摘要:

Natural Organic Matter (N0M) was isolated and extracted from a moderately-colored surface water, then fractionated using hydrophobic and ion exchangeresins into eight groups. Each was subjected to batch ozonation, and the rateof loss of ozone was measured. Then, selected fractions were analyzed forchanges in functional group content, molecular size and hydrophobicity; somewere further fractionated by size prior to functional group analysis. Fulvicacids and humic acids were the most reactive. These groups also showed thegreatest change in carboxyl group content and hydrophobicity. The results arediscussed with respect to impacts on coagulation. Although hydrophilicneutrals were of low to moderate reactivity, they showed the greatest promisefor improved coagulation following preozonation.

ISSN:0191-9512    

DOI:10.1080/01919519408552415

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

In this note, we review and explain which key parameters of composition of awater are required for quantifying its physical and chemical properties withrespect to ozonation reactions. The quality of the water, however, often has to be characterized beyond such analytical data. Additional parametersinclude an operationally defined rate with which added ozone is depleted (seePart II, following this paper) and by the parameters which characterize theconsumption of OH radicals produced as secondary oxidants when ozonedecomposes (see Part III, in preparation). The present series of notes shouldstimulate discussions on the selection of a minimum set of information andlead to guidelines on data requirements for ozonation processes.

ISSN:0191-9512    

DOI:10.1080/01919519408552416

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The lifetime value of ozone in a water is one of the key parameters for describing the characteristics of a water considering an ozonation process and for planning, optimizing, and steadily adapting the ozonation process. This lifetime is highly sensitive with respect to the chemical composition of the water. Interferences of different radical-type chain reactions make it difficultto predict it solely from analytical characterizations. The waters with respect to the lifetime of ozone, therefore, have to be characterized by direct laboratory experiments. However, because the half-life times depend on the type of operation used for the measurement, it is appropriate to formulate corresponding standardized guidelines that allow comparison whenever the responses of different waters have to be compared, and whenever characterizations have to be followed during the decades during which a water utility applies a process.

ISSN:0191-9512    

DOI:10.1080/01919519408552417

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

This article presents a simple, rapid and efficient laboratory method permittingone to simulate the effects of ozonation (OZOTEST method) or of an oxidation by combined ozone/hydrogen peroxide (PEROXOTEST method) on an industrialscale. A critical analysis of the method is made (ozone transfer, validity of the results) and several practical applications are submitted for consideration (ozone demand, oxidation of atrazine and the DOC).

ISSN:0191-9512    

DOI:10.1080/01919519408552418

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

During water treatment, ozonation of waters containing bromide ion producesboth organic and inorganic disinfection byproducts. Bromide ion concentrations in U.S. waters range from 0.01 to 2 mg/L (Krasner, 1989). Bromoformand dibromoacetic acid (DBAA) are the major organic byproducts and bromateion is the major inorganic byproduct derived from ozonation. Bromoform is a known carcinogen and the existence of bromate ion in water supplies also is of public health concern (Lykins, 1986). Bromate ion causes renal failure and hearing loss in laboratory animals and in human beings (Kruithof, 1992). The provisional guideline for bromate ion as proposed by the World Health Organization is 25 pg/L and may be exceeded in water treatment processesusing ozone. Also draft drinking water regulations in the U.S. will specify a maximum contaminant level (MCL) of 10 µg/L for bromate ion and a bestavailable treatment (BAT) of pH adjustment.

ISSN:0191-9512    

DOI:10.1080/01919519408552419

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0191-9512    

DOI:10.1080/01919519408552420

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0191-9512    

DOI:10.1080/01919519408552414

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor