3rd International Symposium in O3 Ozone Applications
Ozone Chemistry, Ozone Generation & Ozone Water Treatment
Ozone in Medicine - June 27th 24th to 30th, 2000
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OZ-L-001: DEVELOPMENT OF OZONE APPLICATIONS IN CUBA.
Ozone Research Center.
Although ozone in the atmosphere since the formation of this, and was not detected until 1785 by Van Marum, baptized by Schönbein in 1840 and used in France in the disinfection of water from the Seine, followed by Nice in 1906, it was not until the 1950's that appeared in Cuba its first application, with the acquisition of a team, the firm Westinghouse, for the treatment of drinking water in the office building of the Cuban company of electricity.
Ozone in the Class of CNIC then Ozone Research Center, began the first studies in the early 1970's, using a laboratory equipment firm Gallenkamp, very low efficiency. From the seventies to date, has dabbled in various applications of ozone, which highlights first of all, basic research that gives scientific support to the applications of this gas.
The technologies developed in the Ozone Research Center with the use of ozone are: disinfection of clean water, to obtain veterinary medicines, bleaching sugar solutions, obtaining catalysts for the destruction of residual ozone disinfection of water for swimming pools, residual disinfection, bleaching cotton fabrics, desulfurization of petroleum, food preservation, discoloration of sugar cane wax and disinfection of rooms of plantings.
It also works in the ozone, which is widespread in Cuba and the development of ozone-generating equipment, used to generate the mid and high frequency line.
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OZ-PO-002: NEW APPROACHES TO DESIGN AND PRODUCTION OF LABORATORY AND THERAPEUTIC GRADE OZONE GENERATORS.
Den Rasplicka.
Ozone Services. Division of Yanco Industries Ltd., Canada
Therapeutic and laboratory grade ozonation systems utilizing the low frequency (50/60Hz) corona discharge ozone production process have dominated the field of Ultra Pure Ozone Applications for the last 20 - 30 years, coexisting with cold plasma based ozone generators originally fathered and developed by N. Tesla.
With swift progress in development of semiconductor components suitable for design and production of solid state high frequency and high voltage pulse power supplies we are witnessing the rise of a new generation of high frequency corona discharge ozonation systems.
Direct practical results of embracing this new trend is improved efficiency of ozone production (lower power consumption), significant reduction of size of ozonation systems, equipment production cost reduction and improved equipment reliability.
Strong growth of interest in ozone therapies mainly in veterinary field brought additional challenges in the form of urgent need for light, durable and reliable ozonation systems witch meet requirements for unrestricted mobility.
There is also strong evidence that mobility of ozonation systems will become one of main dominant factors in the process of bringing benefits of ozone therapies to people living in remote areas around the world. Consequently, new low power consumption 12 VDC ozonation systems are being developed and brought to a production.
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OZ-PO-003: OPTIMIZATION OF OZONE GENERATION USING GAS MIXTURES.
Thomas J. Manning.
Department of Chemistry, Valdosta State University, Valdosta, USA.
Ozone production from oxygen in the gas phase is often limited by the ability of the specific generation system to efficiently break the oxygen double bond to produce oxygen atoms. Systems such as corona discharge units, lasers, and UV light sources have been used to produce the enthalpy necessary to convert oxygen in ozone.
In most systems, at least 90% of the energy is wasted not only driving up energy consumption but also introducing the need for additional equipment to draw heat away from the ozone production area.
In building an ideal ozone generation system, we identify three basic parameters that have to be meet for commercial viability to increase: low capital cost and low maintenance cost; high conversion efficiency of oxygen to ozone to minimize gas waste; and a low power consumption or a very efficient coupling of the energy into the dissociation of the oxygen double bond.
In this paper we will talk about the design, construction and results of building a low cost system that uses the inert gases as catalysts in the production of ozone from a corona discharge. Specifically will talk about the economical use of argon to dramatically increase the electron density (e-/cm3) in the discharge, accelerating the conversion of oxygen in oxygen atoms.
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OZ-PO-004: EVALUATION OF THE EFFICIENCY OF CONTACT USING THE bubble column hydrodynamic modeling.
Ozone Research Center.
In the past 15 years tracer studies specialists have enabled a better understanding of the hydraulic behavior of a reactor for water ozonation. These studies have resulted in new designs and improve reactor operation, searching the pattern of flux as possible to store plug flow behavior, known as the best for the application of ozone oxidation and disinfection. Moreover, the hydrodynamic study to determine the effective time of contact, to evaluate CT criteria developed by EPA in 1989.
The aim of this study was to evaluate the hydrodynamics of bubble column type reactor by testing different streams of tracer gas and liquid, to evaluate the efficiency of contact and propose appropriate operating conditions. The intervals of the experimental conditions for the flows of both phases (gas flow 0.18 to 0.54 m 3 / h for the flow of fluid from 1 to 3 m 3 / h) correspond to the intervals of operation of the systems installed ozone treatment.
