High School English Essay Samples Secrets That No One Else Knows About

High School English Essay Samples Secrets That No One Else Knows About Life After High School English Essay Samples Writing a scholarship essay may not be a very simple endeavor for many students. We've got Professional Essay Writers online working 24x7 to offer you the very best assistance. Essay writing is normally practiced is schools. High school essay writing is a frequent classroom activity and is also part of several regular examinations. Students lead busy lives and frequently forget about a coming deadline. Actually, some teachers are so pressured to generate decent examination results that they're made to practise poor teaching procedures. Writing is not only for those that are studying nor for your teachers. From the outcome of the examinations, the teachers and planners of the curriculum will be in a position to assess the degree to which the students have acquired the wisdom and skills of the training course material. Whenever you opt to ask us for skilled guidance, don't hesitate to speak to our support managers. The not-so-positive facet of on-line education is that it might have a very long time to find feedback. A seasoned professional will make an error-free assignment very quickly and can help you boost your grades. Naturally, it's impossible for her or him to check all the assignments. Ruthless High School English Essay Samples Strategies Exploited It is possible to also get many discounts on ou r site which will help you to save some more money for future orders or anything you want to spend them on. You will be happy to know that it has best deals like gift vouchers etc. and should you shop above thousand then you'll get free delivery too. Shopping online isn't secure or secure. The Do's and Don'ts of High School English Essay Samples The web has made our life a good deal simpler. It is preferable to grow up in a family with plenty of brothers and sisters. Most folks obtain their very first love in high school. Some disasters are due to pilot error. What Everybody Dislikes About High School English Essay Samples and Why Writing an essay is a critical role in academe life. In this sort of essay, the writer is needed simply to explain the facts. It is a tough process in essay writing when you don't have a structure to follow. Your paragraphs do not connect one another's meaning in addition to the full thought of your essay may be incomprehensible. To compose an impressive short essay, especially during an examination, you must be in a position to hit the question and give a straightforward answer while at the identical time observing the proper structure of an essay. The simplest approach to influence the form of an essay is to realize the writer's point of view. You can acquire the ideal custom essay help from us in a variety of topics. Life, Death, and High School English Essay Samples Your college admissions essay is just one of the most crucial portions of your college application. Students Assignment Help isn't just offering English essay topic help for free but at the identical time assignments help in various subjects is also offered. It's evident that most students find it tricky to submit completely free error sample essay for financial need scholarship since mostly they give plagiarized content since they copy the precise information found on the web. Students have to compose essays based on the teacher's instructions or their preferred style in writing. Just open our English essay example and discover out what's written in an essay and the way that it is written. Like every assignment, a descriptive essay has a particular intent. The coming of the essay. How to compose an essay introduction. First and foremost it's imperative to make sure you comprehend the essay question fully and your essay answers each part of the question adequately. It's a review of the essay and thus you should not introduce any new points in the conclusion. Nobody really wishes to compose an essay. The essay may be one of the most daunting aspects of a university application.

Prepare Your Position Paper Topics on Climate Change

Prepare Your Position Paper Topics on Climate ChangePreparing a position paper is often a tough decision, particularly if you are in the field of environment or science. However, your work is only going to get harder if you attempt to write about climate change on an area of expertise, and where the subject matter is difficult to talk about, your ability to communicate will also become more difficult.Climate change is often difficult to discuss because it is perceived as something that is both dangerous and potentially catastrophic. The widespread feeling of the general public that something drastic will happen to the planet if there is no global warming is so strong that a lot of scientists feel that they can no longer write about the topic with any degree of clarity. Unfortunately, the general public is quick to be swayed by media headlines that have headlines that make it sound like man-made climate change is not real, and the vast majority of them will believe it.Climate change i s real and it is caused by humans, and the only question is how bad it will get. Scientists know this because they measure the natural changes to the earth's climate, and they see that it is altering due to human activity. When a new cycle of climate changes happens due to man-made emissions, this causes a certain amount of havoc, but it is nothing compared to what could happen if the whole world burns up.The topic of climate change is so controversial that there is a high demand for people who understand this topic. It is not unusual for one to have a waitlisted list of scientists and engineers who want to speak at conferences and workshops about how to deal with a crisis such as this. This demand means that you will find that people are lining up to write about the topic, regardless of the topic or expertise they have. However, if you are writing a paper about climate change, you should consider two important tips to help you along.First, you need to make sure that you make yourse lf appear as unbiased as possible when discussing a topic that you are unfamiliar with. You do not want to appear to be biased against a specific group or business that you may dislike because of their actions towards the climate, and especially the emissions and use of fossil fuels. By making sure that you stay neutral and unbiased, you will be able to make yourself appear to be a more convincing advocate for your cause.Secondly, you should make sure that you keep your writing simple. As easy as it may seem, it is not easy to convince readers about a complicated topic, and it takes more convincing to convince them that man-made emissions are the root of all evil. Writing a paper about a complex subject that is unfamiliar to you can be time consuming, and this will make your task more difficult. Take advantage of the fact that it is easier to write about a complicated topic in an orderly fashion than in an unsteady one.The more careful you are in your preparation, the better you wil l be able to make a successful paper. In addition, you will want to make sure that you have everything down before you go. You will want to be prepared and have your materials ready before you ever sit down to write. Being organized and knowing what you will say will help you get a greater sense of confidence in the job that you are doing.The decision to write about climate change can be made challenging because of the increased demand for paper topics. However, if you follow these simple tips, you will be able to provide a clear, succinct, and balanced report that will convince the reader that we are in the midst of a serious crisis related to the climate. A good report about climate change can help to educate the public about the issue, but it can also play a role in creating a storm over the issue by convincing those who are already skeptical of the need to take action.

