The major constituent of living matter

The major constituent of living matter 2.0 LITERATURE REVIEW 2.1 Introduction Water is one of the major constituent of living matter. Around 50 to 90 percent of the weight of living organisms is water. The basic material of living cells, known as protoplasm, consists of a solution in water of fats, carbohydrates, proteins, salts and similar chemicals. Hence, water acts as a solvent which transports, combines, and chemically breaks down these substances. Water is also an essential element for the tourism industry. This is so, because the latter relies a lot on the agricultural industry for the provision of fresh fruits and vegetables for the Food and Beverages Department. Moreover, human beings are dependent on clean, pure and regular supply of water for drinking and other domestic purposes and in the tourism industry it is extensively used for recreation purposes such as in the swimming pools. Furthermore, water is used in the sewerage processing. Unfortunately, it is used indiscriminately for dumping wastes of all kinds and therefore, can be a major source of disease. Consequently, there can be a potential conflict of interest in the use of water resources. In addition, water is used for the generation of electricity which also forms part of the hospitality product. Electric energy is extensively used in each and every corner of hotels and is used in the heating and cooling systems. Also, machines and other equipment such as food processors, refrigerators and ovens need electricity to operate. However, the hospitality industry relies to a great extent on fresh and pure water to supply to its customers. Alongside, it should not be forgotten that this industry is at the same time generating loads of wastewater and since water follows a particular cycle, if somewhere along this cycle water is contaminated by pollutants; the supply of fresh water will be threatened. For this reason, it is of prime importance to preserve the water quality. 2.2 Water quality Water quality is the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. The desired quality of water must be related to the actual use of water supply. In terms of water quality, there are a number of chemical contaminants of water which are of great concern. These are lead, aluminium, nitrates and pesticides residues. It has been found that much of the lead present in domestic water supplies has arisen from the use of lead pipes. Lead is dissolved in water at a slow rate and thus it is the greatest concern in cases of slow-moving or stagnant water which has got an acidic pH. Lead also gets into the environment through the use of lead-based chemicals as a petrol additive. However, this source of lead is most significant as a contaminant of air. Aluminium, instead, enters water supplies either as a natural component of water which has passe d through acidic soils or as the compound aluminium sulphate which is used in the clarification of peaty water. It has also been suggested that aluminium and the disease known as Alzheimer are closely linked but this is still being disputed (Source: http://www.waterportfolio.com/).Nitrates in the water supply result mainly from the leaching of agricultural land. They are also present in discharges from sewerage plants. Moreover, some water supplies may contain chemicals which result in the hardness of the water. This hardness is usually caused by the calcium salts and magnesium salts found in the water. Normally, water found in kitchens, laundries, boilers and water-based heating systems do contain these salts and these minerals can be removed from the water by a simple process known as water filtration. This is imperative to be performed as drinkable water must be free from bacteria harmful to the health of human beings. The coliform bacteria are used as indicators of bacteriological water quality. These are associated with pathogenic organisms and are often indicators that a water supply has been contaminated with sewerage. If these bacteria are present in the water, there is a big possibility of faecal contamination and the presence of a number of micro-organisms which may cause gastro-intestinal infections in humans. These organisms might include species of Salmonella and Shigella, Vibrio chole ra, viral hepatitis A amongst others. They are destroyed by heat and chlorine-based disinfectants but can be a hazard in drinking water, water used in the kitchen and last but not least, ice. The most common methods of raw water treatment are firstly filtration to remove solids, taste and odour, secondly biological oxidation to remove organic matter including bacteria and lastly the removal; of iron, manganese, acids, odour and taste. Some substances such as non-biodegradable organic compounds, heavy metals, phosphates and ammonia are quite difficult and expensive to remove. However, chlorination is a common method for the disinfection of water supplies for domestic purposes and in swimming pools. Most of the water supplies must be treated before they are suitable for use in hotels. This treatment is normally carried out by a utility company, which is the Wastewater Management Authority. 