Method for Initializing Grain Mass and Persisting Dry Condition of a Core Sample

Sang Kyu Lee; Tae Jong Lee; Youngmin Lee

doi:10.12972/ksmer.2015.52.6.559

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2015 Vol.52, Issue 6 Preview Page Next Page

Research Paper

Method for Initializing Grain Mass and Persisting Dry Condition of a Core Sample 시험편의 고체질량 초기화와 건조 지속 방법

31 December 2015. pp. 559-566

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Abstract

A method for initializing grain mass and maintaining dry condition of a core sample has been suggested. It is validated by effective porosity and resistivity measurements of cement core samples. Injection of noble gas such as nitrogen gas during the drying process of a core sample can ignore the environmental factors of the core beforehand and initialize the grain mass and sustain the core in dry condition for a while by keeping the pore space from infiltrating the humidity in the air. Injection of nitrogen gas into the dried cement cores effectively block or delay the humidity invasion into the pore space, so that one can get grain mass with minimum humidity in its pore space, and can perform an long term resistivity monitoring of the dry sample. Based on the suggested method and experiment results, it is suggested to modify the standard test method for effective porosity and density of rocks.

Keywords

Effective porosity

Initializing the grain mass

Dry process

Noble gas

Cement sample

코어의 유효공극률 측정에 있어서 그 정확성과 반복성을 높일 수 있도록 고체질량을 초기화하고 이 건조상태를 지속시키는 방법을 제안하고 그 효과를 유효공극률과 전기비저항 측정을 통해 살펴보았다. 암석코어 시험편이 겪은 환경 이력에 관계없이 내부를 완전하게 건조시켜서 고체질량을 초기화하고 필요에 따라서 이 건조 상태를 지속시키는 방법으로 건조 공정 중에 질소가스(불활성가스)를 주입하는 기술을 고안하였다. 원주형 시멘트 시험편에 대해 고안된 기술을 적용한 결과, 질소가스를 주입하면 공기에 포함된 수분이 시험편 내부로 흡수되는 것을 효과적으로 차단 또는 지연시킬 수 있어서 시험편의 내부 수분을 최소화한 고체질량을 얻을 수 있고 건조한 암석코어의 전기비저항을 장시간 모니터링할 수 있었다. 이를 토대로 유효공극률을 측정하는 표준시험법의 수정을 제안하였다.

키워드

유효공극률

고체질량 초기화

건조 공정

불활성 가스

시멘트 시험편

References

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Information

Publisher :The Korean Society of Mineral and Energy Resources Engineers
Publisher(Ko) :한국자원공학회
Journal Title :Journal of the Korean Society of Mineral and Energy Resources Engineers
Journal Title(Ko) :한국자원공학회지
Volume : 52
No :6
Pages :559-566
Received Date : 2015-10-26
Revised Date : 2015-11-26
Accepted Date : 2015-12-17
DOI :https://doi.org/10.12972/ksmer.2015.52.6.559

Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

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