Properties and modern methods of purification of drinking water

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Background

• Safe drinking water is a human birthright – as much a birthright as clean air. However, much of the world’s population does not have access to safe drinking water. Of the 6 billion people on earth, more than one billion (one in six) lack access to safe drinking water.
• Moreover, about 2.5 billion (more than one in three) do not have access to adequate sanitation Services. Together, these shortcomings spawn waterborne diseases that kill on Average more than 6 million children each year (about 20,000 children a day). Water covers 70 percent of the globe’s surface, but most is saltwater.
• Freshwater covers only 3 percent of the earth’s surface and much of it lies frozen in the Antarctic and Greenland polar ice.
• Freshwater that is available for human consumption comes from rivers, lakes and underground sources and aquifers. Together these sources account for just 1 percent of all water on earth. Six billion people depend on this supply and a significant portion of the world’s population now face water shortages.

Techniques of water purification

Defluoridation

Defluoridation is the downward adjustment of the level of fluoride in drinking water. Worldwide, fluoride is one of the most abundant anions present in groundwater. Fluoride is more present in groundwater than surface water mainly due to the leaching of Minerals. Groundwater accounts for 98 percent of the earth’s potable water. An excess of fluoride in drinking water causes dental fluorosis and skeletal fluorosis. The World Health Organization has recommended a guideline value of 1.5 mg/L as the concentration above which dental fluorosis is likely. Fluorosis is endemic in more than 20 developed and developing nations.

Defluoridation of groundwater using brick powder as an adsorbent was studied in batch process. Different parameters of adsorption, viz. effect of pH, effect of dose and contact time were selected and optimized for the study. Feasible optimum conditions were applied to two groundwater samples of high fluoride concentration to study the suitability of adsorbent in field conditions. Comparison of adsorption by brick powder was made with adsorption by commercially available activated charcoal. In the optimum condition of pH and dose of adsorbents, the Percentage defluoridation from synthetic sample, increased from 29.8 to 54.4% for brick powder and from 47.6 to 80.4% for commercially available activated charcoal with increasing the contact time starting from 15 to 120 min. Fluoride removal was found to be 48.73 and 56.4% from groundwater samples having 3.14 and 1.21 mg l−1 fluoride, respectively, under the optimized conditions. Presence of other ions in samples did not significantly affect the deflouridation efficiency of brick powder. The optimum pH range for brick powder was found to be 6.0–8.0 and adsorption equilibrium was found to be 60 min. These conditions make it very suitable for use in drinking water treatment. Deflouridation capacity of brick powder can be explained on the basis of the chemical interaction of fluoride with the Metal oxides under suitable pH conditions. The adsorption process was found to follow first order rate mechanism as well as Freundlich isotherm.

Boiling

Boiling water is the cheapest and safest method of water purification. Water sources and or channels of distribution may render your water unsafe. For example, parasites and germs are things you may not see by bare eyes, but their effects can be life threatening.

In this method, clean water should be brought to boil and left at rolling-boil for 1-3 minutes. For people living in high altitude areas, it is recommended to boil your water for longer than water boiled at lower altitudes. This is because water boils at lower temperatures in higher altitudes. Boiled water should be covered and left to cool before drinking. For water drawn from wells, leave it for compounds to settle before you filter out clean water for use.

Filtration

Filtration is one of the effective ways of purifying water and when using the right multimedia filters it’s effective in ridding water of the compounds. This method uses chemical and physical processes to purify water and make it safe for human consumption. Filtration eliminates both large compounds and small, dangerous contaminants that cause diseases with a simple and quick filtration process.. Since filtration does not deplete all the mineral salts, water that has been filtered is considered healthier compared to water purified using other methods. It’s one of the effective water purification methods that utilize chemical absorption process that effectively removes unwanted compounds from water.

Compared to reverse osmosis, filtration is considered effective when it comes to selective elimination of much smaller molecular compounds such as chlorine and pesticides. The other factor that makes filtration less costly is that it does not require a lot of energy needed in distillation and reverse osmosis. It is an economic method of water purification because little water is lost during purification.

Distillation

Distillation is a water purification method that utilizes heat to collect pure water in the form of vapor. This method is effective by the scientific fact that water has a lower boiling point than other contaminants and disease-causing Elements found in water. Water is subjected to a heat source until it attains its boiling point. It is then left at the boiling point until it vaporizes. This vapor is directed into a condenser to cool. Upon cooling, vapor is reversed into liquid water that is clean and safe for drinking. Other substances that have a higher boiling point are left as sediments in the container.