Essay Topics About Dance and Music

Essay Topics About Dance and MusicMany students are interested in writing an essay about dance and music. Writing a paper with an overview of a subject is known as an overview or introduction. This will also be used to clarify what is covered in the entire essay.Begin with an essay topic that is interesting, not too difficult, and worth learning. Often, students select topics based on how they feel, such as if they are the only person in the class who has played the piano. Some people have even chosen topics based on past experiences, such as if they played jazz one day in high school, and they want to write an essay about it. Many times this approach to writing a paper is not what you would want to do with an overview.You may choose to write an essay on a popular song-writing topics, such as the Bible, classic literature, or philosophy. If you have an interest in dance and music, but it is just a hobby, you may choose to focus on dancing, how to play music, or even writing songs.Whe n choosing an essay topic for your own classes, be sure to narrow down the search by asking about the type of music you enjoy playing. If you are interested in jazz, classical, or some other form of music, you can go ahead and narrow down your search to specific topics. If you are interested in dance, you may choose general topics, or if you are into a particular style of dance, it may be difficult to narrow down the topic because you may not know what is out there.A great idea is to read through your favorite magazine, a book on writing, or visit some websites that have online forums about topics in the field. Many people find that reading a few articles online can give them a good idea about topics to include in their essay. They also can read books that cover specific topics in depth.dance and music essay topics It is important to remember that the more specific you are in your essay topic, the better it will be when you begin writing. There are many topics that cover much infor mation, and you may find that you have very little to say in your paper. If you spend too much time focusing on a limited topic, it will make it hard to add depth to the content when you write your paper.One important tip is to stay on topic. Stick to the main topic of your essay and don't stray off in another direction. Also, try to write an outline so that you don't end up with half of your essay written before you start the paper. Writing a paper can be tricky, but this can help you narrow down your selection of topics and helps you feel more confident about the topics you select.

Personal Statement Sample Essay Questions

Personal Statement Sample Essay QuestionsWhen writing your personal statement for the LSAT, one of the best types of essay questions to use is a Land Use Regulation Sample Essay Question. This type of question is designed to highlight a few of the fundamental and important points that you need to address in your personal statement. Writing this type of essay is a great way to create a concrete path for yourself as an undergraduate at the University of Texas.The first section of the Land Use Regulation sample essay questions is a comparison of Texas, Texas A&M, and UT Austin. This section is designed to highlight your credentials as an accountant who has worked in these three different companies. This is a good starting point for students who are applying to graduate school at the University of Texas.After making a comparison of these three schools, you will then have to choose between studying accounting at Texas A&M or accounting at UT Austin. You can further elaborate on th is choice by looking at the major among these three schools. The analysis provided by the Land Use Regulation sample essay questions should give you an idea of which of these schools you want to attend. At this point, you may wish to research your prospective school's admissions requirements.After selecting the school you wish to attend, you will then be presented with a list of essays to write. You will then have to consider all of the essay prompts that have been supplied to you. You should then spend some time reading through them and studying the structure and format. Using this information, you should then be able to formulate a well-structured essay that highlights your strengths, weaknesses, and exceptional abilities.The Land Use Regulation sample essay questions that you will receive are unique and are not offered during most applications. However, they are available if you have previously taken the LSAT or if you have already sent in an application to the University of Texa s. In order to make sure that your essay is as effective as possible, you should use this essay prompts.If you have not previously applied to graduate school at the University of Texas, you should consider sending in your application. The deadline for applying is usually two weeks after the start of classes for Fall semester. When applying to graduate school, you should prepare for the admissions process.If you are applying to graduate school in addition to the LSAT, you will also have to prepare for all of the essay prompts that are provided. Although most of the Land Use Regulation sample essay questions are similar to ones that you will receive for the LSAT, you should still read through them carefully.The Land Use Regulation sample essay questions should be considered when you are preparing to apply to graduate school. After all, this is the first essay that you will write for your application. Therefore, it is important that you utilize a sample essay as much as possible.

