22 



ciently fine filtering surface of focnlent matters and charcoal has been formed on the 

 surface of the cloth. 



.Juice treated with brown coal, on the other hand, runs quite bright or nearly so 

 from the first running of the press, decolorizes considerably, and the cakes formed in 

 the press part easier with their sugar when it is desired to wash them out than cakes 

 formed of vegetable char. 



For your future guidance allow me to suggest what I consider the best mode of 

 treating juice with brown coal to effect rapid and good nitration and at the same 

 timo use the minimum amount of brown coal in the operations. I make this sugges- 

 tion on the supposition you are carrying out your experiments on an estate contain- 

 ing all the most modern appliances for successfully treating after it has been filtered, 

 namely, double or triple effects vacuum-pans and centrifugals. 



After the juice has been defecated in the usual manner allow it to subside for a 

 few minutes, then brush off the skimmings into a tank and run the juice into another 

 (preferably a circular one fitted with revolving stirrers), where the brown coal has to 

 be added. As soon as the bottoms are reached they also have to be run into the 

 skimmings tanks The brown coal is now added to the tank containing the juice, 

 and after being thoroughly mixed it is forced through the filter press, finishing off 

 with a pressure of about 75 pounds per square inch. In some cases 50 to GO pounds 

 pressure will be found quite. sufficient, and a speed in the filtration ought to be ob- 

 tained of 9 gallons per square foot of filtering area per hour, or for a press containing 

 400 square feet of filtering area 3,600 gallons per hour of filtered liquor. After the 

 thin juice has been brought to about 20 Baum6 in the triple effect, certain albu- 

 minous compounds that were soluble in thin juice now 1 precipitate out at the higher 

 density, and it is necessary to again add some ascertained proportion of brown coal 

 to the liquor and pass through a press before being taken into the vacuum-pan. 



By the action of the brown coal the liquor is considerably decolorized at this point, 

 and as all gummy matters have been previously taken out of the juice the liquor will 

 filter through rapidly by simple gravitation from a tank situated 6 to 10 feet above 

 flu- press. The cakes taken from this press are used over again for the filtration of 

 the defecated juice. The skimmings and bottoms are mixed either with fresh brown 

 coal or with that taken from the gravitation-press and filtered in a press by 

 themselves. By dividing the work in the manner I. have suggested, more work can 

 be got through in a given time, with better results and using a smaller proportion of 

 brown coal, than if it had been added to the juice, skimmings, and bottoms together 

 in the defecating tank. 



Tests were made on a laboratory scale with lignite from Avery's Isl- 

 and. The results were very satisfactory. It is proposed to repent 

 these experiments on a large scale. 



TEST OF THE KLEEMANN PROCESS AT MAGNOLIA. 



Early in December, at the request of Mr. D. D. Colcock, of the Sugar 

 Exchange, New Orleans, the Commissioner of Agriculture directed me 

 to test this process on a practical working scale. 



A sufficient quantity of lignite could not be procured, so, in accord- 

 ance with the suggestion of Mr. Ernst Schulze, representing the own- 

 ers of the process, finely ground charcoal was substituted. Experiment 



1 This was not the case in the experiment at Magnolia. The sirup remained per- 

 fectly clear without the slightest trace of precipitate. There was no necessity for a 

 subsequent settling or filtration of the simp. G. L. S. 