This method is effective in removing bacteria, germs, salts and other heavy metals such as lead, mercury and arsenic. Distillation is ideal for people who have access to raw, untreated water. This method has both advantages and disadvantages. A notable disadvantage is that it is a slow process of water purification. In addition, it requires a heat source for the purification to work. Although cheap sources of energy are being developed, distillation remains a costly process of purifying water. It is only ideal (effective and least costly) when purifying small quantities of water (It is not ideal for large scale, commercial or industrial purification).

Chlorination

Chlorine is a powerful chemical that has been in use for many years to treat water for home consumption. Chlorine is an effective water purification method that kills germs, parasites and other disease-causing organisms found in ground or tap water. Water can be purified using chlorine tablets or liquid chlorine. As an off-the-shelf water purification product, chlorine is cheap and effective. However, caution should be taken when using chlorine liquid or tablets to treat drinking water. For example, people suffering from thyroid problems should talk to a medical practitioner before using this product. When using chlorine tablets, it is important to apply them in heated water, as they dissolve well in water that is at 21 degree Celsius or higher. Chlorine tablets kill all bacteria leaving your water clean and safe.

If you are looking for the best ways of treating your water, Schultz Soft Water is your best source of advice on best water purification methods and custom solutions to your water purification needs. Reverse osmosis is the best option, whereas filtering is good for basic water tasks such as sediment and chlorine removal. Reverse osmosis covers a larger spectrum of contaminant removal.

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Properties of Drinking Water

Drinking water is water that is safe and suitable for human consumption. It is typically treated to remove impurities and make it safe to drink. The properties of drinking water can vary depending on the source of the water and the treatment methods that are used.

Some of the important properties of drinking water include:

• Taste: Drinking water should have a pleasant taste. It should not be bitter, salty, or have any other unpleasant taste.
• Color: Drinking water should be clear and colorless. It should not have any visible particles or discoloration.
• Odor: Drinking water should have a faint, pleasant odor. It should not have any strong or unpleasant odors.
• Clarity: Drinking water should be clear and free of any visible particles.
• Hardness: Hardness is a measure of the dissolved minerals in water. Hard water can cause scale buildup in pipes and appliances.
• pH: The pH of water is a measure of its acidity or alkalinity. The pH of drinking water should be between 6.5 and 8.5.
• Total dissolved solids (TDS): TDS is a measure of the total amount of dissolved minerals in water. TDS can affect the taste and appearance of water.
• Microbiological quality: Drinking water should be free of harmful Microorganisms. These microorganisms can cause diseases such as cholera, typhoid, and dysentery.

Modern Methods of Purification of Drinking Water

There are many different methods that can be used to purify drinking water. Some of the most common methods include:

• Chlorination: Chlorination is the most common method of water purification. Chlorine is a disinfectant that kills harmful microorganisms in water.
• Ozonation: Ozonation is a newer method of water purification that uses ozone to kill harmful microorganisms. Ozone is more effective than chlorine at killing microorganisms, but it is also more expensive.
• Reverse osmosis: Reverse osmosis is a process that uses pressure to force water through a semipermeable membrane. The membrane removes most of the dissolved minerals and other contaminants from water.
• Ultrafiltration: Ultrafiltration is a process that uses a membrane with pores that are smaller than bacteria. The membrane removes bacteria and other microorganisms from water.
• Microfiltration: Microfiltration is a process that uses a membrane with pores that are larger than bacteria. The membrane removes larger particles, such as dirt and sediment, from water.
• Activated carbon filtration: Activated carbon filtration is a process that uses activated carbon to remove impurities from water. Activated carbon is a porous material that absorbs impurities, such as chlorine, pesticides, and herbicides.
• Distillation: Distillation is a process that uses heat to evaporate water. The water vapor is then condensed back into liquid form. This process removes most of the dissolved minerals and other contaminants from water.
• Ion exchange: Ion exchange is a process that uses resins to exchange ions in water. The resins remove harmful ions, such as lead and mercury, from water.
• Ultraviolet Light (UV) disinfection: UV disinfection is a process that uses ultraviolet light to kill harmful microorganisms in water. UV light is a powerful disinfectant that can kill bacteria, viruses, and parasites.

