Water Flashcards
Hard water
Is high in minerals or ions. Water hardness is mainly calcium and magnesium cations, along with bicarbonate, carbonate, sulphate, chloride or nitrate anions.
- high in calcium and magnesium salts
Soft water
Is low in ions
Ions
Are an atom, or group of atoms, that has a net positive charge (cation) or negative charge (anion). Anions and cations when combined are called salts so we can also say that hard water is high in calcium and magnesium salts
70% of the earths surface is water
97% of the earths water is saltwater in oceans
2% is fresh water in ice caps
0.6% is ground water (boreholes and springs)
0.4% is fresh surface water (rivers, lakes, reservoirs)
Surface water (rivers, lakes, reservoirs)
Typically soft, with low mineral content.
Higher level of organic material, open to pollution from cities l, towns and agricultural run off.
Borehole (ground water)
Has a mineral content because it is situated in bedrock which is rich in iron and calcium. Contains lower lever of contaminants and organic material because it is filtered as it passes through the earths layers.
An aquifer
Is an underground layer of water-bearing, permeable rock, rock fractures, or unconsolidated materials (gravel, sand l, or silt)
Municipal water (treated water)
Surface water and/or ground water that is treated at a municipal treatment works before being supplied to the brewery.
Produce water
Interacts with the product
Process water
Assists in ttyhe functioning of various production processes
Service water
Provides water to non-production (service) systems
Filtration (screening)
Filter through metal grills/ screens to filter out larger or smaller particles, depending on the mesh size
Filtration (coagulation and sedimentation)
Chemical coagulants, such as aluminium or ferric chloride, reduce time for solids to coagulate or flocculate out
Sand filtration
Remove turbidity, algae, and microorganisms.
Cartridge filtration
Polymer fibres wound into a spiral that traps particles. Used for water with low levels of suspended solids.
Membrane filtration
Semi permeable membrane
1. Microfiltration
2. Untrafiltration
3. Nanofiltration
4. Reverse osmosis
Microfiltration
Removed Down to 0.1um
- yeast, solids, colloids, most bacteria
Untrafiltration
Removed particles down to 0.01um
- viruses, colloids, large organic compounds (such as proteins)
Nanofiltration
Removes particles down to roughly 0.001 um
-removes organic compounds including trihalomethanes, THM and some salts
Reverse osmosis
Removes particles down to 0.0001um
- removed most dissolved ions and molecules
Carbon filtration
Removes free chlorine and most organic contaminants.
- organic halogenated compounds can affect colour and taint flavour and aroma
Free chlorine
Often added to municipal water to make it safe to drink.
Halogen compounds (such as chlorine, fluorine, bromine, and iodine) combine with organic material to produce organic halogenated compounds such as trihalomethanes (THMs) and chlorophenols. These compounds can colour the beer and produce taste or odour taints.
Sterilisation, chlorine dioxide
Kills microbial cells by oxidising them. Unlike free chlorine does not produce flavour taints, non corrosive, and non toxic.