Abstract
This paper describes lab studies and field results on how a new Zeta Potential Altering System (ZPAS), utilized in fracturing treating fluids, improves gas rate production. Lab and field results show ZPAS minimizes proppant flow back and coal fines migration, enhances fluid load recovery, and inhibits calcium carbonate scale formation. The mechanism of this system based on an inner salt that modifies the Zeta Potential on particles such as frac sand and formation substrate, changing the charge towards neutral values and therefore enhancing particles agglomeration.
This paper also shows how the Zeta Potential Altering System has been applied in numerous coalbed methane wells which were treated by refracturing. The ZPAS has been run in borate cross-linked fluids and linear gel systems. Field results have been positive on wells treated, with less time to clean out frac sand, less flow back sand and coal fines, higher conductivity after load fluid recovery, and higher gas productivity after load fluid recovery and de-watering of CBM Zones. Production has increased up to 15 fold on individual wells with 3 to 20 months production history.