Impact of well location on total production rate

Acetic, propionic, and butyric acids labelled with 14C were infused into the caecum of continuously fed sheep. The specific activity of the volatile fatty acids (VFA) in the caecum was determined at intervals during the infusion. The production rate was calculated by isotope dilution from the results of those experiments in which steady state conditions were obtained. Substantial interconversions occurred between the fatty acid fractions. The total production of VFA was about 440 mmoles/day, equivalent to 125 kcal/day or 5.3% of the animal's digestible energy intake.

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Decline Curve Analysis of Fractured Horizontal Wells Through Segmented Fracture Model

Journal of Energy Resources Technology ◽

10.1115/1.4040533 ◽

2018 ◽

Vol 141 (1) ◽

Cited By ~ 12

Author(s):

Jiazheng Qin ◽

Shiqing Cheng ◽

Youwei He ◽

Yang Wang ◽

Dong Feng ◽

...

Keyword(s):

Production Rate ◽

History Matching ◽

Curve Analysis ◽

Production Performance ◽

Fracture Model ◽

Total Production ◽

Type Curves ◽

Decline Curve Analysis ◽

Decline Curve ◽

Compound Type

Nowadays, production performance evaluation of a multifractured horizontal well (MFHW) has attracted great attention. This paper presents a mathematical model of an MFHW with considering segmented fracture (SF) for better evaluation of fracture and reservoir properties. Each SF consists of two parts: fracture segment far from wellbore (FSFW) and fracture segment near to wellbore (FSNW) in segmented fracture model (SFM), which is different from fractures consists of only one segment in common fracture model (CFM). Employing the source function and Green's function, Newman's product method, Duhamel principle, Stehfest inversion algorithm, and Laplace transform, production solution of an MFHW can be obtained using SFM. Total production rate is mostly contributed from FSNW rather than FSFW in many cases; ignoring this phenomenon may lead to obvious erroneous in parameter interpretation. Thus, clear distinctions can be found between CFM and SFM on the compound type curves. By using decline curve analysis (DCA), the influences of sensitive parameters (e.g., dimensionless half-length, dimensionless production rate, conductivity, and distance between SF) on compound type curves are analyzed. The results of sensitivity analysis are benefit of parameter estimation during history matching.

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Condition-Based Production Planning: Adjusting Production Rates to Balance Output and Failure Risk

Manufacturing & Service Operations Management ◽

10.1287/msom.2019.0773 ◽

2020 ◽

Vol 22 (4) ◽

pp. 792-811 ◽

Cited By ~ 4

Author(s):

Michiel A. J. uit het Broek ◽

Ruud H. Teunter ◽

Bram de Jonge ◽

Jasper Veldman ◽

Nicky D. Van Foreest

Keyword(s):

Production Rate ◽

Production Systems ◽

Real Life ◽

Problem Definition ◽

Total Production ◽

Production Rates ◽

Rate Condition ◽

Deterioration Rate ◽

Failure Risk ◽

Production Output

Problem Definition: Many production systems deteriorate over time as a result of load and stress caused by production. The deterioration rate of these systems typically depends on the production rate, implying that the equipment’s deterioration rate can be controlled by adjusting the production rate. We introduce the use of condition monitoring to dynamically adjust the production rate to minimize maintenance costs and maximize production revenues. We study a single-unit system for which the next maintenance action is scheduled upfront. Academic/Practical Relevance: Condition-based maintenance decisions are frequently seen in the literature. However, in many real-life systems, maintenance planning has limited flexibility and cannot be done last minute. As an alternative, we are the first to propose using condition information to optimize the production rate, which is a more flexible short-term decision. Methodology: We derive structural optimality results from the analysis of deterministic deterioration processes. A Markov decision process formulation of the problem is used to obtain numerical results for stochastic deterioration processes. Results: The structure of the optimal policy strongly depends on the (convex or concave) relation between the production rate and the corresponding deterioration rate. Condition-based production rate decisions result in significant cost savings (by up to 50%), achieved by better balancing the failure risk and production output. For several systems a win-win scenario is observed, with both reduced failure risk and increased expected total production. Furthermore, condition-based production rates increase robustness and lead to more stable profits and production output. Managerial Implications: Using condition information to dynamically adjust production rates provides opportunities to improve the operational performance of systems with production-dependent deterioration.

