S157-P

Dissolved CO2 (DCO2) systems are designed to measure dissolved pCO2 in water at atmospheric pressure. The system consists of a DCO2 sampler with accessories, a non-dispersive infrared CO2 analyzer with built-in air pump, a data interface and software. The fast response DCO2 system consists of an IRGA flowing through a fast DCO2 sampling system, a liquid pump, a built-in gas pump, a data interface and software.

The S157 CO2 analyzer uses an infrared gas analyzer IRGA, which only measures gas phase CO2.It is part of the dissolved CO2 system (DCO2) because the system allows the CO2 gas to diffuse out of water and then the CO2 level in the gas phase is measured by the S157 analyzer.

DCO2 samplers are a key component of standard systems that collect pCO2 from liquids and deliver them to IRGA.The DCO2 sampler is covered with PTFE (Polytetrafluoroethylene) film that can be immersed in water (up to 2 feet).The carbon dioxide gas dissolved in water diffuses into the sampler through the polytetrafluoroethylene film and is transported to the carbon dioxide analyzer in a closed-loop fixed-voltage gas stream for testing.

Depending on the sampler, there are two types of DCO2 systems.

Probe type:Using probes inserted into the liquid, it is necessary to properly stir the liquid so that the carbon dioxide gas in the liquid diffuses into the gas stream through the sampling probe.The airflow is delivered to the detector by an internal air pump and circulates in a closed loop in the system.The carbon dioxide gas will continue to diffuse into the probe and the gas stream until equilibrium is reached.

Fast DCO2 system:There is no probe, but the liquid circulates through the sampling system, in which water flows in one direction and gas flows in the other direction (in the closed circuit), and now CO2 gas diffuses into the gas stream through the silicon tube of the DCO2 sampling system, andPass the detector

A fast-responsive DCO2 system is also available with circulation design.It uses a DCO2 sampling system, where water circulates through the silicon tube, and the gas channel on the other side of the silicon tube is the opposite.The CO2 gas then diffuses from water to the gas stream through the tubular tubes and is transported to the CO2 sensor for measurement.

The polytetrafluoroethylene film is permeable to gas at atmospheric pressure, but is impermeable to water.The system detects the dissolved partial pressure of carbon dioxide in water and is not sensitive to carbonate.Note that the determination of CO2 partial pressure is not based on pH measurement.The DCO2 system can be configured in a variety of ranges from ppm to 100% gas phase CO2 concentrations.

DCO2 sampling system

Note that the response time of the standard system is very slow (4-10 minutes) due to diffusion on the PTFE film.The response time depends on the liquid flow through the DCO2 sampler, so the solution must be well stirred.The response time of the through-flow fast DCO2 system is 2 to 4 minutes.

characteristic

•Measure the dissolved carbon dioxide in freshwater and seawater

•Customized to the desired pCO2 range (ppm to 100%)

•Based on the diffusion of carbon dioxide in liquids

• Based on infrared gas analysis

•Insensitive to carbonate

•Not based on pH measurement

application

• Ocean acidification research

•Fermentation Research

•Algae culture (bioreactor)

•Aquaculture

•Environmental monitoring

• Wastewater management

•Food and Beverage Industry

•Aquatic animal respiration assay (rapid response system)

Fast DCO2 sampling system

Quick responseD co2Application of system in the respiration assay of small goldfish

From the standardD co2System sample data