In some cases a well slowly loses production yet the casing pressure indicates there is sufficient amount of pressure for the well to produce. Many factors can cause this such as loading of the well, scale problems, salt problems, sanding off (bridging) as well as slime or sludge which will all built up on the perforations or in the tubing or casing causing constrictions which do not allow the well to flow to its full potential.

In a Natural Gas Well there are solutions but most require an unneeded expense as in many cases the problems can be solved by the introduction of Acid Cap Sticks directly to the source of the problem. Unlike conventional acid jobs the reaction with the acid only occurs in the problem area thereby not affecting any other part of the system and in most cases the well is returned to regular flow in a short period of time.

The process for doing this will depend on how severe the problem is but in most cases 2-3 of 100% active Acid Cap Sticks (Allow a few minutes for the sticks to reach the problem) followed by 40 Litres (10 gallons) of water (If there is no water present or if the well is plugged and there may not be water above the plug itself) will start to react to the problem in a very short order. As the reaction is only at the problem area the rest of the system is not compromised.

This is true in natural gas wells and dependent on the problem you may require up to 10-20 sticks for this to be solved. At the same time in Oil Wells we must have a high enough water cut to activate the sticks and because of the oil the reaction time will be slower and it may also be dependent on the downhole temperature as the higher the temperature the time frame for the stick to react will be diminished.

Another application where these sticks have worked with great success is on wells with bumper springs, pumps or other equipment downhole when a maintenance work-over is scheduled by dropping the 1-2 Acid Cap Sticks the day before this can alleviate any issues that may prevent the wireline unit or other equipment from being able to carry out their work with no issues therefore saving time and money.

Be it scale, salt, sand or other similar problems, I have seen a totally plugged off well where a Wireline unit could not get a tool down return to production overnight and others where there was a buildup on the perforations or in the tubing increase its production by alleviating the problem downhole.

Because the reaction of scale, salt and other similar problems plus the water neutralize the acid solution this has never caused any issues for both well integrity and personal. If these wells are a constant problem then I suggest putting them on a maintenance schedule of 2-3 sticks a week using the proper prescribe stick (Salt Stick, Scale Stick, Sand Stick or a Standard Acid Stick (30% Active) for that issue.