Chemistry: electrical and wave energy – Processes and products – Electrical – or wave energy in magnetic field
Reexamination Certificate
1999-03-24
2001-03-20
Mayekar, Kishor (Department: 1741)
Chemistry: electrical and wave energy
Processes and products
Electrical, or wave energy in magnetic field
C204S157200
Reexamination Certificate
active
06203669
ABSTRACT:
FIELD OF THE INVENTION
The present invention pertains generally to systems and methods for the remediation of nuclear waste. More particularly, the present invention pertains to systems and methods which segregate nuclear waste into high level radioactive waste, low level radioactive waste and non-radioactive waste for separate handling and an appropriate disposal for the particular level of radioactivity. The present invention is particularly, but not exclusively, useful as a system and method for separating nuclear waste atom by atom.
BACKGROUND OF THE INVENTION
There is almost universal agreement that nuclear waste presents a global problem of immense proportions. Nevertheless, despite this awareness, the exact extent and possible ramifications of the problem are still somewhat undefined and are not fully appreciated by the public. All agree, however, that something must be done. The problem is further complicated by the fact that, heretofore, there has been no completely acceptable solution for the disposal of nuclear waste. Stated differently, the costs and the risks involved are generally unacceptable. Using conventional technology, the costs for remediation of the nuclear waste in this country alone is astronomical.
At the present time, nuclear waste is being temporarily stored in hundreds, and possibly thousands, of containers at various sites throughout the world. The total bulk of this nuclear waste is easily appreciated when it is realized that one container alone may hold as much as one million gallons of nuclear waste. Clearly, the volume of nuclear waste which requires special disposal is enormous. The problem is further complicated by the fact that a significant portion of the nuclear waste is classified as high level waste which requires special handling and extraordinary safeguards.
One form of disposal for nuclear waste which has gained some degree of acceptance in the nuclear waste remediation community involves a process known as vitrification, or glassification. In a vitrification process, the nuclear waste is absorbed and incorporated into glass for subsequent disposal. Present day vitrification techniques, however, face at least two significant difficulties. Most importantly, under present practice there is no effective way to differentiate between high level waste, which requires special handling, and low level waste which can be disposed of in a more conventional manner. Consequently, whenever high level waste is involved, the entire volume of nuclear waste, including both high level and low level waste, is treated the same way. As indicated above, the total volume of this waste is significant. Second, due to the large volume of waste that must be handled as high level waste, treatment and disposal may require decades to accomplish.
It happens that of the entire volume of nuclear waste, only about 0.001% are the radionuclides which make the waste radioactive. As recognized by the present invention, if the radionuclides can somehow be segregated from the non-radioactive ingredients of the nuclear waste, the handling and disposal of the radioactive components could be greatly simplified.
In light of the above it is an object of the present invention to provide a system and method for nuclear waste remediation which separates and segregates the radionuclides from the non-radioactive elements in the waste. Another object of the present invention is to provide a system and method for nuclear waste remediation which effectively vitrifies high concentrations of radionuclides for subsequent disposal. Still another object of the present invention is to provide a system and method for nuclear waste remediation which uses an in-line continuous process that requires minimal material manipulation. Yet another object of the present invention is to provide a system and method for nuclear waste remediation which is relatively easy to manufacture, simple to use and comparatively cost effective.
SUMMARY OF THE PREFERRED EMBODIMENTS
A system and method for extracting radionuclides from radioactive waste relies on the general notion that radionuclides in the waste are elements which have relatively high atomic weights (e.g. A≧70). Based on this premise, in accordance with the present invention, radioactive waste is first vaporized and then ionized to create a multi-species plasma. Due to the fact that the ingredients of the nuclear waste may not be known, it is considered that the resultant multi-species plasma will include electrons, light ions (e.g. A<70) and heavy ions (e.g. A≧70). The multi-species plasma is then accelerated to create a fluid stream in which the light ions and heavy ions all have substantially the same velocity. Once the uniform velocity fluid stream is created, particles in the stream are decelerated and segregated according to their respective inertia. The segregated heavy ions are then collected and vitrified for subsequent disposal. The specifics of the processes involved in the present invention are best appreciated by considering the various system components.
In overview, the present invention is an in-line system for the continuous processing of radioactive waste which sequentially comprises a loader/transporter, a plasma processor, a nozzle, an inertial separator and a collector/disposer sub-system. For the present invention, in accordance with well known practices, the vaporization and ionization of the radioactive waste are accomplished in the plasma processor in a high vacuum environment. This high vacuum environment (i.e. very low pressure environment) is in the range of a few microbars (e.g. 2-5 &mgr;bar). To begin the process, the transfer of radioactive waste into the high vacuum environment of the plasma processor is accomplished by the loader/transporter section of the system.
The loader/transporter section of the system for the present invention includes a substantially hollow U-shaped tube. Specifically, one end of the U-shaped tube (the first end) is exposed to atmospheric conditions while the other end (the second end) is exposed to the high vacuum environment of the plasma processor. Further, the tube itself is filled with a liquid transport medium, such as Octoil, which makes the assembly function like a manometer. In operation, a canister of radioactive waste is lowered through an opening at the first end of the tube and into the transport medium. The canister is then passed down the leg of the tube (the first leg) in the transport medium. Next, the canister is transferred through the transport medium across the base portion of the U-shaped tube by a series of rollers. After traveling across the base portion, an elevator raises the canister up through the other leg (the second leg) of the U-shaped tube. This raising action by the elevator lifts the waste filled canister out of the transport medium, and into the high vacuum environment. The canister is then transferred through a chute on a series of rollers which places it into position for subsequent processing in the plasma processor. Additionally, during transfer of the radioactive waste canister through the loader/transporter section of the system, the canister can be perforated by a punch. This punching action releases gases of the volatile materials that are in the waste (hereinafter generally referred to as “volatiles”) and allows them to be collected and held in a volatile holding tank for subsequent use in the plasma processor.
The plasma processor of the present invention is essentially a hollow tube which has two open ends. One of these ends is connected in fluid communication with the chute of the loader/transporter, and another end is connected in fluid communication with the nozzle. Between the chute and the nozzle, a portion of the plasma processor tube is established as a plasma chamber which includes a substantially cylindrical shaped dielectric section that is positioned between two stainless steel cylinders. A radio-frequency (rf) antenna is positioned around the dielectric section of the plasma chamber, and a solenoid magnet is positioned around bo
Archimedes Technology Group, Inc.
Mayekar Kishor
Nydegger & Associates
LandOfFree
Nuclear waste separator does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Nuclear waste separator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nuclear waste separator will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2543572