Реферат: Hard Water Essay Research Paper Water is
Название: Hard Water Essay Research Paper Water is Раздел: Топики по английскому языку Тип: реферат |
Hard Water Essay, Research Paper Water is a tasteless odorless vital element in which 90 percent of all organisms depend on to survive. It is one of the best-known ionizing agents and, is frequently called the universal solvent . Water combines with certain salts to form hydrates. It reacts with metal oxides to form acids and it also acts as a catalyst in many important chemical reactions. Not only is it essential to our health, but it is also crucial in the household and the industrial world. Every day we use water for cooking, bathing, cleaning and drinking, but it s rare that we often think about how the minerals that can be found in it, could change the way we live our lives. The majority of the population seems very reluctant about the knowledge of where the water we use actually originated before it entered our faucets. When understanding the fundamentals of water and it s minerals, it is crucial to develop a better understanding of the whole process of water and how it is made accessible to us every day of our lives. According to the Water Quality Association, approximately 15percent of the Canadian population relies on individually owned and operated sources of drinking water, such as wells, cisterns and springs. On the other hand about 80percent of the population receives water from a community system (1). Household pumps and community water systems a generally used by the majority of consumers. Household pumps are designed to pump ground water for household use, while a community system may use surface water or ground water for its supply. There are two main sources of water: surface water and groundwater. Surface water can be found in lakes, rivers and reservoirs while ground water lies under the surface of the land. Consumers, who choose to have a private supply of ground water, are solely responsible for the safety of their water. The Water Quality Association states that even though private wells aren t subject to federal regulations, they are still regulated on a very limited basis in some provinces. Local health departments may also assist well owners with periodic testing for bacteria or nitrates (2). The Water association makes a point that, community water systems are required to meet the standards set by the Environmental protection Agency (EPA) under the authority of the Safe Drinking Water Act (SDWA) (3). Community water systems must ensure that the drinking water they supply does not have contaminant levels higher than standards of the SDWA amendments, or provincial regulations. The SDWA requires utilities to conduct routine monitoring and testing of public water supply. Two types of sampling are required. Routine sampling takes place on a regular basis and ensures that a treatment plant is running properly for delivering a consistent quality of drinking water. When a routine sample analysis indicates elevated levels of a particular contaminant that may exceed EPA or provincial standards, they may require systems to take a check sample. Check samples are used to confirm the results of a problem discovered during routine sampling. Whether consumers receive their water from a household well or a community system, they may wish t treat it at its point-of-use (POU). Even water supplied by a community water system, which meets EPA standards, can benefit from POU treatment. Consumers have the option to choose the higher quality of water that POU technologies can provide. Point-of-use technologies treat water at single or multiple taps or for the whole house, and can improve water quality in a variety of ways. One of the most popular POU technologies is water softening. Hard water is found throughout the world and in about 85% of Canada, according to the geological survey. Hard water areas exist where water has access to rock that contains calcium, magnesium, or a combination of both. According to the Water Council review, water is known to pick up some of everything that it touches, which is why it cleans so effectively. When it comes in contact with minerals, it creates hard water (4). Hard water is often not an obvious problem to people who have not had the opportunity to compare it to soft water. It is usually difficult to see or taste any difference between soft and hard water. The minerals that make water hard (Calcium and magnesium) are usually tasteless and completely dissolved. The differences between hard and soft water become more obvious in bathing and cleaning. According to Bill Andresen, of Saskatchewan Water, Hardiness is due to, the presence of multivalent metal ions which come from minerals dissolved in the water. Hardness is based on the ability of these ions to react with soap to form a precipitate or soap scum (5). In fresh water the primary ions are calcium and magnesium, however ion and magnesium may also contribute. Carbonate hardness is equal to alkalinity but non-carbonate fraction may include nitrates and chlorides. The Canadian council has established levels for classification of hardness based on (PPM). Natural resources and Environmental protection states that, the technique for analysis uses potentiometric titration on the computer aided titimeter (CAT) with copper ion-specific electrode. A reference substance, EDTA, is used as a titrant. Hardness is also expressed in mg/L of CaCO3 (even though all the hardness may not be due to CACO3) (5). Classification of Water hardness Content in (PPM) PPM Description 8-50 Very soft 50-120 Soft 120-600 Moderately hard 600-1200 Hard 1200-3000 Very hard Dealing with hard water can be a nuisance at home and throughout society. It may be hard to imagine that a small amount of calcium or magnesium dissolved in a gallon of water would have much of an effect, but the results can be far out of proportion to the actual concentration. Hard water has been proven to interfere with almost every cleaning task, from laundering and dishwashing to bathing and personal grooming. Clothes laundered in hard water may look dingy and feel harsh and scratchy. Dishes and glasses may be spotted when dry, and hard water also causes a film of a glass shower doors, shower walls, bathtubs, sinks, faucets etc. Everything from soap s ability to clean to life span of the washing machine can be effected. The waste hard water creates each year can cost hundreds of dollars in extra detergent use, unnecessary rinse cycles and hot water use, fabrics that lose their usefulness, and washing machines that wear out before their time. Hard water contributes to inefficient and costly operations of water using appliances. Heated hard water forms scales of calcium and magnesium minerals that can contribute to the inefficient operation or failure of water using appliances. Pipes can become clogged with scale that reduces water flow and ultimatley requires costly pipe replacement. A study conducted by the American Institute of