Solar Water Purifier free essay sample

BACKGROUND INFORMATION4 STATEMENT OF THE PROBLEM4 Objectives4 Justifications and significance4 Limitations4 Precautions5 Advantages5 CHAPTER 26 Literature review6 CHAPTER 37 Methodology7 Apparatus7 Procedure7 Observations7 CHAPTER 49 DATA ANALYSIS AND INTERPRETATION9 CHAPTER 510 CONCLUSION AND RECOMMENDATION10 REFERENCES10 CHAPTER 1: ABSTRACT BACKGROUND INFORMATION Solar water purifier is a device that purifies water through solar energy. Dirty water is a key link in the cycle of water borne diseases that affects the worlds’ poorest day who would otherwise contribute more to the overall economic and social development. Improved solar water purifier directly impacts on achieving universal education and reducing the rate of mortality. Water purification is the process of removing undesirable chemicals, biological contaminants, suspended solids and gases from contaminated water. The goal is to produce water fit for a specific purpose. Most water is purified for human consumption (drinking water), but water purification may also be designed for a variety of other purposes, including meeting the requirements of medical, pharmacological, chemical and industrial applications. We will write a custom essay sample on Solar Water Purifier or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page In general the methods used include physical processes such as filtration, sedimentation, and distillation, biological processes such as slow sand filters or biologically active carbon, chemical processes such as flocculation and chlorination and the use of electromagnetic radiation such as ultraviolet light. The purification process of water may reduce the concentration of particulate matter including suspended particles, parasites, bacteria, algae, viruses, fungi; and a range of dissolved and particulate material derived from the surfaces that water may have made contact with after falling as rain. The standards for drinking water quality are typically set by governments or by international standards. These standards will typically set minimum and maximum concentrations of contaminants for the use that is to be made of the water. It is not possible to tell whether water is of an appropriate quality by visual examination. Simple procedures such as boiling or the use of a household activated carbon filter are not sufficient for treating all the possible contaminants that may be present in water from an unknown source. Even natural spring water – considered safe for all practical purposes in the 19th century – must now be tested before determining what kind of treatment, if any, is needed. Chemical and microbiological analysis, while expensive, are the only way to obtain the information necessary for deciding on the appropriate method of purification. According to a 2007 World Health Organization (WHO) report, 1. 1 billion people lack access to an improved drinking water supply, 88 percent of the 4 billion annual cases of diarrheal disease are attributed to unsafe water and inadequate sanitation and hygiene, and 1. million people die from diarrheal diseases each year. The WHO estimates that 94 percent of these diarrheal cases are preventable through modifications to the environment, including access to safe water. [1] Simple techniques for treating water at home, such as chlorination, filters, and solar disinfection, and storing it in safe containers could save a huge number of lives each year. [2] Reducing deaths from waterborne diseases is a major public health goal in developing countries. STATEMENT OF THE PROBLEM The rate at which flooding occurs especially this season is rising at an alarming rate . Places such as Kano plains, Tana river , Budalangi are experiencing high levels of flooding. The water from floods may come across open sewerages, decaying organism and garbage which contaminate water sources. Such water is not healthy for human consumption. Approximately 1. 8 million people die due to diarrhoeal diseases such as cholera every year. Access to clean water is one of the global issues affecting the world and will continue to be so, as demand increases. Objectives 1 . Reduce intake and usage of dirty water domestically. 2. Reduce the number of medical cases brought about by intake of dirty water. 3. Introduction of a method of water purification which requires less human labour and its environment friendly. 4. To put an end to usage of chemicals in water purification which maybe a health hazard. Justifications and significance 1. It enables Kenyans to use clean water and minimize the medical cases brought about by dirty water. 2. It minimizes the rate at which people die due to water borne diseases. Limitations 1. It can’t work when the saturation deficit is low in the atmosphere. . It tends to be slow. 3. It is not portable. Precautions 1. It should be handled with care as it tends to be delicate. Advantages 1. It continues to work when sun rays are cut off because the black coating tends to lose heat at a lower intensity which can’t penetrate through the glass thus heat is retained. 2. Energy is readily available and renewable which is the sun. 3. The materials that are used to build it are locally available and at an affordable cost. 4. Its efficient and healthy as the water is purified at the end of the process. 5. Its environmental friendly as it doesn’t pollute the environment 6. It is ideal for the arid and semi –arid areas where there are high temperatures. CHAPTER 2 Literature review Sources of water Further information: Water supply 1. Groundwater: The water emerging from some deep ground water may have fallen as rain many tens, hundreds, or thousands of years ago. Soil and rock layers naturally filter the ground water to a high degree of clarity and often it does not require additional treatment other than adding chlorine or chloramines as secondary disinfectants. Such water may emerge as springs, artesian springs, or may be extracted from boreholes or wells. Deep ground water is generally of very high bacteriological quality (i. e. , pathogenic bacteria or the pathogenic protozoa are typically absent), but the water may be rich in dissolved solids, especially carbonates and sulfates of calcium and magnesium. Depending on the strata through which the water has flowed, other ions may also be present including chloride, and bicarbonate. There may be a requirement to reduce the iron or manganese content of this water to make it acceptable for drinking, cooking, and laundry use. Primary disinfection may also be required. Where groundwater recharge is practised (a process in which river water is injected into an aquifer to store the water in times of plenty so that it is available in times of drought), the groundwater may require additional treatment depending on applicable state and federal regulations. 2. Upland lakes and reservoirs: Typically located in the headwaters of river systems, upland reservoirs are usually sited above any human habitation and may be surrounded by a protective zone to restrict the opportunities for contamination. Bacteria and pathogen levels are usually low, but some bacteria, protozoa or algae will be present. Where uplands are forested or peaty, humic acids can colour the water. Many upland sources have low pH which require adjustment. 