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CHEMISTRY, MATERIALS, SOIL, AQUATIC CHEMISTRY, AIR, BASICS, Missing the…

- - - - Industrially produced
        
        Soda ash
        
        Potash
        
        Borax
      - Natural
        
        Limestone and dolomite
        
        Feldspart
    - - Colorants
      - Recycled scrap glass
  - - - Clarifying with gas bubbles
  - - - 70-75% SiO2, 6-11% CaO, 13-15% Na2O
      - Crystal glass
      - Flameproof
- - - - Lime + fine quarz sand + water
      - Pressing into moulds
      - Strong, Chemically stable
    - - fine quarz sand + cement + water + lime
      - Aerated by aluminum
      - Released hydrogen causes foamng (bubles)
- - - - Water repelling treatment (Organic molecules with long hydrocarbon chains
    - - Water and dissolved compounds retained in pores
      - capillary pores
      - Voids
      - Gel pores
  - - - Temp changes
        
        Periodinc heating and cooling => volume changes
        
        Cracks lead to irreversible volume increase
        
        Uneven heating due to sun
      - Moisture (water removable by drying)
        
        Capillary movement
        
        Dissolution of aggressive compounds
        
        Acids, salts, CO2
        
        Salts may crystallize when saturated sollution dries out
        
        Microorganisms
        
        Frost damage
        
        For ceramics - slow rehydration of fired clay materials
    - - Highly soluble salts
        
        Sources
        
        Component of material
        
        Ground waters
        
        Acid rain
        
        Deicing agents
        
        Animal byproducts
        
        Saturation and crystalization on the surface
        
        Crystallization pressure in pores leading to cracks
        
        May be prevented by forming bigger voids in material
      - Dissolution of CaCO3 by acids
        
        In limestone
        
        in mortars
        
        In plasters
        
        In concrete
      - Atmosphere
        
        CO2
        
        Carbonation of mortars - good - formation of calcite
        
        Carbonation of concrete - bad - corrosion of reinforcements
        
        Dissolution of carbonates (Dissolution of calcite)
        
        Formation of carbonic acid
        
        Sulphur and Nitrogen oxides - form acids
    - - sulphur and nitrifying bacteria:
        
        Source of soluble salts
      - Fungi
        
        Feed on wood
        
        Destroy material by growing mycelium fibers
        
        Produce acids
      - algae
        
        Produce CO2
        
        Produce acids
        
        Coloured slimy coatings
        
        Expansion in pores
      - Plants and animals
  - - - Ca(OH)2 from cement is dissolved by pore water
      - Dangerous for ground waters amd underground structures
      - Need proper waterproofing
      - decrease in pH => damage to steel reinforcements
      - calcite efflorescence on the surface
    - - Acids turn Ca(OH)2 into salts
      - Carbonation of concrete (calcite formation)
    - - Sulphate expansion (SO4- turns calcite into sulphate)
      - Magnesium expansion
    - - Due to high pH
      - Causes loss of contact between steel and concrete
    - - Alkali-silica reaction
      - Results in gel of sodium silicate that absorbs water
      - Expansion
- - - - Portland cement = portland clinker + gypsum
        
        Production: raw materials - rotary kiln - portland clinker - milling - resulting in cement and admixtures
        
        Clinker - crushing milling and homogenization of raw materials (Smaller particles fused together - reduction in porosity) Clinker minerals are produced due to heat
        
        Milling: Cooled particles of clinker crushed to fine powder and mixed with additives. Finer cement - faster hydration
        
        We need CaO, SiO2, Al2O3, Fe2O3 (Ca, Fe, Al silicates)
        
        Made from cement stone (CaCO3 76-78% +Clay minerals)
        
        Hydraulic modulus 1.7-2.3 (Mh=[CaO]/[]+[]+[])
      - Blended cement
        
        Reasons
        
        Producing clinker is Energy intensive and expensive
        
        Lower E consumption
        
        Waste recycling
        
        Lower CO2 emissions
        
        Lower cost
        
        Possible better durability
        
        Admixtures
        
        Silica fume (pozzolana)
        
