APPENDIX B. 



BROWN COAL AND WOOD CHAR IN THE FILTRATION OF CANE 

 JUICES AND SIRUPS. 



CALUMET SUGAR-HOUSE, BAYOU TECHE, LA., 



Wednesday, February 29, 1888. 



DEAR SIR : Pursuant to the conditions attaching 9 tons of German 

 lignite furnished him by the U. S. Department of Agriculture for ex- 

 perimentation in cane- juice nitration at this factory, I am instructed 

 by Mr. Daniel Thompson, its proprietor, under whose exclusive patron- 

 age the experiments have otherwise been conducted, to make you the 

 folio wing report concerning the same : 



A miniature apparatus comprising mill, steam -defecators, open steam- 

 evaporators, subsiders, and a laboratory, frame filter-press from Wege- 

 lin and Hiibner, center- feed, executed in bronze, of one-half square foot 

 filtering area, arranged for complete displacement, offered reasonable 

 facilities at all times to small work. Four Kroog presses of thirty 

 frames, 220 square feet filtering surface each, so mounted with respect 

 to receiving vessels, juice, and lixiviating pumps, safety- valves, and like 

 appurtenances as to have operated upon scums throughout the season 

 without suggesting alteration, besides eliciting the eulogiums of the 

 inventor of the so-called Brown coal process, served during industrial 

 trials. All pipes were of copper or brass, pumps of bronze, and the 

 plates, perforated sheets, frames and other iron parts of the apparatus 

 in contact with juice all thoroughly painted, as insurance against dis- 

 coloration of products. A well arranged chemical laboratory, unusually 

 well equipped for investigations connected with sugar, was also pro- 

 vided. 



Mr. B. Kemmers, an English expert in mechanical filtration and sugar 

 refining, well known to readers of the Sugar Cane Magazine, assumed 

 technical control of the experiments, assisted by Mr. 11. A. Williams, 

 chemist from the Louisiana Sugar Experiment Station, Mr. J. P. Bald- 

 win, a local adept in defecation, and two long-time employe's of the 

 factory. 



A preliminary study was made of cake formation. For this pur- 

 pose Spanish whiting, variously colored, as with aniline dyes and 

 alizarine, kept mechanically suspended in water by vigorous agitation, 

 was pumped into the chambers, the cakes being finished off at high 

 pressures to insure extreme solidity, which, after removal, were cut 

 into sections, longitudinal and transverse. It was found that, with con- 

 stant or very gradually increased pressures maintained within the cham- 

 bers, and a liquid kept under unaltered conditions, the cakes formed by 

 extremely uniform accretions, beginning with a thin and even coating 

 of the entire filtering area, over which the various colors used deposited 



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