Modern Methods for Wastewater Purification

  Nanotechnology has been of great importance in wastewater treatment to enhance treatment Efficiency and to increase water supply through safe use of unconventional water sources. Nano-particles are of a very lesser size like less than 100nm. Nano-particles have very high absorbing, interacting and reacting capabilities as its size is quite small with high proportion of atoms at surface. It can also be mixed with aqueous suspensions and can behave as colloid. The methods of synthesis as well as applications rely upon the field at which they are used. One of the main factor is larger surface area to volume ratio(S/V Ratio). Hence, this makes it able to react very quickly, the best example for this type is silver nano-particle. Various wastewater Treatment technologies like Coagulation, flocculation, bio-degradation, adsorption, ion-exchange, and advanced oxidation are the main techniques among which adsorption has been found to be the most energy efficient and cost-effective...

One of the best techniques applied for the decontamination of wastewaters from dyes and heavy metals is by the use of potential of nanomaterials as nanoadsorbents. Nanomaterials hold a series of distinctive physical and chemical properties. One thing very important about nanomaterials is that most of the atoms which have high chemical activity and adsorption capacity are situated on the surface of the nanomaterials. Various nanoadsorbents were elsewhere overviewed in treating contaminated water; their advantages and drawbacks in such applications were evaluated. The implications of nanoadsorbents to public health and their way forward for facilitating environmental sustainability are great as well.   Among these the iron oxide nanoadsorbents are cost-effective adsorbents that provide high adsorption capacity, rapid adsorption rate and simple separation and regeneration. A lot of analysts have been using nanoparticles like adsorbents in order to get rid of water pollutants...

 Wastewaters are waterborne solids and liquids discharged into sewers that represent the wastes of community life. Wastewater includes dissolved and suspended organic solids, which are “putrescible” or biologically decomposable. Two general categories of wastewaters, not entirely separable, are recognized: domestic and industrial. Wastewater treatment is a process in which the solids in wastewater are partially removed and partially changed by decomposition from highly complex, putrescible, organic solids to mineral or relatively stable organic solids.  Primary and secondary treatment removes the majority of BOD and suspended solids found in wastewaters. However, in an increasing number of cases this level of treatment has proved to be insufficient to protect the receiving waters or to provide reusable water for industrial and/or domestic recycling. Thus, additional treatment steps have been added to wastewater treatment plants to provide for further organic and solids removal...

 A type of treatment that uses substances made from living organisms to treat disease. These substances may occur naturally in the body or may be made in the laboratory. In cancer, some biological therapies stimulate or suppress the immune system to help the body fight cancer. Biological treatment processes in wetland systems depend on supplying colonies of micro-organisms with optimum quantities of air and nutrients to achieve the same reactions that occur in natural self-purification processes, at a maximum benefit to cost ratio. The three changes that occur during self-purification include coagulation of colloidal solids passing through the primary sedimentation stage; oxidation of carbon, hydrogen, nitrogen, and phosphorus; and nitrification. The basic biological treatment processes used in the system include waste stabilization ponds and constructed wetland systems, trickling (or percolating) filter systems, and activated sludge systems. An aerobic stabilization pond is a la...

This water filtration innovation is an acoustically driven molecular sieve embedded with small-diameter carbon nanotubes. Turning the idea of filtration on its head, this technology pushes water away from contaminants, rather than removing contaminants from water. Water enters the device and first contacts the filter matrix, which can be made of polymer, ceramic, or metallic compounds, depending on end-use requirements. Carbon nanotubes within the matrix allow only water molecules to pass through, leaving behind any larger molecules and contaminants. The unique aspect of the technology is its use of acoustics to help drive water through the filter. An oscillator circuit attached to the filter matrix propagates acoustic vibration, further causing water molecules to de-bond and move through the filter. This use of acoustics also eliminates dependence on gravity (and thus filter orientation) to move water through the device. When water exiting the system diminishes to a pre-determin...

Bioaugmentation  is the practice of adding cultured microorganisms into the subsurface for the purpose of biodegrading specific soil and groundwater contaminants.  In many cases, cultured microorganisms used for bioaugmentation are “specialists” in degrading specific target contaminants. For example, some microbes may be able to degrade the chlorinated compounds cis-1,2 dichloroethylene (cDCE) and vinyl chloride (VC) more quickly than the naturally-occurring microbial community at a particular site. As a result, the remediation community has shifted toward a more prescriptive approach with the use of bioaugmentation to accelerate the reductive dechlorination process, achieve remediation targets, and realize cost savings. Bioaugmentation is commonly used in  municipal wastewater treatment to restart activated sludge bioreactors. Most cultures available contain microbial cultures, already containing all necessary microorganisms( B.licheniformis ,  B.th...

  Water pollutants have huge impacts on the entire living systems including terrestrial, aquatic, and aerial flora and fauna. In addition to conventional priority, and newly emerging micro/nano-pollutants, increasing global warming and consequent climate changes are posing major threats to the fresh water availability. Global warming and climate change are constantly increasing the salinity level of both land and sea water, dwindling the availability of existing fresh water for household, agriculture and industry. This has made it urgent to invent an appropriate water treatment technology that not only removes macro-, micro- and nano-pollutants but also desalinates water to a significant extent. Tip-functionalized nonpolar interior home of carbon nanotubes (CNTs) provides strong invitation to polar water molecules and rejects salts and pollutants. Low energy consumption, antifouling and self-cleaning functions have made CNT membranes extraordinary over the conventional ones. We com...

  As we know that nanotechnology is a new science, the way of filtering at the nanoscale level with the use of a membrane doesn’t seem as anything brand new. It’s a biomimetic process Xeroxed up directly from the nature.The living cells use a structure of the nanomembrane for functioning. The processes include the conveying of salts from blood and also the shifting of oxygen to and carbon dioxide from the cells. Nanomembranes are basically made from the organic polymers based on nanocomposites having a thickness less than 100nm. Such nanomembranes include organic polymers amalgamated  with a mesh of silica nanoparticles. The size of holes in the mesh restricts or allows the passage of different sized molecules.   A special focus in BioSense research is the development and functionalization of nanomembranes for sensing applications. Due to very large aspect ratio of nanomembranes, such sensors imply very large active areas for a small volume, resulting in h...