Hydraulics Distribution And Treatment

Significance of the Project

Discuss about the Hydraulics Distribution and Treatment.

Wastewater is water that is no longer suitable for use or that which is no longer needed. Wastewater treatment defines the process by which wastewater is changed to bilge water which is then usable back to the environment (Abraham, 2014).  Wastewater results from various activities among them bathing, using the toilet, washing and rainwater runoff. The contaminants in wastewater include bacteria, chemicals among other toxins. The main objective of wastewater treatment is enabling the disposal of both human and industrial effluents without posing a threat to the human health or creating an unacceptable damage to the natural environment.  Wastewater treatment thus aims at lowering the levels of contaminants to acceptable standards that makes the water safe for discharge backs into the natural environment.

Wastewater treatment plants exist in two categories: biological wastewater treatment plant and chemical or physical wastewater treatment plant (Fenchel, 2012). In biological wastewater treatment plant, biological matter and bacteria are used in the treatment of the contaminated water. These biological matter and bacteria break down waster matter and thus facilitating their elimination. On the other hand, physical wastewater treatment makes use of chemical reactions as well as physical process in the execution of the wastewater treatment process.  Wastewater from business premises and households are best treated using biological wastewater treatment plants while wastewater from industries, manufacturing firms and factories mostly adopt physical wastewater treatment plants in the treatment of their effluents (Ashton Acton, 2013). This is attributed to the fact that wastewater discharged from these premises contain chemicals besides other toxins which may have a large negative impact on the natural environment.

• Establish alternatives to wastewater treatment of both industrial and domestic waste water
• Explore through literature review of the various scholarly articles treatment of wastewater containing hydrogen sulfide, sources of hydrogen sulfide in wastewater and the aeration process and the various types or techniques of aeration
• Conduct an experiment on how VFD can be used in the wastewater treatment process
• Conduct an experiment on how batch process is used in wastewater treatment and the make comparison between the findings from the two experiments(Aziz, 2015)
• Recommend after the experiments, the most appropriate method that can be used in wastewater treatment based on conclusions from the outcomes of the experiment

Wastewater treatment remains a global challenge that affects systems varying from small domestic sewer systems to complex and sophisticated industrial systems. Various methods are available and have been deployed in the treatment of wastewater to ensure that the waste released from the various systems is not only harmless to the human population but also friendly to the natural environment (Federation, 2012). Each of the techniques and approaches that are used in wastewater treatment has challenges, shortcomings and weaknesses that in the long run reduce their efficiency and effectiveness as techniques for treatment of wastewater. This project is thus a presentation of a development that would see most of the challenges and shortcomings of the preceding techniques significantly addressed. The project aims at determining the effectiveness of the used of VFD technology in the wastewater treatment system. Being a new technology, the incorporation of VFD technology in wastewater treatment has not been given a trail before and enhances a proof of success will of tremendous positive impact when it comes to wastewater treatment (Burlage, 2012). It will offer not only alternatives but better and more reliable alternatives of treating wastewater.

Wastewater Collection

Wastewater collection: This is the first step of the treatment and involves the placement of collection systems by the concerned authorities to ascertain that the all the wastewater is collected and channeled to a central point after which it is directed to the treatment plant (Fang, 2010).

Odor control: Involves the elimination of the foul smell that comes with wastewater due to the presence of dirty chemicals. Odor in wastewater may result from the release of gases including hydrogen sulfide from the anaerobic processes that occur in the wastewater. The odor sources are managed and treated with the help of chemicals that are used in the neutralization of the elements that produce the smell. The level of hydrogen sulfide in the wastewater can effectively be managed by using such methods and devices as carbon regulators, calcium nitrate and hydrogen peroxide (Burton, 2013). By managing the levels of hydrogen sulfide, the concentration of the odors in the wastewater is reduced.

Screening: This is the first operation of treatment works in wastewater treatment. Screening removes the large non-biodegradable and floating solids which normally fins their way into a wastewater works including tins, plastics, wood, containers, papers and rags. When effectively remove these constituents aid in preventing any forms of physical damage to the plant and equipment that may result into unnecessary wear and tear as well as blockage of the pipes and accumulation of unwanted materials (Cecen, 2011). Such occurrences may lead to impairment of the wastewater treatment process. The process of screen in wastewater treatment can occur in two ways: course screening and fine screening. Course screens are mainly used as primary protection devices and in most cases have their openings to be larger than 10 mm.

