Monitoring surfactant content to control hot water process for tar sand
First Claim
1. In the hot water process for extracting bitumen from tar sand of varying nature in an extraction circuit, said process comprising conditioning the tar sand by slurrying it with hot water and alkaline process aid and agitating it, diluting the conditioned slurry with additional hot water, and retaining the diluted slurry in a primary separation vessel to produce an underflow of solids and an overflow of primary bitumen froth, the improvement comprising:
- (a) determining for the circuit involved a measure of the critical equilibrium free carboxylate-type surfactant concentration ("Ccso "), in the process water, at which maximum primary froth recovery occurs;
(b) determining for the circuit involved a measure of the critical equilibrium free sulfonate-type surfactant concentration ("Csso ") in the process water, at which maximum primary froth recovery occurs;
(c) determining whether the diluted slurry undergoing processing is one from which recovery of primary froth is first predominantly influenced by the concentration in the process water of free carboxylate-type surfactants or free sulfonate-type surfactants;
(d) in the case where the carboxylate-type surfactants first dominate, adjusting process aid addition to the process to bring the equilibrium free carboxylate-type surfactant concentration in the process water toward Ccso ;
(e) in the case where the sulfonate-type surfactants first dominate, adjusting process aid addition to the process to bring the equilibrium free sulfonate-type surfactant concentration in the process water toward Csso ;
and repeating steps (c), (d) and (e) on an on-going basis to establish a control method for maximizing primary froth recovery.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention is based on the following:
(1) that when tar sand is conditioned and diluted in the hot water extraction process, there are two classes of anionic surfactants (originating from carboxylate and sulfonate groups) present in the process water;
(2) that each of these surfactants has the potential to dominantly influence the maximizing of primary froth production by the process;
(3) that it is possible for a particular extraction circuit to determine the critical free surfactant concentration in the process water at which primary froth extraction is maximized for each of the two classes of surfactant;
(4) and that it is possible to determine which of the two classes of surfactant will first (that is, at lowest NaOH addition) dominate the process when a particular tar sand feed is being processed.
The present invention therefore involves:
determining the critical free surfactant concentrations ("CcsO " and "CssO ") for the circuit for each of the carboxylate and sulfonate classes of surfactants;
monitoring the free surfactant concentrations ("Ccs " and "Css ") in the process water for an ore being processed;
determining which of CcsO and CSSO occurs at a lower NaOH addition;
and then adjusting NaOH addition to the extraction process to bring the first dominating surfactant concentration toward the critical concentration value.
23 Citations
1 Claim
-
1. In the hot water process for extracting bitumen from tar sand of varying nature in an extraction circuit, said process comprising conditioning the tar sand by slurrying it with hot water and alkaline process aid and agitating it, diluting the conditioned slurry with additional hot water, and retaining the diluted slurry in a primary separation vessel to produce an underflow of solids and an overflow of primary bitumen froth, the improvement comprising:
-
(a) determining for the circuit involved a measure of the critical equilibrium free carboxylate-type surfactant concentration ("Ccso "), in the process water, at which maximum primary froth recovery occurs; (b) determining for the circuit involved a measure of the critical equilibrium free sulfonate-type surfactant concentration ("Csso ") in the process water, at which maximum primary froth recovery occurs; (c) determining whether the diluted slurry undergoing processing is one from which recovery of primary froth is first predominantly influenced by the concentration in the process water of free carboxylate-type surfactants or free sulfonate-type surfactants; (d) in the case where the carboxylate-type surfactants first dominate, adjusting process aid addition to the process to bring the equilibrium free carboxylate-type surfactant concentration in the process water toward Ccso ; (e) in the case where the sulfonate-type surfactants first dominate, adjusting process aid addition to the process to bring the equilibrium free sulfonate-type surfactant concentration in the process water toward Csso ; and repeating steps (c), (d) and (e) on an on-going basis to establish a control method for maximizing primary froth recovery.
-
Specification
-
- Resources
-
Current AssigneeCanadian Occidental Petroleum Ltd. (Cnooc Limited), Esso Resources Canada Ltd. (Exxon Mobil Corporation), Alberta Energy Co. Ltd. (Ovintiv Canada ULC)
-
Original AssigneeCanadian Occidental Petroleum Ltd. (Cnooc Limited), Gulf Canada Ltd. (ConocoPhillips), Esso Resources Canada Ltd. (Exxon Mobil Corporation), Hbog-Oil Sands Limited Partnership, In Right Of The Province Of Alberta Her Majesty The Queen, Alberta Energy Co. Ltd. (Ovintiv Canada ULC), PanCanadian Petroleum Ltd. (Ovintiv Canada ULC), Petro-Canada (Yemen), Inc. (Suncor Energy Incorporated)
-
InventorsSmith, Russell G., Schramm, Laurier L.
-
Primary Examiner(s)Pal, Asok
-
Application NumberUS07/001,258Time in Patent Office1,567 DaysField of Search208/391, 208/DIG. 1US Class Current208/391CPC Class CodesC10G 1/047 Hot water or cold water ext...
