The disposal of untreated wastewater coming from the industries into the water bodies will pollute the water bodies because of its high concentrations. So, the wastewater produced from the industry should be treated properly to meet the permissible limits given by central and state pollution control boards. Therefore it is necessary to treat the wastewater properly with the help of an appropriate treatment plant. However, the treatment plant even though properly planned may not work satisfactory because of several reasons. Hence, it is essential to evaluate the treatment plant considering individual treatment unit in the entire treatment flow. In the present work emphasis has been given to the study of the performance of treatment facilities because of its importance in the conventional treatment of wastewater. Hence, the literature review related to the evaluation of the entire treatment process along with biological treatment process particularly suspended growth process Activated Sludge Process (ASP), attached growth process Trickling Filter (TF) and a combination of the both suspended and attached growth process Hybrid Reactor (HR) is presented in the following sections of this chapter.
2.2 REVIEWED OF LITERATURE ON ACTIVATED SLUDGE PROCESS
In suspended growth processes, the microorganisms responsible for the treatment of wastewater are maintained in liquid suspension by appropriate mixing methods. Many suspended growth process used in municipal and industrial wastewater
Environmental Protection Agency (EPA) described the general treatment of wastewater and its two basic stages, primary and secondary. In the primary treatment most solids are caught in a screen, then the sewage goes to a grit chamber to settle small pieces of debris at the bottom, then through the sedimentation tank. Afterwards, secondary treatment removes a majority of the organic matter, eventually being chlorinated before reaching an effluent (EPA, 1998).
Mostly, wastewaters are usually perilous and unhealthy for human beings, aquatic plants and animals in addition to responsible for the deterioration of environment so it should be treated earlier to its disposal into the aquatic medium and land surfaces. After secondary treatment of domestic and agro-industrial polluted water still discharges large amounts of phosphorus and nitrogen. Such increased percentage of nutrients leads to eutrophication of lakes, rivers, ponds and seas which also leads to augmentation of algal bloom (Lau et al., 1997; Trepanier et al., 2002) and throwing away of wastewaters produces a steady threat to fading of natural resources of fresh water on worldwide (Montaigne and Essick, 2002). Under the extreme nutrients in the wastewater, such as
First, control over the discharge can take place at the point of generation within the plant itself. Second, the polluted water can be sent to water treatment plants before it is released into the surrounding water sources. Third, the waste water can be treated within the plant and recycled again, or treated in the plant and released.
In conclusion, a treatment can purify drinking water largely than city treatment plants and distillation, this option, made a successful at removing some contaminants, it is expensive and wasteful, but it is safe. The perfect technology for treating water and removing unwanted contaminants is water filtration. Water filters, when compared to any other water treatment option, will remove the contaminants and afford safer, healthier drinking water. Tap water, beside on not being expensive and highly available as a main drinking water, is under the government organization as municipal
Thirdly, the proceeding water treatment step involves coagulation and flocculation. The objective of this step is to produce particles of a size that can be easily removed by settlement and filtration. Coagulation destabilizes the colloidal particles followed by flocculation whereby larger particles are formed from small particles through collisions. Conley and Evers (as cited in Hendricks, 2006, p. 277) described coagulation as a process that reduces the surface charge
This report provides analysis and evaluation of a newly designed wastewater treatment facility for Sand Valley, Nevada. Analysis will include Biological Oxygen Demand (BOD) along with total, volatile, and fixed suspended solids. Methods for analysis will include the Winkler Test for BOD and a Hatch test for the suspend solids.
Public Education. Government at all levels should sensitize the populace as to the essence of wastewater management and how individual behaviour impact the process.
All heavy metals were detectable in the wastewater samples with a frequency of occurrence about 100% and only Pb was detected at lower frequency (90%). [9] reported that the phase distribution of individual metals exhibited only small change during the treatment process with a slight progressive increase of the dissolved phase of some metals after each treatment step. [10] reported in their study that the sorption of copper and cadmium ions using activated carbon, waste materials (such as compost, cellulose pulp waste and anaerobic sludge) as sorbent. According to the study the copper being preferentially adsorbed by all materials the exception of anaerobic sludge [11] [12].
Increasing modernization in urban and rural areas led to tremendous growth in industrial activities. Untreated and partially treated effluents from industries and hospitals were discharged into the aquatic environment. Due to these activities
It can be concluded that mixed primary and secondary iron nanoparticles were synthesized in Mt and PVP involved borohydride reduction system. In addition, the nanoparticles contained an iron oxide-coated α-Fe core and a PVP surface layer. Also, the clay-polymer interactions made PVP not only adsorb on the external surface but also intercalate into the interlayer space of Mt particles, developing a polymer barrier on the clay mineral surfaces. Due to the barrier-related steric hindrances and/or alkaline pH-derived electrostatic repulsions, the clay mineral particles built a card-house flocculation structure, which after suitable washing and drying can convert to a semi-card-house form in dry products. [2]
Assessment of Water Quality in relation to some Physico-chemical parameters in Araga pond of Thirthahalli Taluk, Shivamogga, Karnataka.
Waste water treatment plants consists on a series of processes and units to produce a specific effluent of known composition and flow rate. These treatments are essential to deal with domestic, industrial and agricultural contaminations and pollutants mainly considering solids of organic nature. The main focus on this design will be organic compounds in the domestic waste water – BOD (Biochemical Oxygen Demand) and TSS (Total Suspended Solids). Based on the Royal Commission for UK and Ireland the concentrations of effluents to be disposed on receiving water are 20mg/L for BOD5 and 30mg/L for TSS as theses parameters apparently would not cause any harm and will not be favourable for other process such as eutrophication. Considering that Severodvinsk is situated close to the Dvina River and White Sea these concentrations does not need to be highly restricted once that there is plenty of water available for further dilutions. Is important to have in mind that low parameters involves high investments in processes and equipments.
In suspended growth processes, the microorganisms responsible for the treatment of wastewater are maintained in liquid suspension by appropriate mixing methods. Many suspended growth process
Sludge could be produce in many ways, it can be from waste settlement to the dry process. Brick is one of the flexible product that gain attention from researcher to be incorporated with different type of sludge material such as waste water sludge, water treatment sludge, marble sludge, effluent treatment plants (textile industry) sludge and arsenic contaminated sludge.
This report highlights the significance of engineers in providing some of the world’s most critical developments: piped infrastructure and treatment plants. It is made apparent throughout the report that providing potable water and sanitation, via these piped infrastructures and treatment plants, is vital for tackling some of the biggest challenges the world faces. This includes tackling poverty, pollution and water-borne diseases. Some of the techniques used to treat water and sewerage is briefly covered within this report: ultrafiltration (UF) membrane systems. The restrictions of providing these infrastructures and techniques - such as financials - in developing countries is revealed; thus, emphasising the importance of providing aid to less economically developed countries (LEDC’s) so systems can be implemented, helping tackle the millennium development goals. It is concluded that engineers are fundamental in humanities developments, not only by maintaining systems already in place, but providing solutions to challenges which are always arising.