3. Rivers, canals and low land reservoirs: Low land surface waters will have a significant bacterial load and may also contain algae, suspended solids and a variety of dissolved constituents. 4. Atmospheric water generation is a new technology that can provide high quality drinking water by extracting water from the air by cooling the air and thus condensing water vapor. . Rainwater harvesting or fog collection which collects water from the atmosphere can be used especially in areas with significant dry seasons and in areas which experience fog even when there is little rain. 6. Desalination of seawater by distillation or reverse osmosis. 7. Surface Water: Freshwater bodies that are open to the atmosphere and are not designated as groundwater are classified i n the USA for regulatory and water purification purposes as surface water. Treatment The processes below are the ones commonly used in water purification plants. Some or most may not be used depending on the scale of the plant and quality of the raw (source) water. Pre-treatment 1. Pumping and containment – The majority of water must be pumped from its source or directed into pipes or holding tanks. To avoid adding contaminants to the water, this physical infrastructure must be made from appropriate materials and constructed so that accidental contamination does not occur. 2. Screening (see also screen filter) – The first step in purifying surface water is to remove large debris such as sticks, leaves, rubbish and other large particles which may interfere with subsequent purification steps. Most deep groundwater does not need screening before other purification steps. 3. Storage – Water from rivers may also be stored in backside reservoirs for periods between a few days and many months to allow natural biological purification to take place. This is especially important if treatment is by slow sand filters. Storage reservoirs also provide a buffer against short periods of drought or to allow water supply to be maintained during transitory pollution incidents in the source river. 4. Pre-chlorination – In many plants the incoming water was chlorinated to minimize the growth of fouling organisms on the pipe-work and tanks. Because of the potential adverse quality effects (see chlorine below), this has largely been discontinued. Widely varied techniques are available to remove the fine solids, micro-organisms and some dissolved inorganic and organic materials. The choice of method will depend on the quality of the water being treated, the cost of the treatment process and the quality standards expected of the processed water. H adjustment Pure water has a pH close to 7 (neither alkaline nor acidic). Sea water can have pH values that range from 7. 5 to 8. 4 (moderately alkaline). Fresh water can have widely ranging pH values depending on the geology of the drainage basin or aquifer and the influence of contaminant inputs (acid rain). If the water is acidic (lower than 7), lime, soda ash, or sodium hydroxide can be added to raise the pH during water purificati on processes. Lime addition increases the calcium ion concentration, thus raising the water hardness. For highly acidic waters, forced draft degasifiers can be an effective way to raise the pH, by stripping dissolved carbon dioxide from the water. Making the water alkaline helps coagulation and flocculation processes work effectively and also helps to minimize the risk of lead being dissolved from lead pipes and from lead solder in pipe fittings. Sufficient alkalinity also reduces the corrosiveness of water to iron pipes. Acid ( carbonic acid, hydrochloric acid or sulfuric acid) may be added to alkaline waters in some circumstances to lower the pH. Alkaline water (above pH 7. 0) does not necessarily mean that lead or copper from the plumbing system will not be dissolved into the water. The ability of water to precipitate calcium carbonate to protect metal surfaces and reduce the likelihood of toxic metals being dissolved in water is a function of pH, mineral content, temperature, alkalinity and calcium concentration. Coagulation and flocculation One of the first steps in a conventional water purification process is the addition of chemicals to assist in the removal of particles suspended in water. Particles can be inorganic such as clay and silt or organic such as algae, bacteria, viruses, protozoa and natural organic matter. Inorganic and organic particles contribute to the turbidity and colour of water. The addition of inorganic coagulants such as aluminum sulfate (or alum) or iron (III) salts such as iron(III) chloride cause several simultaneous chemical and physical interactions on and among the particles. Within seconds, negative charges on the particles are neutralized by inorganic coagulants. Also within seconds, metal hydroxide precipitates of the aluminum and iron (III) ions begin to form. These precipitates combine into larger particles under natural processes such as Brownian motion and through induced mixing which is sometimes referred to as flocculation. The term most often used for the amorphous metal hydroxides is â€Å"floc. † Large, amorphous aluminum and iron (III) hydroxides adsorb and enmesh particles in suspension and facilitate the removal of particles by subsequent processes of sedimentation and filtration. Aluminum hydroxides are formed within a fairly narrow range, typically: 5. 5 to about 7. 7. Iron (III) hydroxides can form over a larger pH range including pH levels lower than are effective for alum, typically: 5. 0 to 8. 5. In the literature, there is much debate and confusion over the usage of the terms coagulation and flocculation—where does coagulation end and flocculation begin? In water purification plants, there is usually a high energy, rapid mix unit process (detention time in seconds) where the coagulant chemicals are added followed by flocculation basins (detention times range from 15 to 45 minutes) where low energy inputs turn large paddles or other gentle mixing devices to enhance the formation of floc. In fact, coagulation and flocculation processes are ongoing once the metal salt coagulants are added. [10]:74-5 Organic polymers were developed in the 1960s as aids to coagulants and, in some cases, as replacements for the inorganic metal salt coagulants. Synthetic organic polymers are high molecular weight compounds that carry negative, positive or neutral charges. When organic polymers are added to water with particulates, the high molecular weight compounds adsorb onto particle surfaces and through antiparticle bridging coalesce with other particles to form floc. PolyDADMAC is a popular cationic (positively charged) organic polymer used in water purification plants. [9]:667-8 Sedimentation Waters exiting the flocculation basin may enter the sedimentation basin, also called a clarifier or settling basin. It is a large tank with low water velocities, allowing floc to settle to the bottom. The sedimentation basin is best located close to the flocculation basin so the transit between the two processes does not permit settlement or floc break up. Sedimentation basins may be rectangular, where water flows from end to end, or circular where flow is from the centre outward. Sedimentation basin outflow is typically over a weir so only a thin top layer of water—that furthest from the sludge—exits. In 1904, Allen Hazen showed that the efficiency of a sedimentation process was a function of the particle settling velocity, the flow through the tank and the surface area of tank. Sedimentation tanks are typically designed within a range of overflow rates of 0. 