From the hydrodynamic modeling assessed the fit of different models reported in the literature and proposes a combined model that adequately responds to the pattern of flow of the liquid phase. We also analyzed the impact of the hydrodynamics in the contact efficiency in mass transfer and hence in disinfection. Furthermore hydrodynamic parameters are determined as the average diameter of bubble and retention of gas in the liquid models are proposed for estimation.
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OZ-PO-005: HYDRODYNAMICS AND MASS TRANSFER IN CONVENTIONAL OZONATION REACTORS FOR DRINKING WATER TREATMENT: FULL SCALE OPERATION DATA AND MODELLING.
Z. Do-Quang (a) and M. Roustan (b).
(a) CIRSEE, Lyonnaise des Eaux, Le Pecq, (b) Département de Génie des Procédés Industriels-INSA, Toulouse, France.
In the actual context of drinking water quality standards growing stringency and water treatment reliability improvement, the impact of reactor design becomes of primary importance for the process efficiency and cost.
In water ozonation several parameters influence the effectiveness of ozone mass gas-liquid transfer and the oxidation reaction performance. These include the contactor geometry, the gas and water flow rates, the gas and water flow ratio and, finally, the diffuser position.
For water treatment engineers the understanding of the impact of each of these parameters on the entire process in full-scale systems is an important issue for the on-line control of the entire Water Treatment Works.
Operation data on full scale ozonation reactors is reported and discussed in terms of hydrodynamic performance of the system (expressed as T10/t) and mass transfer efficiency. Several full scale reactors having volumes of 200 to 400 m3 and hydraulic residence times between 8 and 20 minutes have been studied.
Tracer studies with lithium chloride have been performed and ozone residual concentrations (in the gas and water) have been measured in order to propose a mathematical model of these reactors.
Then their performance is evaluated for different water quality objectives (such as disinfection and micro-pollutant oxidation). Specific problems relative to the full scale operation of the plants (process regulation and optimization in case of raw water quality variation and treatment goal changes) are addressed as well.
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OZ-PO-006: HYDRODYNAMICS AND OZONE MASS TRANSFER IN A LABORATORY PILOT REACTOR EQUIPPED WITH STATIC MIXERS: EXPERIMENTAL STUDY AND MATHEMATICAL MODELLING.
M. Roustan (a) and Z. Do-Quang (b).
(a) Département de Génie des Procédés Industriels-INSA, Toulouse, (b ) CIRSEE, Lyonnaise des Eaux, Le Pecq, France.
Ozonation in water treatment is usually performed in conventional bubble column reactors. However alternative contacting systems are used nowadays to achieve high mass transfer performances. The interest of using static mixers in the ozonation reactors has already been shown when high amounts of ozone are required by the process and when mass transfer phenomena are the limiting step.
Static mixers are commonly used for gas-liquid mixing in different fields of industry, but are not widely used in water treatment. They are composed of mixing elements maintained motionless in the pipe and produce mixing and turbulence by dividing the main flow in a multitude of partial flows which are again combined and again divided.
When the gas is mixed in the static mixer with pressurized water it is possible to obtain micro-bubbles and this increase 10 to 100 time the interfacial area of transfer between the gas and the liquid and thus increase by the same factor the velocity of ozone mass transfer.
The main advantage of static mixers is to create high interfacial area of exchange in comparison to the conventional bubble column reactors. However to be able to control this parameter it is necessary to understand the influence of the design and operating conditions on the bubble size, gas hold up, head loss.
Empirical relationships are available to estimate the mass transfer in static mixer reactors as a function of the gas-to-liquid flow ratio and the head loss. However, they account for the specific geometry of the static mixer and the reactor and are difficult to extrapolate. Therefore accurate experimental data has to be generated in order to be able to develop a general deterministic model for this kind of systems.
In this paper some experimental data is presented and a modelling approach is proposed to describe the hydrodynamics and the mass transfer in a pilot ozonation reactor equipped with static mixers.
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OZ-PO-007: POTENTIAL FORMATION OF BY-PRODUCTS DURING ADVANCED DISINFECTION OF MUNICIPAL WASTEWATER WITH UV, OZONE OR PERACETIC ACID.
L. Liberti (a), A. Lopez (b) and M. Notarnicola (a).
(a) Institute of Environment and Land Engineering, 2nd Faculty of Engineering, Polytechnic University of Bari, Taranto, (b) National Research Council, Bari, Italy.
Formation and hazardous effects of DBPs by alternative disinfectants are still a matter of further research before alternative disinfection methods to chlorination can be safely applied. A multinational project on agriculture reuse of treated wastewater was carried out. The Italian role in the project was aimed at comparing pathogens removal, DBP formation and cost effectiveness of alternative methods to chlorination based on UV, PAA and O3.
