检索结果-南通市图书馆

A Data-Oriented Method to Optimize Hydraulic Fracturing Parameters of Tight Sandstone Reservoirs

在线全文

学校读者我要写书评

暂无评论

Energy Engineering 2024年第6期121卷 1657-1669页

作者： Zhengrong Chen Mao Jiang Chuanzhi Ai Jianshu Wu Xin Xie CNOOC Research Institute Co. Ltd.Beijing100028China

Based on the actual data collected from the tight sandstone development zone, correlation analysis using theSpearman method was conducted to determine the main factors influencing the gas production rate of tightsandstone fracturing. An integrated model combining geological engineering and numerical simulation of fracturepropagation and production was completed. Based on data analysis, the hydraulic fracture parameters wereoptimized to develop a differentiated fracturing treatment adjustment plan. The results indicate that the influenceof geological and engineering factors in the X1 and X2 development zones in the study area differs significantly.Therefore, it is challenging to adopt a uniform development strategy to achieve rapid production increase. Thedata analysis reveals that the variation in gas production rate is primarily affected by the reservoir thickness andpermeability parameters as geological factors. On the other hand, the amount of treatment fluid and proppantaddition significantly impact the gas production rate as engineering factors. Among these factors, the influence ofgeological factors is more pronounced in block X1. Therefore, the main focus should be on further optimizing thefracturing interval and adjusting the geological development well location. Given the existing well location, thereis limited potential for further optimizing fracture parameters to increase production. For block X2, the fracturingparameters should be optimized. Data screening was conducted to identify outliers in the entire dataset, and adata-driven fracturing parameter optimization method was employed to determine the basic adjustment directionfor reservoir stimulation in the target block. This approach provides insights into the influence of geological,stimulation, and completion parameters on gas production rate. Consequently, the subsequent fracturing parameteroptimization design can significantly reduce the modeling and simulation workload and guide field operations toimprove and optimize hydraulic fracturing effic

关键词： Data mechanism driven fracturing parameters gas production correlation tight sandstone gas

Numerical studies of hydrate dissociation and gas production behavior in porous media during depressurization process

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Natural gas Chemistry 2012年第4期21卷 381-392页

作者： Xuke Ruan Mingjun Yang Yongchen Song Haifeng Liang Yanghui Li Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of TechnologyDalian 116023LiaoningChina College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina

In this study, a numerical model is developed to investigate the hydrate dissociation and gas production in porous media by depressurization. A series of simulation runs are conducted to study the impacts of permeability characteristics, including permeability reduction exponent, absolute permeability, hydrate accumulation habits and hydrate saturation, sand average grain size and irreducible water saturation. The effects of the distribution of hydrate in porous media are examined by adapting conceptual models of hydrate accumulation habits into simulations to govern the evolution of permeability with hydrate decomposition, which is also compared with the conventional reservoir permeability model, i.e. Corey model. The simulations show that the hydrate dissociation rate increases with the decrease of permeability reduction exponent, hydrate saturation and the sand average grain size. Compared with the conceptual models of hydrate accumulation habits, our simulations indicate that Corey model overpredicts the gas production and the performance of hydrate coating models is superior to that of hydrate filling models in gas production, which behavior does follow by the order of capillary coating〉pore coating〉pore filling〉capillary filling. From the analysis of tl/2, some interesting results are suggested as follows：（1） there is a ＂switch＂ value （the ＂switch＂ absolute permeability） for laboratory-scale hydrate dissociation in porous media, the absolute permeability has almost no influence on the gas production behavior when the permeability exceeds the ＂switch＂ value. In this study, the ＂switch＂ value of absolute permeability can be estimated to be between 10 and 50 md. （2） An optimum value of initial effective water saturation Sw,e exists where hydrate dissociation rate reaches the maximum and the optimum value largely coincides with the value of irreducible water saturation Swr,e. For the case of Sw,e〈,Swr,e, or Sw,e〉Swr,e, there are different control mechanisms dominating the process of hydrate dissociation and ga

关键词： gas hydrate numerical simulation permeability dissociation gas production depressurization

In vitro Ruminal gas production Kinetics of Four Fodder Trees Ensiled With or Without Molasses and Urea

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2013年第7期12卷 1234-1242页

作者： Abdelfattah Z M Salem ZHOU Chuan-she TAN Zhi-liang Miguel Mellado Moises Cipriano Salazar Mona M M Y Elghandopur Nicholas E Odongo Faculty of Veterinary and Livestock Autonomous University of the State of Mexico Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Department of Animal Nutrition Autonomous Agrarian University Antonio Narro Faculty of Veterinary and Livestock Autonomous University of Guerrero

