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Title: Impact of pore-water freshening on clays and the compressibility of hydrate-bearing reservoirs during production

Abstract

Gas production efficiency from natural hydrate-bearing sediments depends in part on geotechnical properties of fine-grained materials, which are ubiquitous even in sandy hydrate-bearing sediments. The responses of fine-grained material to pore fluid chemistry changes due to freshening during hydrate dissociation could alter critical sediment characteristics during gas production activities. We investigate the electrical sensitivity of fine grains to pore fluid freshening and the implications of freshening on sediment compression and recompression parameters.

Authors:
 [1];  [2];  [1];  [3]
  1. U.S. Geological Survey, Woods Hole, MA
  2. Louisiana State University, Baton Rouge, LA
  3. Chungbuk National University, Cheongju-si, Chungbuk, South Korea
Publication Date:
Research Org.:
Louisiana State University
Sponsoring Org.:
USDOE Office of Fossil Energy (FE)
OSTI Identifier:
1435694
Report Number(s):
DOE-LSU-FE0028966-1
DOE Contract Number:
FE0028966
Resource Type:
Conference
Resource Relation:
Journal Name: 9th ICGH 2017; Conference: 9th International Conference on Gas Hydrates (ICGH), June 25-30, 2017, Denver, Colorado USA
Country of Publication:
United States
Language:
English

Citation Formats

Jang, Junbong, Cao, Shuang, Waite, William, and Jung, Jongwon. Impact of pore-water freshening on clays and the compressibility of hydrate-bearing reservoirs during production. United States: N. p., 2017. Web.
Jang, Junbong, Cao, Shuang, Waite, William, & Jung, Jongwon. Impact of pore-water freshening on clays and the compressibility of hydrate-bearing reservoirs during production. United States.
Jang, Junbong, Cao, Shuang, Waite, William, and Jung, Jongwon. Sun . "Impact of pore-water freshening on clays and the compressibility of hydrate-bearing reservoirs during production". United States. doi:. https://www.osti.gov/servlets/purl/1435694.
@article{osti_1435694,
title = {Impact of pore-water freshening on clays and the compressibility of hydrate-bearing reservoirs during production},
author = {Jang, Junbong and Cao, Shuang and Waite, William and Jung, Jongwon},
abstractNote = {Gas production efficiency from natural hydrate-bearing sediments depends in part on geotechnical properties of fine-grained materials, which are ubiquitous even in sandy hydrate-bearing sediments. The responses of fine-grained material to pore fluid chemistry changes due to freshening during hydrate dissociation could alter critical sediment characteristics during gas production activities. We investigate the electrical sensitivity of fine grains to pore fluid freshening and the implications of freshening on sediment compression and recompression parameters.},
doi = {},
journal = {9th ICGH 2017},
number = ,
volume = ,
place = {United States},
year = {Sun Jun 25 00:00:00 EDT 2017},
month = {Sun Jun 25 00:00:00 EDT 2017}
}

Conference:
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  • The physical and chemical processes that affect reservoir fluids during production can be modeled by methodologies similar to those used for modeling clastic diagenesis. That these processes may result in formation damage and scale formation make them of interest to production geologists and engineers. Pathway modeling, based upon a series of critical divides, predicts which reactions are likely to occur between formation, production tubing, and reservoir fluids. Thermodynamic equilibria modeling calculates direction and magnitude of possible reactions. Integration of these approaches with observations of patterns of scale formation, production line, and formation damage yield a model capable of predicting themore » magnitude and direction of reactions that may produce negative impacts on reservoir production. Critical divides characterizing these processes in carbonate and sulfate mineral-bearing reservoirs include: (1) presence or absence of sulfate-bearing minerals within the production volume; (2) presence of iron within production line or formation; (3) ratio of concentration of bicarbonate to hydrogen sulfide; (4) capacity of aqueous and solid phases to buffer formation fluid pH; and (5) magnitude of pressure and temperature drops during production. The model qualitatively predicts: (1) likelihood of sulfide, sulfate, or carbonate mineral precipitation during production; (2) souring of the reservoir; and (3) corrosion of production tubing. The model has been developed from production histories for Weber Sandstone reservoirs, Colorado and Wyoming, and has been applied to examples of reservoir production from Tensleep and Minnelusa reservoirs in Wyoming.« less
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