With an available supply of air under pressure the pump proper consists of simply a water discharge and air pipe, the latter arranged and properly controlled to inject air into the former at the point of proper submersion. It is readily seen that the apparatus is so simple that as a pump it cannot get out of order; in cases, where mud, sand or gritty material is encountered, it will handle such matter with the water and without injury to the system, as nothing comes in contact with the moving parts.
Figs. 384, 385.
Absence of all obstructing mechanism in the wells allows each to be operated to its full capacity. Production, therefore, does not depend upon the pump, but rather upon the capacity of the well to yield water; the natural yield of wells is often increased by this process of using compressed air admitted close to the bottom of the discharge pipe, the water is set in motion at a considerable depth, and by this action the well is “cleaned.”
Purification is effected by aeration during the process of pumping, the absorption of air by the water preventing the formation of unsanitary growths.
Three styles of well heads are shown in Figs. [383], [384] and [385].
The deflector head, Fig. [383], is attached to the well casing or discharge pipe by standards. This form of head piece is generally used where the water is to be raised to the surface, or just below the surface into a tank, where the air is allowed to separate itself, and the water flows to some central collecting reservoir, where it is used or forced by means of an ordinary pump to a higher elevation. The head piece offers no obstruction to the discharged water.
The offset discharge, Fig. [384], is adapted to situations where the water is to be pumped by air direct from the well to some elevation above the well.
The elbow discharge, Fig. [385], shows the common form of well head known as the elbow head, adapted to be used either as a cap for the well casing itself, or used in connection with a suitable discharge pipe.
The foot piece, or nozzle, which regulates the admission of air to the discharge pipe at the point where the air comes in contact with the water, thereby makes it possible to carry air at full pressure to the end of the air pipe, and utilizes the energy due to the velocity of the discharged air.