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SDG:#6

Ensure availability and sustainable management of water and sanitation for all

Connected to Big Ideas: C1, E1

Chloramine treatment facility (City of Markham, n.d)

BACKGROUND INFORMATION: 

Chloramination is a process that has been used for over a century and is also the disinfection process used by the City of Toronto. Dr John Leal created the process in 1908, which led to a rapid decrease in deaths from waterborne diseases. Unlike chlorination, chloramination adds chlorine and small amounts of ammonia to water during the treatment process to form chloramine, a disinfectant. This kills microorganisms such as viruses, bacteria, and algae and leaves behind disinfected water (City of Markham, 2020).

Chloramination is used by the City of Toronto (where Markham gets their water from) because it is more effective and lasts longer in the distribution system. When the water travels from Toronto to Markham, it is more resistant to any contamination (City of Markham, n.d).

Chloramination utilizes a double displacement (acid-base) reaction where NH3 is a base and HOCl is the acid and they react to form chloramine and water.

IMPACT ON HUMAN HEALTH AND ENVIRONMENT: 

SDG: #6

Ensure availability and sustainable management of water and sanitation for all

Connected to Big Ideas: C1, E1

(Turner et al., 2019)

BACKGROUND INFORMATION:

Coagulation is a process used by the City of Toronto and many other water treatment systems. A coagulant, usually a heavy metal, is added to water coming out of intake pipes to separate microscopic suspended solids.

Suspended solids are usually negative as the phosphate group has a larger partial negative charge. Thus, the coagulant has a positive charge to neutralize the suspended solids. ‘Spongy’ sludge pieces that can be separated from the water more easily are created (City of Markham, 2020).

Some common coagulants are aluminum sulfate, ferric sulfate, and ferric chloride (Hancock, 2018). Here is one example reaction for coagulation with aluminum sulfate, highlighted is the ‘suspended solids’ intended to be coagulated:

Word equation: aluminum sulfate + calcium bicarbonate → aluminum hydroxide + calcium sulfate + carbon dioxide

IMPACT ON ENVIRONMENT/HUMAN HEALTH:

SDG: #11

Make cities and human settlements inclusive, safe, resilient, and sustainable

Connected to Big Ideas: C1, F1

(Edmond, 2017)

IMPACT ON ENVIRONMENT/HUMAN HEALTH:

Planting of trees has been known to be able to cut urban air pollution. Not only do trees absorb carbon dioxide from the air, trees also improve the sustainability of cities and human settlements by shading buildings and reducing the need for air conditioning. This means less fossil fuel consumption as trees can cool the air between 2-8 degrees Celsius, reducing the need for cooling (Kinver, 2016).

BACKGROUND INFORMATION:

Using the energy of the sun, trees absorb carbon dioxide and water to convert into chemical compounds (ex. Sugars that feed the tree). The by-product of the endothermic chemical reaction is oxygen. In addition, trees store carbon dioxide in their fibers (Stancil, 2019).

IMPACT ON ENVIRONMENT: 

SDG: #11

Make cities and human settlements inclusive, safe, resilient, and sustainable

Connected to Big Ideas: C1, F1

(USDE, n.d)

BACKGROUND INFORMATION: 

Hydrogen fuel cells are an invention used by the space industry. In space, hydrogen and oxygen gas are burnt so water is created as a by-product astronauts can drink.

FIRST CANADIAN CONNECTION:

Companies like Ballard Power Systems Inc. located in Vancouver, BC are working to use fuel cells for automobiles. (An example of making cities more sustainable through innovation in transportation) (Clancy, 2011)

Fuel cells utilize a double displacement reaction between coal or a hydrocarbon and water to produce the hydrogen gas needed and carbon dioxide. In this balanced equation, I will be using methane (CH4) as an example.

ENVIRONMENTAL IMPACT:

Although fuel cells themselves are non-polluting because water is the only product (BBC, 2020), creating the hydrogen gas needed creates a lot of CO2 pollution. CO2 affects the environment negatively by contributing to the greenhouse effect, climate change, and acid rain (Rogers, 2018).

SDG: #12

Ensure sustainable consumption and production patterns

Connected to Big Ideas: B1, C1, F1

“The Antarctic hole is stabilizing and may be slowly recovering.” (NASA, n.d)

BACKGROUND INFORMATION:

In the 1970’s, the detrimental effects of chlorofluorocarbons (CFCs) began to surface. Up in the atmosphere, CFCs would break apart into chlorine atoms after exposure to high levels of UV radiation and destroy ozone molecules (Clancy, 2011).

Afterwards, the following reactions occur:

(chlorine reacts with ozone to form chlorine monoxide and oxygen)

(The product of the previous reaction, chlorine monoxide, reacts with another molecule of oxygen, releasing chlorine that can further ‘destroy’ ozone molecules) (Brenna & Bressa., 2015)

ENVIRONMENTAL IMPACT: 

The cycle of chlorine atoms destroying ozone molecules continues. One chlorine atom can destroy thousands of ozone molecules, resulting in the depletion of the ozone layer. Although CFCs aren’t the only contributing substances, they are the most abundant. As the hole in the ozone layer increases, more UV radiation can reach the earth. This increases the risks of skin cancer (EPA, 2018) and negatively affects atmospheric circulation (NASA, n.d).

Second CANADIAN CONNECTION:

INSIGHT: From this project, I learned more about the scope of chemical processes around us and how they can have an incredible positive impact or affect us and the environment negatively. From CFCs to chloramination to synthetic polymers, chemical innovation is all around us. I also learned that products, items, and innovations don’t necessarily have a positive or negative impact, it’s not an either or. Meaning, there are considerations that have to be made with any choice involving our health and the environment. For example, coagulation helps ensure the safety of our drinking water but at the cost of producing high volumes of hazardous sludge. Lastly, I learned that although we aren’t behind the chemical processes and cannot work to make them sustainable (for now), we can control our consumption of certain products like single-use plastics.

OPINION ON SDGs: In terms of SDGs, I believe that a world where the SDGs are realized will provide a valuable and happy life for future generations, for our grandchildren, great-grandchildren, and beyond. When all SDGs are fulfilled, I believe the world would be a place of equity and environmental calm. But first, action must be taken, starting with ourselves.