The best method for purifying drinking water depends on the source of the water and the contaminants that are present. It is important to consult with a water treatment professional to determine the best method for your needs.

Properties of drinking water

• Taste: Drinking water should have a pleasant taste that is not too salty, bitter, or metallic.
• Odor: Drinking water should have a faint, pleasant odor.
• Color: Drinking water should be clear and colorless.
• Turbidity: Drinking water should be free of suspended particles.
• Hardness: Drinking water hardness is caused by the presence of dissolved minerals, such as calcium and magnesium. Hard water can cause scale buildup in pipes and appliances, and it can also affect the taste of food.
• Chlorine: Chlorine is a common disinfectant that is used to kill bacteria in drinking water. Chlorine can have a strong odor, and it can also irritate the skin and eyes.
• Lead: Lead is a toxic metal that can cause serious health problems, especially in children. Lead can enter drinking water through the corrosion of lead pipes or solder.
• Mercury: Mercury is a toxic metal that can cause neurological problems. Mercury can enter drinking water through the release of mercury from industrial sources or from the burning of coal.
• Nitrates: Nitrates are a type of nitrogen compound that can be found in drinking water. Nitrates can cause health problems in infants, such as methemoglobinemia (Blue baby syndrome).
• Pesticides: Pesticides are chemicals that are used to kill pests, such as insects and rodents. Pesticides can enter drinking water through runoff from agricultural fields or from the use of pesticides in homes and businesses.
• Microbiological contaminants: Microbiological contaminants are bacteria, viruses, and parasites that can cause illness. Microbiological contaminants can enter drinking water through sewage contamination, runoff from agricultural fields, or from the use of untreated water in homes and businesses.

Modern methods of purification of drinking water

• Chlorination: Chlorination is the most common method of water purification. Chlorine is a disinfectant that kills bacteria and other microorganisms in water.
• Ozonation: Ozonation is a process that uses ozone to disinfect water. Ozone is a powerful oxidizing agent that kills bacteria and other microorganisms in water.
• Ultraviolet light: Ultraviolet light is a type of radiation that can be used to disinfect water. Ultraviolet light kills bacteria and other microorganisms in water by damaging their DNA.
• Filtration: Filtration is a process that removes suspended particles from water. Filtration can be used to remove sediment, bacteria, and other contaminants from water.
• Reverse osmosis: Reverse osmosis is a process that removes dissolved minerals and other contaminants from water. Reverse osmosis is a very effective method of water purification, but it can also remove beneficial minerals from water.
• Distillation: Distillation is a process that removes all contaminants from water by boiling the water and then condensing the steam. Distillation is a very effective method of water purification, but it can also remove beneficial minerals from water.

1. Which of the following is not a property of water?
   (A) It is a polar molecule.
   (B) It is a good solvent.
   (C) It is a good conductor of electricity.
   (D) It is a non-polar molecule.

2. Which of the following is not a modern method of purification of drinking water?
   (A) Distillation
   (B) Filtration
   (C) Osmosis
   (D) Boiling

3. Which of the following is the most common method of purification of drinking water?
   (A) Distillation
   (B) Filtration
   (C) Osmosis
   (D) Boiling

4. Which of the following is the most effective method of purification of drinking water?
   (A) Distillation
   (B) Filtration
   (C) Osmosis
   (D) Boiling

5. Which of the following is the least expensive method of purification of drinking water?
   (A) Distillation
   (B) Filtration
   (C) Osmosis
   (D) Boiling

6. Which of the following is the most energy-intensive method of purification of drinking water?
   (A) Distillation
   (B) Filtration
   (C) Osmosis
   (D) Boiling

7. Which of the following is the most environmentally friendly method of purification of drinking water?
   (A) Distillation
   (B) Filtration
   (C) Osmosis
   (D) Boiling

8. Which of the following is the most effective method of removing bacteria from drinking water?
   (A) Distillation
   (B) Filtration
   (C) Osmosis
   (D) Boiling

9. Which of the following is the most effective method of removing viruses from drinking water?
   (A) Distillation
   (B) Filtration
   (C) Osmosis
   (D) Boiling

10. Which of the following is the most effective method of removing parasites from drinking water?
    (A) Distillation
    (B) Filtration
    (C) Osmosis
    (D) Boiling