2.3 Water and natural environment Water is the most precious gift of nature. It is the genesis of and continuing source of life. Without water, human kind and indeed all other forms of life on earth would not exist. Water is also essential for all development, be it social, industrial or agricultural. It is known to be an integral part of mans environment and the extent to which water is abundant or scarce, clean or polluted, beneficial or destructive determines the quality of human life. Hence, understanding the water cycle is one of the most important factors to be able to understand the environmental impact of wastewater if not well-treated. This is so because untreated wastewater causes loads of harm to the environment when discharged in nature. Water cycle is in fact the flow of water that is where water comes from and how and where it goes. The following diagram helps to better understand the entire water cycle process. The total supply of fresh water remains the same although man has been able to modify the patterns of availability of fresh water supplies with respect to time and space to a certain extent. It is the hydrological cycle which provides fresh water for meeting the various needs of people on the planet and which is relevant in consideration of water availability from year to year. The water cycle over the earth follows a path consisting of evaporation of water from the earths surface commonly from oceans, condensation of water vapour, cloud formation, precipitation and finally flow all over the land surface and even below it, to return back to the oceans lastly. But during the precipitation phase, the pure water supplies become contaminated with much undesirable materials like minerals leached from the soil. This is due to the use of excess nitrate-based fertilizers on land. The excess nitrates drain off into lakes, rivers and also to the underground water which finally goes into the se a. Although there are strict controls done upon the discharges into rivers and lakes, accidental pollution still occasionally occurs and this is why water needs to be treated before consumption and before it is released back to the environment. In hotels, water is more than just a utility. All hotels require considerable volumes of water, which is now becoming an increasingly scarce and expensive resource. Hospitality Operations take advantage of natural water features such as oceans and lakes. But the water quality which will be provided is very important. Water consumption and quality hence should be properly managed not only to keep an ecological balance but also for various reasons. This is because waste water diminishes a scarce resource and costs a lot of money to the hotels, hot water wastes waste not only water but also energy, poor quality water supplies can be risky to the health of both guests and employees and also it can increase the running and maintenance costs of equipment. Finally, contaminated wastewater increases the load on effluent plants and may endanger the water supply of others. 2.4 Water supplies in hotels Most hotels in Mauritius obtain their water from the utility company, Central Water Authority, CWA. Within the building, water supplies are designed to provide different types of water. This is so, because a variety of supplies are required (Lawson, 1976) in hotels for cold water for drinking, cold and hot water for bathrooms, cold water for toilets, hot water circulation for space heating, chilled water circulation for air conditioning, hot and cold water for kitchens and laundry, water for fire-fighting, water for swimming pools, fountains, artificial lakes and finally for watering green fields and ornamental plants. Many hotels offer extensive landscaping and sometimes added amenities such as golf courses. This aspect adds to the environmental impact of the hotels. For example, any golf course usually consumes a large quantity of water. Even a hotels normal landscaping will use large amounts of water and other chemical products. Therefore, to be ecologically sustainable, a hotels grounds and landscaping should run its operations in the â€Å"green way†. This means that the hotel should reduce the water demand, recycle and reduce solid wastes and also recycle and reuse materials as far as possible. As a matter of fact, water forms a major part of the products and services that hotels sell to their customers. This is why much importance should be given to its proper monitoring so that the customers satisfaction are reached or even exceeded and hence leading to the guests being happy. Besides, using water in the landscaping of the hotel will definitely give an aesthetic value to the hotels environment and thus when guests will step in the hotel, they will be charmed by its beauty and their holidays will start nicely. 