Fine screens are mainly applied where there is need to remove objects that may lead to problems of maintenance and operation in the downstream processes especially in systems where primary treatment is missing. The opening sizes of fine screens are typically 3 to 10 mm and these values have been adjusted into the smaller opening sizes with the advancements in technology. Smaller sizes lower the sizes of suspended solid to almost those that are achieved with primary clarification (Burlage, 2012). A combination of both course and fine screening is applied in wastewater treatment process.

The screen chamber is designed in such a way that it meets the objectives of the screen process which is to eliminate large floating material and course solids from the wastewater. The screen chamber is made up of parallel wires, bars or grating that are positioned across the flow and inclined at 30?-60?. Screens are cleaned either manually using the hands or through mechanical processes. As a safety recommendation and provision, plants using mechanically cleaned screens have a standby screen that is usable in case of removal of the primary screen device (Frank, 2013).  

Odor Control

Primary treatment: This step involves separating macrobiotic solid matter from the wastewater and is achieved by pouring the wastewater in large tanks that allow the solid matter to settle on the surface of the tanks. Large scrappers are used in the removal of the solid waste that settles at the tanks’ surfaces. The solid matters are then pushed to the center of cylindrical tanks where they are later pumped off the tank for further treatment (Gerardi, 2015).

Secondary treatment: This step is also called the sludge activated process and encompasses the addition of seed sludge to the wastewater in a bid to have it broken down further. In this process, air is pumped into large aeration tanks that are used in the mixing of the wastewater and the seed sludge. Seed sludge is a small amount of sludge that used in igniting the growth of bacteria which use oxygen as well as the growth of other small microorganism that would be important in the consumption of the left organic matter. Secondary treatment results into the production of big particles which stele at the bottom of the large tanks. The wastewater is allowed to pass through the large tanks for a period of between 3-6 hours before it is allowed to leave (Groysman, 2016).

This step makes use of oxidation to facilitate further filtration of wastewater and is achievable through three different ways: biofiltration, aeration and oxidation ponds. Biofiltration deploys the use of sand filter, trickling filters or contacts filters to eliminate additional sediments from the wastewater. Trickling filters have been found to be the most effective filters for use with small-batch wastewater treatment. Aeration involves mixing the wastewater with microorganisms after which the resultant mixture is aerated for 30 hours at a time to achieve the desired results. Oxidation ponds are mostly applied in the warmer areas. This method as well makes use of natural water bodies like lagoons. In this method, wastewater is passed through the natural water body for some time before it is retained for two or three weeks (Burlage, 2012).

Bio-solids handling: This involves the direction of the solid matter collected in the primary and secondary treatment processes into digesters which are normally heated at room temperature. These solids wastes then undergo a one month treatment in which they undergo anaerobic digestion that results in the production of ammonia and bio-solids that are rich in nutrients. The methane gas produced in this process is used as a source of energy at the treatment plants but can as well be used in the production of electricity in engines or in the driving of plant equipment (Hofkin, 2010).

Screening

Tertiary treatment: This is an advanced treatment that comes immediately after secondary treatment and is geared towards improving the quality of the water. Tertiary treatment seeks to eliminate nutrients such as nitrogen and phosphorus from the water as well as all the suspended and organic matter. This process uses such substances as carbon and sand to assist in the removal of the named contaminants.  Numerous methods are deployed in the removal of these contaminants from the water (Gerardi, 2015).

The initial stage is filtration which mainly helps in the elimination or suspended waste matter from the wastewater. This stage is achieved using sand filtration method. In some cases, the wastewater may be contaminated with residual toxins which are removed sing activated carbon. Activated carbon achieves this by adsorbing the toxins and thus eliminating them from the wastewater.