This paper reports the 100 m3/h pilot plant investigation concerning the search for potential DBPs (nitro-phenols and N-nitroso-amines, total epoxides and 2/4/2,4 chloro-phenols, total aldehydes, bromates and bromoform) following UV, PAA and O3 respectively during the advanced disinfection of clarified and clarified-filtered feeds.
The disinfecting doses (100 and 160 mWs/cm2for UV, 10 ppm and 30 min for PAA and 15 ppm and 10 min for O3) were those necessary for achieving either the Californian standard or the WHO guideline for unrestricted agriculture reuse of wastewater. None of the N-derivatives searched for after UV disinfection was ever detected by GC-MS analytical technique whilst LC-MS analysis excluded also the formation of non-volatile DBP, suggesting the absence of detectable photochemical reactions at UV doses usually used in wastewater disinfection.
Epoxides and chlorinated phenols did not follow PAA disinfection within instrumental detection limits. The only DBPs were acetic acid (17 %) and hydrogen peroxide (23 %), both occurring initially in the used mixture.
Approx. 350 ppb of aldehydes formed during O3 disinfection, while the expected formation of bromoform and bromates from bromide-containing wastewater did not occur, probably due to relatively high NH4+ content and basic pH of the feeds.
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OZ-PO-008: IMPROVEMENT OF PROCESS WATER QUALITY OF A BREWERY USING OZONE.
Philippe Charlet and Filipe Montalvão.
Rio Technology Center, White Martins Gases Industriais S.A., Brazil.
An industrial ozonation system has been set up at a brewery mill in the south of Brazil to treat process water, replacing chlorine. The objective of the mill was to abandon chlorine for pretreatment and switch to ozonation in order to reduce the creation of regulated disinfection by-products Trihalomethanes (THM’s) below. The current Brazilian regulations.
The quality of the water used in that mill, coming from a river, has always been considered as a critical issue. A primary treatment is realized through addition of aluminum sulfate, lime and decantation of organic matter and metals, followed by a double filtration.
Ozone was applied in two stages using classic contact columns: first in a pre-ozonation before flocculation of organic matter and then after filtration. A final addition of a low quantity of chlorine was still considered since it is necessary to maintain a disinfectant residual in water during the time of storage in reservatories. Before using water in the process, a last filtration with active charcoal is realized.
Ozonation was applied in the first stage to enhance the removal of organic matter through coagulating effects. Pre-ozonation conditions were optimized to improve the subsequent flocculation settling with aluminum sulfate. Regarding the formation of chlorination by-products, the four THM’s were analyzed at six points of the water pretreatment process during several months.
Results have clearly shown that after post-ozonation the level of total THM’s was very low, and mainly composed of chloroform. With ozonation, a reduction of 80 % in the formation of THMs was achieved in the industrial water, when compared to chlorination. The final levels of THMs are now well below the current legislation limits.
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OZ-PO-009: OPTIMIZATION OF AN INTEGRATED WASTEWATER TREATMENT SYSTEM WITH OZONE TO REMOVE COLOR IN A BRAZILIAN TEXTILE MILL.
Filipe Montalvão and Philippe Charlet.
Rio Technology Center, White Martins Gases Industriais S.A., Brazil.
The final color of the treated effluent is the most critical issue in textile industry regarding compliance to environmental regulations. For that purpose an integrated system for wastewater treatment has been set up at a textile mill in the south of Brazil; it consists of a sequence of a biological treatment, a polymers addition and an ozone treatment.
This paper presents the performance of this system on color removal obtained on the final effluent. This mill is representative of the Brazilian textile industry: it produces an average of 600 ton/month of mesh coming from thread. 90 % of the production is cotton mesh and the remaining from synthetic threads of polyester and others. Most of the dyes are reactive.
The water treatment plant consists of primary system with pH neutralization using CO2, a secondary system with an activated sludge reactor, a settling tank where the addition of polymers is realized and finally an ozonation system (generator and contact columns). Results have shown that polymers alone are unable to remove the final color below the limit of current legislation. This could be achieved by the final ozonation.
This study has clearly demonstrated that the major problem associated with the application of ozone after biological treatment is the variation of quality of this treated effluent. A low quality can considerably decrease the efficiency of ozone oxidation and particularly it was shown that the level of suspended solids is one of the major parameter on ozone consumption.
Full scale tests are currently performed to optimize the consumption of flocculating agents and ozone dose to save costs maintaining a high quality of the treated effluent.
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OZ-PO-010: GENERAL AGRICULTURAL AND SOME OTHER APPLICATIONS OF OZONE, 10 YEARS EXPERIENCE.
Ariel Villarreal (a) and Arnulfo Perez (b).
