CO2-100 Carbon Dioxide Gas-Sensing Electrode

Overview

The CO2-100 is an advanced gas-sensing electrode specifically designed for measuring dissolved carbon dioxide (CO2) in water. This sensor is essential for applications where CO2 levels significantly impact product quality, organism health, or process efficiency, including aquaculture, beverage production, biogas plants, and pharmaceutical manufacturing.

Key Features

• Gas-Sensing Technology: Measures dissolved CO2 directly in water
• Wide Range: Measures from 0.5 to 5,000 mg/L (ppm)
• Dual Output Options: Supports both RS485 Modbus RTU and 4-20mA current output
• Fast Response: Results within 90 seconds
• Automatic Temperature Compensation: Integrated PT1000 sensor for accurate readings
• Direct Connection: Connect directly to computer or PLC without additional instrumentation
• High Protection: IP68 waterproof rating ensures reliable operation

Applications

• Aquaculture and fish farming
• Shrimp and crustacean farming
• Beverage carbonation monitoring
• Brewery fermentation control
• Wine production
• Soft drink manufacturing
• Biogas production monitoring
• Anaerobic digestion processes
• Pharmaceutical fermentation
• Cell culture and bioreactors
• Water treatment plants
• Swimming pool water quality

Technical Specifications

The CO2-100 delivers precise dissolved CO2 measurements from 0.5 to 5,000 mg/L with automatic temperature compensation via the integrated PT1000 sensor. The gas-sensing membrane selectively detects CO2 molecules that diffuse across the membrane, providing accurate measurements independent of other dissolved gases.

Understanding Dissolved CO2

Carbon dioxide in water is important for several reasons:

Aquaculture

• Fish Health: Elevated CO2 (>20 mg/L) can stress fish and reduce oxygen uptake
• pH Impact: CO2 forms carbonic acid, lowering pH
• Water Quality: Indicator of organic load and respiration rates

Beverage Industry

• Carbonation Levels: Critical for product consistency and taste
• Fermentation Monitoring: Tracking CO2 production during brewing
• Quality Control: Ensuring proper carbonation in finished products

Bioprocessing

• Fermentation Control: Monitoring microbial activity
• Cell Culture: Maintaining optimal CO2 for cell growth
• Process Optimization: Maximizing productivity

pH and Temperature Effects

CO2 solubility is affected by:

• Temperature: Higher temperature reduces CO2 solubility
• Pressure: Higher pressure increases CO2 solubility
• pH: CO2 affects water pH and exists in equilibrium with bicarbonate and carbonate

The CO2-100’s automatic temperature compensation ensures accurate measurements across varying conditions.

Connectivity and Integration

With its RS485 Modbus RTU interface, the CO2-100 seamlessly integrates into modern SCADA systems and IoT networks. The 4-20mA current output option ensures compatibility with traditional industrial controllers and data acquisition systems.

Installation and Maintenance

The CO2-100 requires regular calibration and membrane replacement for optimal performance. The gas-permeable membrane must be kept clean and free from fouling. The robust IP68-rated construction allows for continuous immersion in aquaculture, beverage, and bioprocess systems.

Typical CO2 Levels

• Natural freshwater: 0.5-2 mg/L
• Aquaculture (safe): < 10-15 mg/L
• Aquaculture (stress level): > 20 mg/L
• Carbonated beverages: 3,000-4,000 mg/L
• Beer: 4,500-5,000 mg/L