【本周专题：压裂增产】支撑剂更新永不止步，增产降本唾手可得（下）

ADVANCED PROPPANTS CAN REDUCE COST PER BOE

Today’s oil and gas industry continues to face many challenges during well completions, some of which include increasing oil production, reducing unwanted formation water production, and increasing microfracture stimulation. New resin technology has helped operators to reduce cost per boe beyond the benefits of traditional resin-coated proppants.

Increased oil production. An operator objective is to increase oil production while reducing the cost per boe. One proven way to accomplish this is by using advanced proppant technology, designed specifically to increase oil production over traditional proppants. Hexion’s OilPlus proppants have advanced resin technology that has yielded years of enhanced oil production in all the major plays of North America. They provide higher oil flowrates compared to traditional resin-coated proppants, ceramics, and uncoated frac sand.

The company’s patented technology increases proppant pack relative permeability to oil. When traditional proppants are used, water adheres to their hydrophilic surfaces, blocking pathways for oil and gas to flow. With the new proppant technology, water does not cling to the surface of the proppant. This allows a clear path through the proppant pack, resulting in increased flow of hydrocarbons, compared to traditional proppants.

The company’s patented technology increases proppant pack relative permeability to oil. When traditional proppants are used, water adheres to their hydrophilic surfaces, blocking pathways for oil and gas to flow. With the new proppant technology, water does not cling to the surface of the proppant. This allows a clear path through the proppant pack, resulting in increased flow of hydrocarbons, compared to traditional proppants.

If the operator had used the new proppants on the other wells, they would have yielded an additional $3.33 million in revenue. The completion engineers responsible for these wells moved to other operators and continue to pump these proppants, due to the success they experienced in the Permian basin. They continue to see financial value in utilizing the new proppant technology through all market cycles.

Reducing formation water production. The formation water produced after hydraulic fracturing is a challenge to most operators in North America. The disposal of unwanted formation water increases the cost of boe per well. In the U.S., formation water produced averages around 5 to 6 bbl of water for every barrel of oil produced. The Permian basin, for example, produces 6 to 8 bbl of water per barrel of oil. And because this water is full of minerals, petroleum residue, and salt, producers must dispose of the water in a safe and environmentally responsible manner.7

The rise in completion activity has led to an increase in water intensity and formation water production. The basin’s saltwater disposal well (SWD) capacity is facing heavy constraints in key areas. As SWDs—that are near a well, that is producing high volumes of produced water—reach capacity, operators have to transport water to more distant locations for disposal. This has led to a material increase in water disposal costs. Presuming that the price of oil continues to stabilize, it is estimated that water production in the Permian basin could increase by as much as 50 MMbbl each month. If production increases by this amount, approximately 70 MMbbl of produced water would need to be diverted from current disposal facilities to new facilities, or be diverted for reuse.

Without compromising oil and gas production, Hexion’s AquaBond proppants have advanced technology specifically designed to reduce formation water production, compared to traditional proppants. The lower water production results in reduced cost per boe, per well. The innovative resin chemistry of these unique proppants alters the relative permeability of the proppant pack for preferential flow of hydrocarbons over water. The water-reducing properties are part of the chemistry of these resin-coated proppants, which provides water reduction benefits over the life of the well.

Reduction in produced water case study. In the Granite Wash formation of Oklahoma and Texas, production from one well, that used a 23% AquaBond proppant tail-in, was compared to three offset wells that used 100% uncoated frac sand. Total proppant volumes, depths, and lateral lengths were all similar, and the wells were all completed for the same operator in the same time period. Over nine months, the well with the new proppant produced approximately 26,000 fewer barrels of water than an average of the offset wells. The well also produced more than three times the boe than the average of the offsets.

A new innovative solution, kRT 100 proppant, was developed to stimulate microfractures, while providing all of the advantages of a resin-coated proppant. The resin coating supports the intended use of 100-mesh grains within the fracture network. These proppants now provide all of the benefits of a resin-coated proppant, such as mitigating proppant flowback, limiting proppant fines, and reducing proppant embedment, compared to uncoated frac sand. Because these small proppants bond in the microfractures, they also keep proppant rearrangement from occurring. A bond strength test showed that these proppants bonded into a unified proppant pack at 130?F, while uncoated frac sand does not form bonds.

CONCLUSIONS

Operators today are focused on optimizing completions to further drive down the cost per boe. The vast majority of hydraulic fracturing jobs are using uncoated frac sand. While these wells can produce sufficiently, well economics could be improved by utilizing resin-coated proppants. The initial cost-savings of uncoated frac sand are negligible, compared to the long-term benefits of increased production that can be seen from resin-coated proppants. Production declines clearly show that the continued stress on uncoated frac sand causes the grains to fail over time. Conversely, resin-coated proppant technology is proven to improve EUR.

Traditional resin-coated proppants can provide many benefits over uncoated frac sand, such as mitigating proppant flowback, along with providing high porosity and fracture conductivity. However, advanced resin-coated proppants can offer additional solutions over traditional proppants, such as increasing oil production, reducing unwanted formation water, and propping microfractures with grain-to-grain bonding. Pumping proppants with innovative technologies can improve well production and reduce cost per boe, compared to traditional proppants.