        From silicone production
        
        Fine particles of amorphous SiO2
        
        High specific surface - high reactivity with lime
        
        Blast furnace slag
        
        Mix of Ca silicates
        
        Hot sag is cooled and sorted
        
        Fine fraction as latent hydraulic binder
        
        Coarse fraction as aggregates
        
        Coal fly ash - Waste from coal combustion
        
        Milled limestone
  - - - Made from limestone with various Calcite content
      - Production: Shaft furnace limestone+coal - CaCO3 -> CaO + CO2 - cooling of CaO
        
        Slacking (Mixing with H2O, results in Ca(OH)2 + E)
        
        Wet (water in surplus) - saturated slurry of Ca(OH)2
        
        Dry (1:1 water:lime) - dry powdered Ca(OH)2 - diluted inn water on site
        
        Setting (part of water is dried and absorbed)
        
        Hardening Ca(OH)2 back to calcite - Ca(OH)2 + CO2 -> CaCO3 + H2O
        
        Forms
        
        Dry powder for easy handling and transport
        
        Lime slurry
        
        Whaitewash (very diluted lime for facade painting)
        
        Limewater (spraying for restoration of historic plasters)
      - Types
        
        Burnt lime (<1050C)
        
        high porosity
        
        high specific surface
        
        fast rection with water
        
        binder in mortars and plasters
        
        Overburnt (dead) lime
        
        lower porosity
        
        slow reaction with water
        
        production of AAC (autoclaved aerated concrete)
    - - Naturally CaSO4*2H2O
      - FGD gypsum flue gas desulfurization – from coal power plants
      - by-product of some chemical procsses
      - Dehydration
        
        Hemihydrate at 110-150C (CaSO4 * 1/2H2O)
        
        Alpha (closed vessel, overpressured, large crystals)
        
        Beta (atmospheric pressure, irregular porous crystals)
        
        Anhydrate over 180C (CaSO4)
      - Setting
        
        hemihydrate dissolves in mixing water
        
        crystallization of dihydrate from solution
        
        growing crystals are creating a „mesh“→ setting
        
        drying out of surplus water - hardening
      - Applications
        
        Fast setting gypsum (2min set, 15min hard.)
        
        construction gypsum: more β (dry wall, electrical wiring)
        
        stucco: α + β hemihydrate
        
        moulding gypsum – α hemihydrate – ceramic moulds
        
        Dry wall (hemihydrate + cellulose fibers, starch)
        
        Interior renders
        
        Flooring (Slow setting Anhydrate. 20min set, 10-40h hard.)
- - - - Mineral grains glued together with amorphousa glass
  - - - By function
        
        Plastic component (Kaolin, clays, earths)
        
        Very fine particles
        
        Clay needs to be homogenised
        
        Kaolin - most expensive material
        
        Non plastic component (high melting point) Quarz or sand etc
        
        Reduces shrinkage during drying and firing
        
        Better workability
        
        Better mould separation
        
        Lightening additives (saw dust, coal powder) for higher porosity
        
        Fluxing component (low melting point) Feldspar
        
        Forms melt during firing, binding clay particles together
        
        Forms glassy matrix in fired ceramics
      - By origin
        
        Natural (clay, feldspar, sand)
        
        Synthetic (intermediates for engineering ceramics Al2O3)
        
        Secondary (fly ash, saw dust)
    - - Dry powder (spray dryer)
      - Plastic (filtration of slurry in a filter press)
      - liquid slurry (adding water)
    - - Vacuum press
      - Pressing
      - Isostatic pressing (liquid and dry)
      - Casting (liquid) for complicated shapes
    - - Sintering - particle form compact solid matter
      - Volume shrinkage, possibility of cracking
      - Slow process to prevent cracks
    - - Tunnel or box furnace
      - Residual water dries out, clay minerals dehydrate, Clay particles sinter, flux component melts
    - - Glaze = Glassy layer based on SiO2 Non porous
  - - - Porcelaine
        
        White, Low porosity
        
        High content of glassy phase (25% feldspar)
        
