Geotextile Test Machine

Cement free calcium oxide rapid measuring instrument is the main index to measure the quality of cement and the thermal system of clinker calcination. The calcium oxide rapid measuring instrument adopts the direct titration method of glycol extraction benzoic acid. Under specific conditions, it takes 3 minutes to quickly and accurately determine the free calcium oxide content. 

It can be used in production control of cement plant, building materials, scientific research units, teaching buildings of colleges and universities, etc.

Technical Parameters:

Accuracy	the standard deviation is 0.046%
Extraction time	3 min
Power supply voltage	220 V, 50 Hz
Motor	stepless speed regulation
Power	450W
Time	1-99 minutes
Average heating rate	60 ℃ / min

Working Principle:

After ethylene glycol reacts with free calcium oxide in cement clinker, the conductivity of the solution is proportional to the content of free calcium oxide. The content of free calcium oxide in cement clinker is indirectly reflected by the measurement of conductivity. The instrument needs to be calibrated to achieve the purpose of accurate measurement.

The reaction of organic solution glycol with free calcium oxide in cement clinker at high temperature was studied:

（CH2OH）2+CaO→（CH2O）2Ca+H2O

The calcium glycol formed by the above reaction is dissociated in glycol according to the following formula:

（CH2O）2Ca→（CH2O）22-Ca+Ca2+

Ethylene glycol and calcium ions conduct electricity in solution, and the degree of conductivity is related to the content of free calcium oxide. The content of free calcium oxide in cement clinker can be indirectly measured by measuring the conductivity of solution.

In the use of the instrument, the cleanliness of the electrode has a great influence on the accuracy of the measurement results. Therefore, the conductive electrode should be kept clean during the use of the instrument.