As the industry recovers, E&P companies

focus on cost per treatment for chemicals.

Today’s well completion technology—and its impact on future production—brings challenges through longer laterals, additional fracture stages, high-viscosity friction reducers, changing proppant quality, reservoir parent-child well interference and strung out completion schedules as full field development expands across the oil patch.

Those challenges also include the efficacy of wellsite chemical programs to protect tight formation reservoirs from microbial activity that can accelerate corrosion and degrade hydrocarbon quality and sour reservoirs.

“We are seeing an increase in customers looking for a solution that provides longer term protection in the downhole environment,” said Christina Pampena, regional marketing manager for Europe and North America, The Dow Chemical Co. “Now that you have more stages per frack and are holding off on initial production, you need something that provides bacterial control in the downhole environment that lasts for weeks to months.”

Microbial chemical treatment represents about one-half of 1% of well costs. In aggregate, the North American onshore oil and gas microbial market exceeds $200 million annually and is growing at a 5% compound annual growth rate.

In the scramble to bring capital efficient production online during the downturn, E&P companies focused on the lowest unit cost in well construction.

“Now that we’ve seen oil prices rise, there is more focus on the total cost to treat program as opposed to just looking at lowest unit cost,” said Joe Ferrara, global industry leader for energy and water at The Dow Chemical Co.

Field testing indicates traditional chemical treatment programs, whether in tight formations or conventional oil and gas, did not always translate to new well construction practices. For example, oxidizing biocides, such as chlorine dioxide, provide an effective surface treatment. However, when treated water went into contaminated fracture holding pits, it came out as contaminated as it was before the original treatment.

There has been a recent rise of regional sand as proppant adds to the challenge.

“We are seeing a lower quality proppant, which means there is higher opportunity for that proppant to provide an additional source of contamination,” Pampena said. “Chemistries based on surface activity like Quats (quaternary ammonium biocides) or TTPC [tributyl tetradecyl phosphonium chloride] bind to the proppant and lose efficacy. The minute you add water, proppant and a surface biocide into the blender, you lose the efficacy of that biocide.”

Dow’s Microbial Control division addresses water preparation, well decontamination and biocides to protect the reservoir in hostile downhole temperatures with varying acidity along with heterogenous water quality issues including salinity in a full spectrum program from product development through regulatory approval. “New chemistry like THNM [tris(hydroxymethyl) nitromethane] and DMO [dimethyloxazolidine] can be combined with glutaraldehyde that gives you that quick-kill topside and the first two weeks protection from the glutaraldehyde,” Pampena said. “Then THNM and DMO provide months of protection underground.”

Microbial treatment is one area in which E&P companies might not find widely sought cost-reducing solutions through self-sourcing.

“Self-sourcing makes sense for proppant because it is a highly commoditized product,” Pampena said. “It’s very easy for an operator to go directly to the source and pay for it. There is no issue pumping it onsite. For value-added products like biocides or surfactants where it takes a lot of application science and know-how to figure out the right system, I don’t see how E&Ps are successful self-sourcing products.”

Dow’s Ferrara agreed, stating, “The service company is a necessary component of this value chain in order to drive application know-how in addition to the technical knowledge. The operator would struggle in a more specialized environment to make proper selections.”