Abstract:
A chemical delivery system which utilizes multiple techniques to achieve a suitable chemical purge of the chemical delivery system is provided. A purge sequence serves to purge the manifold and canister connection lines of the chemical delivery system prior to removal of an empty chemical supply canister or after a new canister is installed. More particularly, a purge technique which may utilizes a variety of combinations of a medium level vacuum source, a hard vacuum source, and/or a liquid flush system is disclosed. By utilizing a plurality of purge techniques, chemicals such as TaEth, TDEAT, BST, etc. which pose purging difficulties may be efficiently purged from the chemical delivery system. The chemical delivery system may also be provided with an efficient and conveniently located heater system for heating the chemical delivery system cabinet.
Abstract:
A chemical delivery system which utilizes multiple techniques to achieve a suitable chemical purge of the chemical delivery system is provided. A purge sequence serves to purge the manifold and canister connection lines of the chemical delivery system prior to removal of an empty chemical supply canister or after a new canister is installed. More particularly, a purge technique which may utilizes a variety of combinations of a medium level vacuum source, a hard vacuum source, and/or a liquid flush system is disclosed. By utilizing a plurality of purge techniques, chemicals such as TaEth, TDEAT, BST, etc. which pose purging difficulties may be efficiently purged from the chemical delivery system. The chemical delivery system may also be provided with an efficient and conveniently located heater system for heating the chemical delivery system cabinet.
Abstract:
A method of emptying vessels containing dispersions, solutions or suspensions of polymers in which during the emptying process the liquid medium also used to take up the polymers into the dispersion, solution or suspension is passed into the space within the vessel that is not filled by the solution, dispersion or suspension, wherein the liquid medium used to take up the polymers into the dispersion, solution or suspension is introduced in vapor form.
Abstract:
Containers for ultrahigh purity chemicals having aspect ratios of greater than 3:1 and methods of making the same from seamless electropolished stainless steel tubing are described. Chemical delivery systems for semiconductor fabrication processes that utilize these high aspect ratio containers also are described.
Abstract:
A method for treating a liquid flow to be cleaned passing through a flow line into a flotation plant including passing a portion of the liquid flow to be cleaned from the flow line along a first branch line into a pump. The suction capacity of the pump is regulated to draw in a direct flow of gas so that the pump sucks the gas as a direct flow. The drawn-in direct flow of gas is then mixed with the liquid flow in the pump and passed along a discharge pipe of the pump into a mixing part wherein the discharge pipe ends in a pressure release. The remaining portion of the liquid flow to be cleaned from the flow line is then passed along a second branch line into the mixing part. A liquid flow is discharged from the pressure release, the liquid flow including gas bubbles containing dissolved gas. The remaining portion of the liquid flow to be cleaned is then mixed with the liquid flow discharged from the pressure release to obtain a resultant flow which is then passed along a mixing duct into the flow line and further into the flotation plant.
Abstract:
A highly reliable digital level sensor assembly is provided to replace optical and capacitance type sensors in high purity chemical delivery systems. The digital level sensor assembly is particularly useful in bulk chemical refill delivery systems for high purity chemicals employing a manifold that ensures contamination free operation and canister change outs with a minimum of valves and tubing.
Abstract:
A highly reliable digital level sensor assembly is provided to replace optical and capacitance type sensors in high purity chemical delivery systems. The digital level sensor assembly is particularly useful in bulk chemical refill delivery systems for high purity chemicals employing a manifold that ensures contamination free operation and canister change outs with a minimum of valves and tubing.
Abstract:
The present invention provides an agent dispenser, a method and an apparatus for introducing an agent into a liquid or gas where the agent is miscible with such liquid or gas. The agent dispenser comprises a hollow casing constructed of a material having a coefficient of cubical expansion that differs from the coefficient of cubical expansion of the liquid or gas. At least one opening is provided in the hollow casing for permitting the flow of the liquid or gas to and from the interior of the hollow casing. The dispenser contains the agent and the agent is introduced into the liquid or gas through liquid or gas drawn into and expelled from said dispenser as a result of variations in the internal pressure of the dispenser resulting from thermal expansion and contraction of the dispenser and its contents caused by variations in the temperature of the liquid or gas surrounding the dispenser.
Abstract:
A bulk material dosing or feeder device has at least one upright post mounted to a base and carrying a horizontal head section. A supply hopper is supported by the head section. Modular units such as a stirrer, a weigher or feeder or the like are vertically aligned, vertically below the hopper. At least one, preferably each modular unit is mounted on a respective swivel arm. The swivel arm is journalled to the upright post whereby the modular unit may be tilted into an operative position below the hopper or into an out position for easy access to and exchange of the modular units.
Abstract:
An improved system for performing an alkylation process and a method for handling liquid catalyst in an alkylation process. This improvement involves method and apparatus by which liquid alkylation catalyst contained in the alkylation process equipment can be transferred into a catalyst storage vessel without the need for venting excess pressure from the storage vessel to atmosphere. Through a combination of the physical arrangement of the process equipment and the storage vessel along with the addition of a pressure equalization line, apparatus is provided whereby certain process steps can be followed which allow the transfer of catalyst from the process equipment to the storage vessel without venting the storage vessel. The improvement comprises physically locating the catalyst storage vessel at a relative elevation below the alkylation proces equipment and providing a line to connect the vapor space of the storage vessel with that of a catalyst settling vessel in the process equipment.