Direct Pumping of Nuclear Waste
Typically motivated by pressurised water, Liquid Jet Solids Pumps can be used to entrain and transfer radioactive waste from settlement tanks / ponds. Liquid is often used to transport radioactive slurries in order to maintain velocity within long discharge pipelines and thereby prevent solids settlement. When pumping abrasive slurries, materials are typically stainless steel complete with ceramic internals.
Buffer Storage Application
Following on from the Direct Lift Ejector, the Transvac Air Ejector (AJE) again uses compressed air as the motive to draw air from the system. As is shown in the diagram on the right.
Slurry Lift Application
For this application Transvac Liquid Jet Solids Pumps are installed above the radioactive slurry. In operation ‘Pulse Jets’ submerged in the slurry agitate an area around the suction ‘leg’ of the Liquid Jet Solids Pump allowing it to transfer slurry to reception tanks elsewhere on site. As the tank slurry is removed liquor is added to the tank to maintain a constant head. The Jet Pumps include Transvac ceramic internals to resist wear.
For this application Transvac Liquid Jet Solids Pumps complete with a special fluidising jet system are to be submerged in the radioactive slurry. In operation the fluidising jets agitate an area around the suction ports of the Jet Pump allowing it to transfer slurry to reception tanks elsewhere on the site. As the tank empties the Jet Pump and fluidising jets are gradually lowered. The Jet Pumps include Transvac ceramic internals to resist wear.
Direct Transfer Storage Application
Transvac Air Jet Syphons are used to decant (directly transfer) radioactive liquor from cell sumps into the BSV tank as shown in the diagram. Using compressed air as the motive fluid enables the transportation of radioactive liquor without adding any extra fluid to the quantity handled. Gas is not an effective medium for directly entraining and pumping liquids. It can only be used as the motive fluid for Air or Gas Jet Syphons when entraining and pumping small quantities of liquids / slurries over short distances. Steam is a very effective medium to motivate Ejectors when directly pumping radioactive slurries over short distances.
One advantage of using steam is that it is easy to provide and adds very little additional liquid to the radioactive slurry being pumped, which can be major benefit for downstream processes. Typically discharge pressures would be >2 barg.
Indirect Pumping of Nuclear Waste
Steam, Air or Nitrogen can be used to motivate an Ejector to create a vacuum within a transfer vessel to draw in liquids / slurries. Steam, Air or Nitrogen is not in direct contact with the fluid being pumped. Once the volume of liquid reaches a pre-set level in the transfer vessel the Ejector is switched off. The vessel contents can then be simply drained by gravity to the discharge point. These systems are usually used for transferring small quantities of suction fluids.
Jet Mixers for Tank Mixing
Tank Jet Mixers provide a simple method of mixing and agitating tanks with no in-tank moving parts and no maintenance. Performance is controllable by adjusting the motive fluid flow provided by an external pump. Each Tank Jet Mixer is designed to suit the process mixing requirement and single Mixers or a number of mixers mounted on an in-tank manifold are available.
Transvac can offer the basic mixers or a complete system including pipework, pumps and valves. We can offer our Tank Mixers in a number of materials, including units internally lined with ceramics for improved abrasion resistance.