(a) Realtec, S.A. de C.V., Ozone Consultant. Air, Water and Soil Treatment, (b) Realtec, S.A. de C.V., Mexico.
The applications of ozone technology in food and different water treatments around the world it is not a new matter in some European countries, beginning at the new era of the XXth century, but even today still "new" and unknown in most of the American continent.
In Mexico, the knowledge of ozone science and technology, is a little older than 10 years. Few years before water treatment applications was applied by some advanced pioneers. Ozone was used to eliminate odors from rest rooms, offices, disinfection for hospital rooms and small places.
This new controversial substance, Ozone, was described as main pollutant component of smog gases on Mexico City’s atmosphere, and start been used on food and related products as "good ozone", by Mexican agricultural and food technologists with good results. Small ozone generators from Spain, open the gate to some curious "Mexican ozone pioneers", to hi technology ozone applications to many common agricultural, food storage, greenhouses, fruit and vegetables disinfection problems.
Water treatment as effective, low price and operational systems were used to clean dirt and dangerous E. coli, contaminated water to feed drinking troughs for poultry, hogs and dairy cows and to clean their by-products as food.
Today dairy cattle farms with more than 3600 heads and industrial waste water treatment are benefited with ozone technology and applications developed in Mexico.
This paper shows pictures on this applications and synergetic technologies and it benefits for food and health with a not expensive and good quality technology. The idea of an optimistic usage of ozone in food industry and agricultural applications is now a real, effective, present and commercial practice in the first world countries, for example on cold storage and irrigation water for horticultural greenhouses, and is introduced by Realtec since a decade in Mexico.
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OZ-PO-011: PLANT SEWAGE TREATMENT. REUSE FOR IRRIGATION GOLF BY OZONE.
Oswaldo Corsino.
Trailigaz Compagnie Générale de l'Ozone, France.
Ozone facilities Almeria Spain Estepona are made for wastewater treatment and reuse for irrigation, with an ozone production of 20 kg / h with two generators of 10 kg / h each, but with the difference of Almeria produce ozone from air and Estepona from liquid oxygen. As to the chemical parameters of the treatment can be considered similar, given the characteristics of a standard residual water.
The treatment plant wastewater for reuse Estepona for irrigation of golf courses is an example to the world as it is the largest ozone plant that will exist after. Trailigaz Acosol and came together to meet this challenge to build wastewater performing a post-treatment by ozone.
The use of ozone as an oxidant has proven effective both in treating drinking water, industrial waste or other domains as well as special treatment. New technology and advances in the field of ozone generation and dissemination, have allowed a significant reduction in the exploitation of plants and better use of the treatment phases.
Trailigaz with over 2500 installations worldwide ozone is continuously researching their laboratories the generation and diffusion of ozone. The result is a new set of medium frequency generators with low power consumption, working at concentrations of 35 gO 3 / m 3 from air and 200 gO 3 / m3 from oxygen.
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OZ-PO-012: OZONE AS AN ANTIMICROBIAL AGENT IN FOOD PROCESSING.
Dee M. Graham.
R and D Enterprises, California, USA.
The discovery during the past three years of more virulent microbes, e.g., E. coli 0157:H7, Listeria, Chryptosporidiumand Salmonella has refocused the need for more effective antimicrobial agents. Ozone emerges as a valuable new tool for food processing applications. An overview of the history of ozone will be presented, including the leadership of the Electric Power Research Institute in preparing an Expert Panel Report related to the use of ozone in food processing. This dates back to applications in France as early as 1902.
Some of the regulatory constraints in the USA will be discussed. Some Technical Hurdles and Applications for Ozone in food processing will be identified. Critical factors observed in a variety of new ozone food installations over the past three years will be reviewed. This information will help in the evaluation, selection and design of ozone systems for use in food processing. Applications to be discussed will include fresh apples, sausage processing equipment, poultry carcass sanitation, storage warehouses, and fresh produce.
The need for definitive data on CT values for a variety of microorganisms of public health interest on many different food product systems will be emphasized. Critical factors influencing ozone effectiveness and safety include temperature of application, dissolved solids such as organic load, iron magnesium, and bromine in process water.
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OZ-PO-013: STUDY OF BLEACHING KINETICS OF OZONE WITH SPIRITS clarified.
Ozone Research Center,
Higher Polytechnic Institute.
The use of ozone as a bleaching agent clarified liquor Cuban is a technology that has proven highly effective at different scales. This paper develops a methodology for calculating the effective kinetic constants characterizing the reaction system obtaining values of order 10 5 L / mol · s, from the application of the theory of Danckwerts, for that there were some considerations possible to estimate the dye concentration in mol / L.
