scholarly journals A study of the mechanism of nonuniform production rate in shale gas based on nonradioactive gas tracer technology

2020 ◽  
Vol 8 (7) ◽  
pp. 2648-2658
Author(s):  
Shan Huang ◽  
Wuguang Li ◽  
Jianfa Wu ◽  
Haijie Zhang ◽  
Yuanping Luo
Keyword(s):  
Production Rate ◽  
Shale Gas ◽  
Gas Tracer

Reservoir Study for Shale Gas Horizontal Casing Completion Multi-Stage Frac Using Gas Tracer Technology

2017 ◽  
Author(s):  
Yun Miao ◽  
Bo Zeng ◽  
Changlin Zhou ◽  
Yaoguang Wu ◽  
Yongbin Shan
Keyword(s):  
Shale Gas ◽  
Multi Stage ◽  
Gas Tracer

scholarly journals Production Rate Analysis of Fractured Horizontal Well considering Multitransport Mechanisms in Shale Gas Reservoir

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-17 ◽  
Author(s):  
Qi-guo Liu ◽  
Wei-hong Wang ◽  
Hua Liu ◽  
Guangdong Zhang ◽  
Long-xin Li ◽  
...  
Keyword(s):  
Production Rate ◽  
Shale Gas ◽  
Horizontal Well ◽  
Production Performance ◽  
Natural Fractures ◽  
Gas Reservoir ◽  
Isothermal Adsorption ◽  
Well Production ◽  
Shale Gas Reservoir ◽  
Fractured Horizontal Well

Shale gas reservoir has been aggressively exploited around the world, which has complex pore structure with multiple transport mechanisms according to the reservoir characteristics. In this paper, a new comprehensive mathematical model is established to analyze the production performance of multiple fractured horizontal well (MFHW) in box-shaped shale gas reservoir considering multiscaled flow mechanisms (ad/desorption and Fick diffusion). In the model, the adsorbed gas is assumed not directly diffused into the natural macrofractures but into the macropores of matrix first and then flows into the natural fractures. The ad/desorption phenomenon of shale gas on the matrix particles is described by a combination of the Langmuir’s isothermal adsorption equation, continuity equation, gas state equation, and the motion equation in matrix system. On the basis of the Green’s function theory, the point source solution is derived under the assumption that gas flow from macropores into natural fractures follows transient interporosity and absorbed gas diffused into macropores from nanopores follows unsteady-state diffusion. The production rate expression of a MFHW producing at constant bottomhole pressure is obtained by using Duhamel’s principle. Moreover, the curves of well production rate and cumulative production vs. time are plotted by Stehfest numerical inversion algorithm and also the effects of influential factors on well production performance are analyzed. The results derived in this paper have significance to the guidance of shale gas reservoir development.

scholarly journals A dual-tube model for gas dynamics in fractured nanoporous shale formations

2014 ◽  
Vol 757 ◽  
pp. 943-971 ◽  
Author(s):  
I. Lunati ◽  
S. H. Lee
Keyword(s):  
Production Rate ◽  
Shale Gas ◽  
Structural Parameters ◽  
Knudsen Diffusion ◽  
Effective Diffusion ◽  
Reliable Estimate ◽  
Hydraulic Fractures ◽  
Late Time ◽  
Transport Mechanisms ◽  
Shale Formations

AbstractGas flow through fractured nanoporous shale formations is complicated by a hierarchy of structural features (ranging from nanopores to microseismic and hydraulic fractures) and by several transport mechanisms that differ from the standard viscous flow used in reservoir modelling. In small pores, self-diffusion becomes more important than advection; also, slippage effects and Knudsen diffusion might become relevant at low densities. We derive a nonlinear effective diffusion coefficient that describes the main transport mechanisms in shale-gas production. In dimensionless form, this coefficient depends only on a geometric factor (or dimensionless permeability) and on the kinetic model that describes the gas. To simplify the description of the complex structure of fractured shales, we observe that the production rate is controlled by the flow from the shale matrix (which has the smallest diffusivity) into the fracture network, which is assumed to produce instantaneously. Therefore, we propose to model the flow in the shale matrix and estimate the production rate with a simple bundle-of-dual-tubes model (BoDTM), in which each tube is characterized by two diameters (one for transport and the other for storage). The solution of a single tube is approximately self-similar at early time, but not at late time, when the gas flux decays exponentially owing to the finite length of the tube. To construct a BoDTM, a reliable estimate of the joint statistics of the matrix-porosity parameters is required. This can be either inferred from core measurements or postulated on the basis of somea prioriassumptions when information from laboratory and field measurements is scarce. By comparison with field production data from the Barnett shale-gas field, we demonstrate that BoDTM can be calibrated to estimate structural parameters of the shale formation and to predict the cumulative production of shale gas. Our framework has enough flexibility to construct models of increasing complexity that can be employed in the presence of a complex dataset or when more information is available.

