Effects of pore structure on surfactant/polymer flooding-based enhanced oil recovery in conglomerate reservoirs

To understand the displacement characteristics and remaining oil displacement process by the surfactant/polymer (SP) flooding in cores with different pore structures, the effects of pore structure on the enhanced oil recovery of SP flooding was investigated at the pore, core and field scales through...

Full description

Bibliographic Details
Main Authors: Zheyu LIU, Yiqiang LI, Runxi LENG, Zhenping LIU, Xin CHEN, Hossein HEJAZI
Format: Article
Language:English
Published: KeAi Communications Co., Ltd. 2020-02-01
Series:Petroleum Exploration and Development
Online Access:http://www.sciencedirect.com/science/article/pii/S187638042060012X
_version_ 1818413074139316224
author Zheyu LIU
Yiqiang LI
Runxi LENG
Zhenping LIU
Xin CHEN
Hossein HEJAZI
author_facet Zheyu LIU
Yiqiang LI
Runxi LENG
Zhenping LIU
Xin CHEN
Hossein HEJAZI
author_sort Zheyu LIU
collection DOAJ
description To understand the displacement characteristics and remaining oil displacement process by the surfactant/polymer (SP) flooding in cores with different pore structures, the effects of pore structure on the enhanced oil recovery of SP flooding was investigated at the pore, core and field scales through conducting experiments on natural core samples with three typical types of pore structures. First, the in-situ nuclear magnetic resonance core flooding test was carried out to capture the remaining oil variation features in the water flooding and SP flooding through these three types of cores. Subsequently, at the core scale, displacement characteristics and performances of water flooding and SP flooding in these three types of cores were evaluated based on the full-size core flooding tests. Finally, at the field scale, production characteristics of SP flooding in the bimodal sandstone reservoir and multimodal conglomerate reservoir were compared using the actual field production data. The results show: as the pore structure gets more and more complex, the water flooding performance gets poorer, but the incremental recovery factor by SP flooding gets higher; the SP flooding can enhance the producing degree of oil in 1–3 μm pores in the unimodal and bimodal core samples, while it produces largely oil in medium and large pores more than 3 μm in pore radius in the multimodal core sample. The core flooding test using full-size core sample demonstrates that the injection of SP solution can significantly raise up the displacement pressure of the multimodal core sample, and greatly enhance recovery factor by emulsifying the remaining oil and enlarging swept volume. Compared with the sandstone reservoir, the multimodal conglomerate reservoir is more prone to channeling. With proper profile control treatments to efficiently enlarge the microscopic and macroscopic swept volumes, SP flooding in the conglomerate reservoir can contribute to lower water cuts and longer effective durations. Key words: conglomerate reservoir, pore structure, surfactant/polymer flooding, displacement effect, oil recovery enhancement
first_indexed 2024-12-14T10:57:25Z
format Article
id doaj.art-d75472747df94f69a5b4bf0500f42c40
institution Directory Open Access Journal
issn 1876-3804
language English
last_indexed 2024-12-14T10:57:25Z
publishDate 2020-02-01
publisher KeAi Communications Co., Ltd.
record_format Article
series Petroleum Exploration and Development
spelling doaj.art-d75472747df94f69a5b4bf0500f42c402022-12-21T23:04:53ZengKeAi Communications Co., Ltd.Petroleum Exploration and Development1876-38042020-02-01471134145Effects of pore structure on surfactant/polymer flooding-based enhanced oil recovery in conglomerate reservoirsZheyu LIU0Yiqiang LI1Runxi LENG2Zhenping LIU3Xin CHEN4Hossein HEJAZI5State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China; Department of Chemical and Petroleum Engineering, University of Calgary, Calgary T2N 1N4, CanadaState Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China; Corresponding authorResearch Institute of Exploration and Development, PetroChina Xinjiang Oilfield Company, Karamay 834000, ChinaResearch Institute of