Transcript Chemical Engineering III
Clean Water: Is There a Solution?
Chemical Engineering III
Defining the Scope of the Problem
Introduction
• Problems with Unsafe Water – Lack of sanitation kills more people than all forms of violence, including war – Worldwide, children in rural areas that don’t have clean water are especially affected because their bodies aren’t strong enough to fight illnesses • 90% of the 30,000 deaths that occur every week from unsafe water and unhygienic living conditions are of children under five years old
Shortage of Water
• • People in rural communities often need to walk for miles every day to the nearest water source – Time spent walking and the resulting diseases keep them from work, school, and taking care of their families In developing countries, dehydration from illness and lack of water accounts for about 2 million deaths per year
Group Research
Possible Solutions
Solution 1: Treatment System
• 5 step water treatment system – Coagulation – Sedimentation – Filtration – Disinfection – Corrosion Control
Step 1: Coagulation
• • • Water from reservoir drawn into large basins at treatment plant Alum, lime, CO 2 , water and polymer added to the These chemicals cause small particles in water to coagulate and form larger particles
Steps: 2 and 3
• • Sedimentation – Large particles fall to bottom of basin where they are removed Filtration – Water is pushed through small particles such as sand and coal – This removes smaller particles from the water
Steps: 4 and 5
• • Disinfection – Disinfectant added to the water to protect against viruses and bacteria that may be present Corrosion Control – pH is balanced by alkaline metals to control corrosion of plumbing in city, businesses and homes
Strengths and Weaknesses
• •
Strengths
It has been proven to work over many years.
Take into consideration pH and the plumbing of the city • •
Weaknesses
Very archaic way of treating water Microbes can easily pass through Sedimentation and filtration
Solution 2: Boiling
• • Heat the contaminated water until the water reaches a point where the microbes in the water are killed by the heat Most microbes are killed under 100⁰ C, however boiling the water also removes many gasses from the water
Pros & Cons
• •
Strengths
Simple and cheap process Can be done practically anywhere • • • •
Weaknesses
Longer boiling time required when altitude is over sea level by 5000 feet “Hard water” causes calcium deposits on equipment Boiled water stored for long periods of time grows bacteria again Lacks sustainability
Solution 3: Reverse Osmosis (RO)
• Reverse Osmosis – Semi-permeable membrane created to filter water through.
– An impure solution is pushed through the membrane and pure water comes out.
– Like filtration method but more thorough.
Strengths and Weaknesses
• •
Strengths
Most effective for large scale purifying Easy to create the membrane used for this method • • •
Weaknesses
Without proper care the membrane can become easily clogged with algae and bacteria Membrane can easily rip or break Most expensive
Proposed Solution
Our Solution
• • We will be using proposed solution number 1, the Five Step Water Treatment System This process consists of Coagulation, Sedimentation, Filtration, Disinfection, and Corrosion Control
Process Diagram
Why We Chose This Solution
• • • We chose this solution because it has been proven to work over many years This solution also takes into consideration pH and the plumbing of the city, so it can be customized to work best for the situation it is being used in The process is sufficiently sustainable (discussed next slide) and cost effective
Is This Process Sustainable?
• Chlorine and other chemicals used to disinfect the water can corrode pipes and taint the water – Therefore, stainless steel pipes will be used in order to limit this – Equipment always has a functional life and will eventually need to be replaced
Applicability
• • This process is already in place for most large scale water purification operations We will stress the importance of stainless steel piping to limit water impurities
Conclusion
• • • • Water is becoming increasingly polluted and fresh water is becoming more scarce. As poor countries have difficulty finding clean water, alternatives developed to unsure humanity has safe water to drink.
These alternatives include water treatment system, boiling, and reverse osmosis. Each way is effective and can help reduce world thirst for years to come.
Conclusion
• • • With the Better Place Project, we applied our engineering curriculum to a global problem We wrote this PowerPoint similar in a lab report format in order to develop our technical writing skills This solution is a viable option that is both cost effective and sustainable
Questions?
• Please ask us any questions at the GBC ceremony!
Student Reflections
Student Reflections
• “I learned that it is important to make sure everyone's voice is heard. Each member of the group is valuable and their opinion and wisdom is needed to make the best project.” Lauren Lamping • Through our Better Place Project, I learned there is "a need, a need for clean water." I also learned we need to give people in need "water they can't refuse." With our research, we found that people can "say hello, to a little clean water!“ Blake Boswell • “I enjoyed the time we spent working in a group. I liked the discussions we held and how everyone did their part in creating our project. Everyone put forth ideas on what our project could be and it showed that we were interested in our field. It was great working with people who have the same career goals in life.” Melissa Kohne
• “While working on the better place project with my learning community, I learned how fortunate we are to have constant access to clean water. I had no idea how much of our population suffers or die because of lack of sanitary water. After researching and seeing the data, it opened my eyes to a large issue within our world that I hope to one day, as a chemical engineer, help to find a new and more efficient solution.” Kelly Louie • “Really, the most significant part of the entire program was just making a few good friends. That’s what I took away, for the most part.” Saif Aijaz • “What I got out of this experience was a group of people who I could go to for homework help and study sessions. I am grateful for that.” Jason Hughes