The UAE may have become the leading sour gas-producing country in the region, by virtue of the huge hydrogen sulphide-rich gas reserves in the fields of Abu Dhabi, but the country could not have achieved this feat without implementing some tried-and-tested exploration and production (E&P) technology – German expertise, for instance.
Wintershall, an E&P company and subsidiary of German chemicals giant BASF, has been involved with the Abu Dhabi National Oil Company (ADNOC) since 2012, as part of an agreement to conduct feasibility studies and chemical enhanced oil recovery (cEOR) experiments to produce sour gas from one of the rich yet complex gas fields in the Abu Dhabi desert, Shuwaihat. Since entering into the partnership, Wintershall has spudded one well, studied numerous reservoir samples, and plans to drill a second well offshore – a first for Abu Dhabi – all to determine the feasibility of a production project, as Mario Mehren, Wintershall’s CEO, told Oil & Gas Middle East at DIPEC 2015.
“We are working in about 10 sour gas field projects in Germany. We also have chemical drilling expertise from our parent company BASF. ADNOC has been picking their partners quite carefully and has put their trust in us,” he explained.
In April, Martin Bachmann, the company’s head of exploration and production for Europe and the Middle East, said: “I am looking for a 35 to 40-year relationship [with ADNOC].” And Wintershall has an ace up its sleeve. Having spent years working on some of Germany’s most challenging fields, it might be the only drilling company in the region that knows how to unlock Shuwaihat’s difficult reserves.
“One of the reasons we brought the field of EOR to ADNOC and to Abu Dhabi is because we’d been working on EOR for a long time. We have all the research capability, all the labs, everything that BASF does, at our disposal,” Bachman said.
The Shuwaihat field is known for its high concentration of sulphur (about 20% of H2S content) and challenging geology that means EOR will be required to develop its reserves. As an expert in the field of EOR and improved oil recovery (IOR), Wintershall is well positioned to provide ADNOC with the technical know-how on EOR, while its access to special chemicals through its parent company BASF might prove crucial in developing a tailor-made product that tackles the geological challenges in question.
“We looked at the whole portfolio of BASF and we are looking at which chemicals will be right for the special conditions there,” Bachmann said.
“One of the challenges that we have in the Middle East – and I think this is why nobody is doing [EOR] on a big scale yet – is that the reservoir rocks are mainly carbonates, not sand; often there is [a high content of] sulphur in the reservoir, and the temperature is quite high. These three things make it quite challenging to find the right chemicals.”
“The second challenge is — and we know this from [our experience in] Germany — how you apply it in the field. What sounds simple — I take the chemical, inject it in the reservoir and produce oil — is much more complex in practice. But, once we have selected a pilot, that would be the next step.”
Wintershall is hoping to secure a 35 to 40-year contract to develop the field, with Bachmann saying a production agreement could be struck as early as next year. “The contract that we have allows us to go into developing and operating the field. Whether it is going to be done in a big development in the region, we will have to see. I think we’ve made a good first step in demonstrating that we can drill complicated oil and gas wells. I think the next step is to come up with a field development plan and create a concept for developing the field.”
With regards to the update on the status of the Shuwaihat sour gas project, Uwe Salge, general manager Middle East, Wintershall, further told Oil & Gas Middle East during ADIPEC last year: “At this stage we are happy with the results. Next year we will start with the second appraisal well, which we expect to complete by 2017, which is when we will go for Shuwaihat 6 and then, later on, Shuwaihat 7. We will have little analysis phases in between. As we know that producing sour gas has its complexities, we need to complete a sequence of wells to fully understand what volumes are behind this. That would determine the development concept, which we will plan in 2017.”
It is widely known that producing sour gas, especially in the GCC, is an expensive affair and involves the use of chemical methods. Regarding the developmental costs of the Shuwaihat project, Mehren said, “Producing sour gas is challenging and has to be done in a manner that is profitable to both companies (ADNOC and Wintershall). It is too early to talk about costs. We just have the find from the first appraisal well – we have to finalise the analysis of that. We are in the technical phase of evaluating and getting to know the reservoir and the conditions that we have there. After that, we will talk about development, and only then can we have an idea of costs.”
Even though the Shuwaihat gas field is not as big as the Shah, it is a productive asset for ADNOC, mainly because of smaller gas reserves that have been found nearby. “The Shuwaihat project may not necessarily produce as much as the Shah project. But we see that Shuwaihat also has some sister reserves,” Salge revealed.
“If we are successful in the first phase of developing Shuwaihat, finding the right innovations and tools to produce cheaper, efficient and sustainable sour gas, then we can use similar [methods] to extract from the sister reserves. We would also be adding a lot of volume and substance to it. This might not happen soon, but I hope it will eventually.”