Exploration and Development, PetroChina Xinjiang Oilfield Company, Karamay 834000, ChinaState Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, ChinaDepartment of Chemical and Petroleum Engineering, University of Calgary, Calgary T2N 1N4, CanadaTo understand the displacement characteristics and remaining oil displacement process by the surfactant/polymer (SP) flooding in cores with different pore structures, the effects of pore structure on the enhanced oil recovery of SP flooding was investigated at the pore, core and field scales through conducting experiments on natural core samples with three typical types of pore structures. First, the in-situ nuclear magnetic resonance core flooding test was carried out to capture the remaining oil variation features in the water flooding and SP flooding through these three types of cores. Subsequently, at the core scale, displacement characteristics and performances of water flooding and SP flooding in these three types of cores were evaluated based on the full-size core flooding tests. Finally, at the field scale, production characteristics of SP flooding in the bimodal sandstone reservoir and multimodal conglomerate reservoir were compared using the actual field production data. The results show: as the pore structure gets more and more complex, the water flooding performance gets poorer, but the incremental recovery factor by SP flooding gets higher; the SP flooding can enhance the producing degree of oil in 1–3 μm pores in the unimodal and bimodal core samples, while it produces largely oil in medium and large pores more than 3 μm in pore radius in the multimodal core sample. The core flooding test using full-size core sample demonstrates that the injection of SP solution can significantly raise up the displacement pressure of the multimodal core sample, and greatly enhance recovery factor by emulsifying the remaining oil and enlarging swept volume. Compared with the sandstone reservoir, the multimodal conglomerate reservoir is more prone to channeling. With proper profile control treatments to efficiently enlarge the microscopic and macroscopic swept volumes, SP flooding in the conglomerate reservoir can contribute to lower water cuts and longer effective durations. Key words: conglomerate reservoir, pore structure, surfactant/polymer flooding, displacement effect, oil recovery enhancementhttp://www.sciencedirect.com/science/article/pii/S187638042060012X
spellingShingle Zheyu LIU
Yiqiang LI
Runxi LENG
Zhenping LIU
Xin CHEN
Hossein HEJAZI
Effects of pore structure on surfactant/polymer flooding-based enhanced oil recovery in conglomerate reservoirs
Petroleum Exploration and Development
title Effects of pore structure on surfactant/polymer flooding-based enhanced oil recovery in conglomerate reservoirs
title_full Effects of pore structure on surfactant/polymer flooding-based enhanced oil recovery in conglomerate reservoirs
title_fullStr Effects of pore structure on surfactant/polymer flooding-based enhanced oil recovery in conglomerate reservoirs
title_full_unstemmed Effects of pore structure on surfactant/polymer flooding-based enhanced oil recovery in conglomerate reservoirs
title_short Effects of pore structure on surfactant/polymer flooding-based enhanced oil recovery in conglomerate reservoirs
title_sort effects of pore structure on surfactant polymer flooding based enhanced oil recovery in conglomerate reservoirs
url http://www.sciencedirect.com/science/article/pii/S187638042060012X
work_keys_str_mv AT zheyuliu effectsofporestructureonsurfactantpolymerfloodingbasedenhancedoilrecoveryinconglomeratereservoirs
AT yiqiangli effectsofporestructureonsurfactantpolymerfloodingbasedenhancedoilrecoveryinconglomeratereservoirs
AT runxileng effectsofporestructureonsurfactantpolymerfloodingbasedenhancedoilrecoveryinconglomeratereservoirs
AT zhenpingliu effectsofporestructureonsurfactantpolymerfloodingbasedenhancedoilrecoveryinconglomeratereservoirs
AT xinchen effectsofporestructureonsurfactantpolymerfloodingbasedenhancedoilrecoveryinconglomeratereservoirs
AT hosseinhejazi effectsofporestructureonsurfactantpolymerfloodingbasedenhancedoilrecoveryinconglomeratereservoirs