Laundering determined that, detergent and laundering costs can be as much as twice as much in hard water as compared to soft water (6). Hard water is considered a nuisance, but most importantly it adds to a large amount of waste in our society. Laundry soap was the primary cleaning agent for laundry prior to the development of synthetic detergents. Soaps are usually natural, made from fatty acids and alkali substances such as caustic soda, which gives excellent cleaning properties, particularly with vegetable-based fabrics like cotton. Soap works well to suspend dirt in the was, and helps lubricate the fabric, prolonging it s life. Another advantage is that soaps are generally made up of 90 percent or more active cleaning agents, which reduces the amount required to use. Unfortunately, hardness minerals combine with soap to form an insoluble curd , which can remain as a residue on washed laundry. When doing laundry in hard water, soap curs get lodge in the fabric and create a stiff and rough surface on the clothes. Incomplete soil removal from laundry causes graying of white fabric and the loss of brightness in colors. A sour odor may develop in the clothes, and the continuos laundering can cause a shorter life span for the clothing. Hardness seems to counteract the soap’s alkalinity, which reduces its cleaning ability and requires the use of greater quantities to get the laundry clean. A partial solution to this problem, is the addition of builders such as complex phosphates, silicates, or sal-soda, which can be added to counteract the hardness. Builders boost the alkalinity of the wash, improving its cleaning ability. And also helping to neutralize acid soil and hardness caused by minerals. Bathing with soap in hard water leaves a sticky film of soap curd on the skin. The film may prevent removal of soil and bacteria, and the curd interferes with the return to the skins slightly acidic conditions. This soap curd has been known to cause skin irritations and can also leave the hair looking dull, lifeless and difficult to manage. Synthetic detergents introduces in the 1950 s were primarily designed to overcome hard water soap curd problem. Unlike unbuilt soaps, which are greater than 90 percent active, unbuilt detergents contain only 20 to40 percent active ingredients, and 50 to 65 percent neutral salts. The remaining ingredients are surfactants (which lower water s surface tension and improve its wetting ability). Suspension agents9which keep the dirt suspended, and whitening agents, which bring back the brightness. A Purdue university study found that, “fabrics washed in hard water tend to wear out as much as 15 percent faster than fabrics washed in soft water. This is due to the presence of hardness residues left in the fabric after laundering (7). The study also found that hard water has generally a negative effect on colors and whites. In addition, the study found that laundry washed in hard water became resoiled with greater ease. Not only does hard water have an effect on the household and industry, but also it has been proven that it also has a great effect on the environment. The most important impact of hardness on fish and other aquatic life appears to be the affect the presence of these ions has on the other more toxic metals such as lead, cadmium, chromium and zinc. Generally, the harder the water, the lower the toxicity of other metals to aquatic life. In hard water some of the metal ions form insoluble precipitates and drops out of solution and is not available to be taken in by the organism. Large amounts of hardness are undesirable mostly for economic or aesthetic reasons. If a scream or river is a drinking source, hardness can present problems in water treatment. Hardness must also be removed before industries can use the water. Water quality also has a great effect on herbicides and their effectiveness. According to Bill Andersen of Saskatchewan Water, Water cleanliness and its mineral content can affect the performance of some herbicides. Since, most herbicides used in Canada are mixed with water before the application. Particularly in products such as, diquat, paraquat, and glyphosphate (7). These products all demand clean, clear water for mixing as the herbicides effectiveness can be reduced by silt and organic matter. Calcium, magnesium and bicarbonate are minerals of concern for most farmers using these herbicides. Although there seems to be a great discussion about hardware and it s effects, there is much solution to treating hard water and making use of it in our society. The best solution to these hard water problems is to use soft water. This was realized by earlier generations that carried the phrase, hard water because it was hard to wash with it. Some utilities offer municipal softening, but water treatment in this manner falls short of being soft water. Municipal softening treatment is generally found in area of extreme hard water, and the end water is still often hard to moderately hard range. Municipal softening is often inefficient because all of the community s water is softened; including water used for watering lawns and clean public streets. Household water softeners generally provide the most economically effective source of soft water for the home and business use. A typical water softener works on the principal of cation exchange. In which the ions of the minerals are exchanged for sodium ions, effectively reducing the concentration of hardness to insignificant levels. After a period of use, the sodium or potassium ions are completely exchanged and the unit has to be backwashes or regenerated. This recharges the resin beads with sodium and potassium ions. This system requires the use of sodium or potassium chloride. Some concerns have been raised as to the presence of the sodium ions, especially as a result of the softening. The use of sodium ions does not make the water noticeable salty, nor does it significantly increase a person s sodium intake. As long as humans retrieve their water from an underground or surface source, we are going to constantly be overwhelmed by hard water problem in our society. We should not be concerned about hard water effecting our health, because intact, the National Research Council states that, drinking hard water generally contributes a small amount toward total calcium and magnesium in human dietary needs (8). It is our job as Canadians to build a better understanding toward our water supply and ways that we can keep it in a purified un- contaminated state, rather then complain about the effects that hard water has upon our lives. Scientists have gone to great lengths in order to find suitable ways of treating hard water for industrial and home use. Although hard water can be a nuisance to us, be should be grateful that whenever we turn on the tap, clean purified water lies waiting for us, unlike in many countries over the seas. We should stop being concerned about petty water problems and open up of views to the larger water problem of the world. |