Introduction Flow assurance of hydrocarbon streams in subsea systems, such as pipelines, is a very important subject in the oil and gas industry. It is diverse and encompasses many branches of engineering disciplines. Flow assurance involves handling many solids deposits from hydrocarbon fluid streams that can form in subsea flow lines. Some of the flow assurance risks in subsea pipelines include gas hydrates, slugging, corrosion, reservoir souring, wax, scales etc. Among these flow assurance risks, hydrate formation is of major concern in the oil and gas industry. Hydrates are solid-crystalline compounds formed when water come into contact with light hydrocarbons such as methane, ethane and propane under thermodynamically, usually high pressure and low temperature. Hence, hydrate readily form in flow lines transporting hydrocarbon streams along with produced water often lead to pressure drop in flow lines and eventually plug flow. Nowadays, offshore oil and gas projects have been moving further into the deeper sea where hydrates are significant problems due to favourable high pressure and low temperature conditions. As a result, deep water flow assurance has become an increasingly major concern for oil and gas industry. The potential formation of hydrates in gas production is of great importance in connection with pipeline transportation of hydrocarbon liquids and with the production of fluids from natural gas or gas condensate reservoirs. Hydrate formation during oil and gas production can plug production facilities and cause a long-term problem to oil and gas project. According to Dholabhal et al. (1993), the accumulation of hydrates is common in the horizontal sections and around fittings could lead to disastrous pipeline blo... ... middle of paper ... ...nd Control of Natural Gas Hydrates”. European Offshore Petroleum Conference and Exhibition, London, Society of Petroleum Engineers, Paper 8137, October 24-27 1978. 31. Yousif M.H. “The Kinetics of Hydrate Formation”. Annual Technical Conference and Exhibition, New Orleans, LA, USA, Society of Petroleum Engineers, Paper 28479, September 25-28 1994. 32. Jassim E., Abdi M.A., and Muzychka Y. A CFD-Based Model to Locate Flow Restriction Induced Hydrate Deposition in Pipelines. Offshore Technology Conference, OTC 19190. 2008 33. Lysne D. “An Experimental Study of Hydrate Plug Dissociation by Pressure Reduction” Ph.D. Thesis, Norwegian Institute of Technology, University of Trondhiem, 1995. 34. Viana F., Garcia-Hernadez A., and Supak K. “Hydrate Formation and Slugging Assessment of an Offshore Gas Field”. Pipe Simulation Interest Group annual meeting, (PSIG 1327). 2013
Gas in shale formations are“low in permeability,” making it very tedious to extract, but with the increase in technological knowledge in fracking and horizontally drilling into shale beds, the vast reserves of natural gas resource could be extracted (4). Fracking is a large industrial operation that boost the “productivity of a oil or gas well” (5). It is a process by which, under very high pressure, a mixture of water, chemicals, and sand, are pumped into shale formations that causes fractures in the rocks to open wider or create new fractures that would allow otherwise trapped oil and gas to flow into the wells (6).
In order to understand the obsidian hydration dating method, a model that can demonstrate the process of glass hydration under a certain range of environmental conditions is needed. To implement this, the nature of the concerned materials i.e. glass and water should be adequately known so that the interaction between them can be predicted on the basis of the properties of each substance (Stevenson et al. 1998). There is no consensus among archaeologists and geochemists on how best to model hydration rates. They have long debated on how hydration-rind thickness could tell us about time. The confusion seems to be based on two points. First, after hydration begins, water is no longer reacting with the pure glass. Rather it reacts with an already hydrated layer. The classic diffusion model breaks down at this point. Second, the different variables that determine the hydration rate are mutually interacting. Several researchers have observed a shift from classic diffusion between hydration-rind thickness and time to a linear relation, based on changes in pH. In turn, pH, in a closed system, is influenced by how long the hydration has occurred (Tremaine 1989). As alkali ions leach into solution and are replaced by hydrogen or hydronium ions, the pH of the solution will increase (Bra...
Ever since the process of hydraulic fracturing—or fracking—made its entrance to the oil industry, issues and problems surrounding the process have become a common occurrence. Fracking is the controversial process of horizontal drilling (see fig. 1), where millions of gallons of water mixed with sand and chemicals are pumped deep into an oil well to extract natural gas from the earth’s crust (Ehrenberg 20). This practice has even been banned in some places (see fig. 1). The methane that comes out of the earth and the water used—called fracking fluid—has the potential to cause problems with local ground water supplies. Whether or not fracking is the cause of these problems, concern should be observed during the fracking process to reduce the chances of water contamination among residential areas.
Osborn, S. G., A. Vengosh, N. R. Warner, and R. B. Jackson. "Methane Contamination of Drinking Water Accompanying Gas-well Drilling and Hydraulic Fracturing." Proceedings of the National Academy of Sciences 108.20 (2011): 8172-176. Print.
