Shengaohua SH-24A/30A Touchscreen Intelligent COD Digestion System

Overview

The Shengaohua SH-24A/30A Touchscreen Intelligent COD Digestion System is a precision-engineered benchtop digestion unit designed for standardized chemical oxygen demand (COD) analysis in accordance with ISO 6060, APHA Standard Methods 5220D (Closed Reflux Colorimetric Method), and EPA Method 410.4. It employs a dual-zone resistive heating architecture to enable simultaneous, independent thermal control across two separate heating blocks—allowing concurrent digestion of samples requiring different temperature protocols (e.g., COD at 165 °C and total phosphorus at 123 °C). The system utilizes sealed digestion vials to prevent reagent loss and cross-contamination, ensuring high reproducibility and compliance with GLP laboratory practices. Its thermally stable aluminum heating blocks provide uniform heat distribution and rapid thermal response (<10 min to reach setpoint), minimizing inter-run variability and supporting high-throughput environmental testing workflows.

Key Features

• Dual independent heating zones with real-time temperature monitoring and PID-based feedback control
• 4.3-inch full-color capacitive touchscreen interface with intuitive icon-driven navigation and multilingual menu support (English default)
• Six pre-programmed digestion protocols stored onboard—including optimized curves for COD, total phosphorus, total nitrogen, copper, and hexavalent chromium
• Configurable timer range from 1 to 199 minutes, with programmable resolution of 1 minute and accuracy of ±1 min over full scale
• Over-temperature cut-off protection with automatic power disconnection when deviation exceeds ±5 °C from setpoint
• Corrosion-resistant, high-heat polymer housing rated for continuous operation at ambient temperatures up to 45 °C
• Optically transparent, borosilicate-reinforced protective lid enabling direct visual monitoring of digestion reactions without compromising safety or thermal integrity
• Modular 24-position (SH-24A) or 30-position (SH-30A) sample layout compatible with standard 15 mL digestion vials (e.g., Hach, Lovibond, or equivalent)

Sample Compatibility & Compliance

The SH-24A/30A accommodates standard 15 mL borosilicate glass or PTFE-lined digestion tubes used in accredited wastewater and surface water laboratories. Its dual-temperature capability supports parallel execution of multiple standard methods—including ISO 15681-1 (total phosphorus), ISO 11908 (total nitrogen), and ASTM D1253 (residual chlorine interference mitigation during COD digestion). The system meets mechanical safety requirements per IEC 61010-1:2010 and electromagnetic compatibility standards EN 61326-1:2013. While not certified under FDA 21 CFR Part 11, its audit-ready digital log (timestamped start/end times, temperature profiles, and user ID tagging) supports traceability in regulated environments operating under ISO/IEC 17025 quality management systems.

Software & Data Management

No external software installation is required—the embedded firmware provides complete local control, protocol storage, and event logging. All digestion cycles are automatically timestamped and recorded in non-volatile memory, including set temperature, actual block temperature (logged every 30 s), timer values, and user-triggered events (e.g., pause/resume). Data export is supported via USB 2.0 port (FAT32 formatted drive), generating CSV-formatted logs compatible with LIMS integration and statistical process control (SPC) platforms. Firmware updates are performed offline using signed binary files to maintain data integrity and system validation status.

Applications

This digestion system serves as a core preparation tool in municipal wastewater treatment plants, industrial effluent monitoring labs (pulp & paper, pharmaceuticals, textiles, food & beverage), and third-party environmental testing facilities. It is routinely deployed for routine compliance monitoring against discharge permits (e.g., EU Urban Wastewater Treatment Directive, US NPDES), method validation studies, QA/QC duplicate analysis, and proficiency testing programs. Its dual-zone design significantly reduces turnaround time when analyzing multi-parameter water matrices—such as combined COD/TP screening in lake sediment porewater or simultaneous heavy metal and organic load assessment in tannery effluents.

FAQ

What standards does the SH-24A/30A comply with for COD digestion?
It supports methodology alignment with ISO 6060, APHA 5220D, and EPA 410.4 through precise temperature control, sealed-vial operation, and validated heating profiles.
Can the preset digestion programs be customized and saved?
Yes—users may modify temperature setpoints, ramp rates, hold durations, and cooling delays, then save up to six custom protocols with alphanumeric naming.
Is the system suitable for use in humid or corrosive laboratory environments?
The housing is constructed from molded halogen-free flame-retardant polymer with IP32-rated ingress protection; the transparent lid features chemically tempered glass resistant to fuming sulfuric acid vapors.
What is the maximum safe operating altitude?
Rated for continuous operation up to 2,000 meters above sea level, with derated power output above 1,500 m to maintain thermal stability.
Does the unit include calibration documentation?
Each unit ships with a factory-verified temperature uniformity report (per block, at 123 °C and 165 °C), traceable to NIM-certified reference thermometers.