Airlift method is used to remove water and submerged solid particles from the water well. The advantages of this method make it a perfect replacement for common drilling and dredging methods employed for operating wells. By such a method, compressed air is infused to the airlift pump located deep down the well. The air is then released inside the well making a mixture of water and air with a density less than the surrounding water, causing a lift of the mixture. The result is a three-phase flow through the embedded pipe to the outside of the well carrying the removed debris, sand and gravel.

We are able to clear the wells of deposits with liquid Nitrogen and Airlift pump up to the depth of 350 m. In comparison to drilling, this method is:

• • capable of removing coarse size solids of sand, gravel and rubbles
  • more reliable
  • faster in removing debris
  • capable of removing debris even in wells with deformed or ruptured casings
  • not damaging casings of old wells.

The equipment inspects the well casing interior by providing the simultaneous video displays of four cameras. The video inspection equipment is used to determine the depth of the well and to display casing connections and screens condition. In addition, casing corrosion, screens deterioration and incrustations, deposits or biofilms on well casing are visible in video inspection. The results of the inspection help us to identify well problems and offer best solutions. The water well video inspection equipment provides:

• Real-time simultaneous video inspection with four cameras
• Video inspection of up to 300 m depth (can be improved to 500 m) and 35 bar pressure
• Video inspection in casings with at least 8” inner diameter
• Real-time data display, such as inspecting depth, on screen
• Adjustable 3D lighting intensity
• Three lateral cameras for complete 360° circumferential inspection coverage
• High definition (HD) recording
• Smooth cameras motion with automatic cable retractor
• Fast and easy operation

Over the operation time, water wells gradually lose their discharge rate due to many reasons including: mineral incrustation, migration of fine-grained soil into the well and microorganisms’ activities. The severity of this process depends on the well and aquifer conditions, but the followings can be a sign of such problems:

• Reduction in discharge rate over time
• Increase in pump power consumption
• Observation of sand in pumped water and water quality degradation
• Lower dynamic level

Accurate identification of the problem and well condition is obtained by video inspection, then chemical or physical methods, or combinations of both, according to experts, are used to rehabilitate the well, resulting in:

• Increase in discharge rate
• Decrease in power costs
• Elimination of sand in pumped water and water quality enhancement
• More durability of electromotor and pump
• Well development and incrustations removal radially, even beyond gravel pack
• Elimination of stress on casing and reducing the risk of casing destruction

 

Incrustations removal by chemical methods

In wells with hard incrustations where incrustations removal is not applicable by common physical methods, chemicals are used. These materials dissolve sediments on casing, gravel and aquifer and loosens incrustations. Then, the dissolved and loosened sediments are removed from the well by brushing, surging or pumping.

Incrustations removal by compressed air impact (Airshock)

The most modern water rehabilitation technology used all around the world is Airshock method. This system causes the burst of compressed air inside the well in a fraction of a second. The compressed air at the pressure of 20 to 200 bar outbursts in less than 5 milliseconds, creating a powerful wave that crushes the hard incrustations and disjoints them from the casing. This operation cleanses the screens and gravel pack resulting in discharge rate increase.