Microalgae Utilization for Removal of Organic Compounds from Wastewater: Circular Economy Concept
Patricia Akao, BMI Fellow
Academic Advisors: Prof. Dror Avisar and Prof. Hadas Mamane
Treated wastewater can be an alternative source for depleting water sources for crop irrigation, however conventional wastewater treatment plants are energy intensive and costly to construct and operate, especially for low-middle income countries. The present study focused on improving the quality of wastewater by incorporating coupled microalgae-bacteria biofilm (CMBB) treatment to the wastewater ponds. Standard polyether sponges were dipped in the raw wastewater samples to enhance biofilm development on the sponges. The enriched sponges were used to treat wastewater, with or without external energy for aeration. Wastewater parameters were analyzed during the enrichment and treatment processes. The CMBB technology improved effluent quality at similar levels to aeration, however saving the energy costs, reducing 36% of chemical oxygen demand (CODt) within 24 hours and 71% within 4 days. The values of biochemical oxygen demand (BOD), ammonium and phosphates reduced by 80%, 64% and 95% within 7 days, respectively. The values for COD and BOD obtained were below the maximum allowed for reuse and discharge.”
Following the improvement that was obtained using coupled microalgae-bacteria biofilm (CMBB) to improve wastewater parameters, the capability of the CMBB to remove recalcitrant pharmaceuticals from wastewater was tested. Four pharmaceuticals were chosen (sulfamethoxazole, venlafaxine, carbamazepine and iohexol) and tested by the ability of the consortia to remove these compounds. Also, it was decided to characterize the biofilm, identifying what types of bacteria and microalgae are present at the biofilm and to understand their role at the removal. Three concentrations of CMBB were chosen (20, 40 and 80 milliliters of wastewater per sponge) and light and dark conditions were tested (L and D). No removal of iohexol was seen after 5 days, on dark and light conditions. For venlafaxine, during the first day it was possible to see 82% removal at L-CMBB-20, 62% removal for L-CMBB-40 and 36% removal for L-CMBBB-80, after5 days the removal reached 90% for L-CMBB 40 and 20. In the dark, 24% of venlafaxine were removed and kept steady until day 5. Carbamazepine removal reached 43 to 50% between 1-5 days for L-CMBB-20, and oscillated between 2 -36% between LCMBB-40 and 80 during these 5 days. The results obtained for sulfamethoxazole were inconclusive.
Patricia is currently at the final stages of writing her Ph.D. dissertation and we are very proud of being a part of her progress.
Evaluation and examination of the geopolitical and social structure for implementing water technologies in developing societies in Sub-Saharan Africa
Ariel Aviram, BMI Fellow
Academic advisor: Prof. Dror Avisar
Worldwide water crisis is a severe issue that humanity is facing throughout this century. This water governance caused by the combined effects of population growth and demographic changes, aside with climate change, water source contamination, depletion, and the ways we mismanage water. Access to safe water and proper sanitary conditions are essential variables that give the population the physical and mental capacity to develop outside the vicious and endless cycle of life in poverty. Technological interventions such as access to water for a remote village are expected to improve living conditions for the community members, but also to abolish old traditions and customs and create a dramatic change in the familiar and safe social and political local environment. Very rarely, do the two disciplines of culture and technology merge their methods in a mutual research project to achieve a real well-adopted, and sustainable change.
The focus of this research is to figure out the appropriate ways to circumvent geopolitical, cultural, and social barriers, in order to find the right ways of Implementing water treatment. For the first year, the field study will be conducted in Tanzania in collaboration with Innovation Africa (IA). During the field study, the way how water drilling projects affect African societies will be examined, as well as whether the interventions that were done by IA encountered some barriers. This field study has a unique contribution to this research as it gives the opportunity to investigate the communities along a process of technology implementation. The study will also explore whether social, cultural, or geopolitical barriers affect the project implementation and success.
