Comparative Life Cycle Assessment of Direct and Indirect Solar Water Disinfection Processes in Developing Countries

In July 2010, the UN General Assembly recognized the universal human right to sufficient water for health and sanitation (UN…, 2010). The reliable disinfection of this water plays a critical role in public health (Carter and Miller, 2005), and this study investigates the use of four ultraviolet (UV) disinfection methods for use in international development and disaster relief. The study focuses on the life cycle impacts of four direct and indirect solar ultraviolet disinfection systems. Direct solar disinfection refers to exposure of water to solar radiation, while indirect solar disinfection collects solar energy and uses this to power a UV lamp disinfection reactor. These four systems were compared to chlorine disinfection and automobile distribution as baseline methods. Existing literature was used to define a life cycle functional unit for each system, which quantified the material use, infrastructure required, and life cycle of the components of each system. The impact of each system was then defined in the Life Cycle Analysis software SimaPro. Analyses compared the use of each technology at “community, school, small group, and family” scales. Due to the significant impact that end-of-use of a system can have on rural communities, an end-of-life analysis was conducted in addition to the quantitative life cycle analysis. Life cycle analysis shows that both direct and indirect UV disinfection methods vary dramatically over several categories of impact assessment. End of life analysis and this variation highlight the extremely complicated process of designing the appropriate disinfection system for use in developing countries

Recovery of Nutrients from Animal and Human Wastes

Removal of nitrogen- and phosphorus-containing molecules from wastewater is necessary to prevent excessive growth of algae and resulting chemical changes to bodies of water. Of wastewater components, urine contains relatively high concentrations of nitrogen and phosphorus, the majority of which is ultimately present as ammonia and phosphate. Separation and stabilization of these nutrients may also allow for their reuse as fertilizer. Before the nutrients may be stored, they must be stabilized. At least a portion of ammonia-N must be converted to nonvolatile nitrogen. This may be achieved by using ammonia- and nitrite-oxidizing bacteria (AOB and NOB, respectively) to convert ammonia to nitrate. Three fluidized bed reactors were developed to accomplish partial nitrification of human urine, swine urine, and supernatant from an anaerobic digester. AOB and NOB communities were established by incubation on Kaldnes K1 media in an ammonium chloride solution in a separate vessel. Ammonia concentration, pH, dissolved oxygen concentration, nitrate concentration, and nitrite concentration were measured to characterize the performance of each reactor. After replacing the ammonium chloride incubation solution with the three waste streams, detectable nitrification activity ceased. After diluting the feeds and shifting reactor pH to 7.5, no evidence of nitrification was found. Lack of nitrification after adjustments suggests decreases of AOB/NOB populations after application of the more concentrated waste streams. Development of a strategy to more gradually increase feed concentrations may be required for future work with similar reactors. Improvements to pH control will also be needed to accomplish effective startup of these reactors

Modeling Target Disinfection By-Product Dynamics in Indoor Swimming Pools

Chlorination is the primary disinfection method for swimming pools in the United States; however, chlorine also reacts with pollutants (e.g., sweat, urine and anthropogenic compounds) to form disinfection by-products (DBPs). Some DBPs are asthma causing (e.g. nitrogen-trichloride) and even carcinogens (e.g., trihalomethanes and nitrosamines). Consequently, exposure to DBPs poses health risks to patrons and staff in pool environments. Furthermore, volatilization of DBPs is enhanced by bather activity, but the relationship between activity and volatilization has yet been quantified such that the dynamic behavior of DBPs can be predicted. Therefore, the objective of this research is to clarify the relationship between bather activities and the behavior of DBPs quantitatively in order to simulate the liquid-phase transportation of target DBPs in indoor pools. An acoustic Doppler velocimeter will monitor the velocity of water over a period of time at various depths below the water surface to measure turbulence, which corresponds to bather activity. Concentration measurements of target DBPs will be taken parallel to the time and depth of the velocity readings, and then correlated to determine the turbulent diffusion coefficients of the target DBPs. The collected data will be used to construct a DBP transport model which predicts the concentration of target DBPs over time under inputted conditions. The result will give a quantitative relationship between physical activities of swimmers and transportation of target DBPs in indoor swimming pools

