bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Thermally Responsive Cement for Heavy Oil Wells
Authors: Tomilina Elena M. , Chougnet-Sirapian Alice , Aboutourkia Wesam 
Published: June 2012

Abstract
Canada’s oil sands are one of the world’s largest hydrocarbon resources. The initial volume of crude bitumen in place is estimated to be approximately 260 billion cubic metres with 11 percent or 28 billion cubic metres recoverable under current economic conditions. Continually improving economics, bolstered by recent higher crude oil prices, has resulted in the International recognition of the vast potential of Canada’s oil sands. Based on publicly announced development plans through to 2015, over C$60 billion could be invested in numerous projects to develop the oil sands.
Various factors have to be considered to select the proper cement for zonal isolation of thermal recovery heavy-oil wells. First the cement should be flexible enough to withstand the stresses which occur when casing expands during the heating up of the well. To reduce these stresses, the cement thermal expansion coefficient should be similar to the thermal expansion coefficient of the casing. Finally, cement mechanical properties should not degrade during the whole steam injection process, i.e. when it is subjected to extremely high temperatures (up to 350 degC) for extended periods of time.
Specifically in Canada, the majority of the steam injection wells are drilled in shallow sandstone formations. This requires the cement to have high flexibility to resist the stresses. Moreover, during steam injection, a reaction between the sandstone formation and the cement sheath may occur, impacting the cement matrix and hence changing its properties.
This paper describes the application of a new thermally responsive cement for zonal isolation of heavy oil wells in Canada. This system is designed to have excellent strength, flexibility and thermal properties even upon interaction with sandstone formations. It minimizes the mechanical stresses exerted on the cement sheath during steam injection, thus reducing the risk of loss of well integrity. The numerical simulations performed with these long-term material properties (six months of exposure to 350 degC) for typical Canadian heavy oil wells conditions predict reliable and durable zonal isolation under these extreme conditions. These simulation results are confirmed by several field applications in wells which have not leaked after months of steam injection.
The Benefits of Multiphase Flow Meters in SAGD for Production Optimization and Allocation Measurements
Authors: Graham John , Olson Jeff , Pinguet Bruno , Abraham Anson 
Published: June 2012

Abstract
Steam Assisted Gravity Drainage (SAGD) production is a challenging environment where the economics are driven by optimization of the steam injection and oil production. An accurate metering system coupled with downhole pump information is required as is the reduction in physical intervention and operating expenditures.
Suncor’s Firebag team engaged themselves in this challenging endeavor over the last 4 years to build a strategy using multiphase flowmeter (MPFM) to (1) provide a compact and versatile solution for new wells, (2) comply with regulations, and (3) validate the metering performances of the MPFM against the conventional separator.
The goal of this paper is to address the learnings and challenges faced in the MPFM deployment under these high temperature and harsh line conditions. This knowledge sharing is expected to serve as a guideline for future users of this MPFM technology in SAGD applications particularly with Cold Weather Operations, Multiphase Sampling and High H2S environment, also considering Pressure-Volume-Temperature (PVT) Modeling.
From a practical point of view, the qualification, application and benefits of MPFMs in field conditions will be highlighted versus the conventional solution. A particular focus will be placed on the production optimization and reservoir management.
Additionally, the synergy between the downhole pump information and instantaneous MPFM flow rate measurements will be reviewed along with the positive impact on the production optimization. The benefit of the MPFM accuracy and continuous measurement is expected to improve the allocation factors applied to all wells and pads.
Horizontal Well Placement for Heavy Oil Production in Colombia
Authors: Cuadros Jaime , Salamanca Andrey , Amado Nestor , Cuadros Guillermo , Rojas Esteban , Viramonte Jose Maria 
Published: June 2012