5 to 1. 0 gallons per minute per square foot (or 1. 25 to 2. 5 meters per hour). In general, sedimentation basin efficiency is not a function of detention time or depth of the basin. Although, basin depth must be sufficient so that water currents do not disturb the sludge and settled particle interactions are promoted. As particle concentrations in the settled water increase near the sludge surface on the bottom of the tank, settling velocities can increase due to collisions and agglomeration of particles. Typical detention times for sedimentation vary from 1. 5 to 4 hours and basin depths vary from 10 to 15 feet (3 to 4. 5 meters). [8]:9. 39-9. 40[9]:790-1[10]:140-2, 171 Inclined flat plates or tubes can be added to traditional sedimentation basins to improve particle removal performance. Inclined plates and tubes drastically increase the surface area available for particles to be removed in concert with Hazen’s original theory. The amount of ground surface area occupied by a sedimentation basin with inclined plates or tubes can be far smaller than a conventional sedimentation basin. Sludge storage and removal As particles settle to the bottom of a sedimentation basin, a layer of sludge is formed on the floor of the tank. This layer of sludge must be removed and treated. The amount of sludge that is generated is significant, often 3 to 5 percent of the total volume of water that is treated. The cost of treating and disposing of the sludge can be a significant part of the operating cost of a water treatment plant. The sedimentation tank may be equipped with mechanical cleaning devices that continually clean the bottom of the tank or the tank can be periodically taken out of service and cleaned manually. Floc blanket clarifiers A subcategory of sedimentation is the removal of particulates by entrapment in a layer of suspended floc as the water is forced upward. The major advantage of floc blanket clarifiers is that they occupy a smaller footprint than conventional sedimentation. Disadvantages are that particle removal efficiency can be highly variable depending on changes in influent water quality and influent water flow rate. [9]:835-6 Dissolved air flotation When particles to be removed do not settle out of solution easily, dissolved air flotation (DAF) is often used. Water supplies that are particularly vulnerable to unicellular algae blooms and supplies with low turbidity and high colour often employ DAF. After coagulation and flocculation processes, water flows to DAF tanks where air diffusers on the tank bottom create fine bubbles that attach to floc resulting in a floating mass of concentrated floc. The floating floc blanket is removed from the surface and clarified water is withdrawn from the bottom of the DAF tank. [8]:9. 46 Filtration After separating most floc, the water is filtered as the final step to remove remaining suspended particles and unsettled floc. Rapid sand filters Cutaway view of a typical rapid sand filter The most common type of filter is a rapid sand filter. Water moves vertically through sand which often has a layer of activated carbon or anthracite coal above the sand. The top layer removes organic compounds, which contribute to taste and odour. The space between sand particles is larger than the smallest suspended particles, so simple filtration is not enough. Most particles pass through surface layers but are trapped in pore spaces or adhere to sand particles. Effective filtration extends into the depth of the filter. This property of the filter is key to its operation: if the top layer of sand were to block all the particles, the filter would quickly clog. [11] To clean the filter, water is passed quickly upward through the filter, opposite the normal direction (called backflushing or backwashing) to remove embedded particles. Prior to this step, compressed air may be blown up through the bottom of the filter to break up the compacted filter media to aid the backwashing process; this is known as air scouring. This contaminated water can be disposed of, along with the sludge from the sedimentation basin, or it can be recycled by mixing with the raw water entering the plant although this is often considered poor practice since it re-introduces an elevated concentration of bacteria into the raw water Some water treatment plants employ pressure filters. These work on the same principle as rapid gravity filters, differing in that the filter medium is enclosed in a steel vessel and the water is forced through it under pressure. Advantages: †¢Filters out much smaller particles than paper and sand filters can. †¢Filters out virtually all particles larger than their specified pore sizes. †¢They are quite thin and so liquids flow through them fairly rapidly. †¢They are reasonably strong and so can withstand pressure differences across them of typically 2–5 atmospheres. †¢They can be cleaned (back flushed) and reused. Slow sand filters Slow artificial filtration (a variation of bank filtration) to the ground, Water purification plant Karany, Czech Republic Slow sand filters may be used where there is sufficient land and space, as the water must be passed very slowly through the filters. These filters rely on biological treatment processes for their action rather than physical filtration. The filters are carefully constructed using graded layers of sand, with the coarsest sand, along with some gravel, at the bottom and finest sand at the top. Drains at the base convey treated water away for disinfection. Filtration depends on the development of a thin biological layer, called the zoogleal layer or Schmutzdecke, on the surface of the filter. An effective slow sand filter may remain in service for many weeks or even months if the pre-treatment is well designed and produces water with a very low available nutrient level which physical methods of treatment rarely achieve. Very low nutrient levels allow water to be safely sent through distribution systems with very low disinfectant levels, thereby reducing consumer irritation over offensive levels of chlorine and chlorine by-products. Slow sand filters are not backwashed; they are maintained by having the top layer of sand scraped off when flow is eventually obstructed by biological growth. [citation needed] A specific large-scale form of slow sand filter is the process of bank filtration, in which natural sediments in a riverbank are used to provide a first stage of contaminant filtration. While typically not clean enough to be used directly for drinking water, the water gained from the associated extraction wells is much less problematic than river water taken directly from the major streams where bank filtration is often used. Membrane filtration Membrane filters are widely used for filtering both drinking water and sewage. For drinking water, membrane filters can remove virtually all particles larger than 0. 