Report on Toyota Prius Motor Thermal Management (open access)

Report on Toyota Prius Motor Thermal Management

In the current hybrid vehicle market, the Toyota Prius drive system is considered the leader in electrical, mechanical, and manufacturing innovations. It is a significant accomplishment that Toyota is able to manufacture and sell the vehicle for a profit. The Toyota Prius traction motor design approach for reducing manufacturing costs and the motor s torque capability have been studied and tested. The findings were presented in two previous Oak Ridge National Laboratory (ORNL) reports. The conclusions from this report reveal, through temperature rise tests, that the 2004 Toyota Prius (THSII) motor is applicable only for use in a hybrid automobile. It would be significantly undersized if used in a fuel cell vehicle application. The power rating of the Prius motor is limited by the permissible temperature rise of the motor winding (170 C) and the motor cooling oil (158 C). The continuous ratings at base speed (1200 rpm) with different coolant temperatures are projected from test data at 900 rpm. They are approximately 15 kW with 105 C coolant and 21 kW with 35 C coolant. These continuous ratings are much lower than the 30 kW specified as a technical motor target of the U.S. Department of Energy FreedomCAR Program. …
Date: February 11, 2005
Creator: Hsu, J.S.
Object Type: Report
System: The UNT Digital Library
Vision 21 Systems Analysis Methodologies Annual Report: 2001 (open access)

Vision 21 Systems Analysis Methodologies Annual Report: 2001

Under the sponsorship of the U.S. Department of Energy/National Energy Technology Laboratory, a multi-disciplinary team led by the Advanced Power and Energy Program of the University of California at Irvine is defining the system engineering issues associated with the integration of key components and subsystems into power plant systems that meet performance and emission goals of the Vision 21 program. The study efforts have narrowed down the myriad of fuel processing, power generation, and emission control technologies to selected scenarios that identify those combinations having the potential to achieve the Vision 21 program goals of high efficiency and minimized environmental impact while using fossil fuels. The technology levels considered are based on projected technical and manufacturing advances being made in industry and on advances identified in current and future government supported research. Included in these advanced systems are solid oxide fuel cells and advanced cycle gas turbines. The results of this investigation will serve as a guide for the U. S. Department of Energy in identifying the research areas and technologies that warrant further support.
Date: August 11, 2003
Creator: Samuelsen, G.S.; Rao, A.; Robson, F. & Washom, B.
Object Type: Report
System: The UNT Digital Library
Microstructural Evolution Based on Fundamental Interfacial Properties (open access)

Microstructural Evolution Based on Fundamental Interfacial Properties

This first CMSN project has been operating since the summer of 1999. The main achievement of the project was to bring together a community of materials scientists, physicists and mathematicians who share a common interest in the properties of interfaces and the impact of those properties on microstructural evolution. Six full workshops were held at Carnegie Mellon (CMU), Northwestern (NWU), Santa Fe, Northeastern University (NEU), National Institute for Standards and Technology (NIST), Ames Laboratory, and at the University of California in San Diego (UCSD) respectively. Substantial scientific results were obtained through the sustained contact between the members of the project. A recent issue of Interface Science (volume 10, issue 2/3, July 2002) was dedicated to the output of the project. The results include: the development of methods for extracting anisotropic boundary energy and mobility from molecular dynamics simulations of solid/liquid interfaces in nickel; the extraction of anisotropic energies and mobilities in aluminum from similar MD simulations; the application of parallel computation to the calculation of interfacial properties; the development of a method to extract interfacial properties from the fluctuations in interface position through consideration of interfacial stiffness; the use of anisotropic interface properties in studies of abnormal grain growth; the …
Date: July 11, 2003
Creator: Rollett, A. D.; Srolovitz, D. J. & Karma, A.
Object Type: Report
System: The UNT Digital Library
Initial Self-Consistent 3D Electron-Cloud Simulations of the LHC Beam with the Code WARP+POSINST (open access)

Initial Self-Consistent 3D Electron-Cloud Simulations of the LHC Beam with the Code WARP+POSINST

