Rip G. Rice

Applications of ozone for industrial wastewater treatment — A review

Abstract This paper presents a detailed review of published applications of ozone for treating many types of industrial wastewaters. Applications of ozone technologies to control pollution in full‐scale industrial wastewater treatment plants in the areas of recycling marine aquaria, electroplating wastes, electronic chip manufacture, textiles, and petroleum refineries, are discussed. The rising acceptance of ozone as a replacement bleaching agent for paper pulp to eliminate the discharge of halogenated effluents from pulp bleaching plants also is traced. Newer applications for ozone in treating rubber additive wastewaters, landfill leachates, and detergents in municipal wastewaters are summarized briefly. The combination of ozone oxidation followed by biological treatment has been installed full‐scale at a large German industrial chemical complex. Ozone coupled with ultraviolet radiation and/or hydrogen peroxide (advanced oxidation) is being utilized to destroy organic contaminants in groundwaters at muni...

Ozone in the United States of America -- State-Of-The-Art

Abstract Applications for ozone in the United States have evolved through a lengthy maturation process, which began with drinking water treatment (taste/odor/color removal) in the early 1900s, and grew slowly until acceleration began in the mid-1980s. Although deodorization became a stable market in the 1960s-1970s, these applications were small, for the most part. One of the largest uses for ozone is oxidation of process chemicals in the chemical industry, which began in the USA about the 1940s, and subsequently has spread worldwide. Today, thanks primarily to environmental regulatory pressures which began to impact ozone in the mid-1980s, ozone now is used increasingly in the USA for drinking water treatment and for some municipal and industrial wastewater applications. The U.S. Environmental Protection Agency (EPA) has recognized the growing importance of ozone (> 200 drinking water plants use ozone today), and has appointed IOA representatives to two of its regulatory development committees as stakeho...

The use of Ozone to Control trihalomethanes in Drinking water Treatment

Abstract Trihalomethanes (THMs) are produced when certain organic materials are treated with chlorine. The U.S. EPA recently has promulgated a Maximum Contaminant Level for THMs in finished drinking water of 0.10 mg/L. Although ozone will not oxidize THMs at any significant rate once they have been formed, its use has been studied at many North American water treatment plants for oxidation of THM precursors before chlorine is added. In most cases ozonation prior to chlorination lowers THM formation potential (THMFP), but there have been many reports of increased THM formation when ozonation is followed by chlorination. The known chemistry of THM formation and of ozone oxidation of organic materials to both destroy and to form THM precursors is discussed to explain these results. In addition, recommendations are made for the use of ozone at various points in the standard drinking water treatment process, by which THM levels in the finished water can be decreased. These methods include ozonation at any poin...

Ozone Disinfection of Municipal Wastewater -- Current State-of-the-art

Abstract The use of ozone for the disinfection of sewage has been escalating since the early 1970s, primarily in the United States. Today there are 32 operational wastewater treatment plants in the USA incorporating ozonation, although only 19 ozonation systems are actually operating as of late 1981. Another 11 plants are under construction and another 9 are in design. Host of these plants utilize ozone for disinfection. Available full-scale plant operational data, data from pilot plant testing, data on efficiencies of disinfection and parameters which affect disinfection of bacteria and viruses are reviewed, as are the more salient engineering aspects of ozonation systems as utilized in treating wastewaters.

Ozone in the Laundry Industry—Practical Experiences in the United Kingdom

Since the early 1990s, the use of ozone in many commercial and industrial laundering applications has been evolving rapidly. Ozone allows washing to be conducted using cold water, thereby saving considerable heat energy and water consumption. Additionally, ozone enhances the wash process, resulting in a significant reduction in detergent dosage and number of rinses, thus saving water. Ozone/cold water cycles are gentler to fabrics, thus extending linen life. Finally, ozone/cold water laundering is beneficial for effluents, resulting in reductions in COD (chemical oxygen demand). Microorganisms are destroyed effectively in ozone-wash waters, and washing and drying cycles are shorter, thus saving labor. In this paper, the authors describe some specific case studies at commercial laundering installations in the UK, whereby the users of ozone have reaped major benefits, including enhanced microorganism kills/inactivation and significant cost savings.

