摘要:
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 ("C.sub.cs.sup.O " and "C.sub.ss.sup.O ") for the circuit for each of the carboxylate and sulfonate classes of surfactants;monitoring the free surfactant concentrations ("C.sub.cs " and "C.sub.ss ") in the process water for an ore being processed;determining which of C.sub.cs.sup.O and C.sub.SS.sup.O 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.
摘要:
Two or more tar sand feeds are blended in specified proportions in combination with a specified dosage of NaOH to provide a slurry, having a free surfactant content dissolved in the aqueous phase of the slurry, which yields the maximum possible primary froth production from the hot water extraction process.
摘要:
The hot water process is sensitive to the nature of the tar sand feed, which varies. An alkaline process aid, usually NaOH, is normally added to the conditioning step of the process and is needed to obtain good bitumen recovery from most tar sand feeds. The invention is based on the discovery that, for a particular extraction circuit used, there is a single value of free surfactant content in the aqueous phase of the process slurry which will yield maximum primary froth recovery regardless of the type of tar sand feed used. The process in accordance with the invention therefore comprises: (a) determining, for a single tar sand type and the extraction circuit used, the free surfactant content in the aqueous phase of the slurry, which will yield the maximum primary bitumen forth recovery; (b) monitoring the free surfactant content in the aqueous phase of the slurry during subsequent processing of various types of tar sand feed in said circuit; and (c) varying the process aid addition to the slurry as the nature of the tar sand feed varies, to maintain said free surfactant content substantially at the level which leads to maximum primary bitumen froth recovery.
摘要:
Calcium sulphate is added to desanded tailings derived from a hot water extraction process for recovering bitumen from oil sand. Enough calcium sulphate (100 to 200 ppm) is added to remove naphthenates and sulfonates from the aqueous phase. As a result, the settling rate of the fines in the tailings is accelerated.
摘要:
A plug valve has an actuating stem which is non-integral with the valve plug. The actuating stem is axially movable with respect to the valve plug to compressingly and sealingly engage an external sealing member in response to fluid pressure. The plug wedges itself into sealing engagement in response to fluid pressure.
摘要:
A self-contained, operative, valving unit which includes a valve body having inlet and outlet ports, and a rotatable valve plug is securely though removably housed within a valve housing having inlet and outlet ports which are permanently secured to pipes through which the fluid media to be controlled is conveyed to and from the housing, and wherein the entire valving unit, per se, is received within a valving-unit-receptive bore of the valve housing with its inlet and outlet ports in cooperative, aligned, fluid tight relationship with respect to corresponding inlet and outlet ports interiorly of the valve housing whereby the flow of fluid media through the valve housing is controlled by the removable valving unit.
摘要:
A seal for a shaft in a structural body. The seal is configured to surround the shaft within said structural body. The seal has a flange making a gasket seal with the structural body. The seal has at least one portion distorted and stretched into a tapered configuration and into a tension-related sealing association with the shaft. The seal is made of a memory-retainable material. This memory urges the distorted and stretched tapered portion towards its original configuration, thereby enhancing the sealing association with the shaft.
摘要:
A fail-safe actuator mechanism has an actuator housing encapsulated within a tank which stores a pressurized fluid media. Ports of the actuator housing are put into selective fluid communication with both the interior and exterior of the encapsulating tank by a valve at selective pressures.
摘要:
A system for sampling material from a remote location which selectively collects a predetermined quantity of material in a valve disposed inside a container. This measured amount of material is transferred to a movable receiving carrier while the receiving carrier is in a sealed relationship with the valve to prevent leakage of the sample material outside the receiving carrier. The movable receiving carrier is transported via an elongated tubular structure to a location remote from the container.
摘要:
External and internal leakage of line media from a plug valve is prevented by the continuous application of a buffering media at all potential leak paths at pressure greater than the pressure of the line media.