Real-time, Low-cost Nitrate Detection in Wastewater
Michale Goldenberg, BMI Fellow
Academic Advisors: Prof. Dror Avisar and Prof. Hadas Mamane
The research is focused on developing a simple, inexpensive electrochemical sensor for the detection of nitrates in water through the use of voltammetry. The sensor will measure the ionic content of the water, and interface with the internet to send information about contamination to consumers. By monitoring their water, consumers can prevent consumption of polluted water, as well as determine their need for a more complex purification system. Various voltammetry methods were compared, including cyclic voltammetry and square wave voltammetry. Both techniques provide a simple, linear relationship between concentration and current. By looking at the differences in the current peaks at different concentrations, it is clear that square wave voltammetry far outperforms cyclic voltammetry in its ability to sense changes in nitrate concentration.
Water Research in India - Developing Water Quality Survey Tool
Selda Edris, BMI Fellow
Academic Advisor: Prof. Hadas Mamane
The subject and field of the research remained the same: wastewater. The researcher has joined an existing study on developing sustainable carriers to streamline sewage treatment processes in India. In the study, the aim is to try to arrive at a structure and material suitable for use in this field. Selda’s role in research is to lead the field of experiments in this study. The research team had recently made connections with sewage treatment facilities to carry out the field experiments. Selda is in charge of the preparatory work for the experiment, such as calibration and ordering equipment. Currently, two trials are being planned within the MTAs to test the feasibility of the various carriers.
Water research in India, continued in Israel: Fecal Coliforms Presence Nowcasting Using Deep Neural Networks
Asaf Pras, BMI Fellow
Academic Advisor: Prof. Hadas Mamane
At least 2 billion people worldwide use drinking water sources that are contaminated with feces, causing waterborne diseases; poor sanitation, poor hygiene, and unsafe drinking water result in a daily death rate of more than 800 children under 5 years of age from diarrheal diseases. This study shows the feasibility of a novel method to cast the presence of fecal coliforms (FC) in drinking water sources by applying a multilayer perceptron artificial neuron network (MLP-ANN) model. The model gives a binary answer for FC presence or absence in raw water, using a few water quality and geographical parameters, which can be monitored in real time as predictors with low-cost equipment. Using 62,000 samples to train, validate and test the model, a total accuracy of 84.56% was obtained using temperature, pH, electrical conductivity, turbidity, dissolved oxygen, and biological oxygen demand (BOD) as water-quality inputs and the water source and location (states in India) as geographical inputs; sensitivity reached 93.63%, meaning that most of the FC-contaminated samples were classified correctly. Using the model without BOD changed the accuracy and sensitivity slightly, to 84.43% and 93.70%, respectively. Thus, low-cost monitoring of inputs in real time is possible. Results show that the MLP-ANN model can be used as a tool for bacterial monitoring and management in water, reducing the need for time-consuming or expensive tests.
Removal of Micro-Pollutants from Hospital Wastewater
Adi Zilberman, BMI Fellow
Academic Advisors: Prof. Dror Avisar, Prof. Hadas Mamane and Yaal Lester, Environmental Engineering, Azrieli College, Jerusalem
Hospital wastewater are one of the point sources of various micro-organic persistent and toxic contaminants, secreted by the hospitalized patients. Treated wastewater (effluent) become an alternative water resource under the global water scarcity problem. In Israel, about 85% of the effluent water are allocated for agricultural irrigation and the rest goes into the sea or rivers and even for insertion into aquifers. Pharmaceutical residues are part of a group of persistent and toxic micro-organic contaminants that flows into the water-treatment plants from hospitals, industry, agriculture and domestic sector. These contaminants are resistant to conventional biological treatment used as a secondary treatment. As a result, those contaminants can still be found in the effluent that runs into rivers, and used in agriculture. In this study, we treat the pharmaceutical residues in the source, In that way, we decrease their concentration in the effluent and by that contribute to food security and environmental sustainability.
The Boris Mints Institute Water Lab deals with the contemporary global challenges of water shortage and water quality through rigorous and groundbreaking research.
Professor Hadas Mamane (BMI Water lab) together with Dr. Vered Blass recently won a 230,000 euro grant to fund new research.