2.5 Responsible institutions The Water Resources Unit (WRU), created in 1992, was operational as from 1993 and is responsible for the assessment, development, management and conservation of water resources in the Republic of Mauritius. The Unit is the nodal organization for the coordination of all activities concerning water resources management and has to communicate with all the major water user organizations. These are namely the Central Water Authority (CWA), Wastewater Management Authority (WMA), Irrigation Authority (IA) and finally the Central Electricity Board (CEB). WATER RESOURCES INSTITUTIONAL SET UP 2.5.1 Ministry of Public Utilities The Ministry of Public Utilities, MPU is responsible for Electricity and Power, including the Central Electricity Board; Water resources, including Central WATER Authority, Sewerage and other wastewater treatment and disposal including the Wastewater Management Authority and peaceful applications of ionizing radiations. The Ministry is the main body responsible for policy formulation and implementation as regards water resources. The main activity of this Ministry in Mauritius is that it formulates policies in the energy, water and waste water sectors and the establishment of a responsive legal framework to govern the development of these sectors. The Ministry also ensures that the necessary energy is created for services offered by the various organizations so that it will benefit the public. 2.5.2 Water Resources Unit The setting up of the Water Resources Unit was approved by the Government in April 1992. It was then a Division of the Ministry of Energy, Water Resources and Postal Services, which is now the MPU, with the responsibility for the development and the total management of the whole water resources of the country. The WRU started functioning from 07 May 1993, as a Division of the Ministry of Energy and Water Resources, presently MPU. The WRU is responsible for the assessment, development, management and conservation of water resources in the Republic of Mauritius.Some of the objectives of the WRU are to study and formulate policy in relation to the control and use of water resources for the provision of Water for domestic, agricultural, industrial and commercial supply and for hydro-electric power and for irrigation, land drainage and land reclamation, flood control, the development of fisheries, the protection of wild life, a forestation and the control of soil erosion, to investigate w ater resources and to collect, associate and interpret any data with regard to those resources, to prepare an inventory of water resources and to keep the inventory continuously up to date to update, on a regular basis, the Master Plan on the use of water resources, to ensure that appropriate measures are taken for the prevention of pollution of water resources, to prepare and follow up plans for the conservation, utilization, control and development of water resources, to prepare schemes for the development of river basins and trans-river basins, to conduct and co-ordinate research and investigation on the economic use of water, to promote, design and construct, with the help of appropriate authorities, schemes and works for the purpose of conservation and development of water resources, to inspect any work carried out in relation to water development or utilization purposes and to grant rights for the use of water and to issue permits, licences. 2.5.3 Central Water Authority The Central Water Authority established under the Central Water Authority Act of 1971 is responsible mainly for the treatment and distribution of potable water to domestic, industrial and commercial consumers while ensuring that the quality of treated water conforms to the World Health Organization (WHO) standards. Actually, around 99.6% of the population is connected to the piped water supply. 2.5.4 Wastewater Management Authority The Wastewater Management Authority constituted under the Wastewater Management Authority Act of 2000 is responsible for collection, transport, treatment and disposal of domestic and industrial including commercial sewage. In the year 1998 around 21% of the population was connected to the sewer system and the goal was to connect around 50% of the population by the year 2010. 2.6 Why treat wastewater Wastewater treatment is not a widely published fact, but there is no reason why it cannot be a widely acknowledged problem. The worlds supply of fresh water is slowly running dry. Forty percent of the worlds population is already dealing with the problem of water scarcity. Most of the diseases plaguing the world are water-borne. And while there is a child born every eight seconds in America, there is a life taken every eight seconds by some water-borne disease in other parts of the world. The fact is that there is a significant climate change, and as a consequence of this change, some regions are becoming drier while others are getting wetter. According to the United Nations, water scarcity is amongst the most serious crises facing the world and things are only getting worse. Uzbekistan and Kazakhstan of the erstwhile USSR, Chile, Mexico, Paraguay, Argentina, Peru and Brazil in Latin America, parts of China and the Middle East especially Iran, and more than 25 countries of Africa are all suffering from varying degrees of desertification. Global weather has gone awry. The problem of scarcity of water is making poor countries poorer. Countries that are already facing drought and famine are getting less and less water. Hence we have to become more water-efficient and get