While storage and logistics are critical elements of the viability of water reuse, if the water chemistry is not fit for gel fracturing formulations, it will not matter how much is stored in centrally located impoundments. A recent webinar discussed current technologies to enable reuse of produced water in gas and oil shale developments.
Produced-water (PW) and flowback-water (FW) quality in shale projects is influenced not only by the formation, but also by the fracturing fluid introduced to the formation during hydraulic stimulation. The water produced by shale wells can contain suspended solids, dissolved solids, organics that include hydrocarbons and residual-fracturing-fluid chemicals, and bacteria. This paper describes functional water-treatment steps that target the most common removal of suspended solids and oil or condensate from PW and FW for recycling or disposal operations. Rapid industry expansion into shale-gas and -oil development requires a reconsideration of how water management and technology are applied. What may be acceptable and fit for purpose at a smaller scale may become unsatisfactory when the business grows significantly.
Kim, CN (Hyundai Heavy Industry) | Hwang, HW (Hyundai Heavy Industry) | Kim, SE (Hyundai Heavy Industry) | Park, SM (Hyundai Heavy Industry) | Park, JS (Hyundai Heavy Industry) | Kim, TJ (Hyundai Heavy Industry) | Kim, YR (Hyundai Heavy Industry) | Kim, YH (Hyundai Heavy Industry)
Offshore development project are facing significant challenges from current market environment. Due to current low price of oil and gas, the development of natural reservoirs on offshore may not be attractive. However, the demand of natural gas will gradually increase because natural gas is relatively clean source comparing to the other fossil fuels and the demand of clean energy is growing due to environmental change.
In this regards, Near Shore FLNG is becoming one of the most economical solutions as the unit is equipped with essential liquefaction process, storage as well as offloading facility. That is, comparing to typical deepwater FLNG application, expensive components are not required such as the turret, complex pre-treatment system and self-generation of utilities, plus logistics such as refrigerant supply are better.
The purpose of this paper is to introduce the optimized process of Nearshore FLNG system comparing typical FLNG. To illustrate the optimized process, at first, target area is defined as North America. The reason why North America is selected is because of the potential of future projects and shale gas revolution. The gas composition is defined by reviewing 1,200 shale gas reservoirs in North America and considering the hydrocarbon gas is typical pipeline gas which needs to meet Pipeline Gas Spec requirement. Topside process is reviewed to find optimized options and process model has been built to check feasibility. Analysis is made on several technical optimized options as below.
Optimized Liquefaction system
Optimized Condensate System
Remove Deethanizer and Ethane make up column
Optimized Heating Medium system
Optimized Produced Water Treatment System
Finally, this paper provides several options with reducing several facilities and optimizing process which will reduce CAPEX/OPEX.
The torrent of dirty water coming out of almost every American oil well is the next big bet for a former fund manager for billionaire Paul Allen. Getting rid of wastewater from onshore wells has become an increasingly costly problem for oil producers as US crude output surged in recent years, especially in the new shale fields from Texas to North Dakota. Drillers typically get about seven barrels of water for every one of oil, and some struggle to deal with the overflow that is mostly sent by truck to disposal sites miles away. David Capobianco, a former managing director for Allen’s Vulcan Capital, is trying to change that by building pipelines to get wastewater out. His newly formed WaterBridge Resources aims to be a water-management company for oilfields.
OriginClear’s Electro Water Separation technology treats water prior to reverse osmosis that typically contains a maximum of 3,000 ppm of hydrocarbons. The company agreed to a pilot test of a Sinopec-operated shale gas site in the Shangdong province. A provider of water treatment solutions, OriginClear, has partnered with a regional organization in the Chinese province of Shandong for remediation of a shale gas site operated by the government-owned Sinopec group, Asia’s largest oil and gas company. The two companies are currently in the midst of a pilot testing period at Sinopec’s FuLing shale gas site in Chongquing, a city in southwestern China, that is intended to qualify OriginClear’s Electro Water Separation (EWS) technology for integration into a multistage process designed to treat hydraulic fracturing and flowback water for on-site reuse. After inserting them into the wastewater and applying a low current, the electrodes form microsized hydrogen and oxygen bubbles that attach to suspended solid matter and rise to the surface, forming a layer of solids that can be easily removed.
Electrochemical technologies are a promising alternative for the Oil Industry, for the treatment of formation water containing organic and inorganic contaminants. The main advantages of these technologies include environmental compatibility, versatility, energy efficiency, health & safety and selectivity. However, the effectiveness of the electrochemical approaches depends significantly on the electrode material and the cell parameters. Recently, BDD electrodes have shown a growing interest due to their unique ultra-wide electrochemical window with highest O2 and H2 over-potentials.
The current approach based on the application of boron doped diamond (BDD) electrode to treat electrochemically production water (PW) coming from a heavy oil field, was investigated in one-compartment electrolytic batch cell. Formation water is increasing more and more with the depletion of pressure and the age of many oil and gas fields. This formation water is characterized by high initial chemical oxygen demand (COD) due to their high level of organic content. Proper elimination of the high COD content from PW to be re-usable water streams for beneficial purposes such as irrigation water or correct disposal is becoming increasingly important for an environmental and human health in the Oil Industry.
The influence of primary settling treatment step and several operating parameters such as applied current density, supporting electrolyte (NaCl or Na2SO4), agitation and temperature on the COD removal efficiency from PW were investigated and the corresponding energy consumption value was also evaluated. The estimated COD removal efficiency was achieved with and without settling step between 90 and 100 % within treatment time of 5h - 7h by using applied current in the range of 5 - 12.5 mA/cm2, but the minimum absolute value of COD for the resulting water with and without settling step was achieved to be less than 0.09 mg/l and 75 mg/l, respectively by adding 3.5 g/l NaCl. However, the energy requirement for high removal efficiency without adding NaCl was 2.5 more than with NaCl into PW. Adding NaCl into PW decreases the energy consumption and increases the oxidation efficiency by promoting the electro-generation of active chlorine species in addition to hydroxyl radical. On the other hand, only 67 % removal efficiency of COD was achieved by adding 5.1 g/l Na2SO4 into PW which affect negatively the COD removal efficiency compared to PW without any supporting electrolyte.
The integration of electrochemical treatment step based on BDD electrodes after settling primary step, which is commonly used in industry, as a novel secondary treatment step will create a hybrid stable electrochemical system combining different electrochemical removal mechanism by BDD electrode as anode and cathode such as electro-oxidation, - reduction [
Limited disposal options and/or water scarcity have led the oil and gas industry in some shale plays to establish goals for minimizing the use of freshwater for drilling and completion activities by maximizing the recycle of wastewaters generated from exploration and production (E&P) activities. Many operators have established a goal of 100 percent recycle for their development activities. Eureka Resources, LLC (Eureka) has developed a business model which gives oil and gas operators a sustainable choice for recycling oil and gas wastewaters when water is scarce or disposal options are limited. The business model is based on operation of centralized facilities that targets recovery of useable byproducts. There are many challenges associated with operating a centralized oil and gas wastewater treatment system that includes pretreatment, crystallization, biological treatment, ion exchange and reverse osmosis unit processes. This paper summarizes the challenges and lessons learned during startup and shakedown of a thermal treatment (crystallization) based model.