2 um—including giardia and cryptosporidium. Membrane filters are an effective form of tertiary treatment when it is desired to reuse the water for industry, for limited domestic purposes, or before discharging the water into a river that is used by towns further downstream. They are widely used in industry, particularly for beverage preparation (including bottled water). However no filtration can remove substances that re actually dissolved in the water such as phosphorus, nitrates and heavy metal ions. Removal of ions and other dissolved substances Ultrafiltration membranes use polymer membranes with chemically formed microscopic pores that can be used to filter out dissolved substances avoiding the use of coagulants. The type of membrane media determines how much pressure is needed to drive t he water through and what sizes of micro-organisms can be filtered out. Ion exchange:[12] Ion exchange systems use ion exchange resin- or zeolite-packed columns to replace unwanted ions. The most common case is water softening consisting of removal of Ca2+ and Mg2+ ions replacing them with benign (soap friendly) Na+ or K+ ions. Ion exchange resins are also used to remove toxic ions such as nitrate, nitrite, lead, mercury, arsenic and many others. Precipitative softening:[8]:13. 12-13. 58 Water rich in hardness (calcium and magnesium ions) is treated with lime (calcium oxide) and/or soda-ash (sodium carbonate) to precipitate calcium carbonate out of solution utilizing the common-ion effect. Electrodeionization:[12] Water is passed between a positive electrode and a negative electrode. Ion exchange membranes allow only positive ions to migrate from the treated water toward the negative electrode and only negative ions toward the positive electrode. High purity deionized water is produced with a little worse degree of purification in comparison with ion exchange treatment. Complete removal of ions from water is regarded as electrodialysis. The water is often pre-treated with a reverse osmosis unit to remove non-ionic organic contaminants. Disinfection Disinfection is accomplished both by filtering out harmful micro-organisms and also by adding disinfectant chemicals. Water is disinfected to kill any pathogens which pass through the filters and to provide a residual dose of disinfectant to kill or inactivate potentially harmful micro-organisms in the storage and distribution systems. Possible pathogens include viruses, bacteria, including Salmonella, Cholera, Campylobacter and Shigella, and protozoa, including Giardia lamblia and other cryptosporidia. Following the introduction of any chemical disinfecting agent, the water is usually held in temporary storage – often called a contact tank or clear well to allow the disinfecting action to complete. Chlorine disinfection Main article: Water chlorination The most common disinfection method involves some form of chlorine or its compounds such as chloramine or chlorine dioxide. Chlorine is a strong oxidant that rapidly kills many harmful micro-organisms. Because chlorine is a toxic gas, there is a danger of a release associated with its use. This problem is avoided by the use of sodium hypochlorite, which is a relatively inexpensive solution that releases free chlorine when dissolved in water. Chlorine solutions can be generated on site by electrolyzing common salt solutions. A solid form, calcium hypochlorite, releases chlorine on contact with water. Handling the solid, however, requires greater routine human contact through opening bags and pouring than the use of gas cylinders or bleach which are more easily automated. The generation of liquid sodium hypochlorite is both inexpensive and safer than the use of gas or solid chlorine. All forms of chlorine are widely used, despite their respective drawbacks. One drawback is that chlorine from any source reacts with natural organic compounds in the water to form potentially harmful chemical by-products. These by-products, trihalomethanes (THMs) and haloacetic acids (HAAs), are both carcinogenic in large quantities and are regulated by the United States Environmental Protection Agency (EPA) and the Drinking Water Inspectorate in the UK. The formation of THMs and haloacetic acids may be minimized by effective removal of as many organics from the water as possible prior to chlorine addition. Although chlorine is effective in killing bacteria, it has limited effectiveness against protozoa that form cysts in water (Giardia lamblia and Cryptosporidium, both of which are pathogenic). Chlorine dioxide disinfection Chlorine dioxide is a faster-acting disinfectant than elemental chlorine, however it is relatively rarely used, because in some circumstances it may create excessive amounts of chlorite, which is a by-product regulated to low allowable levels in the United States. Chlorine dioxide is supplied as an aqueous solution and added to water to avoid gas handling problems; chlorine dioxide gas accumulations may spontaneously detonate. Chloramine disinfection The use of chloramine is becoming more common as a disinfectant. Although chloramine is not as strong an oxidant, it does provide a longer-lasting residual than free chlorine and it wont form THMs or haloacetic acids. It is possible to convert chlorine to chloramine by adding ammonia to the water after addition of chlorine. The chlorine and ammonia react to form chloramine. Water distribution systems disinfected with chloramines may experience nitrification, as ammonia is a nutrient for bacterial growth, with nitrates being generated as a by-product. Ozone disinfection Ozone is an unstable molecule which readily gives up one atom of oxygen providing a powerful oxidizing agent which is toxic to most waterborne organisms. It is a very strong, broad spectrum disinfectant that is widely used in Europe. It is an effective method to inactivate harmful protozoa that form cysts. It also works well against almost all other pathogens. Ozone is made by passing oxygen through ultraviolet light or a cold electrical discharge. To use ozone as a disinfectant, it must be created on-site and added to the water by bubble contact. Some of the advantages of ozone include the production of fewer dangerous by-products and the absence of taste and odour problems (in comparison to chlorination) . Although fewer by-products are formed by ozonation, it has been discovered that ozone reacts with bromide ions in water to produces concentrations of the suspected carcinogen bromate. Bromide can be found in fresh water supplies in sufficient concentrations to produce (after ozonation) more than 10 ppb of bromate — the maximum contaminant level established by the USEPA. [13] Another advantage of ozone is that it leaves no residual disinfectant in the water. Ozone has been used in drinking water plants since 1906 where the first industrial ozonation plant was built in Nice, France. The U. S. Food and Drug Administration has accepted ozone as being safe; and it is applied as an anti-microbiological agent for the treatment, storage, and processing of foods. Ultraviolet disinfection Ultraviolet light (UV) is very effective at inactivating cysts, in low turbidity water. UV lights disinfection effectiveness decreases as turbidity increases, a result of the absorption, scattering, and