User Experiences with Ozone, Electrolytic Water (Active Water) and UV-C Light (Ventafresh Technology) in Production Processes and for Hygiene Maintenance in a Swiss Sushi Factory

In a sushi production factory in Vuadens, Switzerland, ozone, ultrasound, electrolyzed water, and UV (185 and 254 nm) radiation are employed to sanitize all production equipment and factory space, including incoming and cooled air, as well as to sanitize the sushi products themselves. Fish, vegetables and rice all are washed with electrolyzed water as ultrasound is applied. Sushi itself is disinfected prior to packaging by fumigation with ozone and UV radiation in a special UV Disinfection Tunnel. Packaging materials (film and trays) are disinfected with gaseous ozone and UV radiation. After sealing of the sushi packages with Modified Atmosphere Packaging (including additional oxygen), UV radiation again is applied in another, longer UV Disinfection Tunnel. This transforms about 12–14% of the oxygen remaining inside the packed tray to ozone, creating an ozone-containing atmosphere. By this Ventafresh technology, the shelf-life of sushi products increases from three to seven days. Plant ambient temperature is maintained at 3°C at all times during processing to provide additional improvement in microorganism control. Cost savings at Sushi are significant, but secondary – only one failure and the plant is shut down. Ventafresh is, at the very least, a technological insurance policy that allows the plant manager to sleep at night.

Wastewater Ozonation in the U.S.A. – History and Current Status - 1989

Abstract Wastewater ozonation has achieved its widest application in the United States of America in the past ten years. Many U.S. facilities designed in the 1970s have manifested significant operational and maintenance problems with the first generation application of ozone technology to wastewater treatment. These problems are reviewed and solutions recommended. The second generation facilities of the 1980s demonstrate higher levels of efficiency, reliability, and operability. The broad application of ozonation to wastewater treatment in the United States of America (U.S.) in the 1970s was carried out with little or no reference to the prior experience of the applications of ozone in the field of drinking water treatment attained in Europe.

The Chemical Reactions of Ozone and Their Role in Developing Improved Analytical Methods

Abstract Most methods for the determination of ozone have been developed by utilizing, with or without odifications, existing methods for chlorine determination. The problem with this approach is that ozone chemistry is very different from chlorine chemistry. We believe that a detailed understanding of the mechanism of ozone decomposition and the chemistry of the by-products is essential in order to develop selective methods forozone. This paper briefly describes the ozone decomposition mechanism and introduces the concept of an “Ideal Method. The indigo method is examined as an “Ideal method” and the automation of this method by Flow Injection is discussed.

Six years of ozone processing of fresh cut salad mixes.

Strickland Produce Inc., Nashville, TN, packages fresh cut salads in bags for the ready-to-eat market. Produce is sorted, cut, washed, packed in plastic bags and distributed under refrigeration. Flume water washes and transports products through the plant, and is recycled in a closed loop. Ozone was installed full-scale in 2000 for flume water treatment (200 gpm) and has provided significant improvement in plant product qualities plus savings in water, labor, and plant effluent costs for the past six years. With chlorine treatment alone, the flume water quickly became discolored, laden with organic residues, and needed to be replaced every 2–3 hours. With the ozone treatment, flume water is replaced once daily, allowing for at least a 60% flume water savings. Of even more significance are the labor savings resulting from less frequent changing of spent flume water. Costs for ozonation equipment were recovered in less than two years.

Fundamental Aspects of Ozone Chemistry in Recirculating Cooling Water Systems — Data Evaluation Needs

Abstract Proposed uses of ozone for stand-alone cooling water treatment raise critical questions as to what happens chemically. These questions are of more significance to industrial cooling water systems, which typically have higher temperatures and cooling ranges than do comfort cooling systems. When applying ozone to cooling waters, it is very important for the user to understand many fundamental aspects of ozone chemistry. For example, when ozone is added at water pH levels often encountered in cooling waters (≥ 8), it decomposes to form hydroxyl free radicals, which are stronger oxidizing agents than molecular ozone itself, but of microsecond half-life, and therefore are poor disinfectants. The presence of bicarbonate alkalinity, hardness, naturally occurring organics, bromide ion, and effects of pH levels on water quality parameters and molecular ozone, have pronounced effects on chemical reactions which occur when ozone is added to cooling waters. The authors review the fundamental chemistries invo...