Hydrochemistry and energy storage in aquifers - NHV.nu

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vary more than Gapon coefficients (Beekman and Appelo, 1988b) as the Na exchange fraction varied from 0 to 0.25. Additionally, the selectivity coefficient for Ca decreases relative to that of Mg as exchangeable Na increases (Sposito and LeVesque, 1985; Beekman and Appelo, 1988a,b). Using the classical field injection data set of Valocchi et al. (1981), C.A.J. Appelo (manuscript in preparation) has evaluated the commonly used Gapon, Gaines-Thomas, and the Vanselow equations and concluded that the latter two give more satisfactory results than the Gapon equation. A strong temperature dependence of Ca-Na exchange has been shown recently in column studies by J. Griffioen and C.A.J. Appelo (unpublished data). It seems likely that differences among cation exchange sites on the expansible clays (i.e., interlayer sites located on planer surfaces versus those on edge sites and sites on layers with significantly differing charge density) contribute to the variation in cation selectivity with changing temperature and Na exchange fraction. The edges of smectites (e.g., montmorillonite), which comprise ca. 20% of the CEC of these clay minerals, presumably have different selectivities than interlayer surfaces for heterovalent cation exchange. Thus, at < 20% Na saturation of montmorillonite, Na occupies primarily the exterior sites, while Ca dominates interlayer sites (Levy et al., 1983). High-charge exchangers, such as vermiculite and bidellite, may exhibit greater variation in selectivity than lower-charge smectites because of 12-fold coordination with certain mono-valent cations such as Cs, K, Rb, and NH4 and also because of demixing. Demixing results from the tendency of cations of similar charge and hydrated radii to be found in interlayers of similar average charge and to prefer interlayers which are already predominately saturated with exchangeable cations of similar charge and hydrated radii. 3 MINERAL PRECIPITATION 3.1 Fe and Mn oxyhydroxides Surface waters often contain significant levels of dissolved Fe and Mn, and they frequently gain additional quantities of these metals during recharge through soils and other surficial sediments. Surface water, and the soil and sediment through which the water infiltrates,
generally contain sufficient organic material to support an abundant microflora. Since oxygen serves as the initial electron receptor for microbial metabolism, a loss of oxygen and a lowering of the "system" redox potential of the infiltrating water generally occur during recharge. The loss of oxygen and lowering of the redox potential tend to increase the concentration of dissolved Fe and Mn in shallow groundwater. When this water subsequently encounters free oxygen in an ATES system, hydrous oxyhydroxides of Fe and Mn readily form. Such precipitates are frequently encountered in ATES systems in the Scandinavian countries, where a majority of the ATES systems have been located in shallow aquifers of glacial origin. These precipitates may decrease the maximum injection rate as at the Bunnik ATES site (Bredero Energy Systems, 1986) when a leaky connection allowed the entry of air into the system. Traditional solutions to the problem of Fe- and/or Mn-rich water are to either remove these metals from the Fe- and Mn-bearing water or to totally exclude oxygen from the ATES system. Sufficient Fe and Mn may be removed by allowing the water to cascade onto a lowslope area where it flows in a thin layer over a rough surface, followed by slow sand filtration (Hatva et al., 1984). A more novel approach is to inject nitrate into the aquifer down gradient from the source well and allow microbial activity to promote the activity of Fe(I1) oxidizing microflora and allow the Fe(II1) oxides to precipitate in situ. This technique can reduce dissolved Fe to fractional milligrams per liter levels (Vanek, 1990). Alternatively, water containing elevated levels of Fe and Mn can be used without their removal where 1) the storage aquifer is isolated by aquicludes of low permeability and 2) atmospheric oxygen is totally excluded from the ATES system. The problem of Fe oxyhydroxide clogging at the Dutch Bunnik site was circumvented by using low-Fe municipal water for the initial heating and injection in conjunction with steps to prevent air from entering the system (Cowering and Appelo, 1988). 3.2 Carbonates As carbonate minerals are nearly ubiquitous, the waters of many if not most ATES systems are close to equilibrium with calcite. This may be the case even when the mineral is only a minor constituent, e.g., < 0.4% of the aquifer matrix, as in the Fontainebleau sand at Saint Quentin (Yvelines, France) (Vinsot, 1987). The Plaisir site near Paris, France, is
Page 1 and 2: 4 'Hydrochemistry and energy storag
Page 4 and 5: CONTENTS AUTHORS INTRODUCTION J.W.
