Heavy Oil Transportation
Viscosity is the measure of resistance of a fluid to shear or tensile stress. In other words, lesser the viscosity of a fluid easier it is to move it. Another way to think about viscosity is to think of it as the internal resistance within a liquid to movement akin to a fluid friction. Nearly all liquids have some resistance to movement and the branch of science studying this phenomenon is called Rheology.
Crude oil or petroleum is a naturally occurring, toxic, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights, and other organic compounds, that are found in geologic formations beneath the Earth's surface. Generally accepted theory of crude oil and natural gas formation is that over geological times ancient biomass (kerogen) is heated and pressurized underground, finally converting to various grades and degrees of usable hydrocarbons.
Viscosity in crude oils is a direct function of the overall constituent hydrocarbons and can range from a 200 cP (centipoises) for light crude oil to over 500,000 cP for Cold Lake bitumen. This great variability results in continuous development efforts by major oil and gas firms in enhanced oil recovery methods. A persistent problem in the thermal recovery of bitumen or very heavy oil is the very low mobility at the reservoir conditions. Despite improvements on thermal recovery methods such as Steam Assisted Gravity Drainage (SAGD) and Toe to Heel Air Injection (THAI), transportation of bituminous crude is highly problematic.
In order to transport high viscosity crude oil from Western Canada to gulf refineries, industry relies on addition of C4+ hydrocarbons (diluents) or synthetic crude blending. Both of these solutions however create different economical problems, diluents are quite rare in Alberta and are being sold at a substantial premium as a result of increasing market demand; synthetic crude results in a highly aromatic oil which makes it less valuable from refining point of view. Most refineries reduce synthetic crude to less than ten percent of the diet which makes a complete reliance on advanced gasification technologies unsustainable.
An industrial value range for losses attributable to ultra high viscosity of bituminous crude oil is between $6 - $10 per barrel. Any viscosity reduction mechanism that does not need C4+ paraffinic hydrocarbons as diluents and simultaneously does not depend on synthetic crude technologies is in very high demand. Considering the ultra rapid expansion of Canadian Oil Sands and potential expansion of Venezuelan Orinico Belt hydrocarbon plays will only improve the importance of novel crude oil transportation technologies for energy industry.
Oil sands are mined and processed to generate oil similar to oil pumped from conventional oil wells, but extracting oil from this matter is more complex than conventional oil recovery. Oil sands recovery processes include extraction and separation systems to separate the bitumen from the clay, sand, and water that make up the oil sands. Bitumen also requires additional upgrading before it can be refined. Because it is so viscous, it currently requires dilution with lighter hydrocarbons to make it transportable by pipelines.
State of the Art
Oil-soluble viscosity reducers, together with water-soluble emulsifying viscosity reducers is considered economically and technically the most valuable solution to viscosity problems of bituminous crude oils. The technology development of oil-soluble viscosity reducer has been very slow. One of the main reasons is that the viscosity reduction mechanism of such a reducer has not been fully understood. Today, the viscosity reduction effect of existing products in the market cannot fully meet the requirements of bituminous oil exploitation. Therefore, the common methods of applying viscosity reduction technology are to add light hydrocarbon fractions (diluents) or use light oil that is mixed with a certain concentration of oil-soluble viscosity reducer (PetroBras). So it is highly significant to carry out research on viscosity reduction mechanisms and develop oil-soluble viscosity reducers that meet the requirement of thick oil exploitation, extraction and transportation.
Brazilian industrial researchers mostly concentrated on using a combination of refined hydrocarbons (such as kerosene and diesel) in combination with biodiesel or virgin oils either as an injection to the reservoir or as subsequent diluent. However biodiesel is not produced in very large quantities in bitumen production areas and at this time there are no transportation mechanisms such as trainlines or specialized pipelines that can carry required quantities.
A canadian academic research group studied the possibility of adding two oxygenates; methyl-tert-butyl-ether (MTBE) and tert-amyl-metyhl-ether (TAME). Both MTBE and TAME are being heavily used as gasoline additives and investigator’s aim was clearly to add these additives earlier in the production process in order to make use of their viscosity reducing and asphaltene precipitation prevention effects. Their invention clearly does not solve the diluents transportation problem as both of these oxygenate products are produced at gulf region and will require specialized pipelines for transport as well as reducing oxidative resilience of crude oil.
There have been a few attempts at using polymer-modified-bitumen (PMB) as a core technology platform for eliminating viscosity problem of the bitumen. However results have been less than satisfying as polymers employed in the process interferes with most refinery chemical processes. This type of a solution is currently being considered by several oil and gas producers.
Diluent replacement products research has been ongoing for the last few decades. There are a few promising directions invented over the years but nothing that is both oil and water soluble as our diluent family. Our first, second and third generation inventions incorporate the best possible outcomes of industrial and academic research while not suffering from their inherent drawbacks.
Quantum Ingenuity's Heavy Oil Transportation Technology
Quantum Ingenuity developed a novel diluent replacement product that mimics identical performance characteristics to NGLs in terms of diluting bitumen. Our system can be utilized at a cost of approximately half of current diluent application costs ($3-$5 vs $6-$10 per barrel). Our third party validated tests indicate that we can convert a 2,600,000 cST and 1014 kg/m3 (7 API) Athabasca bitumen to 1,000 cST and 923.5 kg/m3 (24 API) utilizing our system. These values indicate that we can take very highly viscous bitumen and convert it to a pipeline acceptable product while simultaneously reducing carbon footprint and environmental impact very substantially.
Moreover, diluent replacement system can be deployed with minimal capital expenditure and stay in production independent of crude oil prices. It is our ardent belief that once industry adoption takes place, there will be no place for expensive NGLs in heavy oil production.