Drinking water treatment systems

MTBE Performance Summary for 12 Ongoing Drinking Water Treatment Systems... 

PUMP-AND-TREAT AND DRINKING WATER TREATMENT SYSTEMS... 

Coarse (dP = 50-100 pm) porous disks are the most frequently applied diffusers in large-scale drinking water treatment systems (Masschelein, 1994). They are seldom used in industrial waste water treatment applications. The reason is that blocking or clogging can easily occur, e. g. by means of precipitation of chemicals, like carbonates, aluminum or ferrous oxides, manganese oxides, calcium oxalate or organic polymers. This is also valid for ceramic filter tubes, which are sometimes used as mass transfer systems in drinking water applications. 

Jekel M R (1982) Biological Drinking Water Treatment System Involving Ozone, Chapter 10 151-175 in Handbook of Ozone Technology and Applications Vol. II, Ozone for Drinking Water Treatment Rice R G and Netzer A (Editors), Ann Arbor Science, Ann Arbor MI. 

Point-of-Entry Drinking Water Treatment Systems for Superfund Applications... 

It is critical in either case to understand and evaluate the adsorption interactions in the context of drinking water treatment systems. Activated carbons are prepared from different precursors and used in a wide range of industries. Their preparation, structure, and applications were reviewed in... 

Because of their suitability for disinfection and oxidation (e.g., taste and odor control, micropollutant removal), chemical oxidants are commonly used in water treatment processes. In drinking water treatment systems, the oxidants coimnonly used are chlorine, chlorine dioxide, chloramines, and ozone. 

There is a great deal of interest in the application of fluorescence techniques for the monitoring of DOM in drinking water and drinking water treatment systems. Early research dealt with the influence of chlorination and oxidation of NOM and the prediction... 

Hydrogen peroxide is used by some water treatment systems to remove the disagreeable odor of sulfides in drinking water. It is available commercially in a 20.0% by mass aqueous solution. What is the mole fraction of H2Q2 ... 

NDMA (and other nitrosamines) can dramatically increase in concentration in distribution systems (relative to finished water at the drinking water-treatment plant). For example, an initial level of 67 ng/L in drinking water-treatment plant effluent was shown to increase to 180 ng/L in the distribution system [53]. As a result, measurements taken at water-treatment plants may substantially underestimate the public s exposure to this carcinogen. 

Xi C, Zhang Y, Marrs CF et al (2009) Prevalence of antibiotic resistance in drinking water treatment and distribution systems. Appl Environ Microbiol 75(17) 5714—5718... 

Chlorine dioxide is added to drinking water as a disinfectant in some municipal water treatment systems in the United States. In 1995, 5. 1% of community water treatment systems in the United States reported that chlorine dioxide was used (Hoehn et al. 2000). This would translate to about 12 million people who may be exposed to chlorine dioxide and chlorite ions in the United States. However, the total number of people exposed will be higher if smaller facilities (i.e., those serving <50,000 people) are also included in this value. 

Since reaction mechanisms and experimental observations are not independent of the system in which they are made, the experimental set-up and how the experiment is run affect the outcome. That means that it must be clear how equipment and procedures affect the outcome when they are chosen. It also means that experimental set-ups and procedures from drinking water treatment cannot be applied on waste water without appropriate evaluation and vice versa. In general, an experimental set-up consists of an ozone generator, reactor, flow meters and on-line analysis of at least the influent and effluent ozone gas concentrations and ambient air monitor (Figure 2-1). Each set-up will be tailored to the experimental goals and the resources available. 

Ozone is applied in three-phase systems where a selective ozone reaction, oxidation of residual compounds and/or enhancement of biodegradability is required. It can be used to treat drinking water and waste water, as well as gaseous or solid wastes. Especially in drinking water treatment full-scale applications are common, e. g. for particle removal and disinfection, while in waste water treatment sludge ozonation and the use of catalyst in AOP have been applied occasionally. Current research areas for three-phase ozonation include soil treatment and oxidative regeneration of adsorbers. Ozonation in water-solvent systems is seldom studied on the lab-scale and seems favorable only in special cases. In general, potential still exists for new developments and improvements in ozone applications for gas/watcr/solvent and gas/waler/solid systems. 

As the quality of drinking water sources gets worse, the methods of water treatment or the traditional water treatment systems need to be modernized. Pressure-driven membrane systems such as reverse osmosis (RO), nanofiltration (NF) and ultrafiltration (UF) and electric-driven membrane system such as... 

---