Water Conservation and
Water Pollution Control:
Water
Magister Teknik Pengendalian Pencemaran Industrial
Department of Chemical Engineering
Faculty of Engineering
ugm.ac.id L O C A L LY R O O T E D , G L O B A L LY R E S P E C T E D
Introduction to the Lecture
Sources of water and getting to know it
Water Resources
There are 2 main types of water in the world: In more detail:
2.06% 0.90%
0.01%
0.03%
Salt water (97%) Fresh water (3%)
97.00%
Saline water Icecaps and glaciers Ground water
Lakes Swamps Rivers
Others
Water Use
Those 3% of all water are used in many things, such as foods: And, in many other chemical products:
15.415 L per kg 21.000 L per kg 4,99 L per kg
3.265 L per kg 4.325 L per kg 1,31 L per kg
700 L per kg 1.500 L per kg 949,94 L per kg
Problems Relating to Water in Indonesia
(Based on Peraturan Presiden No. 37 Tahun 2023)
Degradation of river flows. Conflicts relating to water uses.
Limited knowledge and self-
Excessive use of ground water.
awareness from the society.
Excessive land transform. Overlapping of water resource
management.
Lack of supporting facility. Lack of data and accurate
information.
Challenges Relating to Water in Indonesia
(Based on Peraturan Presiden No. 37 Tahun 2023)
Implementation of technology
Variety of rainfall.
relating to water.
Population growth. Water security.
Fulfillment of SDGs. Climate change.
SDGs Target and National Mid-term Plan
Relating to Water in Indonesia
(Based on Peraturan Presiden No. 37 Tahun 2023)
Accessible drinking water to all. Sustainable water supply.
Implementation of integrated
Accessible sanitation to all.
water resource management.
Higher quality water. Protection and recovering
water resource ecosystem.
Efficient water use on all sectors. Lowering the risk of water-
related disaster.
Getting to Know Your Water
Almost all substance can be dissolved by water, that is why most water are impure.
There are 4 types of water impurities:
Physical Dissolved Microbial Radiological
Color, taste, odor, and appearance. Cations, anions, metals, gasses. Bacteria, viruses, protozoa, etc. Radium, uranium, etc.
Solubility
From the previous types of water impurities, the main
principle that factor it all is solubility.
Solubility is influenced by many things; can you guess it?
If things are not
soluble in water, then
water is pure of it.
Substance in Water: pH
Water or H2O automatically ionize into H+ and OH-. The concentration of these ions are
10-7 M at room temperature. As pH is calculated by using the following equation:
𝑝𝑝𝑝𝑝 = − log 𝐻𝐻 +
A typical pure water pH is 7 (or neutral).
Essentially, pH is a way for human to base their world on the most
prolific solvent: water. Solution with pH that is lower than 7
considered as acidic and above 7 considered as basic.
Most common things that Most common things that
happens due to low pH is: happens due to high pH is:
pH does not
have any bound, it
can go beyond 0 or
14.
Substance in Water: Dissolved Gases (ppm)
Carbon Dioxide (CO2) Oxygen (O2)
• CO2 is 30 times more water soluble than O2. • Basically, what makes things live in the water.
• CO2 will form carbonic acid in water and lower • Also, the main factor of corrosion.
the pH. Ammonia (NH3)
𝐶𝐶𝑂𝑂2 + 𝐻𝐻2 𝑂𝑂 ⇌ 𝐻𝐻2 𝐶𝐶𝑂𝑂3 ⇌ 𝐻𝐻 + + 𝐻𝐻𝐻𝐻𝑂𝑂3 − • At low pH, found in form of NH4+.
• Highly alkaline water able • The presence of ammonia in water indicates
to resist pH change and the presence of microorganism.
desirable in preventing • Accelerate corrosion in metals.
corrosion of industrial Hydrogen Sulfide (H2S)
equipment. • Is a highly toxic gas that could kill things.
• CO2 also influence the alkalinity of water, which • Basically, the thing that you emit from your
the ability of water to sustain its pH (buffering read end.
capacity).
Substance in Water: Dissolved Ions
Dissolved Ions and Conductivity (μS/m)
• Ions in water enhance the ability of water to conduct electricity.
• High conductivity indicates higher amount of ion content.
• Another parameter that also correlates well with conductivity is Total
Dissolved Solids (TDS).
Hardness (mg CaCO3/L)
• Calcium and Magnesium ions are things that make water hard.
• Most Calcium and Magnesium salts do not have high solubility in water, when
the solubility limit achieved, Calcium and Magnesium salt precipitate.
• Due to low solubility of Calcium and Magnesium salts, it can form scale in
industrial equipment and decrease its heat transfer ability.
Substance in Water: Organics
Biochemical Oxygen Demand (BOD)
• The amount of oxygen in mg/L that needed by
microorganism to consume biodegradable organics
in water under anaerobic conditions over 5 days
period.
Chemical Oxygen Demand (COD)
• Total organic content that can be oxidized by
potassium dichromate in sulfuric acid solution.
• COD is faster to measure since it only needs 3 hours
rather than BOD which needs 5 days to complete.
Substance in Water: Physical Appearances
Turbidity
• A way to indirectly measure suspended solids in water.
• Suspended solids contributes to fouling and potentially
harbor microorganisms which may cause corrosion.
Color
• Influenced by decaying organic matter, i.e.
tannins, lignin, iron, or manganese salts.
Substance in Water: Others
Heavy Metals Microorganisms
Chromium • Viruses • Algae
• Used for plating, dyes, etc. • Bacteria • Helminths
• Cr6+ is toxic to human and potentially cause death. • Protozoa • Fungi
Cadmium
• Used for battery, electronics, etc.
• Cd is carcinogens.
Radionuclides
Lead
• Used for battery, ammo, etc.
• Harm all human organs.
Mercury
• Used for Chlorine gas and Caustic Soda.
• Harm your brain!
Let’s discuss what we have learned today!
L O C A L LY R O O T E D , G L O B A L LY R E S P E C T E D
ugm.ac.id