shadowing caused by the suspended solids. The main disadvantage to the use of UV radiation is that, like ozone treatment, it leaves no residual disinfectant in the water; therefore, it is sometimes necessary to add a residual disinfectant after the primary disinfection process. This is often done through the addition of chloramines, discussed above as a primary disinfectant. When used in this manner, chloramines provide an effective residual disinfectant with very few of the negative aspects of chlorination. Various portable methods of disinfection Main article: Portable water purification Available for disinfection in emergencies or in remote locations. Disinfection is the primary goal, since aesthetic considerations such as taste, odor, appearance, and trace chemical contamination do not affect the short-term safety of drinking water. Solar water disinfection One low-cost method of disinfecting water that can often be implemented with locally available materials is solar disinfection (SODIS). [14][15][16][17] [18] Unlike methods that rely on firewood, it has low impact on the environment. One recent study has found that the wild Salmonella which would reproduce quickly during subsequent dark storage of solar-disinfected water could be controlled by the addition of just 10 parts per million of hydrogen peroxide. [19] Additional treatment options 1. Water fluoridation: in many areas fluoride is added to water with the goal of preventing tooth decay. Fluoride is usually added after the disinfection process. In the U. S. , fluoridation is usually accomplished by the addition of hexafluorosilicic acid, which decomposes in water, yielding fluoride ions. 2. Water conditioning: This is a method of reducing the effects of hard water. In water systems subject to heating hardness salts can be deposited as the decomposition of bicarbonate ions creates carbonate ions that precipitate out of solution. Water with high concentrations of hardness salts can be treated with soda ash (sodium carbonate) which precipitates out the excess salts, through the common-ion effect, producing calcium carbonate of very high purity. The precipitated calcium carbonate is traditionally sold to the manufacturers of toothpaste. Several other methods of industrial and residential water treatment are claimed (without general scientific cceptance) to include the use of magnetic and/or electrical fields reducing the effects of hard water. ] 3. Plumbosolvency reduction: In areas with naturally acidic waters of low conductivity (i. e. surface rainfall in upland mountains of igneous rocks), the water may be capable of dissolving lead from any lead pipes that it is carried in. The addition of small quantities of phosphate ion and increasing the pH slightly both assist in greatly reducing plumbo-solvency by creating insoluble lead salts on the inner surfaces of the pipes. 4. Radium Removal: Some groundwater sources contain radium, a radioactive chemical element. Typical sources include many groundwater sources north of the Illinois River in Illinois. Radium can be removed by ion exchange, or by water conditioning. The back flush or sludge that is produced is, however, a low-level radioactive waste. 5. Fluoride Removal: Although fluoride is added to water in many areas, some areas of the world have excessive levels of natural fluoride in the source water. Excessive levels can be toxic or cause undesirable cosmetic effects such as staining of teeth. Methods of reducing fluoride levels is through treatment with activated alumina and bone char filter media. Other water purification techniques Other popular methods for purifying water, especially for local private supplies are listed below. In some countries some of these methods are also used for large scale municipal supplies. Particularly important are distillation (de-salination of seawater) and reverse osmosis. 1. Boiling: Water is heated hot enough and long enough to inactivate or kill micro-organisms that normally live in water at room temperature. Near sea level, a vigorous rolling boil for at least one minute is sufficient. At high altitudes (greater than two kilometres or 5000 feet) three minutes is recommended. 23] In areas where the water is hard (that is, containing significant dissolved calcium salts), boiling decomposes the bicarbonate ions, resulting in partial precipitation as calcium carbonate. This is the fur that builds up on kettle elements, etc. , in hard water areas. With the exception of calcium, boiling does not remove solutes of higher boiling point than water a nd in fact increases their concentration (due to some water being lost as vapour). Boiling does not leave a residual disinfectant in the water. Therefore, water that is boiled and then stored for any length of time may acquire new pathogens. . Granular Activated Carbon filtering: a form of activated carbon with a high surface area, adsorbs many compounds including many toxic compounds. Water passing through activated carbon is commonly used in municipal regions with organic contamination, taste or odors. Many household water filters and fish tanks use activated carbon filters to further purify the water. Household filters for drinking water sometimes contain silver as metallic silver nanoparticle. If water is held in the carbon block for longer period, microorganisms can grow inside which results in fouling and contamination. Silver nanoparticles are excellent anti-bacterial material and they can decompose toxic halo-organic compounds such as pesticides into non-toxic organic products. [24] 3. Distillation involves boiling the water to produce water vapour. The vapour contacts a cool surface where it condenses as a liquid. Because the solutes are not normally vaporised, they remain in the boiling solution. Even distillation does not completely purify water, because of contaminants with similar boiling points and droplets of unvapourised liquid carried with the steam. However, 99. 9% pure water can be obtained by distillation. 4. Reverse osmosis: Mechanical pressure is applied to an impure solution to force pure water through a semi-permeable membrane. Reverse osmosis is theoretically the most thorough method of large scale water purification available, although perfect semi-permeable membranes are difficult to create. Unless membranes are well-maintained, algae and other life forms can colonize the membranes. 5. The use of iron in removing arsenic from water. See Arsenic contamination of groundwater. 6. Direct Contact Membrane Distillation (DCMD). Applicable to desalination. Heated seawater is passed along the surface of a hydrophobic polymer membrane. Evaporated water passes from the hot side through pores in the membrane into a stream of cold pure water on the other side. The difference in vapour pressure between the hot and cold side helps to push water molecules through. 7. Desalination is a process by which saline water (generally sea water) is converted to fresh water. The most common desalination processes are distillation and reverse osmosis. Desalination is currently expensive compared to most alternative sources of water, and only a very small fraction of total human use is satisfied by desalination. It is only economically practical for high-valued uses (such as household and industrial uses) in arid areas. 