In parallel, a comparison with results obtained in the study of model olefins which formed the basis for the development of the methodology of calculation of kinetic constants. Also presented are models that characterize the relationship between the main process variables, including highlights the ozone dose applied, the ozone consumption rate and the initial color of the liquor.
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OZ-PO-014: INACTIVATION OF OZONE dacarbazine. STUDY OF THE REACTION.
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Research and Drug Development,
Ozone Research Center,
School of Chemistry,
Center of Pharmaceutical Chemistry.
Dacarbazine if chemically named as acid, 5 - (3,3-dimethyl-1-trazenil) -1H-imidazole-4-carboxamide, this drug as the majority of antineoplastic alkylatingagents in common Takes ownership of the reactions involved in stronglyelectrophilic lead to the formation of covalent bonds with various nucleophilicsubstances in biological average, so that at different stages involved dividing thecell death of these provoking. Both their carcinogenic and mutagenic properties,and their effects short off time, as by between selectivity CELL short of healthy and diseased agent is undesirable residues in the medical practice and the pharmaceutical industry, THOUGH classified as highly dangerous and treated ifrecommended to be disposed of.
This work had as the study of the dacarbazinereaction with ozone target as possible method of sample inactivación.Para this objective if performed Experiences with aqueous solutions (1 mmol / L) of thedrug different pH (3.0 to 7.0) in a reactor (100 mL) with bubbling (3.3 to 3.6 L / h)ozone in oxygen (16.0 to 18.0 mg / L) produced in a laboratory generator.
Development work if the ISC analytical TLC and used for HPLC monitoring of thereaction and to isolate the reaction products . if isolated reaction product if spectroscopic and characterized ISC, UV, IR, NMR spectroscopy and massProposes When the mechanism of the reaction if the stoichiometry of the reactionif the study and performed quantum mechanical calculations by semi-empiricalMethods first reaction step.
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OZ-PO-015: CHLORINATED UNSATURATED HYDROCARBONS ELIMINATION BY OZONE.
T. Poznyak (a) and A. Manzo (b).
(a) Superior School of Chemical Engineering,
(b) National Polytechnic Institute of Mexico (ESIQIE-IPN), Mexico.
More common water pollutants are trichloroethylene (TCE), tetrachloroethylene (PCE), carbon tetrachloride (CTC) and vinyl chloride (VC) among others, which are the chlorinated unsaturated hydrocarbons (CUH). They with greater frequency can be found in underground water.
Furthermore, composed TCE and PCE exist in residual water of different industries such as oil refineries, vulcanization, production of pesticides, agriculture, etc. Ozonation is shown to be an effective method for removing CUH from water.
The reaction rate constant for unsaturated hydrocarbons is high (about 105 L/ mol s), but ozone is selective and in the direct pathway reacts slowly with CUH. Its reaction rate constant turns out to be about 10000 times less. The rate constant turns out to be a lumped parameter, incorporating both reaction kinetics and mass transfer characteristics of the system.
Several system parameters which have a great influence to mass transfer, such as gas flow rate, partial pressure of applied ozone, degree of mixing, bubble size and reactor geometry, are inherently combined within the rate constant and the ozone dose. In the present work we propose the mathematical model of ozonation process in water for a semi-batch reactor (250 mL) at constant pressure and temperature.
Based on the computer simulation, we obtain the optimal conditions to perform the maximal elimination of TCE and PCE from water. The elimination conditions were as follows: initial ozone concentration: 1.0 x 10-3 mol/L, ozone-oxygen mixture flow rate: 5 L/ min and the reaction temperature: 18 ºC. The experimental and simulation dates show very well coincidence.
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OZ-PO-016: SOME USES OF OZONE IN THE PRECIOUS MINING.
Francisco Raul Carrillo, Antonio Gonzalez, Fabiola Nava and Alejandro Uribe.
Center for Research and Advanced Studies of IPN, Mexico.
The cyanide, the main process used to remove over 70% of the gold and silver in the world, has certain limitations such as its low efficiency for the treatment of so-called refractory ores with gold and silver (precisely refractory to cyanidation) , the high consumption of cyanide because minerals with high sulfur content and toxicity of the effluent end of the process.
This paper presents some preliminary tests, both synthetic and industrial samples to the laboratory on the use of ozone for the treatment of the three problems mentioned.
The results show that ozone can offer an attractive option for improving the cyanide process in the treatment of refractory ores and for recovering and recycling the cyanide consumed by the sulfur contained in the minerals and also to decrease the toxicity of effluent end of the cyanidation.
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OZ-PO-017: influence of pH on the oxidation of thiocyanate with ozone.
Francisco Raul Carrillo, Fabiola Nava and Alejandro Uribe.
Center for Research and Advanced Studies of IPN, Mexico.
The thiocyanate (SCN-), is a compound produced during the coking of coal operations and in the cyanidation metallurgical ore containing precious sulfur. Thiocyanate is generally produced by reactions between cyanide ion and sulfur, present in variable amounts (20 to 2000 mg / L) in effluent from these processes.
