What is the purpose of the reaction coil in the APA 6000 High Range Hardness and Alkalinity analyzers?
APA 6000 reaction coil
The reaction coil allows reproducible dispersion of the sample/indicator with the titrant (acid). As the two fluids disperse, a full range of concentrations result. This range begins with all sample/indicator then transitions to a greater concentration of titrant. Eventually, a maximum concentration of titrant is reached and as the transition continues, the titrant strength drops until only sample/indicator is present again. The reaction coil is placed between the valve and detector. After the dispersion described above occurs, the response is measured as fluids pass through the detector. The reaction coil is only needed in the High Range Hardness and Alkalinity because these two analyzers use titration methods while most other APA 6000s use colorimetric methods.