8. Gas hydrate crystals centrifuge method. If carbon dioxide or other low molecular weight gas is mixed with contaminated water at high pressure and low temperature, gas hydrate crystals will form exothermically. Separation of the crystalline hydrate may be performed by centrifuge or sedimentation and decanting. Water can be released from the hydrate crystals by heating[25] 9. In Situ Chemical Oxidation, a form of advanced oxidation processes and advanced oxidation technology is an environmental remediation technique used for soil and/or groundwater remediation to reduce the concentrations of targeted environmental contaminants to acceptable levels. ISCO is accomplished by injecting or otherwise introducing strong chemical oxidizers directly into the contaminated medium (soil or groundwater) to destroy chemical contaminants in place. It can be used to remediate a variety of organic compounds, including some that are resistant to natural degradation 10. Water Purification with Moringa Seeds Crushed Moringa seeds clarify and purify water to suit domestic use and lower the bacterial concentration in the water making it safe for drinking. Moringa seed powder can be used as a quick and simple method for cleaning dirty river water. Studies showed that this simple method of filtering not only diminishes water pollution, but also harmful bacteria. The moringa powder joins with the solids in the water and sinks to the bottom. This treatment also removes 90-99% of bacteria contained in water. [26] Demineralized water Distillation removes all minerals from water, and the membrane methods of reverse osmosis and nanofiltration remove most to all minerals. This results in demineralized water which is not considered ideal drinking water. The World Health Organization has investigated the health effects of demineralized water since 1980. [29] Experiments in humans found that demineralized water increased diuresis and the elimination of electrolytes, with decreased blood serum potassium concentration. Magnesium, calcium, and other minerals in water can help to protect against nutritional deficiency. Demineralized water may also increase the risk from toxic metals because it more readily leaches materials from piping like lead and cadmium, which is prevented by dissolved minerals such as calcium and magnesium. Low-mineral water has been implicated in specific cases of lead poisoning in infants, when lead from pipes leached at especially high rates into the water. Recommendations for magnesium have been put at a minimum of 10 mg/L with 20–30 mg/L optimum; for calcium a 20 mg/L minimum and a 40–80 mg/L optimum, and a total water hardness (adding magnesium and calcium) of 2 to 4 mmol/L. At water hardness above 5 mmol/L, higher incidence of gallstones, kidney stones, urinary stones, arthrosis, and arthropathies have been observed. [30] Additionally, desalination processes can increase the risk of bacterial contamination. [30] Manufacturers of home water distillers claim the opposite—that minerals in water are the cause of many diseases, and that most beneficial minerals come from food, not water. [31][32] They quote the American Medical Association as saying The bodys need for minerals is largely met through foods, not drinking water. The WHO report agrees that drinking water, with some rare exceptions, is not the major source of essential elements for humans and is not the major source of our calcium and magnesium intake, yet states that demineralized water is harmful anyway. Additional evidence comes from animal experiments and clinical observations in several countries. Animals given zinc or magnesium dosed in their drinking water had a significantly higher concentration of these elements in the serum than animals given the same elements in much higher amounts with food and provided with low-mineral water to drink. The solar water purifier ‘the best invention of the year’ enables users to drink water safely from contaminated water sources. It’s ideal for home owners during emergencies such as local flooding which can contaminate drinking water supplies. It is also ideal for campers and hikers who may be drinking from rivers or lakes; it is also ideal for travelers who don’t want to rely on the quality of local water. CHAPTER 3: Methodology Apparatus -Glass window. -Containers (3). -Charcoal. -Stands. Procedure Take a container A, pour dirty water and hang two pieces of cloth at its side ith their bases in contact with the water. The container should be raised 1metre above the ground. From the container A, a pipe should be leading to another container B containing charcoal. The whole part containing the tray with charcoal should have a black coating and be covered by a glass window . Lastly place container B at the end to collect the pure water. Observations The resulting water is clear. Water droplets were observed on the glass window. DATA It has been noticed there’s a high percentage of death due to dirty water . As stated earlier on, dirty water is a key link in the cycle of water borne diseases. 97 % of water in this world is salty sea water, 0. 07% retained water and 2. 23% is usable fresh water. The small percentage of water left is contaminated daily. The 97% of withheld water can be purified through the solar water purifier to solve strategies on lack of access of clean water. Approximately 1. 8 million people die due dirty water intake CHAPTER 4 DATA ANALYSIS AND INTERPRETATION 41% of 39. 8 million Kenyans do not have access to clean water. In 2008, only 59% of all Kenyans had access to safe water. 1 The 2006 drought in Kenya was declared a national disaster, as 3. 5 million people faced starvation and food shortages. 5 Droughts continue to plague the region. Beyond the threat of drought-induced food scarcity, 10% of deaths in Kenya occur from water-borne or sanitation-related diseases. 6 DATA SHOWING KEY STATISTICS IN THE WATER SECTOR IN KENYA PERCENTAGEDESCRIPTION 41%The number of people who do not have access to clean water 59%Have access to clean water 0%The percentage of land in Kenya that is arid and semi- arid 10%Percentage of deaths in Kenya caused by water and sanitation-related diseases SOURCES Ministry of water and sanitation http://www. quietway. org/water-for-kenya/ CHAPTER 5 CONCLUSION AND RECOMMENDATION As stated earlier, the solar water purifier is healthy and efficient as the end product is pure. The materials used to construct it are locally available and it requires less human labour to construct it. Besides it is environment friendly as it does not pollute the environment in any way. It is also advisable to use it in purification of tap water as it may contain lead due to metallic pipes. We would like to recommend that the solar water purifier should be used in places such as slums, arid areas, flooding areas, by campers and tourists who do not rely on local water. This will reduce the rate of medical cases linked with water borne diseases, not to forget the rising death rates. We recommend that the government should distribute the solar water purifier to the less privileged as that will aid them. REFERENCES F. A. ABOTT , ADVANCE LEVEL PHYSICS 1999, LONDON www. wikipedia. com www. deka. org/water purification