Ethyl Lactate: An Innovative Booster for Acid Fracturing in Oil Exploitation

In the context of the continuously climbing global energy demand, oil, as a crucial energy resource, the advancement of its extraction technology plays a pivotal role in meeting energy supply and ensuring economic development. However, with the continuous exploitation of conventional oil resources, the oil extraction industry faces numerous severe challenges.

To address these challenges, oil extraction technologies are constantly innovating, among which acid fracturing technology has become one of the key means to improve oil and gas recovery. Acid fracturing technology injects acid into the formation to dissolve the minerals in the rock and form fractures, thereby improving the permeability and flow channels of oil and gas, enabling oil and gas to flow more smoothly to the wellhead. In this process, ethyl lactate, as an important additive, plays a unique and crucial role. It can not only improve the performance of the acid fracturing fluid but also effectively enhance the effect of acid fracturing, bringing new breakthroughs and development opportunities to the oil extraction industry. This article will deeply explore the specific role of ethyl lactate in the acid fracturing part of oil extraction, revealing the scientific principles and application values behind it.

Multiple Roles of Ethyl Lactate in Acid Fracturing

(1) Optimizing Fracture Propagation

In acid fracturing operations, the effective propagation of fractures is of great significance for oil and gas extraction, and ethyl lactate plays a key role in this process. It can significantly reduce the fracture pressure of the rock, mainly due to its unique chemical properties. The molecules of ethyl lactate can interact with the minerals on the rock surface, weakening the forces between rock particles. When the fracturing fluid is injected under high pressure, this weakening effect makes the rock easier to be fractured, thus reducing the required fracture pressure.

(2) Enhancing Acid Transfer and Reaction Efficiency

During acid fracturing, the full contact and efficient reaction between the acid and the rock are the keys to achieving an increase in formation permeability, and ethyl lactate plays an indispensable role in this regard. It can effectively improve the transfer speed and uniformity of the acid in the fractures, thanks to its good solubility and surface activity. Ethyl lactate can be fully miscible with the acid, reducing the surface tension of the acid, enabling the acid to flow more smoothly in the fractures. At the same time, it can also reduce the friction between the acid and the fracture wall, further increasing the transfer speed of the acid. Experimental data show that in the acid fracturing fluid containing ethyl lactate, the flow rate of the acid in the fractures is approximately 25% higher than that in the ordinary fracturing fluid. This means that the acid can reach all parts of the formation more quickly, fully contact with the rock, thereby improving the efficiency of acid fracturing.

(3) Improving Proppant Distribution and Stability

After acid fracturing is completed, the reasonable distribution and stable support of proppants are crucial for maintaining the open state of fractures and ensuring the smooth flow of oil and gas, and ethyl lactate plays an important role in this aspect. It can improve the distribution of proppants in the fractures, making the proppants more evenly dispersed in the fractures.

Ethyl lactate has good wettability, which can reduce the interfacial tension between the proppant and the fracturing fluid, making the proppant easier to disperse in the fracturing fluid. At the same time, it can also reduce the mutual aggregation of proppants and avoid the phenomenon of proppant accumulation. During the actual construction process, through the monitoring of the proppant distribution in the fractures, it is found that after using the fracturing fluid containing ethyl lactate, the proppant distribution in the fractures is more uniform, and the proppant coverage rate is approximately 20% higher than that of the traditional fracturing fluid. This uniform distribution can effectively improve the fracture support effect, prevent local closure of the fractures under pressure, and ensure the smooth flow channels of oil and gas.

In the future, with the continuous progress of technology, ethyl lactate will not only further consolidate its position in the exploitation of conventional oil and gas reservoirs but also play a more crucial role in the exploitation of unconventional oil and gas resources such as deep – sea oil and gas, shale gas, and coal – bed methane. It will bring more technological innovations and development opportunities to the oil extraction industry, become an important force promoting the continuous progress of oil extraction technology, and make indelible contributions to the stable and sustainable development of the global energy supply.