Abstract
The success of a horizontal drilling campaign highly depends on the implementation of appropriate well placement procedures to manage the constraints, risks, and uncertainties that may have a negative impact on the overall economy of the project. The magnitude of the uncertainties associated with the horizontal well trajectory and the geology is usually higher than the magnitude of that particular target within the reservoir that would maximize the production. The risk and uncertainty factors can be handled with the use of particular well placement techniques during the planning and execution phases.
In the planning phase, these techniques include proper geological modeling methods and flexible well planning to allow room for changes if unexpected events arise while drilling. During the well execution, procedures should include the use of appropriate technologies to understand in real time the rock properties, the reservoir geometry, and horizontal well position, and, based on this information, to steer the well within the desired geological target.
Girasol field, located in the Middle Magdalena Valley basin in Colombia, is composed of a sequence of sandstone channels that contain heavy oil with gravity ranging from 11 to 13° API. The main targets are five stacked sandstone reservoirs, from 10 to 35 ft thick, located 1,100 to 1,500 ft true vertical depth below surface. The field development included cyclic steam injection applied in horizontal wells to improve the heavy oil mobility. To maximize oil production and improve the cumulative steam/oil ratio, the objective was to place horizontal wells of up to 2,500 ft lateral extension within 3 to10 ft distance from the bottom shale of each reservoir.
The horizontal well placement under this type of scenario required the use of precise horizontal well placement techniques and drilling practices to avoid exits from the predefined geological targets. These techniques relied on the use of deep directional electromagnetic measurements that enabled real-time bed boundary mapping.
This paper presents the main challenges and uncertainties faced for well placement in the Girasol field horizontal drilling campaign, the technical solutions implemented, and the lessons learned in more than 80 horizontal wells drilled.
Study of Thermal Recovery Method of Steam and Flue Gas Combined with Gel Injection
Authors: Feng Qihong , Guo Longfei , Zhang Xianmin , Gao Sunhua , Shi Hongfu , Wu Shuhong 
Published: June 2012

Abstract
Since the production of China offshore heavy oil field, cold production is mainly used for oil recovery. However, it has faced great challenge including declination of oil production, rapid-increasing water cut and sharp cutoff of reservoir pressure. Conventional heavy oil recovery, such as steam stimulation, steam drive, in-situ combustion and SAGD, is not entirely suitable for offshore platform condition (platform space is small). Based on a new portable and convenient gas generator that can produce high-temperature steam, CO2 and N2, a new stimulation treatment is discussed in this paper, which aimed at the characteristic of sharp cutoff of reservoir pressure, combining steam and flue gas stimulation in production well together with injecting weak gel formed by polymer and cross linker in injection well, thus to keep the reservoir pressure to the utmost extent, and obtain maximal recovery.
Numerical simulation study was conducted on the basis of the conceptual model aimed at the recovering mechanism of weak gel injection and steam and flue gas thermal recovery, the mechanism including dwelling and displacement of weak gel, heating and visbreaking of thermal water or steam, solution and miscible visbreaking of CO2, and thermal fluid heating radius enlarging and gas driving effort improvement of N2. On the foundation of mature mechanism, the optimal injection-production technological parameters fit for reservoir development can be estimated by numerical stimulation of several development programs designed for certain reservoir and orthogonal optimizing method. And injection time and rate for weak gel injection preserving pressure are also discussed in this paper.
Enhanced CHOPS Using SuperSump to Reduce Environmental Footprint and Increase Oil Recovery
Authors: Arnold W. A. , Graham R. E. , Wagg B. T. 
Published: June 2012

