A New Technology on Formation Fracturing: LPG Anhydrous Fracturing
Liquefied petroleum gas (LPG) anhydrous fracturing technique, with mixture of propane replacing water in fracturing, compresses propane to a gel state, which was then pressed into rock crevices together with the proppant. This technology has long effective fractures and strong proppant suspension ability. It is non-polluting and adapt to a wide range of reservoir types. It can achieve zero carbon dioxide emissions and closed-loop cycle with 100% recycling and many other advantages.
Practice shows that, in extending effective fracture length, only 20 to 50% fractures in conventional hydraulic fracturing contribute to actual production while those produced by LPG anhydrous fracturing all belong to effective fracture length. So the application of this technique can obtain higher yields, increasing the ultimate recovery by 20 to 30%. In improving proppant suspension capability, LPG with higher viscosity can suspend proppant completely, avoiding proppant deposition due to the lower viscosity of common fracturing fluid and making the production formation fully open to achieve better fracturing result. On the environment protection, compared with hydraulic fracturing fluid, LPG fracturing fluid has a lower surface tension, lower viscosity, lower density, better integration with hydrocarbons in reservoir and better reusability. That is why it can get more effective fractures, greater initial production, better environmental performance and longer life of oil and gas production. In terms of saving water, LPG fracturing without water consumption can save water by around (1 ~ 4) X 10m3 per well.
Up to now, the job record og LPG anhydrous fracturing technique is as follows: 10 level fracturing in horizontal well with horizontal segment length 1,188.72 m, proppant amount consumption 453.59 t, maximum operating pressure 8.998 gPa; maximum pump speed 7.95 / min, proppant concentration 0.96 g / ma. This technology has been applied to more than 40 different reservoirs, with maximum vertical depth reaching 4,008.12 In and formation temperature ranging from 15 to 135 ℃. Currently, Chevron, Husky, ECG, Devon Energy, Paramount and other international oil companies have applied LPG anhydrous fracturing in production.
As a new technique in development, the application of LPG anhydrous fracturing is currently from some single wells to great basins or blocks. In the future it may also play an important role in the oil and gas fields with specific needs.
For more information, please visit DICO's official website: www.dicoenergy.com