There may be some fine particles of matter still remaining in the wastewater after filtration. The water is transferred to lagoons containing filter feeders such as Daphne. Inside the lagoon is an environment that is enriched both aerobically and biologically (Environment, 2012). Further elimination of fine particles of matter occurs in the lagoon. To this extent, the wastewater may still contain high concentration levels of nutrients such as phosphorus and nitrogen which if left untreated may be of significant harm to the natural environment through the creation of excessive growth and consequently the death and decomposition of algae. This then creates a need to reduce the concentration of the two nutrients in the wastewater before it is released into the environment (Hahn, 2012).

Nitrogen and phosphorus are removed from the environment using biological processes involving different bacteria. For the case of nitrogen, nitrogen in the form of ammonia undergoes oxidation to form nitrates which are then converted to nitrates and the nitrites and finally nitrogen gas which is released into the atmosphere (Aziz, 2015). Phosphorus is eliminated either biologically or through the use of chemical precipitation suing salts of aluminium, iron or even lime. Accumulating bacteria is used to accumulate the high content of phosphorus. Still, phosphorus can be removed in the form of sludge as a result of precipitation during chemical treatment.

Removal of undesirable microbes and odors from the wastewater is the last bit of tertiary treatment. The microbes are eliminated through disinfection. The clarity and the cloudy nature of the wastewater at this stage determine the efficiency and effectiveness of the process of disinfection adopted (Frank, 2013). Numerous agents of disinfection are used including chlorine, ozone as well as ultraviolet light with each of the agents bearing special features, advantages as well as disadvantages.

Primary Treatment

Disinfection: Involves the elimination of disease causing microorganisms that might still be present in the wastewater and is achieved by disinfecting the water for about 30 minutes in tanks containing mixtures of chlorine and sodium hypochlorite. This process helps in the safeguarding of the health of the people as well as the safety of the environment.

The main source of hydrogen sulfide in wastewater is the septic conditions during the collection and treatment of the wastewater. It has remained a major challenge that the municipal wastewater systems have remained to live with. It is produced through the biological reduction of sulfates and even decomposition of organic material and is formed at virtually every point in the treatment and collection system right from the interceptors through the force mains, lifts stations, holding tanks and drying beds (Judd, 2011). Other than the foul smell, the gas also acts a source of serious problems to the structural integrity of the collection system. A lot of money is lost as a result of corrosion that results from the interaction of hydrogen sulfide with moisture to form sulfuric acid. The greatest concerns are the safety hazards that come with the gas. Hydrogen sulfide gas is very toxic and has been established as a leading cause of death among those who work in the sanitary sewer systems. The gas causes fatigue, headache, eye irritation, sore throats among other health complications even at the lowest levels of concentration (Nemerow, 2010).

The occurrence of septic conditions is enhanced in warmer climates which have flat grade or otherwise have no flow-through velocities that is needed to prevent the stagnation of fluids. Septic conditions are achieved when all the available oxygen is used up by the bacteria in the process of decomposition of organic matter to release energy in the wastewater. Sewers that flow at relatively low velocities enhance the growth of anaerobic bacteria in the slime layer that coats the surface of sewer (Hofkin, 2010). These bacteria act to reduce compound containing sulphur such as sulfates to sulfides. Sulfides do not undergo oxidation under septic or anaerobic conditions. In this light, the sulfides combine with hydrogen to produce hydrogen sulfide gas that is responsible for the rotten egg smell that is associated with septic wastewater.

In cases where the concrete sewer is partly full, the surface that is damp and above the water line forms a habitat for the anaerobic bacteria which oxidize hydrogen sulfide to produce sulfuric acid. The acid formed attacks the constituents of cement that are made of calcium carbonate in the structure (Aziz, 2015). This results into the corrosion of the pipes of the collection system and the impact is quite severe at the crown of the pipe in which the collection of the acid occurs. This leads to an overall weakening of the pipe or the structure and hence enhances the potentiality of its collapse should the necessary measures not be put in place.

Secondary Treatment

The process of production of hydrogen sulfide is influenced by the temperature, pH as well as the concentration of the reactants. Hydrogen sulfide gas that is suspended in the sewer atmosphere can be adsorbed in the thin water film which usually covers the walls of the sewer (Programme, 2009). When this occurs, the hydrogen sulfide gas undergoes incomplete oxidation to form sulfuric acid with the help of bacteria that belongs to the Thiobacillus genus.