scholarly journals Numerical prediction of the decline of the shale gas production rate with considering the geomechanical effects based on the two-part Hooke’s model

Fuel ◽  
2016 ◽  
Vol 185 ◽  
pp. 362-369 ◽  
Author(s):  
Jiangtao Zheng ◽  
Yang Ju ◽  
Hui-Hai Liu ◽  
Liange Zheng ◽  
Moran Wang
Keyword(s):  
Production Rate ◽  
Shale Gas ◽  
Gas Production ◽  
Numerical Prediction

scholarly journals Production Behavior of Fractured Horizontal Well in Closed Rectangular Shale Gas Reservoirs

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Qiguo Liu ◽  
Ke Li ◽  
Weihong Wang ◽  
Xiaohu Hu ◽  
Hua Liu
Keyword(s):  
Production Rate ◽  
Shale Gas ◽  
Superposition Principle ◽  
Stable State ◽  
Hydraulic Fractures ◽  
Gas Reservoirs ◽  
Desorption Process ◽  
Shale Gas Reservoirs ◽  
Wellbore Pressure ◽  
Production Behavior

This paper established a triple porosity physical model in rectangular closed reservoirs to understand the complex fluid flowing mechanism and production behavior of multifractured horizontal wells in shale gas reservoirs, which is more appropriate for practical situation compared with previous ones. According to the seepage theory considering adsorption and desorption process in stable state, the gas production rate of a well producing at constant wellbore pressure was obtained by utilizing the methods of Green’s and source function theory and superposition principle. Meanwhile, the volume of adsorbed gas (GL) and the number of hydraulic fractures (M) as well as permeabilities of matrix system (km) and microfractures (kf) were discussed in this paper as sensitive factors, which have significant influences on the production behavior of the wells. The bigger the value ofGLis, the larger the well production rate will be in the later flowing periods, and the differences of production rate with the increasing ofMare small, which manifest that there is an optimumMfor a given field. Therefore, the study in this paper is of significant importance to understand the dynamic production declining performance in shale gas reservoirs.

A New Analytical Method for Analyzing Linear Flow in Tight/Shale Gas Reservoirs: Constant-Rate Boundary Condition

2012 ◽  
Vol 15 (01) ◽  
pp. 51-59 ◽  
Author(s):  
Morteza Nobakht ◽  
C.R.. R. Clarkson
Keyword(s):  
Production Rate ◽  
Shale Gas ◽  
Analytical Method ◽  
Gas Production ◽  
Square Root ◽  
Gas Reservoirs ◽  
Linear Flow ◽  
Shale Gas Reservoirs ◽  
Straight Line ◽  
Time Plot

Summary Hydraulically fractured vertical and horizontal wells completed in shale gas and some tight gas plays are known to exhibit long periods of linear flow. Recently, techniques for analyzing this flow period using (normalized) production data have been put forth, but there are known errors associated with the analysis. In this paper, linear flow from fractured wells completed in tight/shale gas reservoirs subject to a constant-production-rate constraint is studied. We show analytically that the square-root-of-time plot (a plot of rate-normalized pressure vs. square root of time that is commonly used to interpret linear flow) depends on the production rate. We also show that depending on production rate, the square-root-of-time plot may not be a straight line during linear flow; the higher the production rate, the earlier in time the plot deviates from the expected straight line. This deviation creates error in the analysis, especially for flow-regime identification. To address this issue, a new analytical method is developed for analyzing linear-flow data for the constant-gas-rate production constraint. The method is then validated using a number of numerically simulated cases. As expected, on the basis of the analytical derivation, the square-root-of-time plots for these cases depend on gas-production rate and, for some cases, the plot does not appear as a straight line during linear flow. Finally, we found that there is excellent agreement between the fracture half-lengths obtained using this method and the input fracture half-lengths entered in to numerical simulation.

Sign in / Sign up

Export Citation Format

Share Document