Page 6 and 7: 4 Corrosion 5 Some conclusions Refe
Page 8 and 9: AUTHORS 0. Andersson VIAK AB P.O. B
Page 10 and 11: INTRODUCTION J.W. Lyklema This volu
Page 12 and 13: THE INTERNATIONAL ENERGY AGENCY AND
Page 14 and 15: 3 THE IEA The International Energy
Page 16 and 17: In addition to projects in the doma
Page 18 and 19: THE RELATION BETWEEN AQUIFER THERNl
Page 20 and 21: 3 VIABILITY ATES systems contribute
Page 22 and 23: Figure 4 Temperature fluctuations o
Page 24 and 25: 10°C between two cycles. We have t
Page 26: groundwater quality so seriously th
Page 29 and 30: developed within Annex VI (Environm
Page 31: carbonate phase, the use of a high-
Page 35 and 36: precipitation from solutions at nea
Page 37 and 38: of the water for storage. These tre
Page 39 and 40: the higher ATES temperatures. There
Page 41 and 42: One of our research objectives is t
Page 43 and 44: COUDRAIN-RIBSTEIN, A. and GOBLET, P
Page 45 and 46: SPOSITO, G, and LeVESQUE, C.S. ; 19
Page 47 and 48: saturation with respect to calcite
Page 49 and 50: system would influence the hydroche
Page 51 and 52: columns were heated from 11°C to 9
Page 53 and 54: (Table 2), clearly shows that the i
Page 55 and 56: Plate 1: CaC03 grain from first cen
Page 57 and 58: decrease in ca2+ activity, to reach
Page 59 and 60: y thermodynamic equilibrium calcula
Page 61 and 62: HOLM, T.R., EISENREICH, S.J., ROSEN
Page 63 and 64: INTRODUCTION The use of aquifers fo
Page 65 and 66: As can be seen "cloggingn has been
Page 67 and 68: specific capacity of the well and c
Page 69 and 70: the water being injected. The reaso
Page 71 and 72: Figure 5 Simplified stability diagr
Page 73 and 74: 3.4 Clogging by organic slime Clogg
Page 75 and 76: 4 CORROSION 4.1 Forms of corrosion
Page 77 and 78: When halogens are known to be prese
Page 79 and 80: available on the market. SOME CONCL
Page 82 and 83:
BIOGEOCHEMICAL ASPECTS OF AQUIFER T
Page 84 and 85:
In accordance with Figure 1 mangane
Page 86 and 87:
at a neutral pH is kinetically dete
Page 88 and 89:
of such biocides used against desul
Page 90 and 91:
HYDROGEOCHEMICAL TRANSPORT MODELLIN
Page 92 and 93:
The complexity of the models with a
Page 94 and 95:
The comparison shows that inclusion
Page 96 and 97:
the component O2 (Oxygen) has been
Page 98 and 99:
The results of a recent solubility
Page 100 and 101:
The neutral "exchangeable" complex
Page 102 and 103:
SrC12 elution of Delft sediment, sh
Page 104 and 105:
The saturation ratios can be used i
Page 106 and 107:
Recovered water in the long term te
Page 108 and 109:
Cumulat~ve Flow (103m3) Cumulative
Page 110 and 111:
Dissolution of silicates is in much
Page 112 and 113:
KIRKNER, D.J., and REEVES, H.; 1988
Page 114 and 115:
WATER TREATMENT AND ENVIRONMENTAL E
Page 116 and 117:
Table 1 Ove~iew of chemical treatme
Page 118 and 119:
calculated with a computer model th
Page 120:
Figure 1 Schematic representation o
Page 123 and 124:
addition shows an increase in neces
Page 125 and 126:
Table 4 summarizes the primary envi
Page 127 and 128:
wsts for this overdimensioning may
Page 129 and 130:
_? Primary circuit Figure 7 Reactor
Page 131:
Problems with iron precipitation ca
Page 134 and 135:
RESEARCH ON HYDROCHEMISTRY AND WATE
Page 136 and 137:
ANNEX XI L - -1 I Figure 1 Relation
Page 138 and 139:
stores. F. To test selected water t
Page 140 and 141:
(Fe, Ca, Mg) solid solutions. The p
Page 142 and 143:
corrosion and scaling rates under d
Page 144:
the industry. For this treatment no
Page 149 and 150:
Water nuisance. Proceedings of Tech
Page 151:
No. 36 No. 37 No. 38 Urban storm wa
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Hydrochemistry and energy storage in aquifers - NHV.nu

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