Abstract
The two key challenges of primary heavy oil production using the process of Cold Heavy Oil Production with Sand (CHOPS) are limited recovery and the environmental footprint. With estimated remaining heavy oil in Western Canada of up to 300 billion barrels there is a significant opportunity for industry. Recovery of this oil using CHOPS is generally limited to 15% maximum brought on by high operating costs due to sand handling and interruption of the reservoir production process due to sand related workovers. The large CHOPS environmental footprint is driven by the significant surface disturbance due to close well spacing, greenhouse gas emissions from the use of heated lease tanks and handling and the long term disposal of produced sand.
Ongoing evaluations show that the SuperSump System has the potential to reduce the environmental footprint and increase recovery of typical CHOPS operations both in new heavy oil fields and in revitalizing existing fields. The technology uses a gravity stable process to drain oil through multiple wells from an upper viscous oil reservoir into a small fit for purpose cavern washed from underlying salt formations. Oil, water, and sand separate in the cavern and clean oil is produced from a single wellbore to surface. The environmental footprint is reduced by eliminating sand handling, reducing lease sizes, and reducing fluid storage and processing on surface. The SuperSump technology also has the potential to reduce operating costs, allowing increased recovery by prolonging the economic well life as production rates decline. In addition, early well failures due to sudden, massive sand influx may be virtually eliminated, encouraging the uninterrupted development of the sand production mechanism in the reservoir. Plugging problems and pump failures may also be eliminated as the wells mature because sand, oil and water are allowed to drain into the cavern below, where sand settles, water separates and sandfree, clean oil is produced to surface.
Simulation work has demonstrated that the SuperSump System could improve CHOPS operations in the following ways: Recovery factors are 50% higher; Operating costs are 30% lower; Energy efficiency is better by 75%; and Greenhouse Gas Emissions are lower by 95%. Estimated costs indicate very favourable economics compared to conventional CHOPS operations.
The analysis of SuperSump System currently focuses on CHOPS operations in the Western Canadian Sedimentary Basin, but could be used anywhere CHOPS is applied. It appears to be especially effective for developing new small fields where the cost of surface facilities constitute a significant portion of the field development cost. SuperSump could also be beneficial in applications where high density drilling is required but there are sensitivities to surface footprint. SuperSump could also be a cost effective precursor to EOR/IOR.
To Start up Extra-heavy Oil or Bitumen Wells by Solvents after Drilling
Authors: Zhang Jie , Li Cuinan , Zeng Fanhua , Chen Ping , Zhang Zhen , Zhou Chenghua , Zhang Wenlong 
Published: June 2012

Abstract
Extra-heavy oil or bitumen wells are very difficult to start up and recover because of the high oil viscosity in cold production. It is necessary to get initial mobility by reducing the viscosity of oil or bitumen when the wells are drilled. Although there are mechanical ultrasonic stimulation technologies, the penetration of ultrasonic wave in the formation is very limited and their efficiency is not very good. Hot water or steam circulation is another option. However the heat loss in the wellbore is too significant to send enough heat to the targeted interval, specifically for deep reservoirs. Solvent could be a better option from both oil viscosity reduction and operation points of view. It can be injected into the well immediately after drilling for soaking, which is a convenient method to reduce viscosity without many complicated procedure as thermal methods. The concern for using solvent to reduce viscosity is selecting the optimal solvent. This paper studied the mixture of some typical extra-heavy oil and bitumen with solvent. After fully mixed with each other, viscosity reduction and potential precipitation have been investigated. Different solvents are discussed and recommended to reduce viscosity for new well start up and work-over.
A series of viscosity tests is conducted in the paper for heavy oil-solvent mixture under different temperatures to discuss the effect of three different solvents (diesel, ligarine and toluene) on viscosity reduction. Through these viscosity tests, the optimal solvent, temperature and solvent concentration for viscosity reduction are recommended. And it is found that after a solvent is placed in contact with heavy oil samples at any temperature in the range of 20 – 80C the reduction of viscosity can be significant. However, considering the economical effectiveness, diesel is not recommended. And 60–90 ligarine and toluene are better choices for starting up super heavy oil or bitumen wells. In addition, as to bitumen, due to its extremely high viscosity, using several times volume of solvent as the bitumen volume still can’t have the viscosity reduce to a desired value. So these solvents tested in the experiments are not recommended for bitumen well starting up after drilling.
Response to Early Generation Selection for Resistance to Rice Kernel Fissuring
Authors: Pinson Shannon R. M. , Jia Yulin , Gibbons James 
Published: June 2012

ABSTRACTThe value of milled rice (Oryza sativa L.) depends on the percent whole versus broken kernels after milling. Kernel fissures caused by pre‐ or postharvest stresses are the leading cause of breakage on milling. ‘Cypress’ is known to be more fissure resistant (FR) than most cultivars, but breeding success has been limited by a lack of ability to identify FR among F2 and F3 progeny. An induced‐fissuring method wherein small samples of seed are evaluated for fissure rates after controlled exposure to humid laboratory conditions can distinguish FR among pure‐breeding rice cultivars. To measure the efficacy of the induced‐fissuring system for evaluating FR among segregating breeding progeny, we applied divergent selection for FR and fissure susceptibility (FS) on seed harvested from ∼300 Cypress (FR) × ‘LaGrue’ (FS) F2 plants and evaluated selection success using seed from F2:3 plants grown in Arkansas and Texas. A second round of divergent selection was made among F3 progeny followed by F3:4 progeny testing. Fissure susceptible F2:3 progeny fissured twice as much as FR progeny, with an average response to selection of 13.5%. Response to F3 selection was smaller (averaging 2.6%), suggesting some fixation of alleles due to the F2 selections. Narrow‐sense heritabilities (h2) were 0.54 and 0.73 for the FR and FS F2 selections, respectively. This study documented successful early‐generation selection for FR, opening new opportunity for breeders to develop rice cultivars improved for this important trait.
Generation and Characterization of Interspecific Hybrids of Lotus uliginosus × Lotus corniculatus
Authors: Castillo A. , Rebuffo M. , Rizza M. Dalla , Folle G. , Santiñaque F. , Borsani O. , Monza J. 
Published: June 2012

