G. Steinle;

The organic load in the condensates and in the vapour from, the boilers was determined by the automatic analysis of the steam chamber by gas chromatography. Ethanol, acetaldehyde, acetic acid, methanol, formaldehyde and formic acid were found as main components. The content of ethanol, acetaldehyde and methanol in each condensate was determined.

It was found that the organic load is rising steadily from the condensate 1 till to the condensate 4 : ethanol from 2 to 50 mg/1, methanol from 19 to 106 mg/1 and acetaldehyde from 3 to 116 mg/1.

A significant difference was found in the content of ethanol, acetaldehyde and methanol in the juices and in the various syrups. The reason for it can be found in the use of formaldehyde during extraction, that leads to methanol formation, and in the alkaline degradation of sucrose in the boiling house forming acetaldehyde. The average content of methanol rose from 8 mg/1 in the thick juice to 54 mg/1 in the molasses. The content of acetaldehyde increased from 12 mg/1 in thin juice to 206 mg/1 in 2nd syrup and to 225 mg/1 in molasses.

Ethanol and acetaldehyde are formed during the anaerobic destruction of stored sugar beets. So it was tried to find a relation between this destruction, that is to say the constitution of the beet entering the factory, and the content of ethanol and acetaldehyde formed in the condensates and vapour from the boilers. These figures run more or less parallel to the conditions of storage and, in connection with it, to the destruction of the beets.

A quantitative gas chromatographic determination of the formaldehyde by using a thermal conductivity detector is foreseen.

 

Proceedings: CITS 1971
Page: 289–305

Language: GER

pdf download: CITS1971-289-305.pdf