lunds universitet / lth / 2009-02-26 tillämpad vattenkemi 2010 applied aquatic chemistry 2010...
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Lunds universitet / LTH / 2009-02-26
Tillämpad vattenkemi 2010Applied Aquatic Chemistry 2010
Jan-Olle Malm
Lars Stenberg
Deptartment of Chemistry
Per Warfvinge
Department of Chemical Engineering
Lunds universitet / LTH / 2009-02-26
After the course, you should:
• understand key chemical processes in surface waters and groundwaters
• be able to apply your knowledge about chemical equilibrium on real-world problems
• have developed your computation skills
• be able to interpret chemical phenomena and express your ideas in writing
Lunds universitet / LTH / 2009-02-26
What we do
• Basic chemistry – lectures by Jan-Olle Malm
• Applied Water Chemistry – lectures by Per Warfvinge
• Exercises and preparation of a workbook
• Labwork– The CO2/water system– Chemical analyses and charge balance– Microbial redox reactions
Lunds universitet / LTH / 2009-02-26
Perspective: Water chemistry as a result of complex interactions
Lunds universitet / LTH / 2009-02-26
• Limited climatic change • Fresh air• Only natural acidification• High quality groundwater• Vital lakes and streams• Vibrant wetlands• Oceans in balance• No eutrophication• Diverse forests• Rich farmland• Great mountains• Good built environment• Safe radiation• Protective ozone layer
Water Atmosphere
National environmental goals:
Lunds universitet / LTH / 2009-02-26
Links to previous courses
• Hydrology and aquatic ecoogy– Links between chemistry and biology– Growth limiting element, carbon sources
• Physics– Balances, thermodynamics, computations
• Geology– Link bedrock/soil to water quality– Open and closed aquifers
• Themodynamics– Equilibrium concept, ”free energy”, kinetics
• Mathematics– Algebraic equations (dependence, rank)
Lunds universitet / LTH / 2009-02-26
…and further on
• Statistics W3– Computational skills
• Masstransport W3– Modeling of dynamic systems– Chemistry in a context– Contaminant transport in groundwater
• Environment and Management W3– Link environmental issues - environmental legislation – Environmental assessment
• Degree project and – work!
Lunds universitet / LTH / 2009-02-26
What does an Environmental engineer need to master?
• Processes dealing with the pH and redox-conditions in water
– Gas-water interactions
– Acid-base equilibria
– Dissolution and precipitation reactions
– Reduction - oxidization reactions
• Less important
– Phase distribution equilibria
– Complexing
Lunds universitet / LTH / 2009-02-26
Key chemical concepts
• Equilibrium
• Equilibrium equations
• Charge neutrality
• Charge balances
Lunds universitet / LTH / 2009-02-26
Water chemistry units
• mol/L– Used for equilibrium/kinetic calculations
• mg/L– Commonly uses for N and P
• eq/L or molc/L– equivalents/L = charge * mol/L– Commonly used for comparisons and trend analysis– Can be used to set up charge balances
Lunds universitet / LTH / 2009-02-26
The Charge Balance - Stream water from the Kålmården area
Lunds universitet / LTH / 2009-02-26
Most important acid-base system in nature: CO2-water
Lunds universitet / LTH / 2009-02-26
Water chemistry: First week
Date Time Room Type Instructor
Mon 15/3 10-12 B Lecture, AWC 1-2 PW
13-14 F Lecture, AWC 1-2 PW
20-21 Read AWC 1-2
Tue 16/3 10-12 G Lecture, Chang 15/16 (pH) JOM
15-17 H, I Exercise JAM, MP, JOM
Thur 18/3 13/19 Lab 1 JAM, MP
Fri 19/3 8-10 H, I Exercise JAM, MP, JOM
13-15 F Lecture, Chang 17 (buffers) JOM
15-19 Lab 1 JAM, MP
Lunds universitet / LTH / 2009-02-26
Sensitivityof aquatic species to pH
pH 4 pH 5 pH 6
ål
gädda
abborre
harr
mört
bäckslända
dagslända
snäcka
kräfta
sötvattensmärla
bäckbräsma
vitmossa
Lunds universitet / LTH / 2009-02-26
Key chemical concepts
• Equilibrium
• Equilibrium equations
• Charge neutrality
• Charge balances
Lunds universitet / LTH / 2009-02-26
Global reservoirs of water
Lunds universitet / LTH / 2009-02-26
Laboration 1:Equilibrium gas/liquid
• CO2 in N2 is bubbled through ”pure” water
• Experimental determination of gas-liquid equilibrium
constant
• When: Wednesday - Thursday
• Where: Level 0, labs close to Ideon
• Staff: Jenny Axén Mårtensson, Malin Rosenberg
Lunds universitet / LTH / 2009-02-26
Globally most common ions in surface waters/ground waters
AnionReference value
mmole/LCation
Reference valuemmole/L
HCO3- 3 Ca2+ 1
SO42- 0.1 Na+ 1
Cl- 0.1 Mg2+ 0.4
NO3- 0.01 K+ 0.05
Sr2+ 0.001