pure water. unit map set up unit name: water purification and wastewater treatment unit essential...
TRANSCRIPT
Pure Water
Unit Map Set Up
Unit Name: Water Purification and Wastewater treatment
Unit Essential Question: Why is it important to purify and treat water?
Unit Map Set UpLesson essential questions and vocab (as we go)
Lesson Essential QuestionWhy must water be purified?
ObjectivesUnderstand that water is not pure
Understand why water is not pure
“Pure” waterWhat do you think of when you hear this?
Let’s test this.
Pure WaterWater is never pure in nature
Most effective of all natural solvents
Examples: Sugar Water, Coca Cola
Pure WaterWater holds substances in suspension
Fast moving- holds large particles
Slow moving- holds smaller particles
VocabSolution- molecules of one substance dissipated among the molecules of another substance
Suspension- solid particles held temporarily or permanently in a liquid
Solvent- substances that dissolve other substances
Exit Question What did you see in your water?
Water Processing
Warm-upWhat is a solution? Give an example.
Lesson Essential QuestionHow is water processed?
ObjectivesDiscuss how water is processed
Processing WaterTreated depending on where it comes from
Clean groundwater needs little pre treatment
Processing WaterMunicipal reservoir water, upland streams, and lakes with limited inflow need minimal treatment
Processing WaterWater from rivers with industrial agriculture and municipal wastes needs extensive treatment
Treatment Systems2 types in use
Individual Household systemsSeptic treatment systems
Large-scale wastewater treatment systemsVary based on nature and size
ActivityPollution travel map
Exit QuestionWhy is it important to understand what is in our water?
Water Impurities
Warm-upWhat is this?
Lesson Essential QuestionWhat are some chemical water impurities?
ObjectivesOutline impurities that must be removed from water for use by humans.
Water Impurities 3 categoriesChemicalBiologicalturbidity
Chemical Impurities Can result in 1 of 3 conditionsWater that is dangerous to drink
Undesirable color or smellToo acidic or alkaline
Chemical Impurities To be used for human consumption, water pH should be near 7.0
Minerals, metals and salts are almost always present in clear water
Chemical Impurities Distilled water is close to pure, but contains impurities
Low levels of dissolved minerals and metals is healthy for people
Chemical Impurities When concentrations get high, water no longer good and becomes detrimental to human health
Chemical Impurities Water from ground supplies contains dissolved iron or manganese Forms rust when exposed to oxygenToilet bowls, sinks, plumbing fixtures
Chemical Impurities Hard water-result of excess calcium or magnesium, form scale deposits that clog up pipes and plumbing Make soap less effectiveTastes badTreated with “softening” agents
Chemical Impurities Sulfur content in water
Sulfur dioxide- rotten egg smell
Yellows clothes if washed
Chemical Impurities Dissolved nitrogen and phosphorusCommon fertilizers, water-soluble
Promote algae growthCause serious health problems
Chemical Impurities Dissolved hydrocarbonsDisolved methane, methanol, and various alcohols
Tannin- hydrocarbon from decaying organic matter
Excess chlorine- bad tasteExcess fluorine- discolorations on teeth
Chemical Impurities Testing for Pesticide Concentrations Lab
Turn in Questions at the end of class
Vocab Hard water- a result of excess calcium or magnesium
Water Impurities
Warm-up
How is hard water treated?
Lesson Essential QuestionWhat are some biological impurities in water?
ObjectivesOutline impurities that must be removed from water for use by humans.
Biological ImpuritiesRange from mammals to viruses and from aquatic trees to algae
In water treatment, fish, crustaceans, worms, and macro-invertebrate are removed at the beginning by screening
Biological ImpuritiesLarger plants and plant parts are also removed by screening
Small plants, including algae are not completely removed by screening, they require treatment
Biological ImpuritiesAlgae
Tiny green plants that grow in sunlight and air
Generally harmless but can remove oxygen from water that will kill fish
Biological ImpuritiesBacteria and Fungi
Serve as decomposers and help break down organic matter and chemicals into harmless compounds
Biological ImpuritiesBacteria and Fungi
Can be dangerous as pathogens (disease causing organisms)Typhoid fever and cholera
Biological ImpuritiesBacteria and Fungi
Protozoa- single-celled animals that occur naturally in all healthy water supplies
Biological ImpuritiesBacteria and Fungi
Certain protozoa pathogenicDiarrhea and dysentery (inflammation of intestine that causes diarrhea- fatal)
Helmiths- microscopic wormlike organisms that can infest the intestinal tract causing illness.
