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Environmental technology:water purification and soil
No.3
water purification and soil remediation
March, 2013 Toyohisa Fujita,
Energy and Environmental course,Graduate school of Engineering, RACE
The University of Tokyo, [email protected]
1. Water purificationOutline of wastewater treatment of old mine drainage in Japan
The University of TokyoProf. Toyohisa Fujita
[email protected] @ y y jphttp://park.itc.u-tokyo.ac.jp/tfujita-lab/
Environmental standard and effluent standard of some metals and pH in Japan (2013)
*In case of wastewater related on drinking water.
Amount of waste water and treatment cost of old mine drainage in Japan from 2003 to 2012.
JOGMEC (Japan Oil, Gas and Metals National Corporation) (2013), http://www.jogmec.go.jp/jogmec_activities/mp_control_metal/technology/index.html
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Reaction equations of minerals with water and air
Sulfide minerals
Precipitation
From AIST, Japan
Effect of acid mine drainage
Chi F ji iChina, Fujian province
Japan, Kitakami river
Matsuo neutralization plant of acid mine drainage, Japan
Some wastewater treatment methods of old mine drainage in Japan
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Wastewater treatment types of old mine drainage in Japan
Old mine drainage places in Japan planning the waste water treatment from 2013 to 2022.
Pollution control plan of old mine drainage in Japan from 2013 to 2022
Mine owner exsistenceMine ownerless
Civil engineering works to prevent mine pollution
Tunnel, places 29 28Stockyard, places 49 15C 83 1
Old mine type
Cover soil, hectare 83 1Planting, hectare 70 2Retaining wall, m 0 1478Dam, m 154 0Drainage ditch, m 10,903 4,765Repair work of facility, places 8 5
Total waste water treatment Old mine drainage place, number 55 24Total waste water amout, million m3/year 5.46 1.53Cd in waste water, t/year 9 0.2Pb in waste water, t/year 144 1.5As in waste water, t/year 11 23Cu in waste water, t/year 194 46Zn in waste water, t/year 1985 50Fe in waste water, t/year 3783 2703Mn in waste water, t/year 1238 51
As received wastewater; pH 3.7, Cd 0.2, Cu 6.4,
Pb 0.7, Zn 23, T SO4 590,T. Fe 6, SiO2 70 ppm
Flow sheet to remove cadmium ion from mine effluent using flotation.
Jeyadevan, B. et al. (1999). Treatment of old yoshino mine drainage and removal of cadmium ions: Proc. Global Conf. on Environmental and Metallurgy, GME ’99, Beijing, China; The Nonferrous Metals Society of China.
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The distribution of arsenic(III) and arsenic(V) species in water in the presence of the iron
compound as a function of pH, showing the total adsorbed As (denoted as “Total ADS As”)
100 100
20
30
40
50
60
70
80
90
100
Tota
l Con
cent
ratio
n of
As3+
, (%
)
AsO3-3
Fe(wk)H2AsO
3
HAsO2-3
H3AsO
3
H2AsO-
3
H4AsO+
3
Total ADS AsO3-3 20
30
40
50
60
70
80
90
AsO3-4
Fe(wk)HAsO-4
Fe(wk)H2AsO4
HAsO2-4
H3AsO
4
Fe(wk)OH-AsO3-4
Total ADS AsO3-4
otal
Con
cent
ratio
n of
As5+
, (%
)
1 2 3 4 5 6 7 8 9 10 11 12 13 140
10
T
pH1 2 3 4 5 6 7 8 9 10 11 12 13 14
0
10To
pH
a. As(III) b. As(V)(Input Parameters - As concentration: 2.7 x10-5 mol/L;
Fe concentration :1 x10-3 mol/L)
Adsorption isotherm of arsenic species onto FeCl3-based and poly-Fe-based adsorbents (experimental conditions: initial As concentration: 2mg/L, adsorbent dosage: 0.01–20 g/L, contact time: 120min, pH of solution 7, and T=25oC).
Equilibrium concentration of arsenic species as a function of contact time (experimental conditions: initial As concentration: 2 mg/L, adsorbent dosage:0.1 g/L, contact time: 10–300min, pH of solution 7, and T=25oC)
• Cr removal
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(a) SEM image for pineapple leaves before adsorption(a) (b)
(a) SEM image for pineapple leaves before adsorption, (b) SEM image for 723 K carbonized pineapple leaves after Cr6+ ion adsorption.Ponou, J. et al. (2011). Sorption of Cr(VI) anions in aqueous solution using carbonized or dried pineapple
Leaves: Chemical Engineering Journal, 172, 906– 913.
Effect of contact time on the removal of Cr(VI) anions by 723 K carbonized pineapple leaves (PL723), 623 K carbonized pineapple leaves (PL623) and dried pineapple leaves (PL): initial pH = 2; initial concentration: [Cr(VI)] = 5 mg/L; adsorbent dosage 10 g/L; temperature 293 K.
Distribution of Se(VI) species and the total adsorbed Se (Total ADS Ae) as a fuction of pH.