We present initial results for the self-consistent beam-cloud dynamics simulations for a sample LHC beam, using a newly developed set of modeling capability based on a merge [1] of the three-dimensional parallel Particle-In-Cell (PIC) accelerator code WARP [2] and the electron-cloud code POSINST [3]. Although the storage ring model we use as a test bed to contain the beam is much simpler and shorter than the LHC, its lattice elements are realistically modeled, as is the beam and the electron cloud dynamics. The simulated mechanisms for generation and absorption of the electrons at the walls are based on previously validated models available in POSINST [3, 4].
Date: October 11, 2005
Creator: Vay, J; Furman, M A; Cohen, R H; Friedman, A & Grote, D P
Object Type: Article
System: The UNT Digital Library
Hard x-ray imaging and spectroscopy of long pulse NIF hohlraums (open access)

Hard x-ray imaging and spectroscopy of long pulse NIF hohlraums

None
Date: October 11, 2005
Creator: McDonald, J. W.; Kauffman, R. L.; Suter, L. J.; Celeste, J. R.; Schneider, M. B.; Holder, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Summary of Travel Trends 2001 National Household Travel Survey (open access)

Summary of Travel Trends 2001 National Household Travel Survey

None
Date: January 11, 2005
Creator: Hu, PS
Object Type: Report
System: The UNT Digital Library
Physics of Low-Dimensional Bose-Einstein Condensates (open access)

Physics of Low-Dimensional Bose-Einstein Condensates

None
Date: December 11, 2008
Creator: Kolomeisky, Eugene B.
Object Type: Report
System: The UNT Digital Library
Investigation of Accelerated Casing Corrosion in Two Wells at Waste Management Area A-AX (open access)

Investigation of Accelerated Casing Corrosion in Two Wells at Waste Management Area A-AX

This report was revised in September 2008 to remove acid-extractable sodium data from Tables 3.13 and 3.14. The sodium data was removed due to potential contamination introduced during the acid extraction process. The rest of the text remains unchanged from the original report issued in August 2005. An overall goal of the Groundwater Performance Assessment Project, led by Pacific Northwest National Laboratory (PNNL) and per guidance in DOE Order 5400.1, includes characterizing and defining trends in the physical, chemical, and biological condition of the environment. To meet these goals, numerous Resource Conservation and Recovery Act (RCRA) monitoring wells have been installed throughout the Hanford Site. In 2003, it was determined that two RCRA monitoring wells (299-E24-19 and 299-E25-46) in Waste Management Area (WMA) A-AX failed due to rapid corrosion of the stainless steel casing over a significant length of the wells. Complete casing corrosion occurred between 276.6 and 277.7 feet below ground surface (bgs) in well 299- E24-19 and from 274.4 to 278.6 feet bgs in well 299-E25-46. CH2M HILL Hanford Group, Inc., asked scientists from PNNL to perform detailed analyses of vadose zone sediment samples collected in the vicinity of the WMA A-AX from depths comparable to those where …
Date: September 11, 2008
Creator: Brown, Christopher F.; Serne, R. Jeffrey; Schaef, Herbert T.; Williams, Bruce A.; Valenta, Michelle M.; Legore, Virginia L. et al.
Object Type: Report
System: The UNT Digital Library
ULAS J234311.93-005034.0: A Gravitational Lens System Selected from UKIDSSand SDSS (open access)

ULAS J234311.93-005034.0: A Gravitational Lens System Selected from UKIDSSand SDSS

None
Date: April 11, 2008
Creator: Jackson, Neal; Ofek, Eran O. & Oguri, Masamune
Object Type: Article
System: The UNT Digital Library
FRACTURE BEHAVIOR OF ALLOY 600, ALLOY 690, EN82H WELDS AND EN52 WELDS IN WATER (open access)

FRACTURE BEHAVIOR OF ALLOY 600, ALLOY 690, EN82H WELDS AND EN52 WELDS IN WATER

The cracking resistance of Alloy 600, Alloy 690 and their welds, EN82H and EN52, was characterized by conducting J{sub IC} rising load tests in air and hydrogenated water and cooldown testing in water under constant-displacement conditions. All test materials displayed excellent toughness in air and high temperature water, but Alloy 690 and the two welds were severely embrittled in low temperature water. In 54 C water with 150 cc H{sub 2}/kg H{sub 2}O, J{sub IC} values were reduced by 70% to 95%, relative to their air counterpart. The toughness degradation was associated with a fracture mechanism transition from microvoid coalescence to intergranular fracture. Comparison of the cracking response in water with that for hydrogen-precharged specimens tested in air demonstrated that susceptibility to low temperature crack propagation (LTCP) is due to hydrogen embrittlement of grain boundaries. The effects of water temperature, hydrogen content and loading rate on LTCP were studied. In addition, testing of specimens containing natural weld defects and as-machined notches was performed to determine if low temperature cracking can initiate at these features. Unlike the other materials, Alloy 600 is not susceptible to LTCP as the toughness in 54 C water remained high and a microvoid coalescence mechanism was …
Date: January 11, 2000
Creator: Mills, W.J., Brown, C.M. and Burke, M.G.
Object Type: Report
System: The UNT Digital Library
Enhanced Chemical Cleaning: A New Process for Chemically Cleaning Savannah River Waste Tanks (open access)