Although thiocyanate is not a highly toxic compound (not shown in the environmental standards on water), may biodegrade to more toxic species such as cyanide.This paper presents the thiocyanate oxidation using ozone, the thermodynamics and kinetics in acidic and alkaline solutions.
The results show that oxidation of thiocyanate occurs by direct oxidation of this species with ozone generating different reaction products, depending on the pH, which also alters the kinetics of the reaction. The results suggest that the oxidation of thiocyanate can be controlled to obtain a compound, cyanide, which can be recovered, or effluent with less potential contaminants.
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OZ-P-018: KINETIC STUDY OF THE PHENOL AND CHLOROPHENOLS OZONATION: THE PHENOLS ELIMINATION OPTIMIZATION.
T. Poznyak (a) and J. L. Vivero Escoto (b).
(a) Superior School of Chemical Engineering,
(b) National Polytechnic Institute of Mexico (ESIQIE - IPN), Mexico.
Chlorophenols (CPHs) are used widely in the manufacture of pesticides, fungicides, and other industrial chemicals. Chlorination of phenols during the desinfection of wastewater also produces chlorophenols. That is why the effective methods to remove phenols and chlorophenols (PHs and CPHs) are needed.
Biological oxidation and adsorption on activated carbon can be considered as one of them, but uneconomically long residence times are required to reduce the PHs and CPHs concentrations to the discharge level allowed by emission regulation, especially for wastes with high phenol content.
Ozone is effective for degradation of many pollutants including PHs and CPHs. Also it does not form more toxic compounds during oxidation. Thus, ozonation appears to be an attractive method for treatment of industrial effluents.
Numerous studies have been conducted addressing the kinetics and the dynamics of PHs and CPHs oxidation by ozone. In this work we modify the mathematical model of the PHs and CPHs ozonation in aqueous media. This model includes the ozone mass balance, the equations concerning the ozone dissolution in water and the differential equations of chemical reactions.
This mathematical model permits to realize the simulation and optimization of the oxidation process based on its kinetic parameters. This model helps to find the optimal conditions to perform the best elimination of the PH and CPHs mixture.
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OZ-P-019: WASTEWATER TREATMENT BY cyanide oxidation with ozone.
F. Nava, FR Carrillo, A. Uribe and R. Perez.
Center for Research and Advanced Studies of IPN-Unidad Saltillo, Mexico.
The most used method for extracting gold and silver is cyanide (recovery of up to 99%). This process is efficient and economical, but presents the problem of generating a toxic effluent which is necessary to treat due to its content of heavy metals and cyanide.
Different methods of treatment (SO 2 / air, H 2 O 2 , chlorine) to oxidize the cyanide to nontoxic species, but often there are some problems such as difficulty in removing heavy metals, the toxicity of the products formed or high cost required to achieve acceptable limits of contaminants.
Ozone has been used efficiently in the destruction of cyanide in effluents simple, however, the effluent cyanide are particularly complicated by the presence of different species (metals, thiocyanate, etc.).
In significant concentrations. The lack of information on the effect exerted these species in the efficiency and economy of the process has limited its industrial application. In this paper we present results from the oxidation of cyanide effluent with ozone in cyanidation process.
Tests were performed with synthetic and industrial solutions in a conventional bubbling column and studied the effect of various parameters (pH, addition rate and presence of ozone and copper thiocyanate) in the consumption of ozone and the reaction rate.
The results show that the ozonation can be considered as an attractive alternative from the standpoint of efficiency and reaction time, for the treatment of effluents cyanidation. The economy of the process will depend upon the original composition of the effluent.
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OZ-P-020: A STUDY OF THE REACTION OF OZONE WITH flucytosine.
Research and Drug Development,
Ozone Research Center,
Faculty of Chemistry,,
Center of Pharmaceutical Chemistry.
Flucytosine is chemically known as 5-fluorocytosine. This drug is an antiviral agent, which by its chemical structure is very similar to the antineoplastic agent fluorouracil pyrimidine analog. This work aims to study the reaction of flucytosine with ozone.
For this purpose experiments were conducted with aqueous solutions (1 mmol / L) of the drug at different pH (3.0 to 7.0) in a reactor (100 mL) with bubbling (3.3 to 3.6 L / h ) of ozone in oxygen (16.0 to 18.0 mg / L) produced in a laboratory generator. Work in the development of analytical techniques were used for TLC and HPLC control the reaction and isolating the reaction products.
The product was isolated from the reaction and was characterized by spectroscopic techniques, UV, IR, NMR ( 1 H, 13 C) and mass spectroscopy, it is proposed reaction mechanism, we studied the reaction stoichiometry and calculations were made by quantum-mechanical semi empirical methods (PM3) of the reaction.
