Kabelwerk Eupen AG Eupen, Belgium developed a computer controlled device called a Eucastream in which the slotting is precisely calculated for a specific yield in gallons per minute and formation permeability to distribute the energy precisely uniform for the column height of the screen. Both Aquastream and Eucastream SFCD devices operate from the same physical principle utilizing a slightly different means to accomplish the intended purpose.

It has been found that it is not necessary to shift turbulent flow to transitional or laminar flow to stop sand pumping. Sometimes it is only necessary to shift the flow to a different zone in the formation of slightly better permeability thus reducing the flow velocity and sand production from the previous zone. Benefits have been observed for screen intervals as short as 10 feet. Normally the benefits are greater with longer screen intervals.

Sand control may be achieved by shifting the velocity to a more stable portion of the formation without a significant increase in well specific capacity. In many cases however there is a significant increase in well specific capacity due to the shift of the energy velocity allowing transitional or laminar flow to occur in the formation. The maximum increase in specific capacity that can be achieved is approximately 2.35 times the natural developed specific capacity for an efficient well. Sometimes a partial increase in specific capacity is achieved that is allowable by the formation permeability and length of screen installed during the original construction of a well.

The primary control of water yield from a well is regulated by the formation permeability available around the well bore and the thickness of formation penetrated by the well screen or formation. If the well formation permeability has deteriorated due to biofouling, mechanical or chemical plugging, then the suction flow control device cannot operate properly.

CASE HISTORIES

Madison, Indiana utility system had two 5 year old sand and gravel wells in the Ohio River Valley that pumped excessive sand and had to be shut down. An Aquastream SFCD was installed inside of a 16 inch diameter screen, 30 feet in length in a well 138 ft. depth with this unit attached to the suction nozzle of a vertical turbine pump. It was a complete success from the start and four years later continues to produce more than 1,000 gpm of sand free water at a better specific capacity than originally developed from the well.

Ft. Bend County, Texas W C & I D No. 2 had well. No. 3 with 220 feet of 10 inch diameter screen in intervals spread through the bottom 800 feet of a 1,600 ft. deep well. The well pumped more than 2,500 ppm of sand at 800 gpm and was used for stand by service only. Aquastream units 6 inches ID by 8.25 inches OD were set-inside the screen intervals properly spaced and sealed to the upper 16 inch casing by a packer seal serving as a liner. After installation of the SFCD the well produced 1,350 gpm with a measured sand content of 0.1 ppm with a 30% improvement in well specific capacity.

In Wisconsin, a 400 feet deep sandstone open hole well produced excessive sand with pumped water. An eight element 6 inch ID by 8.25 inch OD Aquastream SFCD was installed attached to a shroud surrounding a submersible pump. The result was complete control of sand (no sand production) with an improvement in well yield.