| Batch Capacity | 4 samples |
| Temperature Range | Ambient to 170 °C |
| Temperature Accuracy | ±1.0 °C at 170 °C |
| Digestion Vessel Volume | 60 mL |
| Timing Accuracy | ±0.1 s/hour |
| Heating Rate | Reaches setpoint in ≤15 min |
| Timer Range | 1–9999 min |
| Power Supply | AC 220 V ±10 %, 50 Hz / DC via cigarette lighter or battery (optional adapter) |
| Rated Power | 500 W |
| Dimensions | 105 × 160 × 90 mm |
| Weight | ~2.0 kg |
| Housing Material | Corrosion-Resistant Coated Aluminum Alloy |
| Safety Protection | Dual-stage thermal cutoff (auto-shutdown at ≥185 °C) |
| Vessel Compatibility | Four φ16 mm borosilicate glass tubes (imported, thermal shock-resistant) |
Overview
The Shenchanghong DIS-1D Portable Digital COD Digestion Analyzer is a compact, field-deployable thermal digestion system engineered for precise, reproducible oxidation of organic and inorganic analytes in aqueous matrices. It operates on the principle of closed-vessel, temperature-controlled wet chemical digestion—specifically optimized for standard methods requiring strong acid oxidation under elevated thermal conditions, including ISO 6060 (COD), ISO 15681-1 (total phosphorus), ISO 11905-1 (total nitrogen), and ISO 11083 (total chromium). Unlike conventional open-reflux systems, the DIS-1D employs a single high-thermal-conductivity aluminum heating block with integrated PID feedback control to maintain stable setpoint temperatures from ambient up to 170 °C. Its lightweight, low-profile architecture (105 × 160 × 90 mm; ~2.0 kg) and dual-power capability—supporting AC mains, automotive 12 V DC, and external battery packs—enable seamless deployment in mobile laboratories, wastewater treatment plant perimeters, riverbank monitoring stations, and emergency response scenarios where grid power is unavailable.
Key Features
- Single-block rapid-heating system achieving target temperature in ≤15 minutes, minimizing turnaround time between digestion cycles.
- Precision temperature regulation with ±1.0 °C accuracy at 170 °C, validated across the full operating range using NIST-traceable reference thermometers.
- Multi-point linearization calibration protocol compensates for inherent thermistor nonlinearity—eliminating systematic offset errors common in low-cost digital digesters.
- Dual-stage thermal safety architecture: primary PID control loop + independent hardware-based cutoff at 185 °C, preventing overheating and ensuring compliance with IEC 61010-1 safety requirements for laboratory equipment.
- Corrosion-resistant anodized aluminum housing with sealed electronics compartment—rated IP54 for dust and splash resistance in humid or chemically aggressive environments.
- Optimized thermal insulation design reduces standby power consumption by >30% compared to unshielded block heaters while maintaining uniform inter-vessel temperature deviation <±0.8 °C (n=4, 170 °C).
- Timer resolution of 0.1 s/hour drift supports long-duration protocols (up to 9999 min) required for low-COD or refractory matrix digestion per ASTM D1252-12 (Method B).
Sample Compatibility & Compliance
The DIS-1D accommodates four standard φ16 mm borosilicate glass digestion tubes (60 mL nominal volume), compatible with Hach, Lovibond, and EPA-compliant tube geometries. Tube material meets DIN ISO 3585 specifications for hydrolytic class HGB 1, ensuring resistance to concentrated sulfuric/nitric/phosphoric acid mixtures at 170 °C. The instrument supports method-defined digestion protocols aligned with ISO/IEC 17025-accredited environmental testing laboratories. While the unit itself does not carry CE or UKCA marking, its electrical design conforms to IEC 61010-1:2010 Edition 3 for measurement/control laboratory equipment. For GLP/GMP workflows, users may integrate the DIS-1D into validated digestion workflows with documented calibration records, maintenance logs, and traceable temperature verification using external Class A platinum RTDs.
Software & Data Management
The DIS-1D operates via embedded microcontroller firmware with no proprietary software dependency. All parameters—including temperature setpoint, digestion duration, and real-time block temperature—are configured and monitored through a tactile membrane keypad and dual-line LCD display with backlight. Time-stamped operation logs (start time, setpoint, actual block temperature every 30 s, end time) are retained in non-volatile memory for up to 500 cycles and can be manually exported via RS-232 serial interface (optional cable) for audit trail generation. While the device lacks native network connectivity, it is fully compatible with LIMS integration when paired with third-party data acquisition modules supporting Modbus RTU or ASCII command protocols. All timing and thermal functions comply with FDA 21 CFR Part 11 requirements when used within a validated procedural framework that includes operator authentication, electronic signature logging, and audit trail review controls.
Applications
- Routine COD determination in municipal wastewater influent/effluent per ISO 6060 and EPA 410.4.
- Total phosphorus quantification in surface water and agricultural runoff using ascorbic acid/molybdate colorimetry (ISO 15681-1).
- Total nitrogen analysis via alkaline persulfate oxidation (ISO 11905-1) in drinking water source monitoring.
- Hexavalent and total chromium speciation support through controlled acidic digestion prior to AAS or ICP-MS analysis (ISO 11083).
- Field validation of online COD sensors and process analyzers in industrial effluent streams.
- Educational use in university environmental chemistry labs for method comparison studies (e.g., dichromate vs. permanganate oxidation efficiency).
FAQ
Can the DIS-1D be used for EPA Method 410.4 without modification?
Yes—the instrument’s temperature stability, timer resolution, and 4-tube capacity align with the thermal profile and batch requirements of EPA 410.4. Users must supply EPA-compliant digestion tubes and reagents.
Is calibration traceable to national standards?
The unit supports user-performed calibration using NIST-traceable reference thermometers; factory calibration certificates are available upon request with optional third-party verification.
What power sources are supported in field mode?
AC 220 V ±10 %, 12 V DC via vehicle cigarette lighter socket (with included adapter), or external 12 V LiFePO₄ battery packs (not supplied).
Does the instrument meet ISO/IEC 17025 documentation requirements?
It provides all necessary operational data for inclusion in method validation packages; full compliance depends on lab-specific SOPs for calibration, maintenance, and record retention.
Are replacement digestion tubes available through Shenchanghong?
Yes—original φ16 mm borosilicate tubes (Cat. No. SCT-16-60) are supplied with full thermal shock certification and lot-specific QC reports.
