The efficacy of the Ceramic Water Purifier for rural Sierra Leone

Transcription

1 The efficacy of the Ceramic Water Purifier for rural Sierra Leone by Miriam Hansen MEng Chemical Engineering In collaboration with PhD candidate Ana Vieria and Dr. Blanca Andizar-Ladislao Acknowledgements

2 Outline 1. Motivation 2. Aims and Objectives i. Laboratory ii. Ceramic Water Purifier Design iii. Community Integration 3. Results and Discussion 4. Preliminary Conclusions 5. Further Work

3 Motivation 5,000 children die daily across the world due to unsanitary water (WHO, 2005). In Sierra Leone only 32% of the countries rural population have access to improved drinking water sources (UNICEF, 2004). Achieving water purification in developing countries is a fundamental human right which so far has failed to be achieved (UNICEF and WHO 2004). References WHO and UNICEF (2005) Water for life: making it happen. France, WHO and UNICEF. UNICEF (2004) Meeting the MDG Drinking Water and Sanitation Target: A Mid Term Assessment of Progress. Geneva: WHO. UNICEF(2004) At a glance: Sierra Leone.

4 The CWP Process Motivation The Ceramic Water Purifier (CWP) was designed by Dr. Fernando Mazariegos of the Central American Industrial Research Institute (ICAITI) in Guatemala, in Colloidal Ag coating Ceramic pores < 2μm

5 Motivation The CWP Process The Ceramic Water Purifier using a TiO2 coating. Incorporating low energy, low cost solutions with locally available resources. Contaminated Water Natural UV-visible radiation Colloidal TiO2 filter coating Colloidal Ag coating Ceramic pores 0.2μm < 2μm ceramic filter Potable Water

6 Motivation DNA damage Cell wall, DNA and protein damage Adapted from: Wu L, Khraisheh M, Antizar-Ladislao B (2008), Investigation of the use of doped-tio 2 to water disinfection and decontamination. Water and Sanitation in International Development and Disaster Relief, Proceedings of International Workshop, Edinburgh, 274

7 E.H,Schumacher, Small is Beautiful, USA1973 Motivation Development does not start with goods; it starts with people and their education, organisation and discipline E.H.Schumacher

8 Aim and Objectives AIM Aim To evaluate the potential of the CWP as a low cost, low energy water treatment solution which uses local skills and materials for sustainability in rural and peri-urban Sierra Leone. Objectives To investigate the ability of colloidal TiO2, a local resource in Sierra Leone to remove organic contaminants under natural conditions. To compare the ability of TiO2 and colloidal silver as filter pot coatings in their ability to remove organic contaminants and pathogens. To address the need of intermediate education and community participation to ensure sustainability.

9 Objective 1: Laboratory Method Collecting water from the River Almond Water collected from the River Almond. Samples places in brown jars and stored at 4 o C.

10 Objective 1: Laboratory Method The effect of TiO 2 /Ag on the removal of organic contaminants and pathogens in water in the presence of humic substances. Environmental conditions: Temperature, C ph, 7 Natural light and darkness. Humic substances: Leonardite 40 mg l -1 Organic contaminant Phenanthrene 0.8 mg l -1 Colloidal particles TiO 2, 10mg/l Silver, 1.5mg/l

11 Objective 1: Laboratory Method The efficacy of TiO 2 to remove PAH s River Water Ultra Pure Water Natural Light Darkness L3 X X L5 X X D3 X X D5 X X

12 Objective 1: Laboratory C/Co Method The efficacy of TiO 2 to remove Humic substances Time (hours) D4 D8 L4 L8 River Water Ultra Pure Water Natural Light Darkness L4 X X L8 X X D4 X X D8 X X

13 Objective 2: Ceramic Water Purifier Design Method The effect of TiO 2 /Ag on the removal of organic contaminants and pathogens in water in presence of humic substances, using CWP. Leonardite v Phenanthrene E.Coli TiO 2 Ag J=(1/A)*(dV/dt)

14 Objective 3: Community Integration Method

15 Objective 3: Community Integration Method

16 Objective 3: Community Integration Method Interactive Learning: Taking Science back to hands on E E E E E Engage Explore Explain Elaborate Evaluate Roger Meacham, Headmaster, Dalmeny Primary School, Edinburgh in conjunction with Primary Connections, Australia

17 Objective 3: Community Integration Results Results: Intermediate Education

18 Preliminary Conclusions TiO 2 is able to remove PAH s though the current time of 72 hours is too long a residence time for the CWP. Preliminary trials making the filter showed that the mould needs to be of a very rigid, yet still locally available material. Heavy stones could be fashioned to provide the weight required for pressing and can be simulated using concrete weights in the lab. Preliminary work has proved that it is possible to communicate the science and engineering principles behind the CWP making intermediate education at a community level viable.

19 Further Work Further Work To test the performance of TiO 2 as a ceramic filter coating in its ability to remove organic material and pathogens. To investigate the effect of doping TiO 2 in order to reduce the residence time of the CWP. To conduct field studies to investigate the appropriateness of the technology and technology integration potential in Sierra Leone.

20 Thank you for your attention Miriam Hansen School of Engineering The University of Edinburgh The Kings Buildings Edinburgh EH9 3JL, Scotland Institute for Materials and Processes & Institute for Infrastructure and Environment