The presence of favorable loadings of nutrients and availability of plenty of space on top of the water line facilitates the formation of colonies of bacteria and the gas production in the wastewater environment (Cecen, 2011). The colonies of bacteria lower the pH of the system causing the Thiobacillus genus to oxidize hydrogen sulfide as well as yield sulfuric acid. The overall result of this process is corrosion normally referred to as Microbiologically Induced Corrosion which has a capability to quickly deteriorate iron piping and cement.

This challenge of corrosion is resolved by use of ventilation on the existing systems. The use of chemical treatment as well as applications of protective coatings has also proved efficient. Odors form the main challenge that come with the development of hydrogen sulfide in wastewater systems and is addressed through addition of chemicals such as compounds of chlorine (Spellman F. , 2016).

Production of hydrogen sulfide is a major issue when it comes to the corrosion of concrete and surfaces of metals. The pH of water is lower through the production of high amounts of sulfuric acid which tend to lower the pH of wastewater and hence leading to deterioration of concrete as well as corrosion of pipes.

Wastewater aeration is the processing of addition of air into the wastewater in order to facilitate bio-degradation of the components of the pollutants. This forms forma a fundamental aspect of the biological wastewater treatment systems and makes use of microorganisms that are naturally occurring in wastewater to degrade the contaminants of water (Abraham, 2014). Aeration is used as part of secondary treatment process which mostly adopts the activated sludge process. Aeration in the activated sludge process works by umping air into a tank that then enhances the growth of microorganisms in the wastewater. The microorganisms feed on the organic materials present which then form locks that can easily be settled out. Upon settling in a different tank, the bacteria that form the activated sludge flocks are constantly recirculated back to the aeration basis so as to enhance the process of decomposition.

Additional Filtration Techniques

Aeration works by providing oxygen to the bacteria which they use in the stabilization and the treatment of the wastewater (Wang, 2015). Oxygen is used by the bacteria in the degradation process in which the supplied oxygen is used by the bacteria to break down the organic matter in the wastewater into carbon dioxide and water.  A limited or no supply of oxygen, biodegradation of the incoming organic matter within a reasonable time becomes impossible. Degradation occurs under septic conditions that are usually very slow, odorous and yield pollutants that are not completely converted in the absence of oxygen. Some of the pollutants like hydrogen and sulphur are converted into hydrogen sulphide and carbon changed to methane under septic conditions in biological processes (Groysman, 2016). Other carbon particles are changed to carbonic acid which results into low conditions of pH in the basin making it even more challenging to treat the water.

Aeration brings into close contact water and air by exposing thin sheets of moisture to the air or by introducing small air bubbles and allowing them rise through the water. Dissolved gases are removed from the solution through the scrubbing process that is caused by the turbulence of aeration (Nielsen, 2016). This permits the escape of the gases into the surrounding air. Still, aeration is important in the removal of dissolved metals that are eliminated through oxidation. Upon oxidation, the chemicals fall out of the solution and become particles on their own in the water hence can be eliminated through filtration or floatation. The amount of surface contact between the water and the air determined the efficiency of aeration. This contact surface is a factor of the size of the air bubbles or water droplets. Oxygen added to the water in the aeration process has the capability of increasing the palpability of the water as it eliminates the flat taste. The temperature of the water determines the oxygen holding capacity of the water. Colder water holds more water than warm water (Sawyer, 2013).

• Volatile organic chemicals
• Ammonia
• Methane
• Hydrogen sulfide
• Chlorine
• Carbon dioxide
• Iron and manganese

Aerators are broadly classified into two: those that introduce water to the air and those that introduce air to the water. The air-in-water method establishes small air bubbles that are introduced into the water stream while the water-in-air method is designed to generate small drops of water that fall through the air (Fang, 2010). The design of the aerators is such that a greatest amount of contact between the water and air as possible to facilitate the transfer of gases as well as increase oxidation.

Bio-solids Handling

Cascade aerators: These are composed of a series of steps in which water flows over resembling a flowing stream (Fenchel, 2012). Aeration is done in the splash zones in cascade aerators which are formed by placing blocks across the incline. These aerators are used in oxidation of iron and partial reduction in dissolved gases.

