Aramco researcher’s inspiration while tending his date tree leads to an award-winning innovation that has improved oil and gas drilling efficiency.
Date palm seeds can produce an LCM that is more reliable and cost-effective than previous solutions
For thousands of years, people in the Middle East have made a living from date palms, harvesting the fruit, and turning the leaves into baskets and mats. But, what connects Saudi Arabia’s ancient date plantations to Aramco’s oil and gas operations, which are less than 100 years old? The answer is date palm seeds, which it turns out could be an ideal material for increasing the efficiency of drilling oil and gas wells.
- Oil and gas drilling depends on lost-circulation materials (LCMs) to prevent expensive downtime
- Surplus date palm seeds can produce an LCM that is more reliable and cost-effective than previous solutions
- As well as solving a long-standing drilling problem, the innovation is supporting Aramco’s supply-chain localization efforts, and reducing waste
This discovery has not just improved drilling. It has also helped support our supply-chain localization efforts and reduce waste by utilizing a biodegradable local product in place of imports.
Locking Up the Loss Zones
To understand how date palms can play a role in improving drilling processes, it’s important to remember that drilling is still difficult work, regardless of how routine it may now appear. The pressure in the wellbore — the hole being drilled — must be maintained to keep the drilling process efficient, rock debris must be lifted to the surface, and the drill bit needs to keep turning smoothly.
All that is possible because of the drilling fluid, known as “drilling mud,” which is pumped through the drill pipe, out of the drill bit and then circulated back to the surface, pushing up the rock chips. Sometimes, though, this fluid escapes into porous “loss zones” in the rock, reducing circulation, slowing or even stopping the process, and causing costly delays. A prolonged stoppage could cost up to millions of dollars in terms of lost production and wasted manhours, so lost-circulation materials (LCMs) are added to the drilling fluid to create a seal that prevents the fluid escaping into these loss zones.
LCMs are made from different materials depending on the drilling conditions and the drilling fluid’s overall composition.
Each type has its own advantages and disadvantages, but the most common are LCMs made from calcium carbonate, which are inexpensive, but using too much can result in damage to the surrounding rock. Those made from polymers can be more effective, but are also more expensive. Aramco had historically used a ‘nut-plug’ LCM, a product made from walnut shells, that was imported from the U.S.
Getting the right LCM is particularly important in Saudi Arabia, because the porous rock types that have been so ideal for forming oil and gas reservoirs are also very likely to form loss zones. Since it is so easy for drilling fluid to be lost, better LCMs would increase efficiency and reduce costs and lost time.
Date palm tree
The Seed of a Great Idea
So where do date palms factor in? One weekend, Mohammad Amanullah, a senior researcher at Aramco’s Exploration and Petroleum Engineering Center — Advanced Research Center (EXPEC ARC), was tending his garden in Dhahran, and his attention fell on his large palm tree.
A part of tending to this tree involved regular pruning and clearing up fruit caps and other scraps after each season’s date harvest. And of course, after enjoying the dates, there were also the date seeds leftover. He began to wonder whether these seeds could potentially replace the walnut shells used in the LCMs Aramco imported.
His idea connected two of Saudi Arabia’s most vital industries, and if it was successful could transform the date industry’s waste materials into a new solution to long-standing challenges experienced during well drilling.
He and his team at EXPEC ARC began working on a prototype. They found a version that seemed promising, and they decided to test it against the nut-plug product Aramco had been using.
Date-based LCM
Dates Versus Walnuts
The new date-seed-based LCM performed as well as the existing one, or in some usage scenarios even better, thanks to a material toughness similar to the calcium carbonate already used by the industry, and mechanical properties similar to walnut shell.
In 2015, encouraged by these results, the team filed for patent protection on the idea of using dates seeds as an LCM.
Further research, in partnership with the Date Palm Research Center in al-Hasa, found that all date seed varieties the team tested during this process fell into a tight range of mechanical properties, regardless of the tree type or the growing region, so they were all likely suitable for use in an LCM.
ARC Plug materials in glass jars
Award-winning Innovation
Encouraged, the team worked with local partners to source and bulk-process date seeds according to the required specifications and named the new product ARC Plug. And in 2016, they began conducting field trials at three wells.
At the first, the rig team drilled a few thousand feet before experiencing partial fluid loss. They deployed ARC Plug and quickly saw a reduction in fluid loss. At the other two wells, each with differing drilling conditions, ARC Plug performed with similar success.
In fact, the results were so impressive that in 2017 ARC Plug would go on to win Technical Innovation of the Year at the Oil and Gas Middle East Awards.
Waste Not, Want Not
But the benefits go beyond improved drilling efficiency and effectiveness. ARC Plug is also proving beneficial for waste-reduction efforts in local industry. Many thousands of tons of date seeds (or kernels) are generated every year in Saudi Arabia.
Though these date seeds have potential value as a biomass source for energy production, and many new commercial uses are currently being explored and developed, from coffee to cosmetics, most seeds and palm waste was typically disposed of on date farms by burning, which creates pollution.
Another common disposal solution used for the seeds is burying them, which can often attract pests that hinder nearby plant growth or can negatively impact crop production. Using the waste seeds in ARC Plug helps reduce these unwanted issues, while also embodying the best ‘recycle and reduce’ principles of a circular economy.
Farmers collect dates
Eliminating the need for an imported product also eliminates the associated international transportation costs and carbon footprint.
Instead of shipping these materials around the world, the replacement date seed LCM can instead be transported just a few hundred kilometers from point of production to point of use, reducing the connected carbon emissions.
Innovation can often be found in unexpected places; ARC Plug has now entirely replaced the previously-used nut-plug LCM in Aramco’s field operations, saving the company and our drilling experts time and effort, and enhancing our processes and efficiency — and it all came from a quiet moment of inspiration granted in a garden.
— The Arabian Sun: February 04, 2024