This study investigated if the addition of urea （U）, molasses （M） or their 1：1 （v/v） mixture during ensiling increases the nutritional value of forage from four fodder trees （Prunus persica, Leucaena esculenta, Acacia farnesiana, and Prunus domestica）. Forage samples of fodder trees were collected in triplicate （three individual samples of each species） and subjected to an in vitro gas production （GP） procedure. Fermentation at 24 h （GP 24）, short-chain volatile fatty acids （SCFA）, and microbial crude protein production （MCP）, in vitro organic matter digestibility （OMD）, metabolizable energy （ME） and dry matter degradability （DMD） were estimated. Forage samples were incubated for 72 h in an incubator at 39oC and the volume of GP was recorded at 2, 4, 6, 8, 10, 12, 24, 48, and 72 h of incubation using the reading pressure technique. The rumen fermentation profiles were highest for P. persica, which showed the highest （P〈0.0001） DMD, ME, OMD, SCFA, GP 24 and MCP. On the other hand L. esculenta had the lowest （P〈0.0001） DMD, SCFA, MCP; P. domestica had the lowest （P〈0.0001） OMD. The addition of M to silage increased （P〈0.0001） ME and OMD, as well as GP. However, the addition of U and the mixture of U and M reduced （P〈0.0001） DMD, ME, OMD, SCFA, GY 24 and MCP. These results show that P. persica has the highest nutritive value and L. esculenta the lowest for ruminants. Additionally, the addition of M to forage from fodder trees increases rumen GP and fermentation, which may improve nutrient utilization in ruminants.

关键词： fodder trees urea molasses gas production

Effects of cellulase and xylanase enzymes mixed with increasing doses of Salix babylonica extract on in vitro rumen gas production kinetics of a mixture of corn silage with concentrate

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2015年第1期14卷 131-139页

作者： Abdelfattah Z M Salem German Buendía-Rodríguez Mona M M Elghandour María A Mariezcurrena Berasain Francisco J Pea Jiménez Alberto B Pliego Juan C V Chagoyán María A Cerrillo Miguel A Rodríguez Faculty of Veterinary Medicine and Animal Science Autonomous University of the State of Mexico National Center of Disciplinary Research in Animal Physiology and Improvement INIFAP Ajuchitlán Institute of Agricultural Sciences Autonomous University of HidalgoEx-Hda. of Aquetzalpa Faculty of Veterinary Medicine and Animal Science Juárez University of the Durango State

An in vitro gas production （GP） technique was used to investigate the effects of combining different doses of Salix babylonica extract （SB） with exogenous fibrolytic enzymes （EZ） based on xylanase （X） and cellulase （C）, or their mixture （XC; 1：1 v/v） on in vitro fermentation characteristics of a total mixed ration of corn silage and concentrate mixture （50：50, w/w） as substrate. Four levels of SB （0, 0.6, 1.2 and 1.8 mL g-1 dry matter （DM）） and four supplemental styles of EZ （1 μL g-1 DM; control （no enzymes）, X, C and XC （1：1, v/v） were used in a 4×4 factorial arrangement. In vitro GP （mL g-1 DM） were recorded at 2, 4, 6, 8, 10, 12, 24, 36, 48 and 72 h of incubation. After 72 h, the incubation process was stopped and supernatant pH was determined, and then filtered to determine dry matter degradability （DMD）. Fermentation parameters, such as the 24 h gas yield （GY24）, in vitro organic matter digestibility （OMD）, metabolizable energy （ME）, short chain fatty acid concentrations （SCFA）, and microbial crude protein production （MCP） were also estimated. Results indicated that there was a SBxEZ interaction （P〈0.0001） for the asymptotic gas production （b）, the rate of gas production （c）, GP from 6 to 72 h, GP2 （P=0.0095）, and GP4 （P=0.02）. The SB and different combination of enzymes supplementation influenced （P〈0.001） in vitro GP parameters after 12 h of incubation; the highest doses of SB （i.e., 1.8 mL g-1 DM）, in the absence of any EZ, quadratically increased （P〈0.05） the initial delay before GP begins （L） and GP at different incubation times, with lowering b （quadratic effect, P〈0.0001 ） and c （quadratic effect, P〈0.0001 ; linear effect, P=0.0018）. The GP was the lowest （P〈0.05） when the highest SB level was combined with cellulose. There were SBxEZ interactions （P〈0.001） for OMD, ME, the partitioning factor at 72 h of incubation （PF72）, GY24, SCFA, MCP （P=0.0143）, and pH （P=0.0008）. The OMD, ME, GY24 and SCFA with supplementation of SB extract at 1.8 mL g-1 DM were higher （P〈0.001） than the other treatments, howev

关键词： cellulase degradability gas production Salix babylonica xylanase

Experimental Study on the Influence of Fracturing Fluid Retention on Shale gas Diffusion Law