 Cone aerators: These are mainly used for the oxidation of manganese and iron from ferrous state to ferric state just before filtration. They are designed in the same way as cascade aerators and have water being pumped to the tops of the cones before it is allowed to cascade down through the aerator.

Slat and Coke aerators: These are made up of stacked trays that are usually ranging three to five in number and have wooden spaced slats between them. The trays are filled with pieces of coke, ceramic balls, limestone or coke which are of the size of a fist. These materials are used in providing additional area of surface contact between the water and the air (Yi, 2009).

Draft aerators: In these aerators, the air is introduced using a blower. Two types of aerators are available: one having an external blower placed at the bottom of the tower to introduce air from the bottom of the tower and an induced-draft aerator. In the former type of draft aerator, water is pumped to the top of the tower and then allowed to trickle down through the rising air. For the case of an induced-draft aerator, there is a blower mounted at the bottom that forces air from the bottom vents up through the aerator to the top. Both types of draft aerators can effectively be used in the oxidation of manganese and iron before filtration (Speight, 2017).

Spray aerators have a spray or more spray nozzles which are connected to a pipe manifold. Water is ejected through the pipes under pressure and escapes through the nozzles in a fine spray which then falls into the surrounding air. Spray aerators are ideal for oxidization of manganese and iron as well as increasing the amount of dissolved oxygen in water (Veiga, 2013).

Pressure aerators: These exist in two main types: one using a pressure vessel and another pressure aerator. The pressure aerator that uses a pressure vessel has water being sprayed into air that has very high pressure which permits the water to pick up the dissolved oxygen quickly. The other which is a pressure aerator is used in pressure filtration in which air is introduced into the raw water piping and then permitted to stream into the water in the form of fine bubble which makes iron ready for oxidation (Burlage, 2012). A high pressure makes the amount of oxygen transferred to be higher thereby making more iron or manganese ready for oxidation.

Centrifugal aerators: These devices create conditions that enhance the dissolution of gases into liquid phase. Several elements are combined in this type of accelerator including:

• High turbulence swirling floe of liquid
• Minute pores which allow permeation of gas into liquid(Wang, 2015)
• Constant pressure inside the vessel
• Orthogonal flow of fluids
• Optimum velocity of flow that creates centrifugal forces

The Vortex Fluidic Device is a patented technology that illustrates the development a new space in chemical processing that allows strategies and tools with a range of research and industrial applications. This technology is a derivative of the major efforts in research that has concentrated on the applications of micro fluids in thin films such as film flow in chemistry. Such technology has enabled capabilities of harnessing high shear forces, reactions beyond control as well as micro mixing that have allowed exploration and enhancement of chemical reactivity from the views of batch processing and flow chemistry (Wang, 2015).

The Vortex Fluidic Device has the ability to instigate chemical reactivity, probe the structure of systems that are self-organized and material processing. Through this capability, the device achieves a variety of motifs that occur in a quick and controlled fashion. Vortex Fluidic Device is usable in the synthesis of urea, esters, alpha-amino phosphates, amides, modified amino acids, imines and beta-Keto ester besides local anesthetics called lidocaine. In comparison to the traditional batch processing (Nielsen, 2016). Vortex Fluidic Device highly enhances the rate of enhancements when carrying out these organic transformations. The assembly line process, which was a process developed in the illustration of a full floe system that occurs during total synthesis of lidocaine was a new paradigm development that was experienced in flow chemistry. The process permitted setting up of a molecular synthesis in a single rotating tube which has proved ideal in the creation of large libraries of compounds with the shortest time frames possible (Programme, 2009).

A significant number of processing capabilities are covered by the Vortex Fluidic Device technology ranging from small synthesis of molecules to advanced material processing and manipulation of single cell organisms (Ashton Acton, 2013). The basic principle of operation of the technology is its capability to manipulate or control various parameters which influence the dynamics of fluids and the shear forces that the fluids experience. Even though the technology lends itself to a mode of processing that is confined to small liquid volumes, it is designed from the outset wit capabilities of continuous flow processes. The volume of the material used in the processing determines the scalability of the processing. An example is the case where one Vortex Fluidic Device unit used in niche applications in nanotechnology and medicine or even a parallel collection of multiple units for greater volume industrial applications (Fang, 2010). 

