Fracture products

Sydansk, R.D., Xiong, Y., Al-Dhafeeri, A.M., Schrader, R.J., Seright, R.S., 2005. Characterization of partially formed polymer gels for application to fractured production wells for water-shutoff purposes. SPE Production Facilities 20 (3), 240-249. 

Flow-Induced Chain Scission. If the chains are overstretched, that is, e increases along the plateau in Figure 2, they will eventually break 12, 13). The molecular weight of the fracture products can then be determined by the method just outlined. Thus, through our technique we can both break chains in a controlled manner and analyze the resulting fracture products within the same apparatus, this double capacity enabling a systematic study of the flow-induced chain fracture. The principal results, to be of consequence later, are as follows ... 

Tertiary phase, when strain rate increases again, leading to fracture, product failure. 

Each hydraulic fracturing product is a mixture of chemicals or other components designed to achieve a certain performance goal, such as increasing the viscosity of water. Some oil and gas service companies create their own products, but most purchase these products from chemical vendors. The service companies then mix these products together at the well site to formulate the hydraulic fracturing fluids that they pump underground. 

Flydraulic fracturing products are comprised of a wide range of chemicals. Some are seemingly harmless, such as sodium chloride (salt), gelatin, walnut hulls, instant coffee, and cifric acid. Others, though, could pose severe risks to human health or the environment. 

Chemical Components Apipearing Most Often in Hydraulic Fracturing Products (2005-2009)... 

The oil and gas service companies used hydraulic fracturing products containing 29 chemicals that are (1) known or possible human carcinogens, (2) regulated under the Safe Drinking Water Act for their risks to human health, or (3) listed as hazardous air pollutants (HAPs) under the Qean Air Act. These 29 chemicals were components of 652 different products used in hydraulic fracturing. Table 7.4 lists these toxic chemicals and their frequency of use. 

The vast majority of these SDWA-regulated chemicals were the BTEX compounds—benzene, toluene, xylene, and ethylbenzene. The BTEX compounds appeared in 60 hydraulic fracturing products used between 2005 and 2009 and were used in 11.4 million gal of hydraulic fracfuring fluids. The Department of Healfh and Human Services, the International Agency for Research on Cancer, and fhe USEPA have defermined that benzene is a human carcinogen (ATSDR, 2007). Chronic exposure to toluene, ethylbenzene, or xylene can also damage the central nervous system, liver, and kidneys (USEPA, 2012b). 

Shallow water carbonate (reefs carbonate muds) Reservoir quality governed by diagenetic processes and structural history (fracturing). Prolific production from karstified carbonates. High and early water production possible. Dual porosity systems in fractured carbonates. Dolomites may produce H S. 

Carbonate rocks are more frequently fractured than sandstones. In many cases open fractures in carbonate reservoirs provide high porosity / high permeability path ways for hydrocarbon production. The fractures will be continuously re-charged from the tight (low permeable) rock matrix. During field development, wells need to be planned to intersect as many natural fractures as possible, e.g. by drilling horizontal wells. 

Horizontal wells have a large potential to connect laterally discontinuous features in heterogeneous or discontinuous reservoirs. If the reservoir quality is locally poor, the subsequent section of the reservoir may be of better quality, providing a healthy productivity for the well. If the reservoir is faulted or fractured a horizontal well may connect a series of fault blocks or natural fractures In a manner which would require many vertical wells. The ultimate recovery of a horizontal well is likely to be significantly greater than for a single vertical well. 

The mechanical performance of equipment is likely to deteriorate with use due to wear, corrosion, erosion, vibration, contamination and fracture, which may lead to failure. Since this would threaten a typical production objective of meeting quality and quantity specifications, maintenance engineering provide a service which helps to safely achieve the production objective. 

Computation of the depth of a crack taking into consideration its length effect end the product thickness allowing to reduce the complementary error while measuring short cracks and fractures with their depth more then half the thickness from 20 - 100% to 2 - 5%,... 

For primary insulation or cable jackets, high production rates are achieved by extmding a tube of resin with a larger internal diameter than the base wke and a thicker wall than the final insulation. The tube is then drawn down to the desked size. An operating temperature of 315—400°C is preferred, depending on holdup time. The surface roughness caused by melt fracture determines the upper limit of production rates under specific extmsion conditions (76). Corrosion-resistant metals should be used for all parts of the extmsion equipment that come in contact with the molten polymer (77). 

Like other thermoplastics, they exhibit melt fracture (32) above certain critical shear rates. In extmsion, many variables control product quaUty and performance (33). 

In instances where test bores have been completed, it may sometimes be possible to predict the general locations of productive fractures. When these are encountered by surprise, however, the appropriate adjustments in the drilling strategy must be implemented rapidly, slowing the progress of the drilling operation and increasing the costs. 

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