Enhanced Chemical Cleaning: A New Process for Chemically Cleaning Savannah River Waste Tanks

At the Savannah River Site (SRS) there are 49 High Level Waste (HLW) tanks that eventually must be emptied, cleaned, and closed. The current method of chemically cleaning SRS HLW tanks, commonly referred to as Bulk Oxalic Acid Cleaning (BOAC), requires about a half million liters (130,000 gallons) of 8 weight percent (wt%) oxalic acid to clean a single tank. During the cleaning, the oxalic acid acts as the solvent to digest sludge solids and insoluble salt solids, such that they can be suspended and pumped out of the tank. Because of the volume and concentration of acid used, a significant quantity of oxalate is added to the HLW process. This added oxalate significantly impacts downstream processing. In addition to the oxalate, the volume of liquid added competes for the limited available tank space. A search, therefore, was initiated for a new cleaning process. Using TRIZ (Teoriya Resheniya Izobretatelskikh Zadatch or roughly translated as the Theory of Inventive Problem Solving), Chemical Oxidation Reduction Decontamination with Ultraviolet Light (CORD-UV{reg_sign}), a mature technology used in the commercial nuclear power industry was identified as an alternate technology. Similar to BOAC, CORD-UV{reg_sign} also uses oxalic acid as the solvent to dissolve the metal (hydr)oxide …
Date: February 11, 2009
Creator: Ketusky, Edward; Spires, Renee & Davis, Neil
Object Type: Article
System: The UNT Digital Library
Search For the Highly Suppressed Decays B- -> K+ pi- pi- and B- -> K- K- pi+ (open access)

Search For the Highly Suppressed Decays B- -> K+ pi- pi- and B- -> K- K- pi+

The authors report a search for the decays B{sup -} {yields} K{sup +}{pi}{sup -}{pi}{sup -} and B{sup -} {yields} K{sup -}K{sup -}{pi}{sup +}, which are highly suppressed in the Standard Model. Using a sample of (467 {+-} 5) x 10{sup 6} B{bar B} pairs collected with the BABAR detector, they do not see any evidence of these decays and determine 90% confidence level upper limits of {Beta}(B{sup -} {yields} K{sup +}{pi}{sup -}{pi}{sup -}) < 9.5 x 10{sup -7} and {Beta}(B{sup -} {yields} K{sup -}K{sup -}{pi}{sup +}) < 1.6 x 10{sup -7} on the corresponding branching fractions, including systematic uncertainties.
Date: August 11, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
EFFECTS OF OXYGEN AND AIR MIXING ON VOID FRACTIONS IN A LARGE SCALE SYSTEM (open access)

EFFECTS OF OXYGEN AND AIR MIXING ON VOID FRACTIONS IN A LARGE SCALE SYSTEM

Oxygen and air mixing with spargers was performed in a 30 foot tall by 30 inch diameter column, to investigate mass transfer as air sparged up through the column and removed saturated oxygen from solution. The mixing techniques required to support this research are the focus of this paper. The fluids tested included water, water with an antifoam agent (AFA), and a high, solids content, Bingham plastic, nuclear waste simulant with AFA, referred to as AZ01 simulant, which is non-radioactive. Mixing of fluids in the column was performed using a recirculation system and an air sparger. The re-circulation system consisted of the column, a re-circulating pump, and associated piping. The air sparger was fabricated from a two inch diameter pipe concentrically installed in the column and open near the bottom of the column. The column contents were slowly re-circulated while fluids were mixed with the air sparger. Samples were rheologically tested to ensure effective mixing, as required. Once the fluids were adequately mixed, oxygen was homogeneously added through the re-circulation loop using a sintered metal oxygen sparger followed by a static mixer. Then the air sparger was re-actuated to remove oxygen from solution as air bubbled up through solution. To …
Date: September 11, 2008
Creator: Leishear, R; Hector Guerrero, H & Michael Restivo, M
Object Type: Article
System: The UNT Digital Library
Qualification of Automated Low-Field NMR Relaxometry for Quality Control of Polymers in a Production Setting (open access)