The Vortex Fluidic Device is also ideal in the fabrication of mesoporous silica when it undergoes continuous flow at room temperature. This it achieved through variation in the shear rate while controlling the sizes of the pores. It is also applied in the folding of proteins under continuous flow, an important process in the pharmaceutical industry (Burton, 2013).

In summary, Vortex Fluidic Device operates under continuous flow by enhancing delivery of reagents to the lowest points of a rapidly rotating tube which is tilted in relation to the horizontal position (Nemerow, 2010). The inducible Faraday waves make an important tool while shear force is provided by the viscous drag from the layers of Ekman and Stewartson. The mechanoenergy released in the processed can be tapped and used in various processes and applications for example acceleration of organic reactions at room temperature. This it achieves without necessarily requiring heat like the case of conventional batch processing. Besides, high heat is generated from the intense micro-mixing which results into thin films (about 250 microns). The heat and mass transfer generated makes the molecules present in the system to undergo similar treatment. Processing through Vortex Fluidic Device goes beyond control diffusion and has high content of green chemistry metrics. It allows the study of reactions in real time through the use of a variety of modular attachments to evaluate the different parameters (Aziz, 2015). Still, Vortex Fluidic Devices enhance handling of harmful and exothermic reactions in flow through offering simplistic techniques that can be used in controlling the temperature released.

1. In a 5 liter beaker, add 4 litres of water
2. Add 20 g of sodium sulfide nonahydrate to the water
3. Add 100 g of clay
4. Establish the amount of organic matter(sodium sulfide nonahydrate) using a strip test
5. Refer to the scale on the strip tube
6. Add 30 g of sand, 50 ml of oil and wood debris(Khanal, 2011)
7. Place the beaker on a magnetic stirrer ensuring that the magnetized bar is at the bottom of the container.
8. To the mixture in the container, add 50 ml of yeast solution
9. Stir the mixture for one minute
10. Add soda ash or sodium hydroxide to the solution to adjust the pH as required (1,2, 3… 14)

Equipment

• A calibrated cylindrical container
• Stirring tool or equipment since the results will be used for quantitative analysis
• A digital time that has high accuracy in seconds(Khanal, 2011)
• Equipment for testing TSS
• A sample of the synthetic wastewater as prepared from the process above

To treat the synthetic wastewater using the conventional batch process, the tanks is filled with wastewater and then mixed with biomass which settles during the previous cycle. Air is then blown into the tank to facilitate biological growth as well as increase subsequent waste reduction. At this stage, mixing and aeration is stopped to permit settling of the solids to the bottom of the tank (Wang, 2015). Discharge of clarified effluents is done and sludge is removed at this step should there be need.

The sludge is allowed to settle and the position of the interphase of the liquid and the suspension is recorded at different intervals of time as illustrated in the diagram below. Taking records of the height of the interface between the suspension and the liquid at numerous intervals of time would result into a curve that has the evolution of the sludge blanket over the time interval covered. Standard measurements of the times for settling of the sludge are taken to be 0, 0.5, 1, 2, 3, 4, 5, 10, 15, 20, 25, and 30 and 45 minutes which can be varied depending on the variations in the settling of the sludge sample that is used for the experiment (Spellman F. , 2016). A measurement of the interfaces of the suspensions and the liquid is done more frequently at the beginning of the experiment since the interface moves rapidly. At later stages of the test, the frequency of measurement the interface is reduced since its motion is greatly reduced.