UV Water Disinfection Project Plan

15 slides Provider Notes:Submitted by Zorana Naunovi

Optimization of Physical and Chemical Disinfection Processes Subject to Extended Space Travel Constraints

30 slides Document Provider Notes: Seminar Title: Optimization of Physical and Chemical Disinfection Processes Subject to Extended Space Travel Constraints; Date: 11/01/2002; Time: 9:00 AM; Location: Food Science; Comments: Video will be available

ALS Technology Questionnaire--Water Disinfection (UV and iodine) Summary

5 pages Provider Notes:This page contains the data collected to date. 06/25/03 Data from interview at NSCORT workshop. 09/23/05 Initial Meeting with Jim Russell, Mike Lasinski, Zorana Naunovic and Ernest Blatchley. 09/26/05 Questionnaire 1-6 (Water Disinfection_20050926.doc). 10/19/05 Updated ESM calculation done by Zorana. 10/21/05 Questionnaire Completed (Water Disinfection_Questionaire_02.doc). To Be Completed: Chip and Zorana, please complete the questionnaire (Questionnaire_20060504.doc in your directory). The instructions are on the first page of the document, and this questionnaire updates and builds on the previous survey. To create feasible scenarios for a human mission to Mars, we need to understand the Equivalent System Mass (ESM) and interactions of the technologies involved. The purpose of this specification sheet is to provide data about technologies being developed by ALS NSCORT; the data will be in an Excel repository. The answers will be used initially in the September 30th center meeting and later for the November 15th review by NASA. Related Documents:WSR17a, WSR17c, WSR17d, WSR17e, WSR17

Liquid Phase/UV/Iodine (Water Disinfection)

3 pages Provider Notes:This page contains the data collected to date. 06/25/03 Data from interview at NSCORT workshop. 09/23/05 Initial Meeting with Jim Russell, Mike Lasinski, Zorana Naunovic and Ernest Blatchley. 09/26/05 Questionnaire 1-6 (Water Disinfection_20050926.doc). 10/19/05 Updated ESM calculation done by Zorana. 10/21/05 Questionnaire Completed (Water Disinfection_Questionnaire_02.doc). To Be Completed: Chip and Zorana, please complete the questionnaire (Questionnaire_20060504.doc in your directory). The instructions are on the first page of the document, and this questionnaire updates and builds on the previous survey. Related Documents:WSR17a, WSR17b, WSR17c, WSR17d, WSR17

Photochemical Kinetics of the Iodide/Iodate Actinometer and Iodine Dose-Response for B. Subtilis Spores --EAC Presentation 2004

As part of the NASA Specialized Center of Research and Training in Advanced Life Support (NSCORT-ALS) at Purdue University, a complementary disinfection process, which uses ultra-violet (UV) radiation as the primary disinfectant and iodine as the residual disinfectant, is being developed. UV radiation was selected as the primary disinfectant because it is effective at inactivating a broad spectrum of microorganisms and has minimal potential to form disinfection byproducts. Iodine, which is effective at inactivating many microorganisms was selected as the residual disinfectant because it has the potential for dual use as an on-line UV monitor and a disinfectant. The dual use of iodine will be achieved using different iodine species. I2 will be used for secondary disinfection. Iodide (I-) and iodate (IO3-) will be used in the chemical actinometer to monitor the efficacy of the UV system. The actinometer system will consist of a small capillary tube installed within the UV reactor through which an I-/IO3- solution is pumped. When the actinometer solution is exposed to UV radiation, triiodide (I3-) is produced. The quantum yield for I3- formation will be used to evaluate the performance of the UV system. The iodine species present in the photo-reacted solution must be converted to I2 for use as a secondary disinfectant. Because of toxicological issues related to iodine exposure, residual iodine will be removed from the potable water at the point-of-use. The removed iodine will be transformed back to I- and reused in the actinometer system. The iodine recycle process will be continued throughout the mission duration, thereby limiting the need for 1 slide Related Documents:WM1, WM2, WM3, WM

Parameter Form for Subsystem: Liquid Phase/UV/Iodine (Water Disinfection)

3 pages Provider Notes:Subsystem parameters and graphs gathered from meeting with Kelly Pennel