在线全文

学校读者我要写书评

暂无评论

Energy Engineering 2023年第8期120卷 1853-1866页

作者： Zhiyuan Yao Jing Sun Dehua Liu Cooperative Innovation Center of Unconventional Oil and gas(Ministry of Education&Hubei Province) Yangtze UniversityWuhanChina Petroleum Engineering College Yangtze UniversityWuhanChina Hubei Shale gas Development Engineering Technology Research Center Yangtze UniversityWuhanChina

Shale gas reservoirs have poor physical properties and a large number of micro-nano pores have been developed.Shale gas wells have no natural productivity and need fracturing reconstruction measures to put into production.However,the fracturing fluid will enter the reservoir space of shale matrix after fracturing and affect the production of shale gas.At present,there is no consensus on the influence of fracturing fluid retention on gas well production.Based on this,the paper adopts gas molecular transport analyzer to carry out experimental research on the influence of fracturing fluid on shale gas diffusion law after entering matrix pores.The results show that:(1)Compared with the diffusion capacity of single-phase shale gas,the diffusion capacity of shale gas decreases significantly when fracturing fluid is present in the reservoir;(2)In the process of fracturing fluid flowback,when the water saturation in the reservoir decreases from 50%to 0,the gas well productivity increases by about 60%.(3)When fracturing fluid exists in the reservoir,the pore diameter has an exponential relationship with the shale gas diffusion coefficient,and the diffusion coefficient increases exponentially with the increase of pore diameter.The research of this paper provides theoretical basis for guiding the efficient development of shale gas wells.

关键词： Shale gas micro nano pore water saturation diffusion law gas production

Chemical composition and in vitro fermentation characteristics of high sugar forage sorghum as an alternative to forage maize for silage making in Tarim Basin, China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2016年第1期15卷 175-182页

作者： ZHANG Su-jiang Abdul Shakoor Chaudhry Diky Ramdani Amerjan Osman GUO Xue-feng Grant Raymond Edwards Long Cheng Key Laboratory of Tarim Animal Husbandry Science and Technology College of Animal Science Tarim University School of Agriculture Food and Rural Development Newcastle University Faculty of Animal Husbandry University Padjadjaran College of Plant Science and Technology Tarim University Faculty of Agriculture & Life Sciences Lincoln University

The chemical composition, mineral profile and in vitro fermentation characteristics of maize （MZ）, high sugar forage sorghum （HS） and forage sorghum （FS）, and silages made from each forage type were measured. The MZ and MZ silage （MZS） had higher crude protein, starch and ether extract contents than both sorghum forages and sorghum silages. HS had higher ash and water-soluble carbohydrate concentrations than FS and MZ. MZ, MZS, HS and HS silage （HSS） had lower neutral detergent fibre, acid detergent fibre and acid detergent lignin than FS and FS silage （FSS）. FSS had higher dry matter （DM） and pH than MZS and HSS. HSS contained higher concentrations of P and K than FSS and MZS. MZS and HSS had higher in vitro dry matter and organic matter digestibility, CH4 production, total volatile fatty acids, acetate and propionate than FSS. pH was higher for FSS than for HSS, and ammonia was lower for HSS than for MZS and FSS. HSS had higher gas production than MZS and FSS after 2, 4, 6 and 8 h incubation. MZS had higher gas production than HSS and FSS after 26 and 28 h of incubation. The results indicate that HS may substitute for MZ to make good quality silage. However, animal studies are needed to assess the acceptability and feeding values of HSS vs. MZS for ruminant production.

关键词： high sugar forage sorghum maize silage digestibility methane gas production

Low temperature microwave-assisted vs conventional pyrolysis of various biomass feedstocks

在线全文

学校读者我要写书评

暂无评论

Journal of Natural gas Chemistry 2012年第3期21卷 270-274页

作者： Peter Shuttleworth Vitaliy Budarin Mark Gronnow James H.Clark Rafael Luque Green Chemistry Centre of Excellence University of YorkHeslingtonYO10 5DD YorkUK Departamento de Química Orgnica Universidad de CórdobaCampus de Excelencia Agroalimentario ceiA3Edif icio Marie Curie(C-3)Ctra Nnal IVKm 396E-14014CórdobaSpain

A comparison between conventional pyrolysis and a novel developed low-temperature microwave-assisted pyrolysis methodology has been performed for the valorisation of a range of biomass feedstocks including waste residues. Microwave pyrolysis was found to efficiently deliver comparable evolution of bio-gases in the system as compared with conventional pyrolysis at significantly reduced temperatures （120-180 ℃vs 250-400 ℃）. The gas obtained from microwave-assisted pyrolysis was found to contain CO2, CH4 and CO as major components as well