Protocol

• Ensure the synthetic wastewater sample is homogenous. Shaking the sample vigorously should be avoided as it would disturb the synthetic wastewater and thus alter the settling properties.
• Fill the cylindrical reservoir with the sample of synthetic wastewater. Pour the sample gently and in a manner that it flows continually so as to not disrupt the sludge too much nor permit it to settle again in the container(Yi, 2009).
• The time should be started immediately the column is filled with the synthetic sample of water.
• Takes measurements of the interface of the water and suspension at the time intervals 0, 0.5, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30 and 45 minutes(Nemerow, 2010)

Expectations

The settling curve plotted using the data from the experimental results will indicate different phases with each phase illustrating a change in the pattern or behavior of settling at the interface of the liquid and the suspension (Spellman, 2014). The settling behavior is different at each of the different depths of the suspension-liquid interface throughout the experiment. The depth of the interface decrease with an increase in the frequency of the time intervals. This means that the level of the suspension-liquid interface is highest at the beginning of the experiment when the time interval is zero and lowest at the end of the experiment, for this case at a time interval of 45 minutes from the beginning of the experiment

11. In a 5 liter beaker, add 4 litres of water
12. Add 20 g of sodium sulfide nonahydrate to the water(Speight, 2017)
13. Add 100 g of clay
14. Establish the amount of organic matter(sodium sulfide nonahydrate) using a strip test
15. Refer to the scale on the strip tube
16. Add 30 g of sand, 50 ml of oil and wood debris(Nielsen, 2016)
17. Place the beaker on a magnetic stirrer ensuring that the magnetized bar is at the bottom of the container.
18. To the mixture in the container, add 50 ml of yeast solution
19. Stir the mixture for one minute
20. Add soda ash or sodium hydroxide to the solution to adjust the pH as required (1,2, 3… 14)

Equipment

• A calibrated cylindrical container
• Stirring tool or equipment since the results will be used for quantitative analysis
• A digital time that has high accuracy in seconds(Wang, 2015)
• Equipment for testing TSS
• A sample of the synthetic wastewater as prepared from the process above

To treat the synthetic wastewater using the Vortex Fluidic Device, the tank is positioned in such a way that it is tilted in at an angle of 20? to the horizontal ground. Water mixed with biomass is then pumped into the tank from the bottom until it is completely full. The tank is then rotated at a very high speed ensuring that the angle of tilt is kept constant at 20? throughout the rotation cycle and the time is set to start counting on the time. Measurements are then taken on the levels of the different intervals of the suspension-liquid interface with time. Standard measurements of the times for settling of the sludge are taken to be 0, 0.5, 1, 2, 3, 4, 5, 10, 15, 20, 25, and 30 and 45 minutes which can be varied depending on the variations in the settling of the sludge sample that is used for the experiment (Aziz, 2015). After every time interval the setup is stopped before being restarted to proceed to taking readings of the subsequent time interval. In other words, the rotation of the cylinder is stopped after for example taking the measurement of the level of the suspension-liquid interface during the 5^th minute (Jansen, 2013). The solution is allowed to settle and then the experiment allowed moving to the next level. This ensures that highly levels of accuracy on the level of the interface at each of the time intervals as it aids in avoiding chances of superimposition of the readings from one interval onto another.

At the initial stages of the experiment, the measurement of the level of the suspension-liquid interface is frequently taken as there is rapid change in the level. As the cylindrical tank rotates, more and more of the wastes are eliminated at a relatively high rate hence resulting into rapid changes in the interface levels (Cecen, 2011). This calls for taking the measurements the level of the interface quite frequently during the initial stages of the experiment. During the last stages of the experiment on the other hand, are not accompanied by rapid change in the levels of the suspension-liquid interface levels hence the frequency of taking the measurements can be reduced.

• Ensure the synthetic wastewater sample is homogenous. Shaking the sample vigorously should be avoided as it would disturb the synthetic wastewater and thus alter the settling properties(Spellman F. , 2016).
• Fill the cylindrical reservoir with the sample of synthetic wastewater. Pour the sample gently and in a manner that it flows continually so as to not disrupt the sludge too much nor permit it to settle again in the container.
• The time should be started immediately the column is filled with the synthetic sample of water(Fenchel, 2012).
• Takes measurements of the interface of the water and suspension at the time intervals 0, 0.5, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30 and 45 minutes

The rate of elimination of wastes from the synthetic wastewater would be high at the beginning of the experiment. During such time a single rotation of the cylindrical tank would generate high amount of pollutants which would decrease as the experiment progresses. The least amount of wastes would be recorded at the last bit of the experiment which is at 45 minutes for the case of this set-up (Sawyer, 2013). This would be illustrated through the decrease in the depth of the interface with increase in time since the decrease is as a result of the wastes that have been eliminated.

