scholarly journals FIRE INVESTIGATION IN AN ITALIAN WASTE TREATMENT PLANT: LESSONS LEARNED AND FUTURE DEVELOPMENT

Author(s):  
GIOVANNI ROMANO ◽  
ALFREDO ROMANO
Author(s):  
T. Bond Calloway ◽  
Christopher J. Martino ◽  
Carol M. Jantzen ◽  
William R. Wilmarth ◽  
Michael E. Stone ◽  
...  

Evaporation of High Level and Low Activity (HLW & LAW) radioactive wastes for the purposes of radionuclide separation and volume reduction has been conducted at the Savannah River and Hanford Sites for more than forty years. Additionally, the Savannah River Site (SRS) has used evaporators in preparing HLW for immobilization into a borosilicate glass matrix. The Hanford River Protection Project (RPP) is in the process of building the world’s largest radioactive waste treatment facility, Waste Treatment Plant (WTP), which will use evaporators to concentrate the liquid waste and plant recycles prior to immobilization into a borosilicate glass matrix. Radioactive waste is evaporated at each site using various evaporator designs (e.g., forced circulation, horizontal bent tube). While the equipment used to evaporate radioactive waste is relatively simple in design, the complexity in the evaporator processes in current service and in those currently in the design stages stems from the heterogeneous nature of the waste and the effects of seemingly minor components (e.g., Si) on the process. Aqueous electrolyte thermodynamic modeling and experiments have been conducted by the SRS Savannah River Technology Center (SRTC) in support of the SRS HLW and Defense Waste Processing Facility (DWPF) Evaporators and the Hanford RPP WTP. After 40 years of successful operation, accumulation of two solid phases (a nitrated aluminosilicate, Na8AL6Si6O24(NO3)2•4H2O and sodium diuranate, Na2U2O7) developed as an insoluble phase in the Savannah River Site (SRS) 2H evaporator in 1996. The aluminosilicate scale deposit caused the SRS 2-H evaporator to become completely inoperable by October 1999. Accumulation of the sodium diuranate phase on the aluminosilicate scale has caused criticality concerns. Modeling and experiments were conducted to develop a method to control the process chemistry in order to prevent the formation of aluminosilicate deposits in the future. The lessons learned from the development, design, and operation of the SRS waste treatment facilities and the currently operating 242-A Hanford HLW evaporators were applied by SRTC in support of the development and design of the Hanford WTP evaporators. Thermodynamic equilibrium modeling along with solubility and physical property experiments are being conducted to develop process control and flow sheet models. Additionally, lessons learned from the development of an advanced antifoam agent for the SRS vitrification process evaporators are being applied to the testing and development of an antifoam agent for the Hanford WTP evaporators. This paper will discuss the methodologies, results, and achievements of the SRTC evaporator development program that was conducted in support of the SRS and Hanford WTP evaporator processes. The “cross-pollination” and application of waste treatment technologies and methods between the Savannah River and Hanford Sites will be highlighted. The “cross-pollination” of technologies and methods is expected to benefit the Department of Energy’s Mission Acceleration efforts by reducing the overall cost and time for the development of the baseline waste treatment processes.


2018 ◽  
Vol 2 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Tee L. Guidotti

On 16 October 1996, a malfunction at the Swan Hills Special Waste Treatment Center (SHSWTC) in Alberta, Canada, released an undetermined quantity of persistent organic pollutants (POPs) into the atmosphere, including polychlorinated biphenyls, dioxins, and furans. The circumstances of exposure are detailed in Part 1, Background and Policy Issues. An ecologically based, staged health risk assessment was conducted in two parts with two levels of government as sponsors. The first, called the Swan Hills Study, is described in Part 2. A subsequent evaluation, described here in Part 3, was undertaken by Health Canada and focused exclusively on Aboriginal residents in three communities living near the lake, downwind, and downstream of the SHSWTC of the area. It was designed to isolate effects on members living a more traditional Aboriginal lifestyle. Aboriginal communities place great cultural emphasis on access to traditional lands and derive both cultural and health benefits from “country foods” such as venison (deer meat) and local fish. The suspicion of contamination of traditional lands and the food supply made risk management exceptionally difficult in this situation. The conclusion of both the Swan Hills and Lesser Slave Lake studies was that although POPs had entered the ecosystem, no effect could be demonstrated on human exposure or health outcome attributable to the incident. However, the value of this case study is in the detail of the process, not the ultimate dimensions of risk. The findings of the Lesser Slave Lake Study have not been published previously and are incomplete.


1988 ◽  
Vol 20 (11-12) ◽  
pp. 131-136 ◽  
Author(s):  
A. D. Wong ◽  
C. D. Goldsmith

The effect of discharging specific oil degrading bacteria from a chemostat to a refinery activated sludge process was determined biokinetically. Plant data for the kinetic evaluation of the waste treatment plant was collected before and during treatment. During treatment, the 500 gallon chemostatic growth chamber was operated on an eight hour hydraulic retention time, at a neutral pH, and was fed a mixture of refinery wastewater and simple sugars. The biokinetic constants k (days−1), Ks (mg/L), and K (L/mg-day) were determined before and after treatment by Monod and Lineweaver-Burk plots. Solids discharged and effluent organic concentrations were also evaluated against the mean cell retention time (MCRT). The maximum utilization rate, k, was found to increase from 0.47 to 0.95 days−1 during the operation of the chemostat. Subsequently, Ks increased from 141 to 556 mg/L. Effluent solids were shown to increase slightly with treatment. However, this was acceptable due to the polishing pond and the benefit of increased ability to accept shock loads of oily wastewater. The reason for the increased suspended solids in the effluent was most likely due to the continual addition of bacteria in exponential growth that were capable of responding to excess substrate. The effect of the chemostatic addition of specific microbial inocula to the refinery waste treatment plant has been to improve the overall organic removal capacity along with subsequent gains in plant stability.


1994 ◽  
Vol 29 (8) ◽  
pp. 235-250 ◽  
Author(s):  
Norbert Amsoneit

As a rule, hazardous waste needs a pre-treatment, either a thermal or a chemical-physical one, before it can be disposed of at a landfill. The concentration of different kinds of treatment facilities at a Centralized Hazardous Waste Treatment Plant is advantageous. The facility of the ZVSMM at Schwabach is presented as an outstanding example of this kind of Treatment Centre. The infrastructure, the chemical-physical plant with separate lines for the treatment of organic and inorganic waste and the hazardous waste incinerator are described. Their functions are discussed in detail. Emphasis is laid on handling the residues produced by the different treatment processes and the final disposal.


2018 ◽  
Vol 171 ◽  
pp. 1006-1019 ◽  
Author(s):  
Esmeralda Neri ◽  
Fabrizio Passarini ◽  
Daniele Cespi ◽  
Federica Zoffoli ◽  
Ivano Vassura

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