People around the world use gasoline for transportation every day. For consumers and businesses, the most noticeable thing about each fill-up is its fluctuating price, but they often know little about the complex process of extracting crude oil and refining it into motor fuel. For example, few are aware that crude oil only accounts for one-tenth of what is extracted at the typical well site. The other 90% is toxic wastewater.
This creates significant friction for the business. Operational impacts include the need for increased scaling in wells, more corrosion of equipment and more energy consumption. Having so much wastewater also means less treatment capacity for the oil that brings revenue in the first place. The operational impacts also cause sustainability problems. Processing large volumes of water requires more energy consumption and creates additional CO2 and NOx discharges. It also requires the use of large volumes of biocides, corrosion inhibitors, and other chemicals.
For oil and gas companies, these operational and environmental impacts also create enormous pressure on the bottom line. As per industry sources, it is estimated that 45% of capital investment in the typical well, and 65% of its operating costs, go toward the management of toxic wastewater. These massive financial costs result in a significant increase in the lifting cost of a unit of oil or gas.
Significant Improvement Is Possible
Even many inside the industry assume that the wastewater to crude oil (90% : 10%) ratio is fixed and cannot be improved. The fact is, making the overall operation more efficient reduces wastewater and brings down per-unit production costs by up to 23%.
This overall potential cost reduction can be the result of efficiencies gained throughout the process, as shown in Figure 1. By optimizing operations at the progressing cavity pumps (PCPs), organizations can realize a 10% reduction in energy costs and reduce chemical use at the wellhead by 7%. By having to process less water, the first-stage and second-stage production separators can see further reductions in both power consumption and chemical use, and the emulsion breaker also requires less energy. Finally, less volume means huge savings in the cost of treating, transporting, and disposing of the wastewater. This includes 40% less chemicals used in the treatment process and 13% less in the pipeline; and a 27% reduction in power consumption for treatment and a 40% reduction for disposal.
The reason that such significant savings are possible is because of inherent inefficiencies that have remained unaddressed in the drilling process for decades. These points of friction are so ingrained at many organizations that even longtime veterans may be skeptical of resolving them. The problem is that each element of the very complex process of drilling has historically been managed in a silo. To optimize operations, improve efficiency and reduce the volume of wastewater, organizations must take a holistic approach, using automation to optimize each step in the process and minimize waste.