Figure 1: Simple batch homogenous reactor. [Fogler, H. S. (2010, November 22). Essentials of Chemical Reaction Engineering: Mole Balances. Retrieved April 24, 2014, from Pearson Education: http://www.informit.com/articles/article.aspx?p=1652026&seqNum=3] Characteristics • Batch reactor normally deals with chemicals or biological reaction. • Two holes in the top of the tank, to charge the reactant and to transfer out the reactant. • Typical batch reactor equipped with agitator as stirring mechanism to increase effectiveness of reaction. • Operating step of batch reactor: 1. The reactor is initially charged with reactants such as chemical substances. 2. The operating condition is adjusted to meet the effective operating condition such as its content is heated up to the optimum temperature of the reaction for a specific period of time for the reaction to take place until the reaction completed. 3. Shutting down of reactor in which the content (product) is cooled down. 4. Emptying the reactor by transferring out the product. 5. Cleaning of the reactor for the next batch operation (Tsai & Tin, 1996). • There is no addition of feed or removal of product along the reaction is carried out (Blevins, 20014). • The temperature of tank is easily adjustable by using jacket (Batch Reactors, 2000). Applications • Wastewater treatment o Activate sludge system: Using natural biological such bacteria in which they help to remove contaminant. o The bacteria and wastewater is mixed in an aeration tank and therefore the contaminants are removed by action of sorption and series of breakdown by the bacteria. o Sequencing Batch Reactors (SBR): Applied activated sludge treatment in the reactor in which all of the treatment process is carried out in a reactor tank without presence of clarifiers. o Batch mode operation and each batch are sequenced through a series of treatment stages (Arora, n.d). o Typical SBR Process: The tank is filled with wastewater Mixed with activated sludge where tha waste water contain source of food to the microbes in the activated sludge. Presence of waste water creating an environment favorable for biochemical reaction to take place. Wastewater no longer added into the reactor. Addition of air and mechanical mixing to enchance the growth of bacteria and ficilitate subsequent waste reduction Biological reaction is carried out until the required degree of treatment is achieved Mixing and aeration stop Activated sludge settle as a flocculant mass. Two layers is formed, the sludge mass layer and clear supernatant layer. Clarified effluent (supernatant) is discharged Removal/ wasting of activated sludge during this stage if the amount of activated sludge presence in excess. Figure 2: Typical SBR Process [Typical SBR Process [Arora, S. (n.d). Sequencing Batch Reactors Wastewater Treatment. Retrieved April 25, 2014, from http://www.env.gov.nl.ca/env/waterres/training/aww/08_susheel_sequencing_batch_reactors_in_wastewater_treatment.pdf] • Pharmaceutical production:
It combines this two-... ... middle of paper ... ... rogen In Wastewater To Protect A Region's Waterways." BioCycle 44 (2003): 18.
Sterilization process is done for the complete elimination of all microorganisms that could potentially be a contaminant and lead to occurrences of hazards. (Chi, 1993) Sterilization is a process defined by killing all the living microorganisms that includes bacteria and spores. This process can be done chemically, physically and by means of physiochemical methods. (Soper & Davies, 1990)There are chemicals used in these processes to ensure all microorganisms no longer exist and they are known as sterilizing agents and are called chemisterilants. The result of sterilization often depends on the type of substance being sterilized and the conditions made to suitably sterilize it. (Soper & Davies, 1990)
Stephenson, R., & Blackburn, J. J. (1998). The Industrial Wastewater Systems Handbook. New York: Lewis Publishers.
Comment on class result with respect to differences in filter types, differences in filter assemblies, and overall on the confidence you would have in using this type of sterilisation process in preparation of pharmaceutical products. List the factors that may cause contamination during filtration. (20 marks)
There are several different levels of purification, so the water can be reused for diverse purposes. Through only low levels of purifications treatments water can be reused for landscape, golf courses, and agricultural purposes. After intensive processing waste water can be used to supplement our drinking water supply. At the beginning this process the water is filtered to remove any large pieces in the water. Following that the water is then allowed to sit to and let small items sink to the bottom. For the items in the water that were not filtered out, or were able to sink are filtered out through the use of chemical reactions. The chemical processes used are called flocculation and coagulation. This process is used to clump together the particles that were to light to sink on their own. Some common compounds that are used to carry out these processes are aluminum sulfate, poly-aluminum chloride, ferric chloride, and ferric sulfate. During this process the chemical compounds react with the ions in the water to create precipitates; when the precipitate forms it will gather all of the particles in the water that were not able to sink on their own, and then both of the materials will settle to the bottom of the
Yasui H. and Shibata M., 1994. An innovative approach to reduce excess sludge production in the activated sludge process. Water Sci. Technol. 30, 11-20.
