556 IEEE SENSORS JOURNAL, VOL. 13, NO. 2, FEBRUARY 2013

Online Monitoring of Geological CO2 Storage andLeakage Based on Wireless Sensor Networks

Hui Yang, Yong Qin, Gefei Feng, and Hui Ci

Abstract A remote online carbon dioxide (CO2) concentra-tion monitoring system is developed, based on the technologiesof wireless sensor networks, in allusion to the gas leakage mon-itoring requirement for CO2 capture and storage. The remoteonline CO2 monitoring system consists of monitoring equipment,a data center server, and the clients. The monitoring equipmentis composed of a central processing unit (CPU), air environmentsensors array, global positioning system (GPS) receiver module,secure digital memory card (SD) storage module, liquid crystaldisplay (LCD) module, and general packet radio service (GPRS)wireless transmission module. The sensors array of CO2, temper-ature, humidity, and light intensity are used to collect data andthe GPS receiver module is adopted to collect location and timeinformation. The CPU automatically stores the collected datain the SD card data storage module and displays them on theLCD display module in real-time. Afterwards, the GPRS modulecontinuously wirelessly transmits the collected information tothe data center server. The online monitoring WebGIS clientsare developed using a PHP programming language, which runson the Apache web server. MySQL is utilized as the databasebecause of its speed and reliability, and the stunning cross-browser web maps are created, optimized, and deployed withthe OpenLayers JavaScript web-mapping library. Finally, anexperiment executed in Xuzhou city, Jiangsu province, China isintroduced to demonstrate the implementation and application.

Index Terms CO2 capture and storage (CSS), general packetradio service (GPRS), global positioning system (GPS), remoteonline leakage monitoring, wireless sensor networks (WSN).

I. INTRODUCTION

ATMOSPHERIC concentrations of the key greenhouse gas(GHG) carbon dioxide (CO2) well above pre-industriallevels constitute the main cause for the predicted rise ataverage surface temperature on Earth and the correspondingchange of the global climate system [1]. CO2 Capture and

Manuscript received June 16, 2012; revised August 31, 2012; acceptedSeptember 19, 2012. Date of publication October 9, 2012; date of currentversion January 11, 2013. This work was supported in part by the ChinaPostdoctoral Science Foundation Grant 2012M510193, the National NaturalScience Foundation of China Grant 41001230, the Important National Scienceand Technology Specific Projects Grant 2011ZX05034, and the PriorityAcademic Program Development of Jiangsu Higher Education Institutions.The associate editor coordinating the review of this paper and approving itfor publication was Prof. Gotan H. Jain.

H. Yang, Y. Qin, and H. Ci are with the School of Resource and EarthScience and the Key Laboratory of CBM Resource and Reservoir FormationCourse, Ministry of Education, China University of Mining and Technology,Xuzhou 221116, China (e-mail: whinee@gmail.com; yongqin@cumt.edu.cn;ci_hui@163.com).

G. Feng is with the Jiangsu College Key Lab of Linguistic Sciences andNeuro-Cognition Engineering and the Linguistic Science College, JiangsuNormal University, Xuzhou 221116, China (e-mail: fspeed@jsnu.edu.cn).

Color versions of one or more of the figures in this paper are availableonline at http://ieeexplore.ieee.org.

Digital Object Identifier 10.1109/JSEN.2012.2223210

Storage (CCS) is on the one hand an effective way to realizeeffective greenhouse gas storage, and on the other to improveoil and gas production [2]. Many countries such as the UnitedStates, Japan, and Canada are in search of effective approachesfor CO2 storage in either geological formations or ocean. InChina, the first demonstrative industrial project of CO2 storagehas come into operation in Shenhua mine area.

However, once CO2 leaks from the storage reservoir, all theefforts human beings have made to fight global warming wouldbe go down the drain. Therefore, what is in needed after thegeological CO2 storage is long-term terrain monitoring of thegreenhouse gas leakage, which is absolutely crucial to helpensure that geologic sequestration of CO2 is safe. For thisreason, the development of remote online monitoring systemis of great significance to geological CO2 storage and leakagewarning.

Recent advances in information and communication tech-nologies have resulted in the development of more efficient,low cost and multi-functional sensors. These micro-sensorscan be deployed in wireless sensor networks (WSN) tomonitor and collect air environmental information such asCO2 concentration, temperature, humidity, light intensity, airpressure, wind power, wind direction, etc. The informationis then wirelessly transmitted to data center server wherethey are integrated and analyzed for evaluating of geologicalCO2 storage and leakage. Deploying sensor networks allowsinaccessible areas to be covered by minimizing the sensingcosts compared with the use of separate sensors to completelycover the same area [3].

The remainder of this paper is as follows. Section 2 presentsthe backgrounds of CCS leakage monitoring based on WSNand their related issues. Section 3 describes the hardwareinfrastructure of CO2 leakage monitoring equipment and dif-ferent sensors and modules selected. Section 4 demonstratesthe firmware flow of CO2 remote online monitoring system.In section 5, the implementation and application example ispresented. Finally, section 6 is the conclusion of the paper andnew avenues for the future works are put forward in this part.

II. BACKGROUNDSA. Monitoring of CCS Leakage

The effective application of monitoring technologies shouldensure the safety of CCS projects, with respect to both humanhealth and the environment, and will contribute greatly tothe development of relevant technical approaches for mon-itoring and verification [4]. Many tools exist or are beingdeveloped for monitoring geological CO2 storage, including

1530437X/$31.00 2012 IEEE