Carbonated water injection revisited

Abstract

Carbon dioxide is a major greenhouse gas, but also an effective agent for enhanced oil recovery (EOR). Large scale CO 2 -EOR projects are being carried out in the USA and Canada. However, such projects are not common outside North America due to limited supply of CO 2 . Carbonated water injection (CWI) process is to inject water saturated with CO 2 . The CO 2 in carbonated water diffuses into oil and results in oil swelling and viscosity reduction. CWI requires much less CO 2 supply. Several successful CWI field pilots were conducted in 1960s. Oil fields with good EOR potential and limited CO 2 supply should seriously consider CWI method.

Carbonated Water Injection for Enhanced Oil Recovery and CO2 Geosequestration in Different CO2 Repositories: A Review of Physicochemical Processes and Recent Advances

“…The field implementation faces concerns regarding global oil prices and process costs such as expenses related to CO 2 capture and transportation, drilling, CW preparation, pressure pumps, well completion, and operation and maintenance. Gao 30 revealed that despite the successes achieved in the Dewey−Bartlesville field and the White and Baker pilot projects, they were halted due to the low global oil prices and the expensive CO 2 acquisition from liquefaction plants. Despite the relatively low CO 2 volumes required for CWI compared to conventional CO 2 injection the feasibility of both techniques relies on the availability of a suitable CO 2 source.…”

“…43 Amoco Production Company's pilot test in Slaughter Field (Texas) to assess the impact of CW on equipment also confirmed that stainless steel and aluminum bronze materials experienced no deterioration. 30,180 However, Blackford 180 reported severe corrosion rates on the threaded and ring-type joint flange connections of the CW flood wellhead equipment. The corrosion was attributed to leakage in the threaded and flange connections where the plastic coating had cracked during flange bolt tightening.…”

“…The current oil production of 140000 barrels of oil per day can be increased while sequestering CO 2 as an additional benefit via CWI, considering various validated findings from experimental, field projects, and pilot projects, which affirm the exceptional performance of CWI compared to conventional waterflooding. 30,33,65 Assuming a CO 2 solubility of 51.05 g CO 2 /kg brine (equivalent to Salehpour et al 33 solubility results) and a CO 2 storage efficiency of 22−68% 33,66,68 (obtained from Table 4), about 91000−281000 tons of CO 2 could be safely and efficiently stored in the offshore reservoirs per year if secondary or tertiary CWI is considered. This represents a substantial reduction in CO 2 emissions compared to traditional waterflooding methods, highlighting the environmental benefits of CWI in offshore EOR-CGS operations.…”

“…The water injection rate increased from 700 to 1500 and from 2500 to 10000 barrels of water per day for the Wirt and Post Oak projects, respectively. 27,29,30 Oil production also increased remarkably and continuously from 15 to a peak of 420 and from 300 to 870 barrels of oil per day for the Wirt and Post Oak projects, respectively. Carbonated water was also injected into over 300 wells, mostly in Kansas, Texas, and Oklahoma to improve injectivity.…”

“…Carbonated water was also injected into over 300 wells, mostly in Kansas, Texas, and Oklahoma to improve injectivity. 29,30 Unfortunately, the economic viability of the process for these projects declined due to the expensive CO 2 acquisition from (2) Higher concentrations of CWI did not provide substantial advantages compared to lower concentrations. (3) CWI proved to be effective in improving well water intake rates and serving as a successful well stimulation technique.…”