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OZ-PO-021: A STUDY OF THE REACTION OF OZONE WITH INACTIVATION cyclophosphamide.
Research and Drug Development,
Ozone Research Center,
Center of Pharmaceutical Chemistry.
Cyclophosphamide is an antineoplastic agent classified according to their structure, such as nitrogen mustard. These compounds react by an alkylation mechanism forming covalent bonds with various nucleophilic substances, such as sulfhydryl groups, hydroxyl, phosphate and carboxyl, which form an important part in the composition of the DNA, causing irreversible cell damage.
For this reason is considered high risk handling of waste are generated both in medical practice and in the manufacture of the finished product. In this paper we propose to work with artificial waste of cyclophosphamide 1 mmol / L with a mixture ozone / oxygen using a 100 mL reactor with bubbling from 3.3 to 3.6 L / h.
This oxidative system we reported satisfactory results providing inactive degradation products that we intend to characterize. Therefore the analytical determination of cyclophosphamide and their degradation products was analyzed by reverse phase HPLC.
A method was developed by reverse phase preparative HPLC to isolate the major product of the reaction. The eluate was concentrated by lyophilization isolated and characterized by spectroscopic techniques such as IR, NMR ( 1 H, 13 C) and mass spectrometry. We propose probable chemical structure for this product and the possible reaction mechanism of ozone.
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OZ-P-022: THERAPEUTIC OZOMED OZONE GENERATOR 401.
Ozone Research Center.
For over 15 years have been developing and building ozone generators in Cuba using the line frequency and the average frequency for operation. With the development of technology has been applied high frequency for ozone generation in both the ozone generators for industrial use as a medicine.
The ozone generating equipment for therapeutic use presented in this paper has the following characteristics: regulation of working time, digital display of the percent of applied voltage, overcurrent protection electronics, ignition and continuous generation time to protect the circuit from generation increasing equipment reliability, less weight than his predecessor, lower power consumption when working on electrical resonance and greater compaction of the electronics.
Was obtained a great improvement in the efficiency of generation, a greater stability in the production of ozone and the concentration is independent of changes in frequency and voltage.
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OZ-P-023: INDUSTRIAL AQOZO ozonizer - MF.
Centro de Investigaciones del Ozone.
The Industrial ozonizer AQOZO-MF is a new line in the construction of ozone generating equipment Ozone Research Center for industrial use. Was designed with the aim of carrying out the treatment and purification of water for industrial use for the treatment of wastewater and for the treatment of water used in swimming pool.
Among the most important goals are pursued with the design of the ozonizer are: the increase in ozone production, better use of the metallized area of the generating tubes, decrease in high voltage applied to the generator tubes for a given output, reduction in power consumption relative to a traditional ozone generator of low frequency or line frequency (60 Hz) and including a control circuit of internal process within the equipment; also required the design and construction of a cabinet that provide: installation, maintenance, equipment repair, and reproduction.
Was achieved for the furniture industrial design that allows the reproduction of similar equipment, also allowing the modernization or development of it without the need to vary the design. This machine has an upper and modularity allows increasing the generation capacity of ozone according to the application required. We obtained a relationship man-object-environment, higher than the previous prototype.
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OZ-P-024: TEAM OZONE GENERATOR FOR HOME: OZONEY.
Ozone Research Center.
It belongs to a new production line of ozone generators for domestic use of the Ozone Research Center. It is used for treatment and water purification for drinking, washing of foods eaten raw, personal hygiene, washing the dishes (thanks to the bactericidal, germicidal and fungicidal ozone). Can be used in homes, cafes, offices, schools, etc.. eliminating the need to consume boiled or bottled water.
The most important assumptions are: a high level in the production and concentration of ozone dissolved in water, low power consumption, low cost, small size and weight, easy installation and operation. It consists of parts electronics, mechanics, hydraulics and pneumatics.
Comprises: generating low frequency pulse trains modulated by the signal from a high frequency generator. This signal is then applied to the amplifier that drives the lift system voltage. The high voltage is applied to the tube obtained generator, which efficiently uses energy applied to reduce the thickness of the dielectric, without affecting the flow of air passing between the two concentric tubes, achieving greater air exposure time to effect discharge Electric.
The solenoid valve allows water to pass only when the equipment is energized. The ejector establishing the airflow through the generator and performs efficiently mixing the water with ozone. The non-return valve ensures that the water is below the generator and the dispenser can collect the ozonated water leaving the team.
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OZ-P-025: OZONE APLICATION IN SWIMMING POOL WATER TREATMENT.
Centro de Investigaciones del Ozono.