关键词： microwave-assisted pyrolysis biomass valorisation gas production

Monitoring the fibrolytic potential of microbial ecosystems from domestic and wild ruminants browsing tanniferous forages

在线全文

学校读者我要写书评

暂无评论

Animal Nutrition 2016年第1期2卷 40-44页

作者： Nokwethemba Nqobile Philile Msimango Fabian Nde Fon Department of Agriculture Faulty of Science and Agriculture University of Zululand

Although the rumen microbiome has been reported to synthesize a rich source of symbiotic enzymes(exocellulase, endocellulase, hemicellulase and cellobiase), the digestion of tropical C_4 grasses and browses by ruminants is still limited. Therefore, this study aimed to unveil potential fibrolytic microbial ecosystems from giraffe, kudu, impala and consortia(A1 [giraffe + kudu], A2 [giraffe + impala], A3[kudu + impala], and A4 [giraffe + kudu + impala]) browsing tanniferous plants, which can be used to improve forage utilization in domesticated goat. Crude protein enzyme extracts(CPZ) from fresh faecal samples were precipitated by 60% ammonium sulphate and assayed for exocellulase, endocellulase and hemicellulase by incubating with crystalline cellulose, carboxymethyl cellulose and xylan at 38 ℃ with optimum pH of 5.5 to 6.5 for 1, 2, and 48 h, respectively. Enzyme specific activities were defined as μg of reducing sugar/mg CPZ. In vitro fermentation study was done by transferring 33 mL of fresh faecal inoculum into 67 mL of salivary buffer containing 1 g Acacia sieberiana and incubating for 72 h at 38 ℃,Apparent degradability(APDeg), true degradability(TD), neutral detergent fibre degradability(NDFdeg),acid detergent fibre degradability(ADFdeg), microbial yield(MY), metabolizable energy(ME) and total gas emitted(gas) were measured. Exocellulase activities were higher(P gas than the goat system. This study showed that microbial ecosystems from wild browsers(especial

关键词： Cellulase Hemicellulase Fermentation Tanniferous forage gas production

Effects of Encapsulated Enzyme and Yeast Products on in Vitro Rumen Fermentation

在线全文

学校读者我要写书评

暂无评论

Journal of Northeast Agricultural University(English Edition) 2022年第2期29卷 28-37页

作者： Zhang Mei-mei Liang Ge-ge Chen Ming-ming Jin Long Xie Xiao-lai Zhang Yong-gen Jiao Pei-xin College of Animal Sciences and Technology Northeast Agricultural UniversityHarbin 150030China Agriculture and Agri-Food Canada Lethbridge Research and Development CentreLethbridge T1J 4B1Canada

Batch cultures of mixed rumen micro-organisms were conducted to evaluate the effects of encapsulated yeast(+EY)and encapsulated enzyme(+EE)using plant proteins(barley and oats grain)on rumen fermentation in vitro,investigate the abilities of encapsulated yeast and encapsulated enzyme to prevent rumen digestion in vitro.Treatments of the study were the control,+EY,+EE products(3.33 mg·mL^(-1) of the incubation medium),unencapsulated yeast(-EY)and enzyme(-EE)products(0.17 and 0.17μL·mL^(-1) of the incubation medium,respectively).+EY group increased dry matter disappearance(DMD,Pgas production(GP)of+EY group was higher(P=0.05,29.94 mL·mL^(-1) organic matter,OM)than that of the control(25.08 mL·g^(-1) OM)at 3 h of the incubation.Supplementation+EY increased DMD(P=0.04,0.394 vs 0.352,respectively)and acetic proportion(P=0.04,52.6 vs 49.8 mol•100 mL^(-1),respectively)at 6 h of the incubation and increased A:P ratio(P<0.01,3.11 and 2.86,respectively)at 24 h of the incubation,as compared to unencapsulation of yeast.Supplementation of enzyme had higher(P≤0.04)GP,DMD and TVFA at 3 and 6 h of the incubation compared with the control,regardless of encapsulation.Moreover,the addition of+EE produced greater GP at 6(P<0.01,92.35 vs 78.21 mL·g^(-1) OM,respectively),12(218.47 vs 159.18 mL·g^(-1) OM)and 24 h(380.97 vs 297.78 mL·g^(-1) OM,respectively)of the incubation,higher DMD(0.347 vs 0.313,respectively)at 3 h of the incubation as compared to-EE group.The study showed that the encapsulation might protect part of yeast and enzyme from releasing to the rumen throughout the digestion in vitro,resulting in higher or no difference of rumen fermentation parameters compared with unencapsulated groups at any incubation times.In comparison with-EY and-EE,the higher rumen fermentation parameters at the early incubation time were observed,which could be attributed to the higher concentration of yeast

关键词： dry matter digestion encapsulated enzyme encapsulated yeast gas production in vitro volatile fatty acid