Tank (hydrology)

“ The James River is mined with fifteen tanks below the iron battery at Chapin’s (Chaffin’s) Bluff. They are to be exploded by means of electricity. Four of the tanks contain 160 pounds of powder; the eleven others hold 70 pounds each. All are made of boiler plate. They are arranged in rows as per diagram, those of each row being 30 feet apart. Each tank is contained in a water-tight wooden152 cask, capable of floating it but anchored and held below the surface from three to eight feet, according to the state of the tide. ”

“ But if tanks are constructed of substantial and enduring materials, they possess little if any advantage, on the score of expense, over hot water pipes, while they occupy much more room and are unsightly objects in a well ordered green-house.
Wooden tanks are frequently used where the heat is required to rise perpendicularly from them. If constructed of good pine plank, well put together with white lead, and thoroughly painted inside and out, they will last for several years. Scarcely any heat will be radiated from the sides and bottom of a wooden tank. ”

“ The system of leaching, as it is termed in the States, is conducted as follows:—Iron tanks are used, with suitable piping, that allows pumping from one tank to another, and also to pump from any one of them up to the causticising tanks in the alkali-room. There is also a water-line by which water may be pumped into any of the tanks, and there is a spout used in washing away the black ash sludge. The leaching-tanks have false bottoms of 2in. by 2in. stuff, placed crosswise, over which is a layer of gravel, on which lies a layer of straw, by which the liquor is filtered. ”

“ A tank is an artificial receptacle for liquids, thus: a tank engine is one which carries the water and fuel it requires, thereby dispensing with a tender; tank-iron or steel is common plate used in building tanks. Steel is cheaper than sheet-iron. A cistern is primarily a natural reservoir—a hollow place containing water; more commonly an underground reservoir or tank. Closed pressure tanks are usually cylindrical shells similar to a horizontal steam boiler, having bumped or rounded heads to save bracing. Closed pressure tanks are used extensively in connection with hydraulic elevators ”

“ It puts the producer in direct communication with the carrier and a market at all seasons, regardless of high or low water, rain or storm, mud or dust. The tanks at his wells are connected with the pipe-line by one or more of the two-inch feeders that spider-web the producing-country. Small pumps force the crude, when the location of the well prevents running it by gravity, from these tanks into a receiving-tank of the line, whence it can be piped into the trunk-lines or a storage-tank as desired. ”

“ When a large pit is excavated, fissures, through which water is seen to be freely circulating, are nearly always exposed. Experiments show that—provided a sufficiently large collecting-tank is made, measuring, for instance, 5 by 4 metres, and sunk from 1 to 2 metres below the standing water-level—a supply sufficient to yield a continuous discharge of 8 gallons a minute (equivalent to 11,500 gallons per day of twenty-four hours) can frequently be obtained. ”

“ It is common, therefore, to put in, just back of or above the closet, a small copper-lined wooden tank which holds about three gallons and which can be discharged rapidly through a one-and-a-quarter-inch pipe. This tank with fittings costs about $10, and in a great many cases is probably unnecessary. It has the advantage, however, of allowing a small flow to enter the tank whenever emptied, to be automatically shut off by a float valve when filled. ”

“ Where a steel tank is sunk, or a masonry tank is constructed, regard must be paid, both in the design of the tank and in the manner of construction, to the level of the underground water in the neighbourhood, as in certain cases special precautions will be needed to avoid trouble from the pressure of the water on the outside of the tank until it is balanced by the pressure of the water with which the tank is filled. ”

“ The principle objections to tank heating, as usually employed, are an excess of bottom heat and a deficiency of atmospheric heat, with a superabundance of moisture when the vapor from the tank is not properly excluded from the house. Tanks should be covered with some good radiating material, as slate or metal. If slate is employed, the joints should be carefully and effectually cemented. ”

“ The pressure being relieved from the tank, take out the head, use about a water-pail full of fine salt to settle the tank. This salt is scattered over the contents in the tank and has the effect of settling sediment and tissue which may be held in suspension. The tank should stand about two hours to thoroughly settle before drawing the oil. Draw the oil from the side valves of the tank into coolers. It is often necessary, in doing this, to raise the contents of the tank, as there may be considerable tallow or lard below the lowest draw-off valve. ”

“ In this respect many farm and country houses are found to be but very imperfectly supplied. Often the tank is placed only slightly higher than the second story of the house. As a result, the water flows sluggishly at the bathroom faucets, and, in case of fire, no effective fire stream can be thrown. Where a reservoir is suitably located above the house, the pressure is sometimes lost by laying pipes too small in diameter to furnish an ample stream. Elevated tanks should always be placed so high as to afford a good working pressure in the entire system of pipes. ”

“ A settling tank is simply a galvanized iron tank with a large faucet at the bottom. The bottom can be made to taper to the center and the faucet placed in the center, so all the water can be drained off, or the bottom can be made flat with the faucet close to the bottom, and the tank can be set slanting, so the water or Lard will all drain out. ”

“ I may mention that a great effect has been produced in the case of a tank on one of my coffee estates by thus digging pits to catch water that would otherwise run directly down into the tank, to be largely lost by the overflow during heavy rains, and a similar effect has been produced on the property of a neighbour. In fact, the effect produced by such pits on the supply of water in tanks is far greater than one could have imagined to be possible, and I may therefore, in passing, call particular attention to the advisability of such pits being made near tanks used for agricultural purposes. ”

“ In places which are still less fortunate and, especially in dry times, are at a greater distance from the precious element, there still remains a plan by which sufficient could be secured, and that is the portable water-tank. Our agricultural machinists now turn out handsome and capacious iron tanks which are coming into general use. Now, no one farmer can be expected to send water-tank and team three or four times every evening to fetch [Pg 180] up water for the use of cottagers, not one-twentieth of whom work for him. ”

