Fixation of Leachable Elements in Composite Waste Forms from North Dakota Lignite Coal Conversion Ash

1987 ◽  
Vol 113 ◽  
Author(s):  
D. J. Hasseti ◽  
D. F. Hassett
Keyword(s):  
North Dakota ◽  
Coal Gasification ◽  
Tap Water ◽  
Liquid Waste ◽  
Waste Incinerator ◽  
Leaching Tests ◽  
Waste Streams ◽  
Ettringite Formation ◽  
Batch Tests ◽  
Waste Forms

ABSTRACTComposite waste forms prepared using solid and liquid waste streams from an integrated coal gasification facility at Beulah, North Dakota, were evaluated for the potential leachability of select trace elements using batch tests. Cylinders were fabricated from seven blends of the solid components using liquid waste incinerator blowdown, multi-effect evaporator concentrate, or tap water. Individual waste forms and composites were leached using the same protocols. Both long term and short term leaching tests were used to evaluate these composite waste forms.Comparisons of measured concentrations of elements with values calculated from data on individual components were used to determine any change in leachability that may have occurred. These changes were expressed as a fixation factor, which is a term derived by dividing the calculated leachability by the measured concentrations from the actual leaching tests. Results from these experiments indicated that leachability of some elements could be lowered by the mixing of various solid and liquid waste streams. Ettringite formation is one possible mechanism responsible for fixation of several of the elements.

PHREEQC Modelling of Leaching of Major Elements and Heavy Metals From Cementitious Waste Forms

2008 ◽  
Vol 1107 ◽  
Author(s):  
Evelien Martens ◽  
Diederik Jacques ◽  
Tom Van Gerven ◽  
Lian Wang ◽  
Dirk Mallants
Keyword(s):  
Solid Solutions ◽  
Bottom Ash ◽  
Major Elements ◽  
Cementitious Material ◽  
Waste Incinerator ◽  
Waste Forms ◽  
Phreeqc Modelling ◽  
Single Set ◽  
Good Agreement ◽  
Mineralogical Phases

AbstractIn this study, Ca, Mg, Al, and Pb concentrations leached from uncarbonated and carbonated ordinary Portland cement – dried waste incinerator bottom ash samples during single extraction tests (EN12457 test) at a pH from 1 to 12, were modelled using the geochemical code PHREEQC. A good agreement was found between modelling results and experiments in terms of leached concentrations for Ca, Mg, and Al by defining a single set of pure mineralogical phases for both the uncarbonated and carbonated (three levels) samples. The model also predicted well the observed decrease in Ca leaching with increasing carbonation. Modelling results further revealed that leaching of Pb is not controlled by dissolution/precipitation of pure Pb containing minerals only (carbonates and (hydr)oxides). The addition of solid solutions (calcite-cerrusite and gibbsite-ferrihydrite-litharge solid solutions) and adsorption reactions on amorphous Fe- and Al-oxides improved the model representation of the experimentally observed amphoteric leaching profile of Pb from the cementitious material.

A Comparison of the Performance of Nuclear Waste Glasses by Modeling

1987 ◽  
Vol 112 ◽  
Author(s):  
B. Grambow ◽  
D. M. Strachan
Keyword(s):  
Nuclear Waste ◽  
Nuclear Reactors ◽  
Liquid Waste ◽  
Spent Fuel ◽  
High Level Liquid Waste ◽  
Geologic Repository ◽  
Waste Forms ◽  
The Earth ◽  
Soluble Solid ◽  
High Level

The reprocessing of spent fuel from nuclear reactors and processing of fuels for defense purposes have generated large volumes of high-level liquid waste that need to be immobilized prior to final storage. For immobilization, the wastes must be converted to a less soluble solid, and, although other waste forms exist, glass currently appears to be the choice for the transuranic-containing portion of the reprocessed waste. Once produced, this glass will be sent in canisters to a geologic repository located some 200 to 500 m below the surface of the earth.

