Corrosion Inhibitor for HCL | Oil & Gas
Posted by Ben Wiggins on 1st Feb 2024
28% HYDROCHLORIC ACID CORROSION INHIBITOR
THE PROPOSITION
A large Middle Eastern oil drilling and producer approached us to test and supply an acid corrosion inhibitor for use with 28% HCL (Hydrochloric Acid)product for drilling & workover operations that usually run at high temperatures ie. greater than 180 degf
As a result of these operations they normally see high levels of corrosion and large build ups of corrosion debris. These two factors generally cause multiple un-planned shutdowns andworkovers. The customer requested Chemiphase to find a solution to reduce the levels of corrosion and blockages so allowing them to organise better production runs and reduce their capital equipment costs.
TESTING PROCEDURE
The approval of our product involved an onsite testing procedure, using a standard 2-4-2 style corrosion inhibitor test , where by test coupons were placed in glass vials, that contained the 28% hydrochloric acid and varying levels of the corrosion inhibitor recommended. These vials were then placed in a heated bath, and warmed to 100 deg F.
The coupons were weighed before and after testing, as descibed by the normal testing best practices set forth by “NACE Recommended Practice RP-0775” and “ASTM G-1 & G-4.”
The acceptable Inhibitor efficiency was deemed to be a minimum of 88-92%, due to the severity of the problem. As can be clearly demonstrated, the results show an average of 97.57% Inhibitor Efficiency.
Gravimetric Measurements were carried out and inhibitor efficiency calculated using the equation
IE = W(Corr) – W(Corr)1 X 100
W(Corr)
Where W(Corr) = Corrosion rate blank and W(Corr)1 = Corrosion rate with inhibitor
TEST RESULTS
100 deg F |
||||||||
Test No | 1 | 2 | 3 | 4 | ||||
W(Corr)Lb/100ft² | IE (%) | W(Corr)Lb/100ft² | IE (%) | W(Corr)Lb/100ft² | IE (%) | W(Corr)Lb/100ft² | IE (%) | |
Blank | 13.94 | / | 10.72 | / | 13.94 | / | 13.94 | / |
1% | 0.37 | 97.29 | 0.39 | 96.50 | 0.36 | 97.52 | 0.42 | 97.04 |
2% | 0.31 | 97.83 | 0.30 | 97.21 | 0.247 | 98.10 | 0.30 | 97.99 |
3% | 0.22 | 98.46 | 0.28 | 97.33 | 0.30 | 97.83 | 0.27 | 97.78 |
CONCLUSION
The Chemiphase inhibitor shows a higher than acceptable level of performance. This results in the corrosion levels significantly decreasing, which in turn results in a reduction in down time and maintenance costs.