Qualification of Automated Low-Field NMR Relaxometry for Quality Control of Polymers in a Production Setting

Implementation of a low field time-domain NMR scanner as a diagnostic tool in the production of new polymer components is described in the context of qualification of a new QA/QC device. A study to determine the optimal experimental parameters was performed and a robotic autosampler was built to enable scanning of multiple pads. Relationships between T{sub 2} values and physical properties of DC745 slabs were investigated, and the appropriate sampling parameters for the production setting were determined. Two versions of a robotic autosampler were built, and for the component described here a fourth radial axis was required in addition to traditional X, Y, and Z movement to eliminate the large variability in T{sub 2} due to inconsistent sample coverage caused by complex rib geometry of the component. Data show that with appropriate choice of experimental conditions of the NMR detector and the detection geometry of the robotic autosampler, sufficient resolution of variations in crosslink density on the millimeter scale could be determined. All data to date demonstrates that low-field NMR devices are a feasible tool for use in production settings for non-destructive quality control of polymer components.
Date: May 11, 2007
Creator: Chinn, S; Cook-Tendulkar, A; Maxwell, R; Wheeler, H; Wilson, M & Xie, Z
Object Type: Article
System: The UNT Digital Library
Residual stress measurement and microstructural characterization of thick beryllium films (open access)

Residual stress measurement and microstructural characterization of thick beryllium films

Beryllium films are synthesized by a magnetron sputtering technique incorporating in-situ residual stress measurement. Monitoring the stress evolution in real time provides quantitative through-thickness information on the effects of various processing parameters, including sputtering gas pressure and substrate biasing. Specimens produced over a wide range of stress states are characterized via transmission and scanning electron microscopy, and atomic force microscopy, in order to correlate the stress data with microstructure. A columnar grain structure is observed for all specimens, and surface morphology is found to be strongly dependent on processing conditions. Analytical models of stress generation are reviewed and discussed in terms of the observed microstructure.
Date: February 11, 2008
Creator: Detor, A.; Wang, M.; Hodge, A. M.; Chason, E.; Walton, C.; Hamza, A. V. et al.
Object Type: Report
System: The UNT Digital Library
Sludge Batch 5 Slurry Fed Melt Rate Furnace Test with Frits 418 and 550 (open access)

Sludge Batch 5 Slurry Fed Melt Rate Furnace Test with Frits 418 and 550

Based on Melt Rate Furnace (MRF) testing for the Sludge Batch 5 (SB5) projected composition and assessments of the potential frits with reasonable operating windows, the Savannah River National Laboratory (SRNL) recommended Slurry Fed Melt Rate Furnace (SMRF) testing with Frits 418 and 550. DWPF is currently using Frit 418 with SB5 based on SRNL's recommendation due to its ability to accommodate significant sodium variation in the sludge composition. However, experience with high boron containing frits in DWPF indicated a potential advantage for Frit 550 might exist. Therefore, SRNL performed SMRF testing to assess Frit 550's potential advantages. The results of SMRF testing with SB5 simulant indicate that there is no appreciable difference in melt rate between Frit 418 and Frit 550 at a targeted 34 weight % waste loading. Both batches exhibited comparable behavior when delivered through the feed tube by the peristaltic pump. Limited observation of the cold cap during both runs showed no indication of major cold cap mounding. MRF testing, performed after the SMRF runs due to time constraints, with the same two Slurry Mix Evaporator (SME) dried products led to the same conclusion. Although visual observations of the cross-sectioned MRF beakers indicated differences in the …
Date: February 11, 2009
Creator: Miller, Donald & Pickenheim, Bradley
Object Type: Report
System: The UNT Digital Library
Melting of Transition Metals (open access)

