Improvement of the bitumen extraction technology from bituminous sand deposits

Abstract

Today considerable experience in the development of tar sands is accumulated. However, well-known mining technologies do not cover the entire depth range of natural bitumen deposits. In addition, there are significant energy-intensive technologies and negative environmental impacts. In view of this, the purpose of this work is to improve the method of extracting natural bitumen in site for a deposit interval of 75 – 200 m and to substantiate the basic technological scheme of this method. The proposed method of extracting bitumen from poorly cemented reservoirs in the depth range of 50 – 400 m provides: creation of artificial mine working; the transfer of the rock into the water mixture composition under the action of high pressure jets of a heated mixture of water, a hydrocarbon solvent and a flotation agent; separation from the rock and concentration of bitumen in the production as a result of its heating, dissolution and flotation; selection of depleted bitum slurry from the mine working by gas lift method. The proposed method of extracting bitumen is the transfer of the rock at the site of its occurrence to the suspension condition on the excavation created by the hydraulic production method, separation and concentration of bitumen by dissolving it with a heated hydrocarbon solvent and a flotation agent (hydrocarbon reagents), and extraction in the composition of depleted rock slurry to the surface by the gas lift method. As the preliminary calculations show, the proposed method will allow the efficient extraction of bitumen and highly viscous oil from weakly cemented reservoirs in the depth range of 50 – 400 m. Also, the proposed technology creates the preconditions for the development of oil sands at a depth of 75 – 200 m since there is currently no effective technology for the interval. In addition, it can significantly reduce energy costs, environmental pollution and greenhouse gas emissions.

Analysis of the geotechnological potential of heavy oil/bitumen production based on the improved method of well hydraulic production

“…Based on the above analysis of the use of catalytic processes for the intensification of production of heavy oils and bitumen, it is advisable to consider the option of combining the technology proposed in [29][30][31] with the process of catalytic aquathermolysis. This improvement will not require modernization of the underground part of the extraction systemit is advisable to supply the catalyst together with the working fluid.…”

“…A feature of the technology presented in works [29][30][31] is the presence of temporary mining, the start of production immediately after the completion of drilling the horizontal part of the well without preliminary heating of the rock, the organization of production in the direction from the hole to the wellhead. This will make it possible to minimize unproductive losses of thermal energy into the surrounding rock and to maintain the temperature necessary for the implementation of catalytic aquathermolysis in the area of the hydromonitors operation.…”

“…On the basis of the elements of the technology of borehole hydraulic production in works [29,30], a method of extracting natural bitumen and high-viscosity oil for the entire depth interval of their occurrence was proposed, and in work [31] it was improved. The schematic diagram of the implementation of this method is presented in figure 1.…”

“…The schematic diagram of the implementation of this method is presented in figure 1. The method involves performing the following operations [31]: opening of the productive layer by horizontal wells; opening of rods with hydromonitors at the bottom of the well for washing out the mining production and its further development in the direction of the wellhead. Gradually, a mine is formed, which develops in the direction of the wellhead;…”

“…Thus, the technology described in works [29][30][31] allows solving a number of problems and shortcomings of the SAGD technology and its modifications. However, to increase competitiveness for industrial implementation, it is necessary to consider options for its further improvement.…”