more from every gallon of water. And the only way to do this is to recycle and reuse waste water. Water is the giver of life and it has no substitute and therefore every drop of it counts a lot. Wastewater has to be treated so as to remove organic and inorganic matter which would otherwise cause pollution to the natural environment. Also it has to be treated so that all pathogenic organisms that are organisms which cause diseases can be removed in order to protect both the natural environment and human health. This should also be undertaken so as to reduce the impacts of both organic and inorganic matter on the marine environment. This is because wastewater constitutes of sediment which increases turbidity and blocks out sunlight into the sea, it reduces the rate of photosynthesis and hence can smother near-shore habitats. Moreover, wastewater contains oxygen demanding substances which if in high levels will result in a reduction in the amount of available dissolved oxygen. And finally, excess nutrients such as nitrogen and phosphorus are also present in wastewater which will cause excessive algal growth leading to oxygen depletion in the seas and hence eutrophication. Furth ermore, human exposure through direct and indirect contact to the pathogenic organisms in the sea may be fatal and even result into death. Some of the more common types of diseases associated with bathing in contaminated recreational waters or through consumption of contaminated sea food are swimmers itch, gastro-enteritis, dermatitis, viral hepatitis, wound infections, cholera, typhoid fever and dysentery. 2.7 Wastewater generated by hotels Hospitality facilities require large amounts of water and generate large amounts of waste as well. Water savings potentially vary greatly from hotels to hotels depending on types of facilities and how hotel guests use it. Water in hotels is used in guesthouse areas for bathing and sanitary purposes. Food and beverages operations and laundry operations have a great demand for water. They consume the maximum amount they can. An effective planning for large hotels should start with a grouping of functions for facilities to understand wisely how water is used and the water conservation potentials within each group. The purpose is to analyze all of these uses in an organized way. Usage of water within the hotel premise has got requirements regarding the quality of the water. Water quality refers to the bacteriological, physical, radiological and chemical characteristics of water relative to the safety for consumption. Standards specify maximum contaminant levels that may occur in portable water in the United States (US) are set forth in the safe drinking water Act 1974: It was amended in 1986 and again in 1996. The law is enforced by the US environmental Protection Agency. If the facility water comes from a source other than Public water utility, maintaining water quality becomes the responsibility of the hospitality manager. The HOTER project results in an 80% reduction in the water consumption of a classic hotel through the cost-effective treatment of its wastewater. This is achieved by means of a 2-stage covering treatment process that produces second class water that may be used for the flushing of toilet cisterns and landscaping and potable water that may safely be used as an alternative to conventional. The HOTER plant also results in zero-discharge to the environment and does require any chemicals or consumables. The mud resulting from the treatment plant can be used as a soil conditioner.A hotel using a HOTER plant can do away with a connection to the sewerage network, a huge benefit for hotels located in remote locations. In some hotels, a common way of treating water is to remove calcium or magnesium from the water. Removal of these minerals allows the water to more easily create a soap lather when bathing. It also reduces the chance of minerals buildup on plumbing fixtures and of spotting of surfaces. 2.7.1 Food preparation The following that can be taken to minimize the waste of water in this area: Staff should be well trained to defrost food by placing it in the fridge overnight, or in the microwave, rather than placing it under running water. Vegetable and fruits should be washed in a basin rather than under running tap water. Install flow controllers on taps. Use cold water rather than hot water wherever possible. Ensure that all the staff members are trained towards the conservation of water practices 2.7.2 Toilets Many hotels have their wastes carried by water and pressure through a piping system to a sewage treatment facility. Once the waste arrives at the sewage treatment facility it is contained in what are called reed beds where the waste undergoes a sanitation process which biodegrade rapidly by aid of exposure to elements such as rain and air. A reed bed used for sewage treatment is an eco-friendly process because very little energy for power is needed and a reed bed removes harmful pathogens within the waste before it can become an environmental or public health problem. Waste that has undergone the process of sewage treatment is easier and cost effective to dispose of and the treated wastes