ABSTRACTA method is described for obtaining interspecific hybrids between commercial lines of Lotus uliginosus Schkuhr and Lotus corniculatus L. Hybridization was possible between these species using embryo rescue. Two strategies were used to confirm 40 F1 hybrids, that is, flow cytometry and microsatellite simple sequence repeats (SSRs). The L. uliginosus and L. corniculatus parents have significantly different genome size (2.5 ± 0.02 and 2.22 ± 0.02 pg, respectively) and the offspring from the cross had intermediate values. Two SSR primers were polymorphic between the genotypes tested, TM1150 and EH380069. Maternal effect was detected in L. uliginosus genotypes, as determined by greater frequency of F1 hybrids. Recombinant traits were observed in the F1 hybrid progeny. Ninety F1 hybrids resulting from L. uliginosus × L. corniculatus crosses showed different levels of fertility in the polycross; <3% F1 plants produced more than 1000 seeds without embryo rescue while 10% of plants did not flower the first year. The F1 hybrid plants grown under greenhouse conditions exhibited shoot phenotypes similar to L. uliginosus (maternal) whereas F2 phenotypes were similar to L. corniculatus (paternal) in field trials. Rhizome presence was observed in 60% of F2 hybrid plants. The diameters of the root crowns of these plants, however, were similar to that of L. corniculatus.
An Assessment of Raffinose Family Oligosaccharides and Sucrose Concentration in Genus Lens
Authors: Tahir Mohammad , Båga Monica , Vandenberg Albert , Chibbar Ravindra N. 
Published: June 2012

ABSTRACTTo determine the natural variation for sucrose and raffinose family oligosaccharides (RFO) concentration in lentils (Lens culinaris Medik. ssp. culinaris), we analyzed a subset of 168 Lens germplasm lines from the ICARDA collection. Significant (P ≤ 0.05) variations were found for sucrose, total RFO concentrations, and composition of the three main RFO (specifically raffinose, stachyose, and verbascose). Sucrose concentration in domesticated genotypes ranged from 0.5 to 2.7 g 100 g−1 flour dry matter (DM) and was higher overall than the concentrations observed in wild genotypes (0.1 to 1.7 g 100 g−1 flour DM). Similarly, the RFO concentration in domesticated genotypes (4.0 to 6.1 mmoles 100 g−1 flour DM) was generally higher than in wild lentil genotypes (1.7 to 5.2 mmoles 100 g−1 flour DM). The verbascose, stachyose, and raffinose concentrations in domesticated genotypes ranged from 1.1 to 1.6 g, 1.5 to 3.5 g, and 1.5 to 3.0 g 100 g−1 flour DM, respectively, and were similar to concentrations measured in wild genotypes. Lens ervoides genotypes tended to have higher verbascose and lower stachyose concentrations than other genotypes. High raffinose and low verbascose concentrations were observed in Lens nigricans genotypes. The diversity in RFO, raffinose, and verbascose concentrations was higher in wild genotypes than domesticated lentils. Utilization of this natural variation in RFO concentration in genus Lens provides opportunities for the improvement of lentil seed quality.
Potential and Optimization of Genomic Selection for Fusarium Head Blight Resistance in Six‐Row Barley
Authors: Lorenz A. J. , Smith K.P. , Jannink J.‐L. 
Published: June 2012