The formation of the biofilm depends on factors like the type of surface used, presence of polymeric molecules on the surface and cell-cell interactions. Wastewater is passed through the surfaces on which the biofilms are attached. The microorganisms in the biofilm utilize the organic matter present in the wastewater and subsequently, the biofilms grow. There are four predominant reactor types that utilize this technology. Trickling Filters (TFs), Rotating Biological Contactor (RBC) Systems, Constructed Wetlands and Membrane Bioreactors (MBRs) (Sehar & Naz, 2016).
...sis. At this stage the treatment plant has the wastewater pumped through membranes. This process eliminates viruses, bacteria, and protozoa that are in the wastewater. Advanced Oxidation happens next in the treatment process. UV and or ozone and hydrogen peroxide and used to further disinfect and remove contaminants from the wastewater. The last step is called Fresh Water Blend. As stated in the name of the process Freshwater is now blended with the wastewater. Either the water is blended with surface water reservoirs or added to groundwater, where this water can remain in these reservoirs for an average of 6 months to be further purified by natural processes. Once this water is taken from the groundwater or reservoir is goes through the same standard water purification process all drinking water undergoes to meet the U.S. Environmental Protection Agency standards.
A precise system, of which must be compliant according to government standards, is critical to maintain low levels of waste that are returned to neighboring water systems after treatment. Phase one of waste water treatment begins in the home, local businesses and community. Waste water from these buildings and surrounding areas travel through a pipe, or sewer which is sloped downward, and with the assistance of gravity, travels toward the waste water treatment plant. However, in larger communities or communities with unevenly leveled terrain, waste water cannot keep getting deeper to rely on gravity to transport the waste water and must be pumped up with the assistance of a lift station so it may continue to travel to the water treatment plant. Once the waste water arrives at the waste water treatment plant, the first step is the removal of large debris such as diapers, underwear or other non-biological substances or products.
However, even though many biofilms are harmful, there are many helpful biofilms, too. One of which is the biofilm that is used in sewage and is very effective at treating environmental wastes. People rely on these biofilms to remove contaminants from the water. Another example of a beneficial biofilm is one that can be used to produce a greatly diverse amount of biochemicals that are then purified and utilized for public good, including medicines, food additives, or chemical additives for cleaning products. These are two examples of helpful biofilms.
What is sewage you ask, the dictionaries defines sewage as; the waste matter from domestic, commercial, and industrial establishment carried off in sewers. When waste matter enters water, the resulting product is called sewage or wastewater. Garbage is defined as; animal or household refuse Sewage is stored in sewers. Then treated or in a sense recycled. Raw sewage includes waterborne waste from sinks, toilets, and industrial processes. Treatment of the sewage is required before it can be safely buried, used, or released back into local water systems. In a treatment plant, the waste is passed through a series of screens, chambers, and chemical processes to reduce its bulk and toxicity. The three general phases of treatment are primary, secondary, and tertiary. During primary treatment, a large percentage of the suspended solids and inorganic material is removed from the sewage. The focus of secondary treatment is reducing organic material by accelerating natural biological processes. Tertiary treatment is necessary when the water will be reused; 99 percent of solids are removed and various chemical processes are used to ensure the water is as free from impurity as possible.
The world as we know has been polluted, it’s air and water. NASA created a water purification system that could purify used water over and over again. Two of the main things the water purification system does is remove any bacteria and viruses in the water. One of the ways NASA does this is, they would use a device that would release water filled with negatively charged silver atoms. These silver atoms would then hold on to the bacteria and destroy the bacteria. NASA used to have water shipments sent on to the spaceships but they thought they needed to be more eco, so they decided to purify the water. We release such as sweat, tears and urine and the system is able to recycle 95% of the water, but liquids such as urine are harder to recycle. The urine is given chromium dioxide and sulfuric acid to kill microbes and stop chemical reactions from happening that creates odor. Then the water is put in a distillation cylinder that spins and the distiller then it creates the heat that ...
Step 1 is repeated by using different yeast strains, a pet 1 and M240 into all 6 conical
The catalytic process occurs at lower temperature anf offers higher selectivity but requires frequent regeneration of the catalyst. Then, the products are cooled and introduced into a pair of separators which separate the unreacted hydrogen. The unreacted hydrogen is compressed and recycle back to the feed and reactor. The products that leaving the separators are heated before introduced into a distillation column which the toluene is separated from the stream and recycle back to the...
The terms secondary and primary treatment have been used to basically describe a degree of treatment; for example, biological wastewater treatment and settling. Tertiary treatment has been regarded as different from secondary and is the advanced one. It comprises of the use of sand filters to separate the solid particles from the wastewater. Tertiary treatment has also been regarded as the treatment involved to remove plant nutrients, primarily nitrogen and phosphorous.