This paper presents the results of the evaluation throughout one year of a technology of swimming pool water treatment with ozone under environmental conditions of Cuba, which is a novelty, verifying that under evaluated operating conditions it has been obtained water with the required physic-chemist and microbiological quality according to up-to-date standard, which one guaranteed a nice and safe water, without risks for the health bathers.
The study was divided in two periods well defined, with different characteristics, such as climatological and swimming pool water temperature and bather number.
To divide the work in two periods allows the definition of the operation’s parameters and reagent doses to apply in the treatment, on winter and summer. It have been recommended an ozone dose between 2 and 3 g/m3, a sodium bromide dose between 10 and 20 g/m3 and diary volume used of chlorhidric acid of 1 to 2 L, it have been used cupric sulfate as alguaecide in a dose of 0,5 and 3,0 g/m3, and aluminum sulfate as a clotling in a dose of 5 to 10 g/m3.
Annual operation cost for a swimming pool of 500 m3 of capacity would be $ 15 146 and the cost in order to treat one m3 of water will be $ 0,07 for 8 hours of recirculating time respectively. On the other hand, the treatment system with ozone presents economical advantages respect to cloration, allowing the water conservation this is very important due to the high prices and the relative scarcity of this important resource.
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OZ-P-026: MICROBIOLOGICAL EVALUATION PROCESS OF OZONE IN A bubble column pilot plant scale.
Ozone Research Center.
To evaluate the effectiveness of ozone in the disinfection process is performed experiments in a pilot plant operating under conditions similar to water treatment systems installed in different plants. We used a relatively low dose of 2.16 g / m 3 and a relatively high dose of 6.48 g / m 3 and was based on a high initial concentration of 10 2 CFU of Pseudomonas aeruginosa .
The results obtained in this study were very satisfactory, since in all experiences inactivation is achieved in the samples. In general under the conditions studied dissolved ozone concentrations obtained at the output of the column is above 0.4 g / m 3 , the recommended minimum value, which is taken as a fundamental design criterion in the facility.
The results corroborate the high ozone disinfection capability and effectiveness in the inactivation of this microorganism, which turns out to be very resistant to other disinfectants and is easily spread in pipes and water reservoirs in Cuba.Parallel to the experiments carried out at gas flows of 0.18 and 0.36 m 3 / h, are reported CT 10 obtained.
The T 10 are obtained from a tracer study conducted and the average concentration of dissolved ozone is the average of the concentrations measured in the three samples taken.
The CT obtained are higher than 0.47 g min / m 3 , a value recommended for disinfecting water with ozone for U.S. EPA 1989, with the aim of ensuring 2 log inactivation of Giardia cysts at 298 K and pH 6 - 9.
The CT obtained indicate that the design criteria traditionally used in systems with ozone water disinfection facilities, may involve overdesign in terms of operating conditions and column dimensions, exerts different actions
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OZ-P-027: THE EFFECT OF OZONATION IN SURFACE WATER PURIFICATION TREATMENT.
N.Kaiga; S.Nakano; K.Tsunoda and T.Ishii.
Toshiba Corporation, 1-1-1, Shibaura, Minato-ku, Tokyo, Science University of Tokyo, 1-3, Kagurazaka, Shinjuku-ku, Japan.
Fluorescence analysis has identified a trace of natural organic materials (NOM) contained in the surface water, raw water for drinking water, as fulvic acid of humic constituents.
For the fluorescence intensity of NOM, the following have been verified:
1) the fluorescence intensity is reduced by chlorination during the water purification process,
2) the intensity is proportional to THMFP, and
3) the intensity and THMFP are reduced by ozonation.
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OZ-P-028: COMPUTER SIMULATION OF PROCESSES IN A HIGH FREQUENCY OZONE PLANT.
Semion V. Shapiro.
Dept. of Physics, Ufa Technological Institute of Service, Russia.
The application of high frequency ozone plants allows us to increase ozone production. In the research laboratory of the Department of Physics of the Ufa Technology Institute of Service, the original high frequency ozone plants with running barrier discharge were designed. The design of these ozone plants allows effectivity to use air for obtaining ozone.
In order to obtain an optimum design data, in the ozone unit, a computer simulation by means of a Maple mathematical packet was carried out. The given method allows us to calculate the composite electrical fields with N electrodes (high-voltage welding electrodes).
The distribution of the isotentions curves (i. e. geometrical places of points, in which in one a module of field intensity |E| = const) for six and twelve electrode ozone plants are shown. Along these curves there is a border (limit) of ionized and not ionized area of a digit zone. In an ionized zone there are chemical processes of generation of ozone.
In this study, the predicted data describing productivity of a digit zone of an ozone plant is shown. The outcomes of simulation have allowed us to elaborate a technique of analytical design of the ozone plants. Trial samples of ozone plants with relative productivity 25 grams/hours on 1 kg of the consumption of fissile stuffs are made.
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Source: Ozone Research Center
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