        Two phase firing
      - Sanitary ceramics
        
        Simillar to porcelein
        
        Porosity to 5%
        
        White
        
        Shaped by casting
        
        Chem and Mech resistance, easily cleaned
      - Earthware
        
        Porosity over 10%
        
        50% clay 40% quartz 10% feldspar
        
        Lower firing temp
        
        Usually glazed or covered with engobe
        
        Used for tiles
    - - Stoneware
        
        Hard, low porosity, high compressive strength, high chem resistance
        
        Stoneware clay- low shrink - large products
        
        Colored by Fe oxides
        
        FELDSPAR CONTENT
        
        high - Fine stoneware - low porosity, durable (paving)
        
        low - Coarse stoneware - sewer tubes, agriculture
      - Brickware
        
        Red due to Fe
        
        High porosity => low thermal conductivity
        
        Lightening additives (saw dust, coal)
    - - Acid (with SiO2, Al2O3) suitable for acidic melts (glass)
      - Basic (with MgO) suitable for basic melts (iron, cement)
    - - Casted basalt
        
        Casting
        
        Controlled slow cooling to allow crystalization
        
        Utilized in aggressive environments
      - Mineral fibers/Mineral wool
        
        Basalt+slag (80:20)
        
        Melt is fiberised and glued with resin
- - - - Vacancy
      - Interstitial atom
  - - - Casting
        
        Gravitational
        
        Centrifugal
        
        Pressure casting
      - Forming
        
        Cold or hot rolling
        
        Forging
        
        Extrusion
        
        Drawing
      - Joining
        
        Mechanical
        
        Welding
        
        by gas
        
        By electric arc
        
        by ohmic heat at contact of two pieces
        
        by thermite
        
        Soldering (different metal with lower melting point)
- - - - Hard
      - Chemically stable
      - Source: Quarz sand
    - - large group of rocks-forming minerals. Chemicaly: dual silicates (e.g. potassium aluminum silicate)
      - Composition given "in oxides"
      - Occur in most igneous rocks
    - - Contain bound water
        
        with water - plastic mixture
        
        after firing - hard
      - Laminated structure => plasticity (Layers are destroyed during firing)
  - - - Sedimentation of mollusc shells
      - Production of lime, aggregates
      - Sensitive to acid and CO2 - dissolved
  - - - Good workability
      - Low chemical resistance
- - - - Gravel (sediments)
      - Crushed (from rocks)
        
        Production: Mining - crushing - grading
    - - thermally expanded clay production: Clay Mining - Clay granulation - burning with small coal particles in a rotary kiln at 1100C - Flue gas from burning coal causes foaming of clay - resulting porous clay particles with low bulk density
    - - Recycled debris from building industry (must be graded)
      - Challenging to ensure constant properties
- - - - Industrial activities
      - Leakage of toxins
      - Fertilizers
    - - Atmosheric deposition
      - Agricultural and industrial practices
- - - - 50% of volume
      - Particles of different size
      - Originate from parent bedrock
    - - Edaphon (living matter)
        
        Phytoedaphon (bacteria, fungi, cyanobacteria, algae)
        
        Zooedaphon - process organic matter, move material around
      - Humus (dead matter)
        
        Arises from dead organisms
        
        Stabilizes soil structure
        
        Source of nutrients
        
        Source of food for soil organisms
  - - - Substance transfer
      - Selfcleaning function
      - Plant growth
    - - Capillary
      - temporary gravitational (from rain)
      - Chemically bound
- - - - Bedrock + weathered material
      - Sediments
      - Older soils
    - - Precipitation (intensity of soil washing)
      - temperature (affects decomposition rate)
    - - Height
      - Slope degree
      - Exposure to air
- - - - Epilimnon (warm water) on the top
      - Hypolimnon (cold water) on the bottom
      - Metalimnon (Thermocline) in between
      - Shallow mixing due to daily temperature changes
    - - Cooling of surface layers
      - Mixing with deeper layers (with wind?)
      - Thermocline descends
      - Homothermia at 4C
    - - Ice at the top
      - Ice cools down the top water below 4C
      - The heavy 4C water is at the bottom - the warmest layer
    - - Ice Melts and the water warms up to 4C, Which causes it to descend, causing mixing
  - - - Concentration of ions
      - charge number
      - Mobility
      - Temperature
    - - 0.05-0.3 - distilled
      - 5-50 - Surface and groundwater
      - Drinking = 40
      - Industrial waste = up to thousands
  - - - Anaerobic
        
        No oxygen of any kind. Negative ORP. Formation of Methane and Sulphane
      - Aerobic
        
