Oil Sands Frequently Ask Questions

January 23, 2020

Adam Robinson, B&W’s expert on the oil sands industry, answers some of your frequently asked questions. In describing the geology and challenges of the oil sands region, Adam provides a basic overview of the steam assisted gravity drainage (SAGD) process and how B&W has provided clean and effective technologies for oil extraction and refining.

What are the oil sands and where are they located?


Answer: The oil sands are a mixture of bitumen and sand and they’re located in Northwestern Canada, primarily Alberta. Bitumen is a type of heavy oil and when it is extracted it is put through an upgrader to produce crude oil that can then be sent to a refinery and processed like typical oil would be.

What are some of the challenges in the oil sands regions?


Answer: The oil sands region is fairly unique as it is a very remote region of the world. To get to the resources that are there, as these mines were being built, there were only dirt roads to get to them.

Over the years, infrastructure and highways have been built and expanded. But, through the years, the challenge when building large equipment is the challenge of transport. How do you get that piece of equipment to the remote location that you need it in? You’ll see many years ago at some of the mining sites, most of the equipment would be stick-built because of these shipping limitations.

Whereas now, we’ve shipped boilers in very large modules in what you might think of as LEGO blocks. When these pieces arrive at site, field installation is easy and the expensive labor in these regions is decreased so the project is more economical.

What are the current methods of extracting oil in the oil sands?


Answer: Oil sands mining can be used in certain areas of the oil sands where the sand is close enough to the surface that it’s economical to get to. Some of the oil sand is below the surface, within reason and we’re able to mine down to it. But once it gets so deep that mining becomes too expensive for the payoff for the oil, different methods that are referred to as in situ are used to get to that oil.

The major technology that is being used and being developed right now in the region is called SAGD. SAGD stands for Steam Assisted Gravity Drainage. The main idea behind the technology to access a deep deposit of oil sands, two wells will be drilled down into it, one well will be used to inject steam into the deposit, and then, once the deposit is heated up enough, the bitumen is viscous enough, it would drain out of the sand and be able to be collected by the sister well. That sister well would then pump the bitumen to the surface where it would be sent to an upgrader.

Can you tell us more about SAGD?


Answer: SAGD has been around commercially for about 20 years and throughout that time it has used OTSGs as the major steam generator.

An OTSG, or a Once Through Steam Generator, was specified because the quality of feedwater that can be used for those pieces of equipment is much less than a traditional drum boiler. In these cases where we’re in very remote regions that don’t have water treatment facilities, it made a lot of sense to use these OTSGs because they can handle lesser feed water quality and made the job a lot easier than building a water quality station like drum boilers may require.

What's a hot topic in the oil sands region right now?


Answer: There’s several projects being developed in the Alberta oil sands region. One of the driving factors behind that development is environmental regulation.

One of those regulations and one of those goals that the industry is striving towards is zero liquid discharge. When you look at an OTSG, it uses dirty feedwater, but it actually has to waste as much as 30% of that water in blowdown. Whereas if we look at a drum boiler, that number is typically less than 5%. As these new plants are developed and they’re using zero liquid discharge as a goal, there’s a push going towards drum boilers for any new developments.

Historically, what B&W products are used in the oil sands?


Answer: B&W has been involved in most of the steps in the extraction process when it comes to removing bitumen from the oil sands. Originally when the oil sands were developed, they were developed using surface mining technologies. Very large pieces of equipment would move through the oil sands and they would extract this material and the first portion that we got involved in was our Allen-Sherman-Hoff® (A-S-H®) material handling systems. Our A-S-H systems have a very large installed base in the oil sands. Everything from where the sand is dumped off and maybe pushed through a crusher to make it into smaller pieces, all the way through conveying systems and ultimately delivering that product to whatever piece of equipment is used to separate the sand from the bitumen. Then once you have bitumen, it moves from that facility into an upgrader. An upgrader is similar to a refinery. You take a product and you would refine it into another using very similar technologies from a steam standpoint.

One of the main byproducts of upgrading bitumen into crude oil is petroleum coke. Pet-coke, as it’s also named, is very similar in characteristics to coal when it comes to how you would handle it, how you would burn it as a fuel, and the types of environmental equipment that would be used on the backend.

B&W technology has been used on boilers, ash handling equipment, boiler cleaning equipment, and a full array of environmental equipment – precipitators, baghouses, flue gas desulfurization. Other types of boilers that are used both in upgraders and refineries are CO boilers. A byproduct of a few different processes in these facilities is CO gas that is typically very hot when it comes off a cracking unit. This hot CO gas would then be combusted, and it would be converted from CO to CO2. That would release a little bit of heat energy, combined with the heat energy already in that flue gas stream. We’re able to harness that energy in a boiler and produce steam. Similar to pet-coke boilers, there’s an array of environmental equipment on the backend of these boilers and B&W has supplied that equipment as well.

Finally, the most common piece of equipment that B&W has supplied to the oil and gas sector in Alberta is what we refer to as package boilers. This is the majority of the natural gas-fired boilers that we’ve supplied. Package boilers are pre-engineered. They’re small capacity and many oil and gas producers and plants in Alberta have them. When you get into larger capacities and bigger plants, we also build field-erected boilers that would still be fueled by natural gas, such as our PFI or TSSG.

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