TurbiditySolid matter suspended in liquid
Naturally solid matter held in suspension
Visible concentration= aesthetically unpleasing
Removal important step for human use
VocabMacroinvertebrate- organisms that do not have a backbone and are visible without a microscope.
Algae- tiny green plants that grow in sunlight and air
VocabProtozoa- single-celled animals that occur naturally in healthy water supplies
Helmiths- microscopic wormlike organisms that can infest the intestinal tract causing illness
Water Treatment
Warm-upHow do we treat wastewater?
Lesson Essential QuestionHow are different types of water treated to be safe for human consumption?
ObjectivesList and describe kinds of wastewater generated
Describe how septic systems are designed and how they work
Discuss how wastewater is treated before it is returned to the water
Water TreatmentObjective- produce potable water supply
Majority of water must be purified before it is safe for human consumption
Well WaterGenerally safe Test periodically for biological or chemical contaminants
May contain undesirable levels of iron, manganese, or sulfur, excess calcium or magnesium
Well WaterTreatment systems from commercial sources to remove metals and minerals
Water softeners availableCommercial iron and sulfur removal systems and activated charcoal filter systems for household use
Municipal Water Treatment PlantsVary depending on size of the community and nature of the water source
influent- water moving into a treatment system
Effluent- water that comes out the other end of the system and is ready for use
Municipal Water Treatment PlantsTypical Plan
Figure 15.5
VocabPotable water- water that is chemically and microbiologically safe and that is otherwise suitable for human consumption
VocabInfluent- water moving into a treatment system
Effluent- water that comes out the other end of the system and is ready for use
VocabCoagulation- physical process of smaller particles clumping together to form larger particles that will later be allowed to settle out of the water
VocabFlocculation- process of stirring together influent with coagulants or other additives that assist in the water purification process
Flocculator – large tank where paddles stir the water to induce clumping
Exit Question
What type of system does your family have? Do you do anything extra to make sure the water that you are drinking is pure?
Water Treatment
Warm-up
List the steps in a municipal water treatment plant.
Lesson Essential QuestionHow is water processed through a municipal water treatment system?
ObjectivesList and describe kinds of wastewater generated
Describe how septic systems are designed and how they work
Discuss how wastewater is treated before it is returned to the water
Municipal Wastewater Treatment3 phases
Primary waste treatment
Secondary waste treatment
Tertiary waste treatment
Primary Waste TreatmentMechanical system that collects the wastewater and removes the items that settle from it
Includes a screening device, grit chamber, settling tank, sludge digester, and drying beds
Primary Waste TreatmentRemoves 2/3 of wastes from water
Grit chamber- wastes ground into finer particles to speed up the decomposition
Primary Waste TreatmentWastes then settle into the sedimentation tank
Wastes removed and placed into sludge digester
Secondary Waste TreatmentBiological processing of sewage
½ of all city plants contain this system
Extension of the primary system
Secondary Waste TreatmentPiped through aeration tank to increase oxygen contentAerobic bacteria increase, increases efficiency of treatment
Water then pumped into sedimentation tank for settling
Remaining water discharged after treated with chlorine
Secondary Waste TreatmentSludge sent through aeration tank to allow decomposition
Removes 90% of organic wastes
Chemical compounds (nitrates, phosphates) remain and require more treatment
Tertiary Waste TreatmentChemical processing of sewage wastewater
Removes nitrates and phosphates
More costly Used only when water is being reused
Tertiary Waste TreatmentAdd lime to remove phosphates
Stripping tower to remove nitrates
VocabStripping tower- vertical tank through which the water moves slowly while the lime and water are in contact, allowing the chemical reaction that removes the excess nitrates.
VocabGrit chamber- wastes ground into finer particles to speed up the decomposition
Water Conservation
Warm-upWhat can we do to conserve water?
Lesson Essential QuestionHow can water be preserved?
Water ConservationShould reserve top quality water for drinkingUse lesser quality for washing cars, flushing toilets, and water our lawns
Water ConservationRecycle ALL water, even sewage water
Federal government placing tighter pollution standards on industrial water supplies=forces them to reuse water over and over.
Test ReviewWorksheet