Wastewater treatment advantages

Ammonium Ion Removal. A fixed-bed molecular-sieve ion-exchange process has been commercialized for the removal of ammonium ions from secondary wastewater treatment effluents. This application takes advantage of the superior selectivity of molecular-sieve ion exchangers for ammonium ions. The first plants employed clinoptilolite as a potentially low cost material because of its availability in natural deposits. The bed is regenerated with a lime-salt solution that can be reused after the ammonia is removed by pH adjustment and air stripping. The ammonia is subsequentiy removed from the air stream by acid scmbbing. 

RO, primarily used ia the dairy iadustry, is expanding iato other areas of food processiag. RO can be used for a variety of operations, ranging from wastewater treatment and material recovery to clarification and concentration. Material recovery is advantageous for two reasons. By recovering valuable products, eg, proteias, from waste streams, profits can be iacreased while costs for waste disposal decreased. An excellent review of the different apphcations ofRO ia food processiag is available (9). 

In developing countries, additional advantages of using CWs can be obtained. They may provide economic benefits and could encourage small communities to maintain natural wastewater treatment systems. The production of plant biomass can provide economic returns to communities through production of biogas, animal feed, compost, and fiber for paper according to the type of pollutant.46... 

Section 27.8 summarizes the feasibility and advantages of an improved biological wastewater treatment system involving the use of secondary flotation clarification. 

For waste treatment rather than fermentation for product formation, again few examples of process economics exist in the literature. Those that do, favor fluidization. Badot et al. (1994) described an industrial prototype fluidized bed reactor that competed favorably on an economical basis with activated sludge processes for treating carbon pollution and was estimated to be economically comparable to fixed bed processes for denitrification. Schneeberg (1994) described the successful and economically-sound implementation of fluidization as an upgrade to an existing wastewater treatment plant. The restricted space available for extension of the wastewater plant made fluidization particularly advantageous in this case. 

In the aforementioned closed loop water system the polluted process water is purified completely in one wastewater treatment scenario. Only one type of process water is produced for reuse. In practise several types of process water are needed, and also several types of polluted wastewater streams are produced. This is schematically shown in Figure 2. In that case it can be advantageous in technical, economic and environmental respects to include several closed loop water systems within one production line. 

According to the vendor, Mixflo has the following advantages in wastewater treatment applications ... 

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