A reservoir is considered as a compaction drive is when the pore volume contraction takes prominently to overall expansion while the reservoir is saturated. This drive is supplemented by solution gas drive and may or may not by water/gas cap drive. This reservoir acts like their non-compaction counterparts except that they exhibit enhanced recoveries. For example, the oil recovery will be greater for a solution gas drive by which the compaction drive will act like a normal solution gas drive reservoir. This is because of the direct consequence of the extra rock expansion that compaction drive reservoirs actually have. Due to the extra compaction, some production occurs. For instance, the permeability may decline, fracture may happen and subsidence but all there problems are manageable and the result of compaction is very favorable.
The collected data indicated that the formula of the hydrate is CuSO4· 5H2O. In order to find this formula, we had to first calculate the mass of water lost from the hydrate. So we subtracted the mass of
Hydraulic fracturing, having been patented in 1949 has been the caveat by which one third of the natural gas in the U.S. is obtained.1 The fracturing process requires millions of gallons of fluid to be driven into the ground at high enough pressures to break up shale and rock and in turn lets out natural gases. The process has been proven to be very successful thus being one of the major contributors to modern day natural gas collecting. Though there are many great aspects to hydraulic fracturing, concerns do arise. What is in this fracturing fluid? Is there ground water being contaminated with rocks and the unknown fluid during this process? The hydraulic fluid is known to contain a variety of additives such as dilute acids,
The process of Hydraulic Fracturing is a process that 90% of natural gas wells in the United States use to extract gas from the ground. The first step in fracturing is digging anywhere straight into the ground Fractures are created by pumping large amounts of fluids at high pressure down a wellbore and into the rock formation. Hydraulic fracturing fluid commonly consists of water, proppant and chemical additives that open and enlarge fractures within the rock formation. These fractures can extend several hundred feet away from the well. The proppants - sand, ceramic pellets or other small incompressible particles - hold open the newly created fractures.
Rock and fluid properties are the building blocks in any reservoir engineering study that lead to the formulation of a successful reservoir management strategy. Sometimes the study involves the estimation of oil and gas reserves based on a simple analytical approach, as demonstrated in this chapter. On a separate note, performance prediction of oil and gas reservoir is done by multidimensional simulation models and robust multiphase. Regardless of the study and related complexity, the reservoir engineer must have a sound understanding of the rock properties involved. What is more important is the knowledge of the variability of rock properties throughout the reservoir and how heterogeneous reservoirs perform in the real world. It is a common observation that rock properties vary from one location to another in the reservoir, often impacting reservoir performance. Some reservoir analyses are based on the assumption that a reservoir is homogeneous and isotropic, implying that the rock properties are nonvariant and uniform in all directions. In fact these conditions are so idealized that are rarely met in the field. Various geologic and geochemical processes leave imprints on a reservoir over millions of years, leading to the occurrence of reservoir heterogeneities that are largely unknown prior to oil and gas production. For example, the occurrence...
The use of hydraulic fracturing has caused many environmental problems in the waters of the United States. Improved drilling and extraction technology used to access low permeability natural gas requires millions of gallons of water and a lot of chemicals that may be toxic to marine life.Many people in both the field of science and the community of everyday concerned citizens about the quickly depleting supply of natural resources in the United States caused by hydraulic fracturing. These natural gases will soon no longer be readily available for use in America. Hydraulic fracturing bases are most commonly found near roads and stagnant waters such as lakes and ponds. These roads can cause water to drain into these open lakes and ponds, which
Yen, C.T. and Yu, Y.H. (1966). Mechanics of fluidization. Chemical Engineering Progress Symposium Series, Vol. 62, pp. 100-111.
The study of flow pipes is extremely important as application of pipe system have been used in variety field in real life. For example, transportation of consumed water, waste water, oil and gas are seemed to be easier after application of pipe system.
Applied Environmental and Petroleum Geology - Groundwater contaminants and remediation techniques, hydrogeologic reports, well core and geophysical log analysis, structure contour maps and subsurface analysis, subsurface stratigraphic correlations of reservoirs and aquifers, basic foundation in characteristics of source, reservoir, and trap rocks for oil/gas
Modifications to the well-known van der Waals-Platteeuw (VDW-P) model (van der Waals and Platteeuw, 1959) led to several thermodynamic models for predicting hydrate formation and/or dissociation conditions. The VDW-P model was derived which was based on the similarity between the hydrate formation and Langmuir adsorption. However, both the mechanisms are different, even if the adsorption mechanism is able to explain the nonstoichiometric feature of hydrates.
From the 1970s to the 1990s, pipelines became far more versatile than before. More pipelines were being used to transport natural gas, such as carbon dioxide for oil recovery and other natural gas liquids for a growing heating industry. Pipelines were being constructed to gather oil and gases more than a mile beneath the bottom of the