Melting of Transition Metals

We review the transition melting studies carried out at Mainz, and describe a recently developed model used to explain that the relatively low melting slopes are due to the partially filled d-bands, and the persistence of the pressure induced s-d transition. The basic tenets of the model have now been reconfirmed by new measurements for Cu and Ni. The measurements show that Cu which has a filled 3d-band, has a melt slope that is about 2.5 greater than its neighbor Ni. In the case of Mo, the apparent discrepancy of DAC melting measurements with shock melting can be explained by accounting for the change in melt slope due to the bcc-cp transition observed in the shock studies. The Fe melt curve is revisited. The possible relevance of the Jahn-Teller effect and recently observed transition metal melts with Icosahedral Short-Range Order (ISRO) is discussed.
Date: April 11, 2005
Creator: Ross, M; Japel, S & Boehler, R
Object Type: Article
System: The UNT Digital Library
Reactor Physics and Criticality Benchmark Evaluations for Advanced Nuclear Fuel - Final Technical Report (open access)

Reactor Physics and Criticality Benchmark Evaluations for Advanced Nuclear Fuel - Final Technical Report

The nuclear industry interest in advanced fuel and reactor design often drives towards fuel with uranium enrichments greater than 5 wt% 235U. Unfortunately, little data exists, in the form of reactor physics and criticality benchmarks, for uranium enrichments ranging between 5 and 10 wt% 235U. The primary purpose of this project is to provide benchmarks for fuel similar to what may be required for advanced light water reactors (LWRs). These experiments will ultimately provide additional information for application to the criticality-safety bases for commercial fuel facilities handling greater than 5 wt% 235U fuel.
Date: September 11, 2008
Creator: Anderson, William; Tulenko, James; Rearden, Bradley & Harms, Gary
Object Type: Report
System: The UNT Digital Library
Three-dimensional analysis of free-electron laser performance using brightness scaled variables (open access)

Three-dimensional analysis of free-electron laser performance using brightness scaled variables

A three-dimensional analysis of radiation generation in a free-electron laser (FEL) is performed in the small signal regime. The analysis includes beam conditioning, harmonic generation, flat beams, and a new scaling of the FEL equations using the six-dimensional beam brightness. The six-dimensional beam brightness is an invariant under Liouvillian flow; therefore, any nondissipative manipulation of the phase-space, performed, for example, in order to optimize FEL performance, must conserve this brightness. This scaling is more natural than the commonly-used scaling with the one-dimensional growth rate. The brightness-scaled equations allow for the succinct characterization of the optimal FEL performance under various additional constraints. The analysis allows for the simple evaluation of gain enhancement schemes based on beam phase space manipulations such as emittance exchange and conditioning. An example comparing the gain in the first and third harmonics of round or flat and conditioned or unconditioned beams is presented.
Date: June 11, 2008
Creator: Penn, Gregory; Gullans, M.; Penn, G.; Wurtele, J.S. & Zolotorev, M.
Object Type: Article
System: The UNT Digital Library
Linear scaling 3D fragment method for large-scale electronic structure calculations (open access)

Linear scaling 3D fragment method for large-scale electronic structure calculations

We present a new linearly scaling three-dimensional fragment (LS3DF) method for large scale ab initio electronic structure calculations. LS3DF is based on a divide-and-conquer approach, which incorporates a novel patching scheme that effectively cancels out the artificial boundary effects due to the subdivision of the system. As a consequence, the LS3DF program yields essentially the same results as direct density functional theory (DFT) calculations. The fragments of the LS3DF algorithm can be calculated separately with different groups of processors. This leads to almost perfect parallelization on tens of thousands of processors. After code optimization, we were able to achieve 35.1 Tflop/s, which is 39% of the theoretical speed on 17,280 Cray XT4 processor cores. Our 13,824-atom ZnTeO alloy calculation runs 400 times faster than a direct DFT calculation, even presuming that the direct DFT calculation can scale well up to 17,280 processor cores. These results demonstrate the applicability of the LS3DF method to material simulations, the advantage of using linearly scaling algorithms over conventional O(N{sup 3}) methods, and the potential for petascale computation using the LS3DF method.
Date: July 11, 2008
Creator: Wang, Lin-Wang; Wang, Lin-Wang; Lee, Byounghak; Shan, HongZhang; Zhao, Zhengji; Meza, Juan et al.
Object Type: Article
System: The UNT Digital Library
Rapid, Absolute Calibration of X-ray Filters Employed By Laser-Produced Plasma Diagnostics (open access)

Rapid, Absolute Calibration of X-ray Filters Employed By Laser-Produced Plasma Diagnostics