can be used for other things such as for agricultural purposes. The water which was used to carry the wastes to the sewage treatment facility along with rain water collections also undergoes a sanitation process then it is recycling for reuse. Conventional toilets use more water than is needed for their intended purpose. More and more hotels are installing eco-friendly toilets that use less water and can even recycle waste water for reuse to significantly reduce water and electricity usage to help conserve these two valuable commodities. Some are now also choosing composting toilets for recycling waste water and conserving electricity, and believe it or not the fact is that, properly composted human wastes can be used safely as agricultural and garden fertilizer. An eco-friendly composting toilet has two water holding tanks one which is known as Grey water and the other one as Black water. The grey water is the water used to flush wastes from the toilet bowl into the black water tank. There is a filtering system in which recycled waste water is sent to the grey water tank for reuse. The black tank holds liquid and solid wastes and also contains bacterial enzymes to aid in the breaking down or composting of wastes. When the black water tank becomes full it can be use as fertilizer for garden plants and flowers or it can be taken to a sewage treatment. In hotels, water used for flushing toilets and urinals can be up to 30%. 2.7.3 Grey water Grey watermay be defined as any household wastewater with the exception of wastewater from toilets, which is known as black water. It is important to point out that 50%-80% of household wastewater is grey water from kitchen sinks, dishwashers, bathroom sinks, tubs and showers. Freshly generated grey water is not as horrible as black-water, but if it is not handled properly it can soon become so. Grey water decomposes at a more rapidly rate than black water and if stored for as little as 24 hours, the bacteria in it use up all the oxygen and the grey water becomes anaerobic and turns infected. After this point it is more like black water stinky and a health exposure. In fact, many jurisdictions have strict regulations about disposal of grey water. It is not necessarily that all grey water is equally grey. Kitchen sink water laden with food solids and laundry water that has been used to wash diapers is more heavily infected than grey water from showers and bathroom sinks, even though grey water from these sources contains less pathogen than black water. It is possible to reduce 60% of the water used by recycling the grey water from baths and showers and rainwater. Research shows that economies can be made in hotels and guest houses by using grey water for toilets. But it has to be admitted that there will be extra costs for plumbing systems. 2.7.4 Baths and showers The need for eco-friendly bathrooms is on the rise. Water conservation products are becoming increasingly popular as consumers are going towards responsible water use. However, fashion aside, the planet has a crucial need for water conservation efforts. Every person can help to save water by making some changes in the place which uses the most water in every bathroom. Chemicals used in cleaning and body products also lead to polluted water, causing los of harm to the environment. There are approximately 1.4 billion cubic meters of water on Earth, 2.8 million cubic meters of which are available for use, an amount of only 0.1%. Water is a precious resource becoming scarcer each day. A single bathroom can use up to 100 litres of clean water daily. Contemporary water conservation efforts and eco-friendliness have begun focusing on making small changes in bathroom features and recycling grey water. Bathrooms use water for showers, toilets, and baths. On average, a shower uses almost 23 litres of water a minute, a toilet flushes with 8 litres of water and a bath uses almost 152 litres of water. Cutting down the amount of water used in a bathroom is not impossible. A bath uses two times more water than a shower, so having a short shower is the first step towards saving water. Keeping the shower to a maximum of five minutes is also efficient in saving a lot of water. Replacing a showerhead with a low flow fitting can help reduce water used by almost 16 liters. Also the tap should not be left running when using a wash basin for brushing teeth. This is also an important aspect to be respected. An eco-friendly bathroom should not only save on water, but should avoid all detrimental chemicals which are deadly to wildlife and eco-systems and aim to save energy. A geyser is often heated to far higher than necessary. Reducing the temperature setting on a geyser saves electricity, as does using a geyser blanket which keeps the geyser heated with less energy. There are a wide variety of cleaning products available which will clean a bathroom without spreading harmful toxins into the water and environment. To eliminate the need to use harsh chemicals is simple, by installing a fan above a bath or shower to remove excess moisture in a bathroom. Ceramic tiles for bathroom floors and to decorate the areas around the bath, shower and basin are eco-friendly, especially is made from recycled materials. Bamboo floors are also an eco-friendly alternative for bathroom flooring. A shower curtain made from fabric is far more environmentally friendly than plastic. A grated cover over the plughole of a shower, bath and washbasin will prevent materials from becoming clogged in drains and will thus cause blockages with extremely heavy corrosives which are harmful to the environment. It is the responsibility of every individual to help with the preservation of natural resources. A bathroom can be extremely taxing on the environment, and if each person instituted some eco-friendly practices into their bathroom, the world would save water, have less pollution and greater hope for the future. 