Water Purification after Terrorist Acts and Accidents
Development of Combined Physical-Chemical Method of Purification of Drinking Water of High Toxic Compounds and Pathogenic Microflora, Contaminated in Terrorist Acts or Man-Caused Accidents
Tech Area / Field
- ENV-WPC/Water Pollution and Control/Environment
- CHE-IND/Industrial Chemistry and Chemical Process Engineering/Chemistry
3 Approved without Funding
Georgian Technical University, Georgia, Tbilisi
- A.N.Frumkin Institute of Physical Chemistry and Electrochemistry, Russia, Moscow
- Genentech, Inc., USA, CA, South San Francisco
Project summaryThe purpose of this work is to develop a new effective combined method of oxidation decomposition of high toxic compounds and water decontamination from pathogenic microorganisms, based on use of high intensity pulse ultraviolet continuous spectrum radiation and ozonators allowing to achieve gas ozone concentration of up to 200 mg/l.
The increasing major man-caused accidents accompanied by salvo-like pollution of water sources, as well as the possibility of terrorist acts with contamination of drinking water sources with high toxic compounds and pathogenic microorganisms make the development of new highly effective methods and technological means of water purification and decontamination extremely relevant.
The accumulated research experience in processes of water purification from complex organic contaminants in different countries evidences that the most promising method is their photo-oxidative decomposition, This method is based on use of ozone as oxidant and super-power xenon lamps with continuous spectrum of radiation, covering continuously the entire ultraviolet range up to the water passing bound, as ultraviolet radiation sources. Using ultraviolet radiation together with ozone treatment allows not only significantly reduce the ozone concentration required for decomposition of organic substance but also to considerably increase the depth of its decomposition.
This development is also characterized by use of the new generation of ozonators generating ozone with a concentration of up to 200 mg/l in ozone-oxygen mixture (in the existing analogues – 50-60 mg/l) and having small dimensions (10 times smaller than the correctly used analogs). Use of concentrated ozone allows to achieve in reactor a virtually non-convective opposing flow of water to be treated and ozone-oxygen mixtures, which, in its turn, ensures a significantly acceleration of the oxidation process.
The advantages of use of pulse xenon UV lamps of continuous radiation spectrum, as compared to the traditional mercury lamps, are as follows:
- Continuous spectrum of UV radiation of xenon lamps allows to cover the absorption bands of all species of microorganisms and contaminants, which makes this technology potentially universal, allowing, along with deep reliable disinfections of water, to neutralize organic high toxic compounds;
- Intensity of such sources of radiation is tens of thousands times higher than the intensity of the most powerful modern mercury lamps. High radiating power drastically changes the chemistry of reactions exposed to UV radiation and ensures decomposition of bacteria and toxins with a minimal power consumption and maximal efficiency;
- Process remains effective even with very high levels of initial bacterial contamination.
Competence of the Project participants. The participants of the Project have many years’ work experience in the area of photochemical destruction and photo-oxidative degradation of organic substances in water solutions.
The sphere of interest of the Project participants in the recent years includes the following:
- To study photochemical destruction and photo-oxidative degradation of organic substances in waste water of radiochemical production for their subsequent purification.
- To develop water and air cleaning and disinfection from high toxic chemical and poisonous substances and pathogenic microflora.
Expected results and their application. Methods of combined chemical and UV pulse water treatment with continuous spectrum radiation for destruction of microquantities of high-toxic organic substances will be developed
- Use of photo-oxidative methods for higher effectiveness and deeper purification of water from organic substances will be studied.
- Analysis of effectiveness of use of pulse high-intensity UV radiation of continuous spectrum for deep disinfection of drinking water from various types of pathogenic microorganisms (vegetative and cryptogamic forms of bacteria, viruses) will be made.
- Scientific-technical basis for the process will be developed and a pilot unit for purification of drinking water from high-toxic substances and pathogenic microflora will be made
The results of the work may be used in housing and communal services to supply water to civil population, including water supply in case of terrorist acts and man-caused accidents involving contamination of sources of drinking water with high toxic compounds and pathogenic microorganisms.
Use of the installations for drinking water supply developed as a result of the research conducted will almost completely eliminate the risk of epidemic outbreaks and mass poisoning of people both as a result of terrorist acts and in regions of unfavorable environmental and epidemiological situations, as well as in areas of emergencies.
Meeting ISTC Goals and Objectives.
Project implementation will
- Make it possible to engage weapon specialists in peaceful activity.
- Contribute to integration of the authors of the Project in the international scientific community.
- Support fundamental and applied research and development of technologies in the sphere of environmental protection.
Scope of work under the Project is designed for 2 years, including implementation of four interconnected tasks/objectives for development of scientific and technical basis of the process of application of combined physical and chemical methods of purification of drinking water polluted as a result of man-caused disasters or terrorist acts from high-toxic compounds and pathogenic micoflora, and creation of a pilot water treatment unit/plant based thereon.
Role of foreign collaborators. Information sharing and joint research work with the collaborators are expected to take place in the course of implementation of the Project. Direct meetings are planned to be held with the collaborators to discuss results and conduct workshops
Technological approach and methodology. To develop the process of application of combined physical and chemical methods of purification of drinking water, theoretical and experimental research methods and results earlier obtained by the project participants will be used. The authors’ previous works showed the possibility of use of this process for water purification from high-toxic compounds and pathogenic microflora. The new generation of ozonizers generating ozone with the concentration of up to 200 mg/L of ozone-oxygen mixture (the existing analogues generate ozone concentrations of 50-60 mg/L) will be used. Additionally, xenon continuous spectrum flashlamps with high spectral intensity within the range of 190 – 300 nm will be used as UV sources. The radiation spectrum of such lamps is continuous and its nature is similar to that of solar radiation spectrum. At the same time, in the range of 190 – 300 nm they have maximum photochemical and biocidal activity.
To implement the first task, the method of continuous spectrum UV radiation generated by xenon lamp will be applied. Imitators of poisonous substances and pesticide atrazin will be used as model substances
To implement the second task, new processes of oxidative degradation of organic substances, ADVANCED OXIDATION PROCESSES (AOP), based on the principle of combination of chemical and physical methods of influence, significantly accelerating the oxidation process will be used. The process scheme will represent a combination of ozonolysis with photochemical activation of the process by pulse UV radiation of continuous spectrum.
To implement the third task, analysis of application of pulse high-intensity UV radiation of continuous spectrum for deep disinfection of drinking water from various types of pathogenic microorganisms (vegetative and cryptogamic form of bacteria. Viruses) will be conducted, performance specification for making a pilot unit/plant has been developed.
To implement the fourth task, field tests of the pilot unit will be conducted.
Reliability of work results is ensured by experimental and theoretical tests of methods applied in implementation of various project objectives, by use of modern scientific methods and equipment, certified and tested devices and instruments, and by high-skilled personnel.