Effect of pH on removal of selenium (VI) ion by adsorbent of ferric cupric hydroxide powder.
(○：adsorption capacyty, □：concentration of copper,conditions : adsorption period 2 h, 298K)
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(a) SEM image of surface of natural dolomite (As received ore)
(a)---2mm (b)--100nm
received ore)(b) SEM image of calcined dolomite surface(Calcined dolomite in 750 oC for 0.5 hour, D750n)Kuriwada, A. et al. (2012). Boron Removal and Recovery
by Adsorbing Effect of Boron on Thermally Treated Dolomite in the Water Containing Boron Ion
Effect of calcination temperature of dolomite on boron adsorption for long term.Adsorbent: Dn; Natural Dolomite, Dc750; Calcined dolomite at 750oC for 30 min. Dc850; Calcined dolomite at 850oC for 30 min., Dc950; Calcined dolomite at 950oC for 30
min., Dc1050;Calcined dolomite at 1050oCfor 30min., Amount of adsorbent; 500mg/25mL, Initial boron concentration, 652mg/L, Particle size ; -75μm
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Heavy metal concentrations and pH in the as received Ashio acid mine drainage sample as well as the effluent standards in Japan
Wang, L. P. et al. (2013). Investigrating sulfidization with neutralization treatment for selective recovery of copper and zinc over iron from acid mine drainage (AMD): Mineral Engineering, in print
Flow sheet to recover Cu, Zn and Fe in the precipitate generated at each treatment stage.
Water pollution
8
0.003
0.1
Ｎ as nitric acid 10
Ｆ 0.8 8
Ｂ 1 10
Ｚｎ 0.03 2
Inorganic species• Cyanide: HCN in water A week acid
[ ][ ][ ]
10106 −−+
== xHCN
CNHKaA week acid Strong affinity for many metal ions.Less toxic Fe(CN)6
4-
Volatile HCN is very toxic.・Ammonia and other inorganic pollutantsAmmonia: Exessive levels of ammoniacal nitrogen cause
water quality problems pKa=9 26
[ ]HCN
water quality problems. pKa 9.26Hydrogen sulfide: H2S is a weak diprotic acid . Affinity for
many heavy metals as metallic sulfides.
[ ][ ][ ] 996
2
1
1 .SHHHSlogpKa =−=
+− [ ][ ][ ] 92122
2 .HS
HSlogpKa =−= −
+−
• Nitrite ionNO2
- occurs in water as an intermediate oxidation state of nitrogen over a relatively narrow pH range.
・Sulfate ionSO2
2- is found in some industrial wastewaters. Sodium sulfide is commonly added to boiler feed waters as an oxygen scavenger:2SO3
2- + O2 → 2SO42- (N2H4 + O2 → 2H2O + N2(g))
The pKa1 of sulfurous acid is 1.76 and pKa2 is 7.20., sulfite exists as either HSO3
- or SO3- in natural water.
・Perchlorate ionClO h d t ll ti bl iClO4
- has emerged as water pollution problem in some areas. Perchlorate in water is very unreactive, and all common perchlorate salts other than KClO4 are soluble, so it is difficult to remove. EPA standard in drinking water: 1ppb
・Asbestos in water
Oxygen, Oxidants and reductantsThe degree of oxygen consumption by microbial
mediated oxidation of contaminants in water is called the biochemical oxygen demand BOD.
This parameter is commonly measured y determining the quantity of oxygen utilized by suitable aquatic microorganisms during a 5-day period.
{CH2O} + O2 ----- CO2 + H2ONH4
+ + 2O2 → ２H+ + NO3- + H2ONH4 2O2 ２H NO3 H2O
4Fe2+ + O2 + 10H2O →4Fe(OH)3(s) + 8H+
2SO32- + O2 →2SO4
2-
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The addition of oxidizable pollutants to streams produces a typical oxygen sag curve.
Organic pollutants• Sewage
Disposal problem of sewage in ocean
Biosorption
10
11
12
Phytoremediation
As Adsorption
Fern
Passive treatmentCalcite
Organic materials
Utilization of wallAnaerobic wetland
Clean water
PRB: Permeable reactive barriers
From AIST, Japan
2. Soil quality and remediationq y
The University of TokyoProf. Toyohisa Fujita
[email protected] @g y y jphttp://park.itc.u-tokyo.ac.jp/tfujita-lab/
Clay minerals and soilsWeathering of silicates
13
Primary mineral weathering
14
Bulk of clay particle
Organic matter
15
Soil Washing
16
17
18
19
2.4mm diameter
Quiz: waste water
1. List functional groups related on the biosorption.2. Why is the ferrous oxidizing bacteria used to clean the acidic y g
mine drainage containing Fe2+ ion.3. Calcium carbonate and calcium hydroxide are common used
to neutralize the acidic drainage. Write the problems to use these alkaline materials.
Quiz: Soil washingg1. List four groups used in the soil cleaning process.2. Write three difference cases of contaminated soil.