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CATECHOLAMINES AND (INTERMEDIATE) CORTICOID METABOLISM IN NORMAL MALES AND FEMALES

Acta Endocrinologica ◽

10.1530/acta.0.0380262 ◽

1961 ◽

Vol 38 (2) ◽

pp. 262-275 ◽

Cited By ~ 3

Author(s):

P. De Moor ◽

E. Meulepas ◽

M. Hinnekens ◽

W. Grevendonck ◽

A. Hendrikx

Keyword(s):

Production Rate ◽

Removal Rate ◽

Marked Change ◽

Distribution Volume ◽

Total Production ◽

Acth Stimulation ◽

Males And Females ◽

Normal Males ◽

Male Subjects ◽

Concentration Curves

ABSTRACT Epinephrine (25 ng/kg/min I.V.), administered to normal males causes a marked change in the plasma corticoid concentration curves obtained during maximal stimulation with corticotrophin (ACTH). This finding is not observed in females. The altered pattern described in the male subjects is due to a significant increase of the removal rate without a concomittant change in the production rate, resulting in a decrease of the plateau and the C8 corticoid concentration. An augmented cortisol storage outside the readily miscible distribution volume could be responsible for this increased removal rate. The administration of norepinephrine (120 ng/kg/min I. V.) causes an increase in the production rate during ACTH stimulation in normal males and females. As indicated by the unchanged level of urinary cortisol metabolites, there is no change in the total production of adrenal corticoids; thus a decrease of the mean distribution volume of the readily miscible corticoids is probable. An increase of the removal rate is also observed under these circumstances in males but not in females. As to the diurnal variation of plasma corticoids during ACTH stimulation, significant quantitative and qualitative differences are found between the sexes during the evening and night. Some of these differences in males disappear after the administration of phentolamine methanesulfonate (Regitine), which suggests an interference of endogenous catecholamines in the observed phenomenon.

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Oil Production Optimization in Petroleum Reservoirs by Ant Algorithm

Chemical Product and Process Modeling ◽

10.2202/1934-2659.1166 ◽

2008 ◽

Vol 3 (1) ◽

Author(s):

Fatemeh Razavi ◽

Farhang Jalali-Farahani

Keyword(s):

Ant Colony Optimization ◽

Production Rate ◽

Petroleum Reservoirs ◽

Injection Rate ◽

Ant Colony ◽

Ant Colony Optimization Algorithm ◽

Hydrocarbon Production ◽

Well Location ◽

Decision Variables ◽

Flow Pressure

The objective of the research presented in this paper is to investigate the effectiveness of a new stochastic algorithm to obtain maximum hydrocarbon production rate in petroleum reservoirs. The hydrocarbon production rate is a function of several variables. Some of these variables are production well location, production well flow pressure, injection well location and fluid injection rate. Changing any of the variables will change the hydrocarbon production rate value. By using stochastic optimization techniques, there is no limit to the number of decision variables that can be optimized simultaneously. The presented method in this paper is a new metaheuristic algorithm which enables us to analyze a system of mathematical equations containing a large number of decision variables and determine the optimum values of them that should give the most economic result. This is referred to as the Ant Colony Optimization Algorithm. Ant Colony Optimization technique leads us to lower computational cost to optimize complicated problems too. Although applied to discrete domains, this algorithm with some modifications has been applied to continuous optimization. Here, a numerical simulation is initially applied for modeling the hydrocarbon reservoir and then the results are analyzed and furthermore optimized to enhance profitability using Ant Colony Optimization algorithm. The developed code in MATLAB environment, based on Ant Colony Optimization, is able to estimate production and injection wells location, fluid injection rate and well flow pressure which would result in improved hydrocarbon production. This algorithm is simple to implement and the results of case studies show its ability to provide fast and accurate solutions. Results prove the reliability of algorithm for solving a large class of optimization problems in petroleum engineering.