References

Abraham, S. M. (2014). Measurement and Treatment of Nuisance Odors at Wastewater Treatment Plants. California: University of California, Los Angeles.

Ashton Acton, P. (2013). Sulfur Compounds—Advances in Research and Application: 2013 Edition. London: ScholarlyEditions.

Aziz, H. A. (2015). Control and Treatment of Landfill Leachate for Sanitary Waste Disposal. Sydney: IGI Global.

Burlage, R. (2012). Principles of Public Health Microbiology. New York: Jones & Bartlett Publishers.

Burton, F. L. (2013). Wastewater Engineering: Treatment and Resource Recovery. Washington DC: McGraw-Hill Education.

Cecen, F. (2011). Activated Carbon for Water and Wastewater Treatment: Integration of Adsorption and Biological Treatment. Toronto: John Wiley & Sons.

Environment, F. W. (2012). Design of Municipal Wastewater Treatment Plants MOP 8, Fifth Edition. Geneva: McGraw Hill Professional.

Fang, H. H. (2010). Environmental Anaerobic Technology: Applications and New Developments. Paris: World Scientific.

Federation, W. E. (2012). Design of Municipal Wastewater Treatment Plants MOP 8, Fifth Edition. Paris: McGraw Hill Professional.

Fenchel, T. (2012). Bacterial Biogeochemistry: The Ecophysiology of Mineral Cycling. Toronto: Academic Press.

Frank, S. (2013). Handbook of Water and Wastewater Treatment Plant Operations, Third Edition. New York: CRC Press.

Franklin, B. (2013). Wastewater Engineering: Treatment and Resource Recovery. New York: McGraw-Hill Education.

Gerardi, M. (2015). Wastewater Bioaugmentation and Biostimulation. London: DEStech Publications, Inc.

Groysman, A. (2016). Corrosion Problems and Solutions in Oil Refining and Petrochemical Industry. Manchester: Springer.

Hahn, H. H. (2012). Pretreatment in Chemical Water and Wastewater Treatment: Proceedings of the 3rd Gothenburg Symposium 1988, 1.–3. Juni 1988, Gothenburg. Oxford: Springer Science & Business Media.

Hofkin, B. (2010). Living in a Microbial World. London: Garland Science.

Jansen, J. L. (2013). Wastewater Treatment: Biological and Chemical Processes. Kansas: Springer Science & Business Media.

Judd, S. (2011). The MBR Book: Principles and Applications of Membrane Bioreactors for Water and Wastewater Treatment. Manchester: Elsevier.

Khanal, S. K. (2011). Anaerobic Biotechnology for Bioenergy Production: Principles and Applications. London: John Wiley & Sons.

Nemerow, N. L. (2010). Industrial Waste Treatment: Contemporary Practice and Vision for the Future. London: Elsevier.

Nielsen, P. H. (2016). Experimental Methods in Wastewater Treatment. London: IWA Publishing.

Programme, U. N. (2009). Global Atlas of Excreta, Wastewater Sludge, and Biosolids Management: Moving Forward the Sustainable and Welcome Uses of a Global Resource. Geneva: UN-HABITAT.

Sawyer, D. T. (2013). Industrial Environmental Chemistry: Waste Minimization in Industrial Processes and Remediation of Hazardous Waste. Washington DC: Springer Science & Business Media.

Speight, J. G. (2017). Handbook of Natural Gas Transmission and Processing. Paris: Elsevier.

Spellman, F. (2016). The Science of Wastewater. New York: DEStech Publications, Inc.

Spellman, F. R. (2014). Wastewater Stabilization Ponds. Chicago: CRC Press.

Veiga, M. (2013). Bioreactors for Waste Gas Treatment. Chicago: Springer Science & Business Media.

Wang, L. K. (2015). Fair, Geyer, and Okun's, Water and Wastewater Engineering: Hydraulics, Distribution and Treatment. Manchester: John Wiley & Sons.

Yi, Q. (2009). Point Sources of Pollution: Local Effects and their Control - Volume I. Sydney: EOLSS Publications.