Physical treatment technologies

Table 4 allows a generic identification of the various technology options suitable for treating wastes based on their hazardous characteristics and physical form Table 4 also identifies the kinds of data which must be collected to perform a valid evaluation of those technologies. The physical treatment data needs for different media shown in Table 5 are typically required in addition to those presented in Table 4. 

Various treatment technologies are used at the iron and steel plant for recycle system water treatment prior to recycle and reuse, or end-of-pipe wastewater treatment prior to discharge to surface water or a POTW. The physical/chemical treatment technologies extensively used include equalization, tar removal, free and fixed ammonia stripping, cooling technologies, cyanide treatment technologies,... 

In situ groundwater treatment is an alternative to the conventional pump-and-treat methods. In situ treatment uses biological or chemical agents or physical manipulations that degrade, remove, or immobilize contaminants. In situ treatment technologies can usually treat both contaminated groundwater and soil. In many instances a combination of in situ and aboveground treatment will achieve the most cost-effective treatment at an uncontrolled waste site. 

Physical color removal technologies that were reported in the literature include adsorption, chemical precipitation, and membrane separation [14—17]. The high cost and disposal problems have opened the door for further investigation of new techniques. The inability of biological treatment processes in degrading azo dye compounds makes physical treatment a necessary stage prior to biotreatment in... 

In September 1991, CPE VIII was convened in Lublin, Poland. The technical presentations were original and informative, with the major topics being chemical/physical/biological treatment technologies, monitoring, modeling, and risk assessment. 

It is expected that in the very near future, the application of closed water loops will show an intensive growth, strongly supported by the further development of separate treatment technologies such as anaerobic treatment, membrane bioreactors, advanced biofilm processes, membrane separation processes, advanced precipitation processes for recovery of nutrients, selective separation processes for recovery of heavy metals, advanced oxidation processes, selective adsorption processes, advanced processes for demineralisation, and physical/chemical processes which can be applied at elevated temperature. 

The past two decades have shown an increasing interest in advanced physical-chemical processes for wastewater treatment12. There are several reasons for this increasing interest. First, with conventional aerobic and anaerobic biological wastewater treatment technologies many industrial... 

Brown, S. G., 1998, Physical Containment of a DNAPL Source In Designing and Applying Treatment Technologies, Remediation of Chlorinated and Recalcitrant Compounds (edited by G. B. Wickramanayake and R. E. Hinchee), Battelle Press, Columbus, OH, pp. 115-120. 

Stabilization/solidification (S/S) is a proven technology for the in sitn or ex situ treatment of hazardous wastes and hazardous waste sites. It uses additives or processes to physically and/or chemically immobilize the hazardous constituents of contaminated soils, sludges, sediments, or even hquid wastes. The object of this technology is to prevent the migration of contaminants into the environment by forming a sohd mass. Contaminants are trapped and immobilized within the existing medium, rather than removed via chemical or physical treatments. 

This type of technology differs from most other remediation technologies is that the goal is to trap and immobilize contaminants within the existing medium, rather than trying to remove them via chemical or physical treatments. 

A wide variety of treatment technologies to reduce the volume, change the physical or chemical form (e.g., incineration, solidification of a liquid waste, neutralization of acidic or basic waste), and suitably package the waste for subsequent management steps. 

Solidification/stabilization is a promising treatment technology for containing and immobilizing dredged material contaminants within a disposal site. While solidification/stabilization is not a solution to every disposal problem, the technology offers improved physical characteristics that reduce the accessibility of water to contaminated solids and reduced leachability for many contaminants. Leaching tests must be able to determine the (a) compounds that can be released from the waste (b) maximum concentration of these compounds in the leachate (c) quantities released per unit mass of waste (d) release rate of these compounds and (e) effects of a co-disposal of the waste. 

The most important water treatment technologies are summarized in Fig. 5-6. Depending on the source and on the water quahty, either mechanical, biological, physical, thermal, or chemical processes or their combinations may be applied. Photochemical AOPs and AOTs are subordinated to chemical processes, mainly because the current technological versions of photochemical wastewater remediation are dependent on the addition of auxihary oxidants, such as hydrogen peroxide, ozone or special catalysts such as titanium dioxide. Photochemical AOPs are attractive alternatives to non-destructive physical water treatment processes, for example adsorption, air stripping or desorption and membrane processes. The last merely transport contaminants from one phase to another, whereas the former are able to minerahze organic water contaminants (cf. Chapter 1). 

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