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Production optimization of a network of multiple wells with each well using a combination of Electrical Submersible Pump and Gas lift

Journal of Petroleum Exploration and Production Technology ◽

10.1007/s13202-021-01313-z ◽

2021 ◽

Author(s):

Son Tung Pham ◽

Dinh Hau Tran

Keyword(s):

Energy Saving ◽

Production Rate ◽

Small Diameter ◽

Production Optimization ◽

Optimization Process ◽

Binary Search Tree ◽

Optimum Operating ◽

Total Production ◽

Artificial Lift ◽

Gas Lift

AbstractArtificial lift methods such as ESP and GL are commonly used in oil wells around the world, especially in offshore wells. However, these two methods are normally used separately, and this paper therefore aimed to study the possible combination of ESP and GL by analyzing its effects on energy saving using equivalent depth method and on production rate as well as on ESP life cycle using nodal analysis. The paper also performed the production optimization for a network of wells using each well a combination of GL and ESP. The optimization process consists of selecting the appropriate operation frequency for the ESP system and the injection gas lift distributed to each well with the aim of maximizing the total production of the network. In addition, this optimization process was conducted in two cases: unlimited and limited volume of injection gas lift. In case the GL flow is limited, the BST (Binary Search Tree) algorithm was used to determine the suitable gas rates injected into each well to maximize the total network production. The optimization workflow proposed in this study was applied to the field X in Cuu Long basin of Vietnam and was calibrated from the real data of this field. The results demonstrated the advantage of the combination of ESP and GL in energy saving and in application for small diameter wells. In addition, the workflow and source code will allow engineers to replicate the results and to apply this method for future studies in order to determine optimum operating parameters of this hybrid artificial lift to achieve the highest production rate from a network of multiple wells.

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Rates of production of methane in the rumen and large intestine of sheep

British Journal Of Nutrition ◽

10.1079/bjn19760053 ◽

1976 ◽

Vol 36 (1) ◽

pp. 1-14 ◽

Cited By ~ 133

Author(s):

R. M. Murray ◽

A. M. Bryant ◽

R. A. Leng

Keyword(s):

Production Rate ◽

Digestive Tract ◽

Large Intestine ◽

Methane Production ◽

Total Production ◽

Tracer Method ◽

Isotope Tracer ◽

Methane Production Rate ◽

Lower Digestive Tract ◽

Isotope Tracer Method

1. An isotope tracer method for estimating methane production in sheep is described.2. The technique was used to estimate methane produced in both the upper and lower digestive tract and to determine the routes by which it was excreted.3. Four Merino ewes given lucerne chaff (33 g every hour) were used.4. Total methane production rate was 21±1.1 (se) ml/min; production in the rumen accounted for 87±1.2% of the total production; 95±1.4% of the methane produced in the rumen was excreted by eructation.5. Of the methane produced in the lower digestive tract, 89±2.3% was excreted through the lungs and 11% through the anus.

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Observational study on the breeding performance of emus (Dromaius novaehollandiae) in Brazil

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/1678-4162-12028 ◽

2020 ◽

Vol 72 (6) ◽

pp. 2157-2164

Author(s):

J.C.P. Quintero ◽

L.F.L. Calixto ◽

A.J. Almeida ◽

Y.R. Moreira ◽

S.S. Rocha ◽

...

Keyword(s):

Observational Study ◽

Production Rate ◽

Breeding Season ◽

Egg Production ◽

Total Production ◽

Breeding Performance ◽

Production Potential ◽

Dromaius Novaehollandiae ◽

Different Ages

ABSTRACT The objective of this study was to describe emus’ breeding performance in Brazil at different ages, grouped in couples or colonies. The duration of the breeding season and the production of eggs per female housed were recorded, and the productivity and breeding variables were associated with the variation of the photoperiod. The total production of the flock was 180 eggs, and the breeding season lasted 167 days (April-September), a period with an average of 11 h and 11min of daylight. The breeding season lasted 113, 133 and 82 days, the numbers of eggs produced per female were 7.29, 25.67 and 17.3, and productivity values were 31.6, 38.6, and 45.4% in the groups of birds with ages of two, four and seven years, respectively. The breeding season in 2016 occurred between April and August in Brazil. Older birds tended to start breeding later. The production rate observations indicated that earlier peak production was associated with lower egg production potential. Finally, there was a tendency for better breeding performance of birds housed in couples than in groups with more birds.