The electron beam ion trap (EBIT) facility at the Lawrence Livermore National Laboratory is being used to absolutely calibrate the transmission efficiency of X-ray filters employed by diodes and spectrometers used to diagnose laser-produced plasmas. EBIT emits strong, discrete monoenergetic lines at appropriately chosen X-ray energies. X-rays are detected using the high-resolution EBIT calorimeter spectrometer (ECS), developed for LLNL at the NASA/Goddard Space Flight Center. X-ray filter transmission efficiency is determined by dividing the X-ray counts detected when the filter is in the line of sight by those detected when out of the line of sight. Verification of filter thickness can be completed in only a few hours, and absolute efficiencies can be calibrated in a single day over a broad range from about 0.1 to 15 keV. The EBIT calibration lab has been used to field diagnostics (e.g., the OZSPEC instrument) with fully calibrated X-ray filters at the OMEGA laser. Extensions to use the capability for calibrating filter transmission for the DANTE instrument on the National Ignition Facility are discussed.
Date: May 11, 2008
Creator: Brown, G. V.; Beiersdorfer, P.; Emig, J.; Frankel, M.; Gu, M. F.; Heeter, R. F. et al.
Object Type: Article
System: The UNT Digital Library
Deformation Microstructures and Creep Mechanisms in Advanced ZR-Based Cladding Under Biazal Loading (open access)

Deformation Microstructures and Creep Mechanisms in Advanced ZR-Based Cladding Under Biazal Loading

Investigate creep behavior of Zr-based cladding tubes with attention to basic creep mechanisms and transitions in them at low stresses and/or temperatures and study the dislocation microstructures of deformed samples for correlation with the underlying micromechanism of creep
Date: August 11, 2008
Creator: Murty, K. Linga (KL)
Object Type: Report
System: The UNT Digital Library
Massively Parallel QCD (open access)

Massively Parallel QCD

The theory of the strong nuclear force, Quantum Chromodynamics (QCD), can be numerically simulated from first principles on massively-parallel supercomputers using the method of Lattice Gauge Theory. We describe the special programming requirements of lattice QCD (LQCD) as well as the optimal supercomputer hardware architectures that it suggests. We demonstrate these methods on the BlueGene massively-parallel supercomputer and argue that LQCD and the BlueGene architecture are a natural match. This can be traced to the simple fact that LQCD is a regular lattice discretization of space into lattice sites while the BlueGene supercomputer is a discretization of space into compute nodes, and that both are constrained by requirements of locality. This simple relation is both technologically important and theoretically intriguing. The main result of this paper is the speedup of LQCD using up to 131,072 CPUs on the largest BlueGene/L supercomputer. The speedup is perfect with sustained performance of about 20% of peak. This corresponds to a maximum of 70.5 sustained TFlop/s. At these speeds LQCD and BlueGene are poised to produce the next generation of strong interaction physics theoretical results.
Date: April 11, 2007
Creator: Soltz, R.; Vranas, P.; Blumrich, M.; Chen, D.; Gara, A.; Giampap, M. et al.
Object Type: Article
System: The UNT Digital Library
EFFECTIVENESS OF USING DILUTE OXALIC ACID TO DISSOLVEHIGH LEVEL WASTE IRON BASED SLUDGE SIMULANT (open access)

EFFECTIVENESS OF USING DILUTE OXALIC ACID TO DISSOLVEHIGH LEVEL WASTE IRON BASED SLUDGE SIMULANT

At the Savannah River Site (SRS), near Aiken South Carolina, there is a crucial need to remove residual quantities of highly radioactive iron-based sludge from large select underground storage tanks (e.g., 19,000 liters of sludge per tank), in order to support tank closure. The use of oxalic acid is planned to dissolve the residual sludge, hence, helping in the removal. Based on rigorous testing, primarily using 4 and 8 wt% oxalic acid solutions, it was concluded that the more concentrated the acid, the greater the amount of residual sludge that would be dissolved; hence, a baseline technology on using 8 wt% oxalic acid was developed. In stark contrast to the baseline technology, reports from other industries suggest that the dissolution will most effectively occur at 1 wt% oxalic acid (i.e., maintaining the pH near 2). The driver for using less oxalic acid is that less (i.e., moles) would decrease the severity of the downstream impacts (i.e., required oxalate solids removal efforts). To determine the initial feasibility of using 1 wt% acid to dissolve > 90% of the sludge solids, about 19,000 liters of representative sludge was modeled using about 530,000 liters of 0 to 8 wt% oxalic acid solutions. With …
Date: July 11, 2008
Creator: Ketusky, E
Object Type: Article
System: The UNT Digital Library