“ And speaking of the standard fifty-five-thousand-barrel steel oil tanks, the reader may be interested to know that they are thirty feet high and one hundred and fifteen feet in diameter, are usually surrounded by an earth dam to save the oil in case of accident, and have usually a bottom valve through which the oil may be drawn off if a bolt of lightning fires the tank. ”

“ The Travis Hydrolytic Tank when first designed differed from the later design of the Imhoff tank in the slot between the sedimentation chamber and the digestion chamber which was not trapped against the escape of gas from the latter to the former, and in operation a small quantity of fresh sewage was allowed to flow through the digestion chamber. The tank is called a hydrolytic tank because some solids are liquefied in it. The tank is mainly of historic interest as designs similar to it are rarely made to-day. Better results are obtained from the use of the Imhoff tank. ”

“ A cesspool or sewage tank, if required, should be built thoroughly tight, tighter even, if this were possible, than a cistern. It should be of moderate dimensions, preferably circular in shape, built with hard-burnt brick, laid in hydraulic cement, and the tank must be well rendered inside and outside with pure Portland cement. The tank should be arched over and covered with an iron cover. It must be emptied, cleaned and disinfected at frequent intervals, and [44] it should be at all times well ventilated, by a pipe, carried up to a good height above ground. ”

“ It has been found that a tank, in order to do successful work in separating solids and in eliminating as much as possible of the sediment, needs to be of a capacity to equal about one day's flow of the sewage, and this is a good basis for computation. ”

“ The gas vents should be made large enough so that access can be gained to the sludge chamber through them when the tank is empty.
Precautions should be taken against the wrecking of the tank by high ground water when the tank is emptied. With an empty tank and high ground water there is a tendency for the tank to float. The flotation of the tank may be prevented by building the tank of massive concrete with a heavy concrete roof, by underdraining the foundation, or by the installation of valves which will open inwards when the ground water is higher than the sewage in the tank. ”

“ Another method of ensuring uniformity of flow over the whole area of a tank, is to arrange it in the form of a wedge, with the inlet at the 39 narrow end and the outlet in the form of a weir at the wide end. This form of tank is shown, Fig. 134, page 183, for settling out the humus in filter effluents. The same tank, with a greater depth, would be equally suitable as an ordinary sedimentation tank for sewage, and several could be arranged in such a way that three or four would form a half-circle, i.e. the angle between the two side walls of each tank would be 60 degrees or 45 degrees. ”

“ Copper tanks are used as receptacles for the fat and the water, but the steam to communicate the heat is generated in a large iron boiler thirty feet in length and forty inches in diameter, with which the copper tank is connected by means of steam pipes furnished with stop-cocks as regulators in the use of the steam. There is also a shaft in the tank having radial arms, which shaft is kept in rotation to cause and preserve an intimate mechanical mixture of the fat and the water during the whole operation. ”

“ Thus there were nearly a hundred animals in this Tank; a number which I found far too great; for though they did not crowd the vessel at all apparently, nor seem disproportioned to the space they occupied, it became evident that the exhaustion of the oxygen of the water went on more rapidly than it could be renewed, either by the evolution from the living plants, or by the combination with this of artificial aeration, by allowing two or three gallons a day to drip from a vessel suspended over the Tank at the height of about four feet. ”

“ After settling for a time the clear juice is drawn off and the scum, mud and cloudy liquor left in the tank. As a vast amount of liquor must be handled every hour, it is not practicable to have tank capacity great enough to admit of the liquor standing a sufficient length of time for every particle of foreign matter to settle, so as an adjunct to the settling tank, filters are used. These are cylindrical iron tanks, packed tightly with ordinary wood fiber, known as excelsior. ”

“ Time of emptying, 5 minutes. Time of filling, 10 minutes. Shape of tank is a right pyramid or a truncated right pyramid with all four sides making an angle of 45 degrees with the vertical. All horizontal cross-sections are squares.
For example, if the given head is 6 feet, and the rate of inflow is 1.4 sec. feet, it is evident from Fig. 173 that a 6,300–gallon dosing tank and two 8–inch siphons will give the required cycle.
The method used for the design of the setting of Taylor nozzles by the Pacific Flush Tank Co., is less rational but more simple and probably as satisfactory. ”

“ And in the open tank evaporation is constantly deranging this, and must be met by a supply from without. As the pure water alone evaporates, and the salts and earthy or mineral constituents are left behind, two things result: the water remaining becomes constantly more dense; and this can be remedied only by pure fresh water poured in to restore the equilibrium. Hence the marine aquarium must be replenished with fresh water, until the proper specific gravity, as indicated by the hydrometer, is restored. ”

“ The latter can be painted at intervals, so that it will not rust, and is safer than wood alone to prevent leakage.
Care must be taken to give sufficient strength to the wooden tank; it should never be made of less than two-inch stuff, and should not depend upon nails or screws alone for holding the sides together. Figure 56 shows a suitable way to put together such a tank. Certain firms that make windmills and agricultural implements generally can furnish wrought-iron tanks, warranted to be water-tight, of suitable size to go in an attic. ”

“ Rods put on other structures save them; but rods have been put on oil tanks, masts with rods have surrounded the tanks, but the tanks were exploded by lightning all the same.
We will repeat a possible explanation which we have heretofore given. From every oil tank, according to our theory, there is a constant escape of light hydrocarbon vapor, which forms a permanent cloud or column, rising to a great height above the tanks, far above any rod that could be erected. This vapor rod is a conductor, which the lightning naturally follows, sets on fire the vapor, and explodes the tank. ”