ArticlePublisher preview available

Environmental security control of resource utilization of shale gas’ drilling cuttings containing heavy metals

September 2017
Environmental Science and Pollution Research 24(31)

Authors:

The overall objective of this research project was to investigate the heavy metals environmental security control of resource utilization of shale gas’ drilling cuttings. To achieve this objective, we got through theoretical calculation and testing, ultimately and preliminarily determine the content of heavy metals pollutants, and compared with related standards at domestically and abroad. The results indicated that using the second Fike’s law, the theoretical model of the release amount of heavy metal can be made, and the groundwater environmental risk as main point compared with soil. This study can play a role of standard guidance on environmental security control of drilling cuttings resource utilization by the exploration and development of shale gas in our country.

Pre-processes of drilling cuttings

…

Treatment processes of water-based drillings

…

Treatment processes of oil-based drillings

…

Solidify process flow diagram

…

Solidify pool runoff liquid monitoring site

…

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RESEARCH ARTICLE

Environmental security control of resource utilization of shale

gas’drilling cuttings containing heavy metals

Chao-qiang Wang

1,2,3,4

&Xiao-yan Lin

1,3

&Chun Zhang

2,4

&Xu-dong Mei

2,4

Received: 16 March 2017 /Accepted: 4 July 2017 /Published online: 7 August 2017

#Springer-Verlag GmbH Germany 2017

Abstract The overall objective of this research project was to

investigate the heavy metals environmental security control of

resource utilization of shale gas’drilling cuttings. To achieve

this objective, we got through theoretical calculation and test-

ing, ultimately and preliminarily determine the content of

heavy metals pollutants, and compared with related standards

at domestically and abroad. The results indicated that using

the second Fike’s law, the theoretical model of the release

amount of heavy metal can be made, and the groundwater

environmental risk as main point compared with soil. This

study can play a role of standard guidance on environmental

security control of drilling cuttings resource utilization by the

exploration and development of shale gas in our country.

Keywords Environmental security .Shale gas .Drilling

cuttings .Resource utilization

Introduction

With the rapid development of China’seconomy,energyde-

mand is constantly increasing, and shale gas, as the new type

energy resources, has become one of the major motivations in

the economic development of China. In the course of explo-

ration and development of shale gas, we use water-based dril-

ling fluid in straight hole, and then water-based drillings cir-

culate the ground which includes water-based cuttings and a

portion of water-based mud. In addition, we use oil-based

drilling fluid of multi-interval fracturing technology in hori-

zontal well for gas recovery, and then oil-based drillings cir-

culate the ground which include oil-based cuttings and a por-

tion of oil-based mud. The pre-processes of water/oil-based

drilling fluid and cuttings are presented in Fig.1. All the pro-

cesses are mainly through the vibrating screen system, which

available the water/oil-based drilling cuttings. In one well

about 1000 m

water-based cuttings would be generated,

and about 250 m

oil-based cuttings would be generated.

Because they are a kind of solid waste which contains organic

pollutant, pressure filtration technique is used to ensure the

safe discharge. The water-based drillings’water content of

the produced will be controlled within 13% which can guar-

antee solidification treatment. The oil-based residues’oil con-

tent of the produced will be controlled within 0.3% through

pyrolysis procedures which can guarantee solidification treat-

ment (Leonard and Stegemann 2010).

Treatment processes of water-based drillings

Water-based drilling is a kind of solid waste which contains

organic pollutant, so it must be pre-processed to ensure safe

disposal. Figure 2is the treatment process drawing and com-

prehensive utilization of WDC. It is clear that the pressure

filtration technique is used to ensure the safe discharge of

Responsible editor: Philippe Garrigues

*Xiao-yan Lin

linxiaoyan@swust.edu.cn

Institute of School of Materials Science and Engineering, Southwest

University of Science and Technology, Sichuan Province,

Mianyang 621010, China

Chongqing Environmental Protection Center for Shale Gas

Technology & Development, Fuling, Chongqing 400800, China

Technology and Engineering Research Center of Biomass Materials,

Ministry of Education, Southwest University of Science and

Technology, Sichuan Province, Mianyang 621010, China

Chongqing Environmental Protection Engineering Technology

Center for Shale Gas Development, Fuling, Chongqing 408000,

China

Environ Sci Pollut Res (2017) 24:21973–21983

DOI 10.1007/s11356-017-9703-0

Content courtesy of Springer Nature, terms of use apply. Rights reserved.

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Article

May 2011

This study determined the concentration of three heavy metals zinc (Zn), lead (Pb), and cadmium (Cd) in soil and in a woody plant species, Milicia excelsa, at Ishiagu quarry, Nigeria. The highest soil concentrations of Zn, Pb, and Cd in soil were obtained at 1 m from the quarry site. In M. excelsa, the highest concentrations of Zn, Pb, and Cd were 3.12–9.1, 3.9–6.01, and 0.51–1.12 mg kg−1, respectively. There were significant positive correlations between Cd and Zn (r = 0.963) and Cd and Pb (r = 0.974) in plants as well as between Cd and Pb (r = 9.84) in soil. The level of Cd in soil reflected significant pollution compared to average global concentrations in soils.