Maximizing the Utilization of Emitted Co2 from Gas Field by Implementing Co2 Source and Sink Clustering

Abstract

Managing CO2 emission in oil and gas industries have always been a heavy task to be performed. It is worth noting that the amount of CO2 released into the atmosphere has always been a function of oil and gas production itself. Therefore, it is not possible to reduce CO2 by means of reducing oil and gas production. One of the biggest challenges in reducing CO2 emission in Indonesia’s oil and gas industries is the constantly growing need of fossil fuel as well as the lack of carbon tax on Indonesia’s law. Carbon tax, in which a tax is imposed carbon generating activities, has been successfully applied in several countries, but not in Indonesia. Currently Indonesian government is developing presidential decree of carbon pricing in order to accelerate the fulfilment of Indonesian NDC (Nationally Determined Contribution) and on the same time the carbon credit excess could be offered to International communities. New discoveries of oil and gas fields in same areas in Indonesia, especially in Java and Sumatra Islands, have now shifted into CO2 rich fields, where the CO2 will become a major obstacle in developing the fields economically. One of the issues in developing CO2 rich fields is how to dispose the CO2 safely or even adding some added value into the disposed CO2. This paper offers an alternative of disposing CO2 from CO2 rich gas fields by injecting it into oil and gas reservoir by means of CO2-EOR or CO2-EGR. Despite its urgency, CO2-EOR and CO2-EGR has not been implemented on a full field scale in Indonesia, but some studies have been conducted, e.g. in Gundih and Tangguh fields. In order to increase the understanding that CO2-EOR or CO2-EGR implementation in Indonesia will be economic beneficial projects, we propose to build a cluster-based approach of CO2 management all around Indonesia. Bades on the developed system, it is hoped that one can see that the costs of CO2 transportation will be minimum, because the distance between several CO2 sources and potential CO2 sinks are close one to the others. Besides that, one can predict easily that there will be potentially additional recovery from the injected CO2 to the oil and gas fields through the implementation of CO2-EOR or CO2-EGR. The case study in East Java region is shown in this paper. This study presents an effort to classify CO2 source and sink that could be connected to future CO2-EOR and CO2-EGR activities in a near future. Oil and gas exploitation activities in this area yields substantial production with high CO2 content, therefore efforts should be taken to utilize the CO2, not only as flared gas that has the potential to pollute its surrounding areas. It is then decided that the CO2 will be utilized as EOR/EGR media to nearby fields, however, care should be taken in order to ensure the economic and technical aspect of CO2 injection itself. Three clusters are defined, i.e. 30 km, 60 km and 90 km in order to distinguish between prioritized fields and less prioritized fields. Prior to field selection and calculation, screening processes are performed based on available criteria in order to find the most suitable target fields based on reservoir properties and the remaining oil in place. As conclusion, this paper addresses an effort to map potential of CO2-EOR and CO2-EGR nearby East Java oil and gas fields as well as power plant in Indonesia, where the potential application of CO2-EOR in Indonesia would reach 400 BSCF of CO2 sequestered and possibility of 56 MMBO additional oil extracted. It is hoped that this study could be used as a reference on how to develop cost efficient CO2-EOR and CO2-EGR in Indonesia.