by Neil Trenaman
September 13, 2016

Water management is a key component of any offshore oil or gas enterprise. It is also one of the most challenging and complex issues facing offshore oil and gas operators today. Some aspects of water management in a typical oil and gas operation can include water needed for use in producing the oil or gas, ballast water necessary for moving the platform up and down, supplying drinking water for employees, and treating and managing wastewater disposal.

The cost and complexity of managing these different water-related tasks poses significant challenges and risks to the operator.

For example, three barrels of water are typically needed to produce every barrel of oil or gas, and that water comprises 98 percent of all produced water generated by petroleum exploration and production. Reducing the amount of water required for oil and gas production, and reusing produced water where possible, can considerably increase the sustainability of an enterprise as well as decrease costs.

Advanced, innovative and intelligent water-management strategies should be selected carefully for any offshore project. For example, some produced water treatment systems use smarter aeration, advanced filtration and chemical-free disinfection to improve the process for making water suitable for reuse or disposal in offshore environments.

Safety

Water management is also about mitigating risk. For example, operators should focus on understanding ocean conditions and weather to minimize worker injury and optimize operational efficiency, ensuring a secure water supply for operations or adequately treating wastewater to minimize any impact on the surrounding environment. Minimizing freshwater use and reducing or recycling wastewater can improve operator profitability and contribute to water conservation.

Smart Water Management

By incorporating innovative water management technologies into their operations, as well as employing advanced health, safety and environmental (HSE) practices, offshore oil and gas operators can reduce costs and positively impact their bottom line. High-quality HSE practices minimize the occurrence of accidents and associated downtime and costs. They also protect the natural environment around a production site.

Smart technology can greatly improve water management and streamline HSE practices. When supported by appropriate training, organizational guidelines and effective leadership, technology can exponentially decrease HSE-related incidents.

Environmental Monitoring

MetOcean surveying and characterization solutions enable the collection and transmission of environmental information. Accurate measurements improve environmental impact assessments and the preparation of contingency plans, operational models and forecasts wherever offshore activities are conducted. MetOcean instrument platforms offer a smart and flexible observation system without the huge cost of a custom solution.

Remote monitoring technology eliminates the need for on-site pump watch. Engine and pump data is collected at frequent intervals and transmitted to a password-protected website. A built-in alarm system warns operators of faults in a pump, which lets engineers know exactly what equipment to bring along when they go to fix the problem. The technology can also monitor emissions from a pump engine, which can indicate problems such as blocked filters. For added security, the website also allows operators to turn off and lock a pump located anywhere in the world.

Produced Water Treatment

Smart water technologies have been designed to effectively meet the demands and challenges of treating produced water in offshore environments. Produced water contains contaminants that must be removed before proper disposal or reuse. Some of the impurities or substances likely to be found in produced water include oil, naturally occurring radioactive materials (NORM), waxes, greases, sand, scales, dissolved salts, carbon dioxide (CO2) and hydrogen sulfide (H2S) gases, hydrocarbons, production chemicals, and various metals.

The treatment of produced water will differ according to the intended disposal method or reuse purpose. Closed vessel ultra-violet (UV) systems, advanced filtration, chemical-free disinfection, cyclonic separation, flotation and evaporation are among the commonly used treatment techniques. Cost-effective, efficient and safe treatment of produced water changes a waste product to a beneficial-use commodity.

Case Study

The “Polarled Pipeline,” a 482-kilometer pipeline that will transport gas from the Aasta Hansteen field in the Norwegian Sea to western Norway, is the first pipeline to transport Norwegian Gas infrastructure across the Arctic Circle. Because of the large diameter and length of the pipeline, Halliburton needed a high volume of seawater for flushing and maintenance of the pipeline. The gas pipeline will be laid in water depths of up to 1,265 meters and will be the first gas pipeline measuring 36 inches in diameter to be installed at such depths. The booster pumps required to feed the main high-pressure piston pumps have to be diesel-driven and self-priming. A pump manufacturer provided Halliburton with four skid-mounted pumps. The pumps came equipped with the required automatic safety system and certified lifting assemblies. Special paint was also applied to the structure to combat the salty, corrosive environment. The Polarled Pipeline was completed in September 2015. The gas processing plant in Norway’s Nyhamna area will be ready to receive Aasta Hansteen gas in 2017.