        Positive ORP
      - Anoxic
        
        ORP too high (150-250mV) No free oxygen but O is bound in compounds (e.g. NO3)
  - - - Animal products, clays, Fe
    - - H2S, decomposition processes, microorganisms
    - - Suspended solids, colloids, clay particles, plankton and bacteria
  - - - 6-8.5 Naturally
      - 8 no CO2 (absorbed by plants)
      - <6 Acidified lake
- - - - Greatest capacity
    - - Least capacity, Doesnt retain water for long
  - - - Condensation
      - Precipitation
      - Runoff
        
        Surface
        
        Snowmelt
        
        Streamflow
      - Infiltartion
        
        Seepage
        
        Springs
        
        Groundwater flow
      - Sublimation/Desublimation
      - Evapotranspiration
        
        Transpiration
        
        Water from soil goes through roots to leaves – outgoing in the form of vapor into atmosphere
        
        Evaporation
        
        Caught rainwater
        
        Water from the ground
      - Evaporation
    - - Decrease in quality
      - Decrease in available water sources
      - In urban areas
        
        Impermeable areas prevent infiltration, stop groundwater resupply and leas to floods
- - - - Atmosphere
      - Soil and rocks
    - - Industrial, domestic waste
      - impurities from the air
  - - - Organic
      - Inorganic
        
        Ca2+ and Mg2+
        
        Naturally occurring
        
        Ca:Mg 4:1
        
        Biogenic
        
        affect water hardness, lead to limescale
        
        Ca deposits in pipes
        
        Mg is aggressive to concrete
        
        Al
        
        Naturally occurring Al silicates
        
        Toxic for plants and fish
        
        Potentially toxic for humans
        
        Heavy Metals (Selenium and Arsenic)
        
        Toxic for humans
        
        Cadmium
        
        Mercury
        
        Lead
        
        Arsenic
        
        Ions are more dangerous than neutral atoms
        
        Fe
        
        Biogenic, but bad organoleptic properties; clogging of pipes
        
        Manganese
        
        Important for organisms but bad organoleptic properties
        
        Copper and zinc
        
        Essential for humans
        
        Toxic or fish and algae
        
        Taste effects
        
        Chromium
        
        Toxic for fish
        
        Important for humans but potentially carcinogenic
        
        Cause color and taste
        
        Halogens
        
        Fluorine
        
        From minerals and from power plants exhausts
        
        Good for bones and teeth in moderation
        
        Chlorine
        
        Rock salts, domestic wastewaters, deicing applications
        
        Toxic, taste effects
        
        Iodine
        
        Sulfur compounds
    - - Diluted
        
        Electrolytes (Ca2+, Mg2+, Na+, NO3- etc)
        
        Non-electrolytes (O2, CO2, compounds of B and Si)
      - Suspended
- - - - Acidifying compounds
        
        NOx (combustion)
        
        SO2 (industry, coal)
        
        CO2
      - Degrees of acidification
        
        First, HCO3- in the environment buffers the decrease in pH. pH stays const but amount of HCO3- is decreasing
        
        When HCO3- is deplited , pH starts to decrease as there is nothing to neutralise the H+. This leads to dying of fish
        
        pH= 4.5 reached. Decrease stops as Al(3+) and humic substances start to buffer H+. Al concentration is increasing. Extinction of aquatic biota.
      - Consequences
        
        Soil Acidification
        
        Decrease in neutralization capacity of groundwaters. Increase of concentrations of some elements Al, Cu, Zn, Cd
        
        Vegetation impact. - disappearance of mosses and lichens,
        weakening the resilience of forests against natural pests
        
        Technological problems
        
        Corrosion of building materials
        
        Water treatment insufficiency
  - - - Winter smog (Particulate matter, NOx, SO2, CO)
      - Summer smog (NOx, O3)
    - - Size
        
        Coarse (>50 μm)
        
        Fine (1-50μm)
        
        extremely fine (<1μm)
      - Origin
        
        natural (volcanic, sea salt, bio, cosmic dust, smoke from forest fires)
        
        Condensation cores
        
        Allergies
        
        Airway diseases
        
        Artificial (combustion, agriculture, smoking, industry)
        
        Negative affects on flora and fauna
        
        Breathing difficulties, reduced light intensity
        
        Effects on buildings