Idaho Chemical Processing Plant low-activity waste grout stabilization development program FY-97 status report

Abstract

DISCLAIMER SUMMARYThe general purpose of the Grout Development Program is to solidify and stabilize the liquid low-activity wastes (LAW) generated at the Idaho Chemical Processing Plant (ICPP). It is anticipated that LAW will be produced from the following: 1) chemical separation of the tank f m high-activity sodium-bearing waste, 2) retrieval, dissolution, and chemical separation of the aluminum, zirconium, and sodium calcines, 3) facility decontamination processes, and 4) process equipment waste. Grout formulation studies for sodium-bearing LAW, including decontamination and process equipment waste, continued this fiscal year. A second task was to develop a grout formulation to solidify potential process residual heels in the tank farm vessels when the vessels are closed.For sodium-bearing LAW, the grouting of denitrated solids continues to be a viable process to achieve maximum volume reduction. A grout made with 35 wt% denitrated solids meets minimum strengths and leach resistance while reducing volume to 1 /5 the original volume. If volume continues to be a driving requirement, this process is the most effective.Two methods of grouting the liquid sodium-bearing LAW were found this year. The waste can be grouted if the pH is between 1 and 3 or if the pH is greater than 1 1. Both processes produce acceptable strength and leach resistance while increasing the volume by 1 1/2 times. The short-term tests look promising, but long-term tests (thermal cycling and immersion) need to be completed. If volume ceases to be a driver, these processes could become cost-effective.It was determined that the tank farm vessel process residual heels can be grouted if the heels are diluted. The heel could be diluted by repeatedly adding an equal volume of aluminum nitrate solution or water to the heel and jetting off as much solution as possible. It is recommended that premixed grout be used to displace heel so that it could be further jetted or pumped out of the tank. This method would remove as much heel as possible from the tank and leave a solid grout for tank closure.For FY-98, continued wasteform qualification is planned in the areas of compressive strength following sample immersion and thermal cycle testing. The grout formulations for both LAW and tank heels will be refined and characterized for mixture tolerances, order of addition, fluid flow, set time, cure rate, and heat of hydration. A grout pilot plant is planned for 2004 to test the equipment needed to concentrate, denitrate, and mix the grout and waste. Wasteform qualification testing is needed on full-scale disposal drums produced in the pilot plant to qualify the grout process and the grouted waste.... ACKNOWLEDGMENTS

Integrated AMP-PAN, TRUEX, and SREX Flowsheet Test to Remove Cesium, Surrogate Actinide Elements, and Strontium from INEEL Tank Waste Using Sorbent Columns and Centrifugal Contactors

“…Since the full separation option would includes removal of the TRU elements, it is unlikely a final LAW grout could be sent to WIPP, and therefore a "performance grout" and NRC Class A limits are likely required. Primarily due to the above considerations, development efforts at the INEEL have focussed on a number of potential grout formulations, which depend largely on the disposition route of the final product [15]. The current baseline for the full separation option would include concentration and denitration of the LAW fraction to convert the liquid stream to solids comprised largely of metal oxides.…”

“…The current baseline for the full separation option would include concentration and denitration of the LAW fraction to convert the liquid stream to solids comprised largely of metal oxides. The grout ingredients (Portland cement, slag, fly ash and water) would be mixed with the LAW solids, poured into drums, and allowed to cure [15]. This formulation allows for 30 wt % waste loading in the grout, which has a cured density of 1,826 kg/m 3 and a 28 day compressive strength of 1,600 psi [15].…”

“…The grout ingredients (Portland cement, slag, fly ash and water) would be mixed with the LAW solids, poured into drums, and allowed to cure [15]. This formulation allows for 30 wt % waste loading in the grout, which has a cured density of 1,826 kg/m 3 and a 28 day compressive strength of 1,600 psi [15]. Using this formulation, 0.21 L of grout is produced per liter of LAW [15].…”

“…This formulation allows for 30 wt % waste loading in the grout, which has a cured density of 1,826 kg/m 3 and a 28 day compressive strength of 1,600 psi [15]. Using this formulation, 0.21 L of grout is produced per liter of LAW [15]. Initial material balance calculations indicate there are approximately 5 L of LAW produced per liter of SBW treated in full separations.…”

Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-99 Status Report

“…Based on initial closure testing, tank heel displacement with grout and removal was determined favorable to direct heel grouting, with respect to both economics and waste form quality 10 . It was also determined during this initial testing that the heel solutions should be diluted with water to no more than 12.5% original solution to prevent excessive chemical degradation of the grout.…”