Improvements in treating, purifying, and sterilizing water or contaminated liquids, and an apparatus therefor / [William Lawrence].

  • Lawrence, William
Date:
1895
Catalogue details

Licence: Public Domain Mark

Credit: Improvements in treating, purifying, and sterilizing water or contaminated liquids, and an apparatus therefor / [William Lawrence]. Source: Wellcome Collection.

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    Lawrence s Improvements in Treating, Purifying, and Sterilizing Water, (f'c. A convenient form of heat interchanger is one resembling that already shown for smaller purposes and for private houses. A convenient form of boiling vessel for baths and washhouses and for general purposes for softening and sterilizing water under columnar pressure is the cylindrical form, the depth being 10 or 12 feet or h such depth as will give in the boiling chamber a columnar pressure that will raise the boiling temperature 10 or 15 degrees above the atmospheric boiling point. The vessel would be separated into compartments by diaphragms or shelves or trays perforated or with spaces between, and would have in addition a sludge chamber and a depositing chamber. Pressure steam would be the heating medium 10 for adding the heat required over and above that which would be imparted bv the heat interchanger. The steam would enter the water above the bottom diaphragm and making its way upwards would be condensed and absorbed in the descending water. The water would then pass through the perforations in the bottom diaphragm into the depositing chamber and being diverted downwards by a baffle 15 plate would rise on the other side and leave the apparatus at the top part of this chamber and return to the heat interchanger. A heating vessel for softening and sterilizing for house purposes under columnar pressure is a vessel similar to that already described for sterilizing and softening but of increased size according to requirement. 20 If placed 6 feet or 12 feet or any convenient distance below the delivery tank, the crude water could descend to the boiling vessel from the supply tank and could ascend to the delivery tank; by suitable pipes passing to and from the heat inter- changer on its way. Other shaped vessels may be used in treating water under columnar pressure and 25 the waste gases from the furnace may be employed as the heating medium. For example, a series of rectangular pressure tanks stacked one above another and connected by pipes and having spaces for dues between them, may be set in brickwork so as to economise the heat from the furnaces and also soften the water. 30 An important feature where columnar pressure is a factor is the prevention of encrustation in kitchen boilers. It is generally supposed that the circulation of water between the kitchen boiler and the supply tank is due alone to a difference of temperature between the columns and that heat is the sole cause of the circulation. This however is not the case. The 35 ascending column rises because it is lighter than the descending column but the cause of the difference is not alone heat but whatever makes one column lighter than another. Liberated air and water mixed are lighter than water; water and steam are lighter than water. Keeping these facts in view, I employ a circulating cylinder specially made with 40 diaphragms perforated and having a settling chamber with baffle plate as already described. I then circulate the crude water to and from the supply tank to the top part of this chamber and the softened and clarified water between the boiler and the bottom part of this cylinder. In action, the water owing to ebullition in the kitchen boiler starts in circulation 45 and carries with it the steam evolved ; on reaching the circulating vessel the steam and water become separated the steam passing upward and the water passing downward carrying any deposit down with it and then rising to the outflow or return pipe to the boiler. Thus there is no connection established between the water flowing to and from 50 the boiler to the bottom of the cylinder and to and from the top tank to the top part of the cylinder. But the steam evaporated passing upwards becomes condensed, and the make up water passing downwards becomes softened and deposited. There being then practically a separation of the crude from the softened water by means of the perforated diaphragms, the question of encrustation due to -55 carbonate hardness is satisfactorily disposed of. It might be objected that a jarring noise such as when steam is blown in to water would result from the system above described, but this would be guarded against by