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Comparative aspects of volatile fatty acid production in the rumen and distal fermentation chamber in Svalbard reindeer

Rangifer ◽

10.7557/2.17.2.1355 ◽

1997 ◽

Vol 17 (2) ◽

pp. 81 ◽

Cited By ~ 8

Author(s):

W. Sørmo ◽

Ø.E. Haga ◽

R.G. White ◽

S.D. Mathiesen

Keyword(s):

Fatty Acid ◽

Production Rate ◽

Volatile Fatty Acid ◽

Proximal Part ◽

Total Production ◽

Fatty Acid Production ◽

Svalbard Reindeer ◽

Volatile Fatty Acid Concentration ◽

Plant Fibre ◽

Different Seasons

Microbial fermentation end products were investigated in Svalbard reindeer at two different locations, on Nordenskioldland (NL) (n=7) and in a marginal area on Nordaustlandet (NA) (n=11), at different seasons. The pH ranged from 6.51-6.70 in rumen contents and from 6.78-7.17 in the distal fermentation chamber (DFC=caecum and proximal part of the colon) on NL compared to 6.10-6.71 in rumen contents and 6.50-7.35 in DFC contents on NA. The ruminal volatile fatty acid concentration ([VFAJ) was 84.5 ± 9.5 mmol/l compared to 63-9 ± 17.6 mmol/kg in the DFC on NL in winter. In autumn, ruminal and DFC [VFA] was high at 113.5 ± 13.0 mmol/l and 90.4 ± 10.9 mmol/kg, respectively. On NA ruminal [VFA] was 85.7 ± 12.4 mmol/l and 59-6 ± 1.3 mmol/kg in the DFC in winter, compared to 107.3 ± 18.4 mmol/l and 102.0 ± 12.7 mmol/kg in rumen and DFC, respectively, in summer. Mean acetate/propionate (A/P) ratios in the rumen indicate fermentation in favour of plant fibre digestion in winter (4.8) but not in autumn (3.0) on NL. On NA, the mean A/P ratio was 5.1 in winter, compared to 4.6 in summer. In all DFC investigated the A/P ratio was higher than 8.9. The initial ruminal [VFA] did not reflect the VFA production measured. On NL, the production rate of VFA was low or not detectable in rumen and DFC in winter, while in autumn the total production rate of VFA was 59.3 kJ/kgW0 75/d, of which 6.5% originated from the DFC. On NA in winter, a total of 121.3 kJ/kgW0 7S/d was estimated of which 17% originated from the DFC, compared to a total of 380.4 kj/kgW0.75/d in summer where the DFC only contributed 2.7%. Plants (grasses and mosses) with low quality in winter do not seem to contribute significantly to the VFA production in rumen and DFC. VFA production in the DFC seems to be of significant importance in reindeer when pastures have low availability but high quality. The concenttation and the rate of VFA production in the DFC contents were not related to the size of the chamber, but to the diet eaten.

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A Model for a Multistage Fractured Horizontal Well with Rectangular SRV in a Shale Gas Reservoir

Geofluids ◽

10.1155/2020/8845250 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18

Author(s):

Jianfa Wu ◽

Jian Zhang ◽

Cheng Chang ◽

Weiyang Xie ◽

Tianpeng Wu

Keyword(s):

Mathematical Model ◽

Production Rate ◽

Shale Gas ◽

Horizontal Well ◽

Horizontal Wells ◽

Total Production ◽

Gas Reservoirs ◽

Shale Gas Reservoirs ◽

Reservoir Permeability ◽

Fractured Horizontal Well

Although great success has been achieved in the shale gas industry, accurate production dynamic analyses is still a challenging task. Long horizontal wells coupling with mass hydraulic fracturing has become a necessary technique to extract shale gas efficiently. In this paper, a comprehensive mathematical model of a multiple fractured horizontal well (MFHW) in a rectangular drainage area with a rectangular stimulated reservoir volume (SRV) has been established, based on the conceptual model of “tri-pores” in shale gas reservoirs. Dimensionless treatment and Laplace transformation were employed in the modeling process, while the boundary element method was used to solve the mathematical model. The Stehfest numerical inversion method and computer programing techniques were employed to obtain dimensionless type curves, production rate, and cumulative production. Results suggest that 9 flow stages can be observed from the pseudopressure derivative type curve when the reservoir and the SRV are large enough. The number of fractures, SRV permeability, and reservoir permeability have no effect on the total production when the well is abandoned. As SRV and reservoir permeability increases, the production rate is much higher in the middle production stage. Although the SRV scale and its permeability are very important for early and intermediate production rates, the key factors restricting the shale gas production rate are the properties of the shale itself, such as adsorbed gas content, natural fractures, and organic content. The proposed model is useful for analyzing production dynamics with stimulated horizontal wells in shale gas reservoirs.

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