2.7.5 Washing machines and Dishwashers There is considerable usage of washing machines if we consider the volume of laundry and washing-up generated by hotels. It should be noted that if less water is used in dishwashing then a greater amount of detergent and sanitizer needs to be used to achieve the same standard of hygiene hence the costs to the environment change remain the same. Hotel owners and managers benefit, because an efficiently running building requires fewer staff and results in lower operating expenses. Reduced costs can release valuable resources that can be better employed in improving or expending hotel facilities. Guests benefit because an efficiently controlled hotel satisfies the needs of the guests. Consequently this may result in a higher level of repeat business. Staff benefit through their empowerment, involvement and higher morale. This can lead to higher productivity, greater job satisfaction, lower levels of absenteeism and lower rates of staff turnover. The environment also benefits because a reduction in the use of water resources and decreased air, water and land pollution. By conserving all water supplies, there is a compatibility of economic interests and ecological requirements. Saving water charges, that is effluent charges resulting from the disposal of wastewater, saves the hotel money and conserves the water resources. Effective legal and regulatory protection of water, rivers, lakes and oceans is essential, so that it is compulsory for hotel companies to operate with standards that are higher than the often-minimal regulatory framework. Installing waste pipes for washing machines and dishwashers can be done simply by using long hoses and connecting them into the waste trap of your sink. This method is not advisable as it can take up a great deal of room in the under sink cupboards and the hoses usually need to be extra long which means they have a tenancy to sag and allow stale water to sit in them. Another problem is that the only way to connect a washing machine or dishwasher hose to a sink waste outlet is to use a jubilee clip onto a nozzle which is tapered. It is not believes that this is a good practice and sometimes washing machines and dishwashers wastewater is under quite a bit ofpressure when it is expelled by the machine. This could force the hose off. A washing machine or dishwasher waste is usually made with approximately 40mm plastic pipe. Therefore, it is always preferable to use solvent weld or compression fittings with the waste pipe because once it is made, it stays made and there is no chance of leaky joints. 2.8 Water and wastewater management in hotels Water is an efficient practice which is used to improve technologies that deliver both and equal and better services in using less water. The conservation of water also encourages hotels to manage how and when water is being used and by taking into great consideration both the technical and human aspects of water management issues. It has also been noted that in 2010 and 2011, that the use of water will increase to approximately 475 gallons per day for each luxurious hotels rooms. 2.8.1 Characteristics of wastewater There are two important characteristics of wastewater namely; Physical and Chemical. The physical characteristics consist of those items that can be detected with our physical sense. They are as follows: temperature, color, odor and solids. The chemical characteristics of wastewater of special concern to the Utilities man are pH, DO (dissolved oxygen), oxygen demand, nutrients, and toxic substances. 2.8.1.1 Physical characteristics Physical, aerobic, wastewater has been said to have the odour of kerosene or freshly turned earth. Aged, septic sewage is considerably more offensive to the olfactory nerves. The characteristic rotten egg odour of hydrogen sulphide and the mercaptans is indicative of septic sewage. Fresh sewage is typically grey in colour. Septic sewage is black. Wastewater temperature normally ranges between 10-20 °C. In general the temperature of wastewater will be higher than that of the water supply. This is because of the addition of warm water from the guestrooms, kitchens, laundry and heating within the plumbing systems of the structure or hotels. One cubic of wastewater weighs approximately 1,000,000 grams. It will contain about 500 grams of solids. One-half of the solid will be dissolved solids such as calcium, sodium, and soluble organic compounds.