Preliminary Evaluation of Silica Sand in Sudan with Respect to Fracture Sand

Since its introduction in 1948, hydraulic-fracturing has been one of the primary engineering tools for improving well productivity in tight or low permeability reservoirs; it is used to increase or restore the rate at which fluids, such as petroleum, water, or natural gas can be produced from reservoirs. Due to its effective performance, the technique has progressively expanded so that by the end of 1955 more than 100,000 individual jobs had been performed (Economides 1989); the process has been employed to enhance the production of oil and gas from underground reservoirs for more than sixty years. Recently, the exploration of the unconventional resources was widely increased; then, the need for massive hydraulic fracture job was also increased. The technique in generally use to by-pass formation Damage and increase drainage Area; also, it can be used to connect the wellbore with disconnected zone, and was widely used to control sand production from friable formations.

The process requires an array of specialized equipment and materials; it is involves injection of frac-fluid at a high pressure into a selected section of wellbore; this fluid pressure creates a fracture extending into the rock medium which contains oil or gas. When the fluid pumped into a well, necessarily the pressure rises, and at some point something breaks (either the rock or the equipments); as the rock is generally weaker than steel, the formation will breaks, resulting in wellbore fracturing along its axis. To maintain fracture opening during the production life of the well, solid substance with specific characteristics (known as proppant) injected to the fracture to suspend the fracture.