Dr Robert Gerritse by hjkuiw354

VIEWS: 30 PAGES: 5

									       Phosphate Clay Liners CO2 Mobility Diffusion Soils Coral Bay Polack Böhme


  Calculator for estimating travel times of phosphate: click here


  Abstracts of recent papers & drafts:
Gerritse R.G. and Thomas G.A. (2008).
Transport of bauxite residue leachate through clay liners of storage
impoundments: a synthesis of experimental and simulated data. In
Proceedings 8th International Alumina Quality Workshop, Darwin, 7-
12 September, 2008.
Abstract
Although many alumina refineries use bores situated around their residue areas to monitor the
integrity of the storage liners there has been little detailed work on the effects of alkaline liquor
from bauxite residue on the clay liners of storage impoundments. At high temperatures, alkaline
fluids have been shown to rapidly react with bentonite clays, resulting in dissolution of bentonite
after formation of calcium silicate hydrate and calcium-aluminium silicate hydrate mineral
phases. Reaction rates decrease exponentially with decreasing temperature and become very low
at pH<10.5. Modelling suggests that alkaline dissolution and subsequent precipitation of minerals
are likely to occur in approximately similar quantities. These reactions, though
initially decreasing permeability, may ultimately lead to a degradation of the clay structure and
thus an increase in permeability.
The objective of this work was to predict the life times of existing clay liners from detailed
analysis of the integrity of cores collected from a reside storage area. Four cores sampled from a
clay liner of a storage impoundment at Alcoa’s Kwinana Alumina Refinery were examined. The
clay liner had been exposed, at the time of sampling, to bauxite residue for periods of 20-23
years.
Profile distributions in the cores of alkalinity, Na, Cl and Br were measured and compared with
results obtained by numerically simulating the transport of Na. Linear extrapolation in time of
profile distributions of alkalinity and Na suggests times for breakthrough of leachate through the
clay liner may be of the order of 30 to 70 years in the absence of hydraulic head reduction. A
considerable amount of alkalinity, however, is removed from solution after reaction with clay
minerals and is not readily exchangeable. The ‘on-going’ reaction of alkaline residue leachate
with clay progressively slows its movement in a non-linear fashion. Resulting ‘breakthrough
times’ of residue leachate through clay liners are thus likely to be greater than estimated from a
linear extrapolation in time of the profile distributions in cores. Based on the knowledge obtained
from this work, Alcoa has developed methods for reduction of hydraulic heads in residue areas
where breakthrough may be a risk.
Over the last decade, Alcoa has also taken several steps to enhance containment of residue
leachate in new residue facilities, including the use of geomembrane-clay composite seals and the
newly developed Carbon Capture process which significantly lowers the pH of residue leachate.




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CO2 diffusion in alkaline contaminated soils (Gerritse, in Prep.)
Introduction

     Spills of caustic process fluids from pipelines and storage tanks on to soils at alumina
refineries commonly leach down rapidly to groundwater and result in elevated concentrations of
Na in groundwater with pHs ranging up to 11. Initial pHs in process fluids can vary between 11
and 14, depending on the nature and source of the spill. Once in the soil, high pHs of the soil
solution can effectively be buffered to pHs of about 9 to 10 through diffusion of CO2 from the
atmosphere into the vadose zone and even lower when additional CO2 is generated in soil through
microbial processes. Equilibration with atmospheric CO2 can thus significantly reduce the pH of
soils affected by caustic process liquors.
For conservative behaviour of NaOH from process fluids in the vadose zone, rapid leaching to
groundwater with recharge from rainfall would be expected. However, even several years after a
caustic spill, pHs of the soil solution can still range up to 14. The persistent alkaline nature of
soils affected by caustic process fluids suggests formation of alkaline reaction products, which are
not readily leached.
Concentrations of Al and Si in extracts of soils with caustic soda are invariably found to be less
than expected for equilibrium with aluminosilicates. Calculations with ‘Phreeqc’ confirm this
and indicate that various hydrated Ca-aluminates can form at high pH, such as Ca4Al2O7.19H2O
and tricalcium alumina hydrates (TCA: such as katoite: Ca3Al2(SiO4)3-x(OH)4x (x=1.5-3)).
Possibly more important at high concentrations of NaOH is the formation of ‘desilication
products’, which are aluminosilicates with a high content of Na and relatively low content of Si,
such as zeolites, sodalite (Na4Al3(SiO4)3Cl) and cancrinite (Na7CaAl6Si6O24(CO3)2). A
considerable amount of alkalinity is absorbed in these ‘minerals’ and is only slowly dissolved,
when extracting with water. Caustic contamination remaining in the vadose zone, apparently
equilibrates very slowly with CO2.
Diffusion of CO2 from the atmosphere into caustic soils is simulated for equilibration with the
soil solution. Partition of CO2 between gas and liquid phases in a soil is calculated with a
hydrochemical simulation program. In this way a lower estimate of diffusion times of CO2 in
soils is obtained. Simulated diffusion times are compared with actual distributions of CO2
pressures in soil profiles affected by spills of caustic process liquors. Actual diffusion times
estimated from these profile distributions will be greater through adsorption of CO2 to caustic soil
materials, resulting from reactions with NaOH.

