ABERDEEN’S Oil and Gas Technology Centre is rightly calling for technologies to transform the way we develop the remaining UKCS hydrocarbon reserves. That prompted me to think about transformational technologies I’ve seen implemented in my 40+ year career as a chemical engineer in oil and gas. Could we learn future direction from past innovations?
Three transformational technology areas stand out for me.
Advances in extended reach drilling have, in my opinion, done more than any other technology to transform the commercial development of oil and gas reserves. Horizontal wells have made an enormous contribution to reducing costs and increase drainage quantities from a single well penetration. When I started in the industry, the high angle well was state of the art and the furthest that could be reached was around 5,000 m.
I have been involved with the development of many oil and gas fields and have two standout examples where the horizontal well delivered a transformation. They were both in the 80s. Firstly, I was working on the Harding field for Britoil (at that time it was called Forth following the company convention of using Scottish rivers as field names) and the concept was two drilling centres – a North and South Platform. Two platforms were required to allow for high angle well coverage of the area of the field. At the time, horizontal wells were in their infancy, however the drillers took the view that by the time the two platforms were designed, constructed and installed horizontal wells would be proven technology. The adoption of horizontal wells allowed for the development concept to be changed to a single platform – an enormous cost saving.
Secondly, when working for BP, further development of Wytch Farm’s Sherwood Reservoir was under investigation. The Sherwood reservoir extended into Poole Bay, offshore from Bounemouth. It was not thought possible to drill from shore and reach the preferred production zones. The creation of an artificial island with a drill rig and process plant was the front-running concept. Whilst of no real concern from engineering considerations, the creation of an artificial island within view of the shore was seen as a very difficult concept from a permits and consents viewpoint. The visual intrusion of the island was predicted to arouse fierce local objection and was considered to be a very real risk to project viability.
Again the drillers proposed that the far reaches of the reservoir could be attained by long horizontal wells drilled from shore. Adopting that well strategy allowed the artificial island concept to be dropped, the project was de-risked and successfully developed with land-based extended-reach wells. Indeed, for many years, one of the wells held the world length record at over 10,000 m – inconceivable in the early 80s.
Coming from onshore petrochemicals, the first time I saw this concept I thought: –“What, you’ve put the process plant above the tank farm!” Onshore tank farms are kept a considerable distance from hazardous process facilities, not something you can do offshore.
The FPSO concept is testament to the safety engineer’s ability to identify and manage hazards. Advances in hydrocarbon release and fire and explosion modelling allowed this concept to be designed to minimise the residual risk, thereby allowing for the development of oil and gas fields that would have otherwise been commercially stranded.
It is perhaps also worth mentioning the innovative financial engineering associated with this concept – the operating and lease agreements.
In the early 80s I recall mentioning the option of subsea to my then BNOC (British National Oil Company), Texan engineering manager. “Tom, wellheads should be where God intended them – where you can touch them”. At the time he was correct, our analytical ability to model the very complex flow and chemistry interactions in long-distance, subsea pipelines, transporting unprocessed reservoir fluids was too basic to allow for confident assessments.
Subsea though was seen by the industry as a transformational technology and significant effort and R&D funding was released to enable the delivery of the flow assurance understanding required to de-risk the subsea concept. I managed an R&D budget for BNOC/Britoil and spent a large part of my career on developing flow assurance technologies. 30 years later, as technical director of Genesis, the tools my engineers have to analyse subsea flow assurance issues is just jaw dropping. As we know, for the past 25 years, subsea has been the basis for most new UKCS developments thanks largely to a transformational understanding of the physics and chemistry going on inside subsea pipes. For example, Total’s Laggan-Tormore development would not be possible without advances in flow assurance.
It might be worth mentioning a technology we identified in the early 80s that a generation later we have only part delivered on – automation. The concept of fully unmanned gas and oil processing facilities was the vision but we are not there yet.
