Water Conservation through Power Cogeneration.
The oil and natural gas industry practices environmental protection and water conservation as a part of many of their operations. These practices are good for business, of course, but they also help protect and conserve resources. As an example, it is common practice for oil refineries to employ "cogeneration". That means that excess energy from normal operations, either in the form of steam or heat, can be used to create additional electrical power. This increases efficiency, and can lead to water conservation because water requirements for cogeneration are often less than for the same power generated by coal-fired boilers or steam-condensing turbines. The electrical energy produced, whether it is used by the refinery (reducing the electrical requirements that might be placed on the power company) or sold to the power company (adding to the available electrical power), uses less water because of the more efficient system. For example, a 6 million-gallon-per-day (MGD) water intake at a refinery might support cogeneration of 525 megawatts (a megawatt, or MW, is one million watts), using gas turbines, versus more than 14 MGD to generate 525 MW by coal-fired boiler with condensing turbine in a commercial power plant. Using half the water in creating the same amount of electricity is a valuable savings for the environment, the consumer and the refinery. It is how good business can benefit everyone.
Water Conservation and Natural Gas Production.
In arid desert regions, water conservation becomes a high priority for business, operational, and environmental reasons. For example, one API member with natural gas production operations in Southeastern New Mexico reported in its Sustainable Global Performance report that it is using innovative water treatment technology to conserve fresh groundwater. Water treatment technology is being used to remove hydrogen sulfide gas that is entrained in water that is produced in conjunction with natural gas production. The treated water is then used in the company’s drilling operations, thereby reducing the amount of fresh groundwater that has to be used. This use of treatment technology provides an innovative solution for beneficially reusing produced water. Before using this water treatment technique, the company had to re-inject all waters produced during its natural gas production into a non-producing formation for disposal. During 2000, this water treatment system reduced the company’s use of fresh groundwater by about 4 million gallons. This initiative is helping to ensure that fresh groundwater is available for future residential and agricultural needs in southeastern New Mexico.