MODERN METHODS OF STREET CLEANING 



layer of red-hot refuse is always left upon the grate 

 when the ashes are removed and upon this the fol- 

 useof lowing load of fresh refuse is deposited. 

 Ashes and Under these circumstances the contents of 

 the ash wagon, when the work is well done 

 by the laborers, is about 361 pounds. Flues are ar- 

 ranged so that the heated gases may be directed up 

 the chimney or under steam boilers for the generation 

 of power. 



The burned waste matter is first transported to a 

 railroad siding and then to a separate part of the 

 works where it is cooled with water, ground up and 

 sifted. The ground clinker is sifted in a drum-shaped 

 screen, which is provided with holes of different sizes. 

 The material which is thus separated is caught in fun- 

 nels and conveyed to wagons placed beneath. About 

 16 per cent is very fine, 50 per cent of medium size, 

 and 34 per cent of coarse consistency. The metallic 

 substances are separated from the clinker and sold. 

 The dust from the flues is sold for the making of 

 artificial sand, and for other purposes. The ground 

 clinker is used for building purposes in place of broken 

 stone and gravel. At times the work of building is 

 so active that the production of ground clinker scarcely 

 meets half of the demand. 



Power is generated from the heat of the burning refuse 



by means of four boilers. The temperature of the gases 



which reach these boilers ranges from 450 to 



Generation of 



Power from 760 C. and averages about 600. The steam 



the Refuse . , ,. , , . 



is used for running the machinery necessary to 

 operate the plant, for a small a mount of heating on the 

 premises, and for the production of electric power which 

 is transported and consumed in other parts of the city. 



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