Although not unique to the oil and gas industry, I feel I also have to comment on the transformation that computer aided design has delivered. As someone who started his first job at ICI Petrochemicals with a desk complete with a slide rule and log tables, the computational abilities of a desktop PC are astonishing. Used efficiently, software has transformed engineering design. However, I do think that we often use computing powers to do a lot of unnecessary things very quickly. In my view, coming from a generation where we could see the design methods we were following made for a greater understanding of the key engineering areas to be considered. In turn this resulted in productive analysis. The methods used today are embedded in computer code that we don’t see, thus rendering insight more difficult;visibility on the key variables, the uncertainties and the importance of assumptions. And, of course, we must be careful of the “computer says no” attitude.
So what might be the next transformational technology? In the North Sea, the Murchison Field was recently decommissioned, leaving behind around 30% of the original oil. For a field the size of Murchison, that is around 250m bbl. An accumulation much larger than anything we are likely to develop or find in the future. This will be the same for most of the first and second generation mega fields in the North Sea – Ninian, Thistle, Dunlin etc –after production stops we are leaving behind a huge amount of unrecovered reserves.
Obviously if those unrecovered reserves were easily developed the industry would do it. We have pushed and prodded as much oil out as technology and costs will allow. The industry has for many years researched a range of enhanced oil recovery (EOR) techniques to produce some of this locked oil. This work includes polymers which help injected water find the oil trapped in the hard-to-reach areas, low salinity waterflood which reduces the oil-rock adhering forces, surfactants which act much like soap cleaning oil from the rocks adding heat to help the oil flow and injecting high pressure gas which swells the residual trapped oil and makes it easier to move. These techniques have uncertain effectiveness; they also tend to be expensive and accordingly their use has been limited (see Figure 1).
There is though, an EOR technique that appears to have been given little attention; microbial enhanced oil recovery (MEOR) – the use of microbes to help release the trapped oil. One microbial technique that would be truly transformational is the use of methanogens to transform the trapped oil into methane (natural gas). Methanogens are present in the stomach of ruminants and in wetlands, producing methane in cow farts and marsh gas (methane). How would it work in an oilfield? Firstly a methanogen capable of withstanding oil field conditions and eating oil and making gas at a rate that would make the process viable would have to be developed. No mean feat but assuming success, then prior to cessation of production and decommissioning, the field would be flooded with the methanogens and nutrients. The microbes would subsequently colonise the oilfield and metabolise the trapped oil converting it to methane. The much more mobile bio-produced methane gas would migrate upwards, accumulating as a large gas cap. The gas cap would be then produced through the existing infrastructure. A potentially low cost, highly effective hydrocarbon EOR recovery option for a mature province like the UK (see Figure 2).
Let us assume that MEOR is seen as a transformational technology for the UK, how would the research be funded? The OGTC has £180m (US$232m) to spend over the next ten years. Sounds like a lot but it is only the price of two or three complex high pressure/ high temperature production wells. Supplemented by industry funding and spread over a range of R&D areas, will this funding be sufficient to progress a transformational technology?
When I recall the UK’s funding of subsea technologies in the 1980s the answer is no. At that time the development of the required flow assurance technologies was taking place in a number of centres – Atomic Energy Authority (AEA), Imperial College, British Hydromechanics Research Association, National Engineering Laboratory, Strathclyde and Heriot Watt Universities. Single oil company and Joint Industry Projects were initiated with typical spends being five- and six-figure sums. Although I can’t be sure, I would estimate the total UK subsea and flow assurance R&D spend to be less than £50m during a five-year period.
The UK had superb flow assurance practitioners, particularly at AEA due to the complexity of nuclear reactor cooling and steam system design. A key decision was made to convert the then TRAC model (Transient Reactor Analysis Code) to PLAC – Pipeline Analysis Code for Oil and Gas. A spot-on idea but we didn’t invest in sufficient funding.
Norway, however, did the right thing and invested an order of magnitude more than the UK in subsea technologies. The old adage “you get what you pay for” springs to mind as Norwegian flow assurance models and subsea hardware now dominate the market.
If we do identify a transformational technology let’s fund it properly.