The formation of oil-field emulsions

NOTES THE

FROM

THE

FORMATION

U. S. BUREAU OF

OIL-FIELD

OF MINES.” EMULSIONS.

By D. B. Dow. TILE appearance of water in an oil field is the forerunner of various difficulties, and probably represents the greatest technical problem that the producer must face. Water conditions bear directly on the quantity of oil recovered, and the length of the life of a field. Presence of water increases the cost of operation, for example, lifting costs. On account of the corrosive action of oilfield waters on pumps and other equipment, frequent replacement of equipment is necessary. Furthermore, water may affect the marketability of the oil produced, as detrimental emulsions of water in oil (“ B. S.,” “ cut oil,” etc.) are often formed. The writer has recently completed a study of oil-field emulsions. The factors responsible for the formation of emulsions are described in Serial 2683 and methods now utilized for dehydrating oil-field emulsions are discussed in Serial 2688.

FRICTION

FACTORS

FOR

By G. E. McElroy

METAL-MINE

AIRWAYS.

and A. S. Richardson.

1%‘~ made a large number of careful determinations of the resistance to the passage of air in selected sections of airways in the metal mines of Butte, Mont. From the data obtained we compiled a table of friction factors, or coefficients of friction, that is, values of K in the generally accepted formula for air flow of pK!! or H= __KSV2 where, in units customary to

,4 x

5.2*

mining practice : P-total pressure loss in pounds per square foot, H = total pressure loss in inches of water (at 60” F.), S= total rubbing surface in square feet-4 x P, I_ = length in feet, P- perimeter in feet, V = velocity in feet per minute, .4 =area of cross-section in square feet, and k’= friction factor for air weighing 0.075 pound per cubic foot. * Communicated

by the Acting Director. ‘33