ABSTRACTFusarium head blight (FHB),is a devastating disease of barley (Hordeum vulgare L.), causing reductions in yield and quality. Marker‐based selection for resistance to FHB and lowered deoxynivalenol (DON) grain concentration would save considerable costs and time associated with phenotyping. A marker‐based selection approach called genomic selection (GS) uses genomewide marker information to predict genetic value. We used a cross‐validation approach that separated training sets from validation sets by both entry and environment. We used this framework to test the potential of GS for genetic improvement of FHB and DON as well as test the effect of different factors on prediction accuracy. Prediction accuracy for FHB was found to be as high as 0.72 and that for DON was found to be as high as 0.68. Little difference was found between marker effect estimation methods in terms of prediction of entry genetic value. The extensive linkage disequilibrium (LD) present in this population allowed the marker set to be reduced to 384 markers and training population (TP) size to be reduced 200 with little effect on prediction accuracy. We found little to no advantage to combining subpopulations that correspond to neighboring breeding programs to increase TP size. Apparently, little genetic information is shared between subpopulations, either because of different marker–quantitative trait loci (QTL) linkage phases, different segregating QTL, or nonadditive gene action.
Genetic Yield Gains of the CIMMYT International Semi‐Arid Wheat Yield Trials from 1994 to 2010
Authors: Manès Y. , Gomez H. F. , Puhl L. , Reynolds M. , Braun H. J. , Trethowan R. 
Published: June 2012

ABSTRACTGenetic progress for yield has been assessed globally in the semi‐arid wheat yield trials (SAWYTs) of the International Maize and Wheat Improvement Center (CIMMYT) over a 17‐yr period. Grain yield expressed as a percentage of the long‐term check cultivar Dharwar Dry has increased at approximately 1% yr−1 between 1994 and 2010. In real terms, yield has been increased at a rate of 31 kg ha−1 yr−1. The rate of yield increase in high‐yielding environments was twice that of low‐yielding environments. The average yield of low‐yielding sites are significantly correlated with the average yield of high‐yielding sites (p < 0.001), and many of the highest‐yielding lines of the various SAWYT performed well at both low‐ and high‐yielding sites. The key parents Attila and Pastor were consistently high yielding in several of the early SAWYT. In later trials their derivatives were also high yielding. The line Vorobey, developed by crossing Pastor with a synthetic derivative, showed outstanding yield in SAWYT 11 and 12. The performance of CIMMYT lines compared to local check cultivars was relatively stable over time. A success rate was calculated as the ratio of the number of sites where a given line is superior to the local check divided by the total number of sites. On average, the success rate of the 10% best lines was 61% in low‐yielding sites and 62% in high‐yielding sites.
Persistence of Triticale Seed in the Soil Seed Bank
Authors: Raatz Lisa L. , Yang Rong‐Cai , Beres Brian L. , Hall Linda M. 
Published: June 2012

ABSTRACTSpring triticale (×Triticosecale Wittm. ex A. Camus) is being developed as a bio‐product crop for the Canadian prairies and may involve the use of genetic modification. Seed loss before or during harvest from genetically modified (GM) triticale could impact its ability to coexist with conventional crops. Experiments were conducted in Alberta, Canada, to determine if spring triticale exhibits primary dormancy relative to wheat (Triticum aestivum L.) and whether seeds persist in the seed bank. Primary dormancy was assessed for four triticale cultivars, AC Alta, Blue Aleurone, Tyndal, and AC Ultima, and AC Barrie wheat by quantifying germination weekly from anthesis to postharvest. Seed persistence was assessed for the same cultivars by placing seed‐filled mesh bags on the soil surface (0 cm) and at 2 and 12 cm burial depths. Before harvest in 2009, germinations were less than 56% for all cultivars. After harvest, AC Barrie and Blue Aleurone exhibited a short period of primary dormancy. In 2010, wet conditions were conducive to preharvest sprouting. Germinations ranged from 46 to 85% preharvest with no lingering primary dormancy postharvest. Seeds buried to 12 cm germinated readily, removing them from the seed bank within 7 mo, while 99% of seeds buried to 2 cm were nonviable 11 mo after burial. Seeds on the soil surface persisted longest; however, 99% were nonviable after 26 mo. Like wheat, triticale has little or no primary dormancy, and results from this study suggest triticale seed does not persist in the seed bank.