Aspects of transport of phosphate in soils, illustrated with a
spreadsheet-based numerical model (Unpubl.)
Abstract

    Transport of phosphate in a soil was modelled numerically with an Excel® spreadsheet. The
spreadsheet model simulates advective and diffusive transport of phosphate in a soil and includes
a ‘sink’ term, approximating the ongoing slow reaction of phosphate with soil materials. Input
parameters are based on a Freundlich type adsorption equation, fitted to data from batch soil
adsorption experiments. Outputs of the spreadsheet model were consistent with breakthrough
curves of step increases of phosphate, leached through small columns of soil. Outputs were
stabile for relatively high rates of flow and short distances of migration and validated an
empirical equation for calculating travel times, proposed previously. Click for Full Paper


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                                                            Coral Bay Groundwater


   Chemical analysis data for artesian groundwater from about 1 km
   depth, sampled at Coral Bay (Western Australia) and for spring
   water from the Darling Range in the SW of Western Australia:

                                                Coral Bay          Darling Range
Source
                                           Artesian groundwater Origin mineral water
Date of sampling                                29/10/2008          29/10/2008
pH                          pH-lab     -             7.4                 7.2
Conductivity at 25C         EC-lab    mS/m          830                   29
Alkalinity as CaCO3          ALK      mg/L          300                   16
TOC                          TOC      mg/L           <1                   <1
Sodium - Filterable           Na      mg/L         1775                   45
Potassium - Filterable         K      mg/L           30                    1
Magnesium filtered            Mg      mg/L           19                    5
Calcium filtered              Ca      mg/L           78                   1.7
Chloride                       Cl     mg/L         2140                   64
Bromide                        Br     mg/L           7.7                0.43
Fluoride                       F      mg/L           1.6               <0.05
Sulfate as SO4-S            S-SO4     mg/L          253                  4.2
Silicon filtered             Si-tot   mg/L           12                   5.5
Silica as SiO2              Si-SiO2   mg/L          14.5                 6.1
Boron filtered                 B      mg/L           3.3                 0.03
Nitrate as NO3-N (Calc)     N-NO3     mg/L         <0.01                 0.8
Total Nitrogen - Filterable N-tot     mg/L          6.3                 0.94
ortho-Phosphate as PO4-P P-PO4        mg/L         0.005               <0.005
Iron filtered                  Fe     mg/L          0.01               <0.005
Manganese filtered            Mn      mg/L          0.06                0.016
Molybdenum filtered           Mo      mg/L        <0.001               <0.001
Arsenic filtered              As      mg/L        <0.001               <0.001
Mercury filtered              Hg      mg/L        <0.0001             <0.0001
Selenium filtered              Se     mg/L        <0.001               <0.001
Uranium filtered               U      mg/L        <0.001               <0.001
Cadmium filtered              Cd      mg/L        <0.0001             <0.0001
Copper filtered               Cu      mg/L        <0.001                 0.01
Lead filtered                  Pb     mg/L        <0.001               <0.001
Thorium-Filtered              Th      mg/L        <0.001               <0.001
Zinc filtered                 Zn      mg/L         0.016                0.015




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                                                                                  Robert Polack Illustrator
     (things totally unrelated!)




                                                                          Robert Polack was a superb illustrator of
                                                                          books and designer of art-deco posters in the
                                                                          1920’s and 1930’s, well known in Paris and
                                                                          New-York.




Examples:
POLACK, Robert. PUBLICITES [title on binding]. A collection of superb art deco announcements, invitations and
advertising cards for openings of new fashion collections of chic Paris clothing and accessories shown in the finest
shops, mostly in Paris and New York, but also in Chicago, Philadelphia and Montreal. The collection consists of 22
cards, most folding and colored by pochoir with fine art deco era typography. All are printed in Paris by Georges
Gotscho and all are by Robert Polack. Some are dated, most 1925 or 1926; one is dated as early as 1916 and one is a
New Year’s greeting for 1927. These cards display a variety of spectacular art deco designs – fashion, typography and
pochoir illustration. Among the shops represented are Rappaport & Gottlieb, Claire, Mary Porpora and Fashion
Biltgown from New York; Yvonne Raynaud and Henry from Paris; Chas. A. Stevens of Chicago; and Janet Cooper in
London. Very rare; a unique collection housed in an attractive modern chemise and slipcase resembling one of the
period.
Musset, Alfred de. - La confession d'un enfant du siècle / Alfred de Musset ; [aquarelles de Robert-Polack]. - Paris :
Editions Nilsson, [1930]. - 268 p., 6 f. de pl. : ill. ; 24 cm. - (Collection Lotus). - 6 planches hors texte et couverture en
couleurs sur papier de soie (pochoir et retouches à la main sur canevas gravé?).
Musset, Alfred de. Ses Plus Beauz Vers. 280 pp. Illus. with 6 tipped-in pochoir plates by Robert Polack on parchment-
like paper. 9-1/4x6-3/4, thin parchment wrappers over thicker plain wrappers, with pochoir illustrations on front & rear.
Paris: Nilsson, c.1930's. Stan Laurel's copy, with the comedian's rubberstamp "Property of Stan Laurel" on the inside of
front & rear wrappers and on the front fly leaf. A beautifully illustrated work with softly erotic pochoir plates. Chipping
to wrappers, some internal darkening, else very good. (200/300).




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                                                             Hans Böhme Painter




                                                 Hans Böhme (1905-1982) was a prolific
                                                 painter of scenes around the river
                                                 Tauber (G). He lived in Rothenburg.




Biography:
Hans Böhme (1905-1982).
WWII war artist ?????? Further info sought




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