Steam now plays a critical role in the recovery of oil throughout the world. There are a variety of technologies being employed depending upon the geology of the oil deposits. Enhanced Oil Recovery or EOR is widely used throughout the US and Middle East for increasing the amount of crude oil that can be extracted from an oil field.
A popular form of this technology involves thermal or steam injection. Using steam injection, as much as 30 – 60% or more of a reservoir’s original oil can be extracted. In this technique, steam is used to introduce heat into a reservoir by being pumped into a well. The steam eventually condenses to hot water; first evaporating the oil as steam and then expanding the oil as hot water. The viscosity of the heated oil drops and the expanding heated oil is pumped from the well at a site adjacent to the steam injection well.
Typically, the steam is produced through heating in a boiler using either natural gas or diesel. Recently solar has been employed to generate steam and is proving to be a viable alternative to gas fired steam production, although the capital costs to construct concentrated solar power plants (CSP) are not insignificant, nor are CSPs mobile.
Solar's cost advantage varies by location and the price of fuel however it is substantially less than gas-fired steam. Glasspoint Solar is involved in major Gigawatt solar heating plant construction throughout the Middle East. The global EOR market was valued at $60 billion in 2014, and is expected to experience a compound annual growth rate of about 25 per cent to reach $225bn in 2020, according to Zion Research of the United States. Thermal injection dominates the sector, accounting for more than 40 per cent of the total EOR market in 2014.
The other dominant form of oil recovery involving steam is known as Steam Assisted Gravity Drainage or SAGD. This method of recovery is used for producing heavy crude oil and bitumen. The method employs a pair of horizontal wells drilled into the oil reservoir, one a few meters above the other. High pressure steam is continuously injected into the upper wellbore to heat the oil and reduce its viscosity, causing the heated oil to drain into the lower wellbore, where it is pumped out. SAGD is used extensively in the recovery of oil from primarily oil and tar sand deposits in Canada, especially where surface excavation is no longer possible.
Alternative methods to SAGD are Cyclic Steam Stimulation (CSS) and High Pressure Cyclic Steam Stimulation (HPCSS). Both of these methods involve pumping steam injection down a single well bore to fracture and heat the formation over a time period ranging from weeks to months. The flow of the injection well is reversed, allowing oil to be pumped from the well bore.
It is significant to note that 35% of oil imported into the US comes from Canada and almost all of that oil originates in oil and tar sands. While natural gas was widely used to heat the injected steam, the value and demand for this resource begs for cheaper, quicker, and better technology.
The recent technological developments of Cavitation Energy Systems with respect to the generation of steam create a revolutionary opportunity for the oil recovery industry. The cost of generating steam at the wellhead using conventional means is significant and represents a major cost component to the per barrel oil recovery. The amount of additional oil recovered from oil reservoirs (30 – 60%) is very substantial; however this is offset by the high cost of producing the steam that gets forced underground to liquefy viscous petroleum.
A ten percent or more reduction in the per barrel cost of oil recovery would represent an enormous opportunity. In so many cases, particularly where recovery break even costs hover around $50 per barrel, a 10 to 20% cost reduction would make a vast amount of US and foreign oil, heretofore cost-wise unobtainable, economically viable.
Cavitation based steam, (see the technology and science behind this method) is vastly cheaper than fossil fueled boiler fired steam. A CES system capable of delivering 2000lbs. of continuous steam per hour at a cost of less than 100kw/hour can be packaged in a standard 40’ shipping container and driven inexpensively, directly to the well head or adjacent injection well.
This represents an enormous opportunity for the oil recovery industry ranging from the tar sands of Canada to the reservoirs of the Middle East. So many reservoirs, with vast reserves, which no longer yield free flowing oil, can be exploited for a fraction of the conventional recovery cost.
Cavitation generated steam is a technology based on the unusual physics of cavitation. High pressure water, saturated with cavitation bubbles, is forced at high speed into the cavitation impact chamber. When the billions of bubbles are crushed, tremendous heat is generated contributing to the steam production. This result is a consequence of the fluid dynamics of high speed water flow and is a well-established physical principal. Collapsing cavitation bubbles experience extreme heating of their internal water vapor (> 5000 degrees K) contributing to the overall heating and steam production.