Leaching Scale Effect for Cement-Waste Forms

1988 ◽  
Vol 127 ◽  
Author(s):  
J. C. Nomine ◽  
A. Billon ◽  
G. Courtois
Keyword(s):  
Scale Effect ◽  
Practical Method ◽  
Full Scale ◽  
Time Limit ◽  
Waste Form ◽  
Leaching Tests ◽  
Local Policy ◽  
Waste Package ◽  
Waste Forms

The confinement ability of a waste package is one of the major safety characteristics to consider in shallow land burial. In order to determine if the confinement is acceptable, in accordance with local policy, one way is to proceed to leaching tests. The practical method, for sake of simplicity, cost and time limit, is to carry out the leaching tests on laboratory samples which are easier to prepare than full-scale blocks, but the representativity of which needs to be treated with caution; it is in this context, that one of the aspect of our work concerns what is known as the “scale effect”.This study has been conducted using blocks the volumes of which are respectively of 200, 20, 2 and 0, 2 1, and made with the same cement-waste form (13 Cs) system.

scholarly journals Apatite- and Monazite-Bearing Glass-Crystal Composites for the Immobilization of Low-Level Nuclear and Hazardous Wastes

1995 ◽  
Vol 412 ◽  
Author(s):  
D. J. Wronkiewicz ◽  
S. F. Wolf ◽  
T. S. DiSanto
Keyword(s):  
Transition Metals ◽  
Nuclear Waste ◽  
Toxic Metals ◽  
Hazardous Wastes ◽  
Waste Streams ◽  
Waste Forms ◽  
Glass Crystal ◽  
High Level Nuclear Waste ◽  
High Level ◽  
Crystal Composite

AbstractThis study demonstrates that glass-crystal composite waste forms can be produced from waste streams containing high proportions of phosphorus, transition metals, and/or halides. The crystalline phases produced in crucible-scale melts include apatite, monazite, spinels, and a Zr-Si-Fe-Ti phase. These phases readily incorporated radionuclide and toxic metals into their crystal structures, while corrosion tests have demonstrated that glass-crystal composites can be up to 300-fold more durable than simulated high-level nuclear waste glasses, such as SRL 202U.

Investigation of the feasibility of underground coal gasification in North Dakota, United States

2016 ◽  
Vol 113 ◽  
pp. 95-103 ◽  
Author(s):  
Peng Pei ◽  
Junior Nasah ◽  
Jaroslav Solc ◽  
Scott F. Korom ◽  
Daniel Laudal ◽  
...  
Keyword(s):  
United States ◽  
North Dakota ◽  
Coal Gasification ◽  
Underground Coal Gasification

Algae biomass cultivation in nitrogen rich biogas digestate

2015 ◽  
Vol 72 (10) ◽  
pp. 1723-1729 ◽  
Author(s):  
I. Krustok ◽  
J. G. Diaz ◽  
M. Odlare ◽  
E. Nehrenheim
Keyword(s):  
Wastewater Treatment ◽  
Liquid Waste ◽  
Algal Growth ◽  
Significant Inhibition ◽  
Ammonium Concentration ◽  
Biomass Growth ◽  
Waste Streams ◽  
Algae Biomass ◽  
Biogas Digestate ◽  
Ammonium Tolerance

Because microalgae are known for quick biomass growth and nutrient uptake, there has been much interest in their use in research on wastewater treatment methods. While many studies have concentrated on the algal treatment of wastewaters with low to medium ammonium concentrations, there are several liquid waste streams with high ammonium concentrations that microalgae could potentially treat. The aim of this paper was to test ammonium tolerance of the indigenous algae community of Lake Mälaren and to use this mixed consortia of algae to remove nutrients from biogas digestate. Algae from Lake Mälaren were cultivated in Jaworski's Medium containing a range of ammonium concentrations and the resulting algal growth was determined. The algae were able to grow at NH4-N concentrations of up to 200 mg L−1 after which there was significant inhibition. To test the effectiveness of the lake water algae on the treatment of biogas digestate, different pre-cultivation set-ups and biogas digestate concentrations were tested. It was determined that mixing pre-cultivated suspension algae with 25% of biogas digestate by volume, resulting in an ammonium concentration of around 300 mg L−1, produced the highest algal growth. The algae were effective in removing 72.8 ± 2.2% of NH4-N and 41.4 ± 41.4% of PO4-P.

scholarly journals Formulation and Analysis of Compliant Grouted Waste Forms for SHINE Waste Streams

2014 ◽  
Author(s):  
William Ebert ◽  
Candido Pereira ◽  
Thad A. Heltemes ◽  
Amanda Youker ◽  
Vakhtang Makarashvili ◽  
...  
Keyword(s):  
Waste Streams ◽  
Waste Forms
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