Sandstone addizing

Sometimes this is left undone, especially when there is a race against the clock to complete a treatment. Advanced planning is essential, to avoid such oversights. Flowing an addized well as soon as possible, with minimal delay, is an underrated concern in sandstone addizing. 

Fines are generated during sandstone addizing and are carried more efficiently by more viscous or more dense spent acid mixtures. To avoid potentially damaging effects, the flow rate should be set low at first. Then, after spent add is produced back, the flow rate should be gradually stepped up to planned production conditions. 

As previously discussed, the most common purpose of matrix addizing is to restore near-wellbore permeability in or through a damaged formation zone. Because it is bypassed, rather than directly removed, formation damage in a candidate for carbonate acidizing need not be acid removable by contrast, it does need to be add removable in a candidate for sandstone acidizing. 

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