Specification of William Johnson : method of heating fluids.

  • Johnson, William.
Date:
1854
Catalogue details

Licence: Public Domain Mark

Credit: Specification of William Johnson : method of heating fluids. Source: Wellcome Collection.

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    Johnsons Improved Process for Heating Fluids. fire to supply steam, represented by A, be made of sufficient strength to bear a high pressure of steam, on which let there be a safety valve, to be loaded «» according to the heat of steam requir’d, as shewn at C ; to w7hich boiler let a main pipe be fix’d, as represented by D, having smaller pipes as E, E, to 5 convey the steam to the different receptacles, on which pipes and on the main must be fix’d cocks or valves, as F, F, F, to be regulated by a weight, to govern the direction and quantity and temperature of the steam to be discharg’d ; let another boiler, as represented by B, be form’d (open or close at the top, according to the purpose for which-it maybe intended,) of dimensions requir’d, 10 suppose double the dimensions or superficial content of that on the fire, for the use of the steam engine or manufacturing purposes, and having a close recep¬ tacle of a few inches depth, form’d as represented at G (or any other form) at the bottom of the vessel, for receiving the steam from A by the pipe E, and that, if were requir’d, that the water or other fluid in the larger vessel B shou’d be 15 made to boil, and evaporated at the heat of 212 degrees or common boiling; let the temperature of the steam in A be rais’d to about 248° (as near as is at present ascertain’d), which when discharg’d at that temperature into the receptacle G will boil and evaporate the fluid contain’d above it in the vessel B as rapidly as can be affected at the same temperature by the direct action of 20 fire; consequently, if the temperature of the steam discharg’d from A was always preserv’d at about 278 or 280 degrees, it appears by the tables of the ascertain’d power of heated steam, that when it is rais’d to that temperature that it will be of double the power of 248°, or be sufficient to evaporate double the surface with equal rapidity; and therefore, if it were requir’d by this process 25 to evaporate water as rapidly (as by the direct action of fire) from the boilers at present in use for the condensing steam engine at a temperature of 225 degrees by the same proportion’d vessels, that this will be effected by the same process, and raising the temperature in A to the proportionate heat required. It will be understood, that whilst communicating by steam so rapid a heat to a larger 30 vessel, that about the same quantity of steam will evaporate from the small boiler A as will in the same time be evaporated from B. To provide for this rapid evaporation from A, it will be necessary either to have that vessel much deeper than B, which for some purposes will be prefer’d, or to supply it again by a forcing pump with the water from the receptacle G, produced by the con- 85 dens’d steam from A. This must be convey’d by a separate main and communi¬ cating pipes distinct from the steam main; the returning the water at an inferior heat to the boiler is in practice with the condensing steam engine where the supply water is return’d at about 100 degs temperature, whilst the water in