application of phytodisinfectants in water purification in akwa ibom state
APPLICATION OF PHYTODISINFECTANTS IN WATER PURIFICATION IN AKWA IBOM STATE
(A SEMINAR PAPER)
Water is essential for human survival. It has been reported that the total amount of water in the world is about 1400 million cubic km (= 1018 tonnes) and remains constant (ref. water cycle 207) Apparently, more than 97% of this total volume is seawater of the rest 22% is ground water and 97% is ice locked away in the glaciers and the polar ice cap. This obviously leaves less than 1% of the supply of fresh water, which takes in the water hydrological cycle, but half of this is found in rivers, lakes, and swamps. Most of the fresh water is polluted. In Northern Nigeria, for instance, 95% of the surface water, and this remains true for sub-Saharan Africa, is considerably polluted. This seminar paper discusses the concept of phyto-disinfectant of water purification. The process in water purification, types of phyto disinfectant, application of phyto disinfectant and importance of phyto disinfectant in water purification were discussed. Summary, recommendations and conclusion were put-forward.
Water is under increasing and competing demands from agricultural, industrial and domestic uses with increasing pollution threatening this scarce resource. The total volume of water as dictated by hydrological remains constant but contamination of water by geological, industrial and anthropogenic sources remains the greatest deterrent to Man’s usage. About 1.6 million people are forced to use contaminated water globally, (WHO, 1990). Uncontaminated water is rarely obtainable in rural Africa, Asia and especially in Subsaharan Africa where the prevalence of waterborne infectious diseases is sharply rising, (UNESCO, 2007).
Water borne diseases contribute to the death of about 4 million children in the developing countries per annum. As such, the world health organization has estimated that up to 80% of all disease and sickness in the world is caused by inadequate sanitation, polluted water or unavailability of water (Yongabi, 2009). The need to treat waste water both for domestic use and safe disposal to the environment is obviously exigent. In most developing nations, there are legislation/legal framework established to have industries and factories treat their wastewater before disposal but the cost has been prohibitive for most companies and as such very few companies treat their wastewater. Unlike in the Western countries, most companies treat their wastewater although at high cost, high energy inputs with complex and most often technologies that are not ecological (Gunnel, 2005).
Water management has become a global phenomenon. The beginning of the 21st century has experienced heightened awareness on ecological matters. Humankind has fully come to terms with the rapid urbanization and population growth that is invariably accompanied by adverse environmental problems. There are a number of natural, social and economic activities that affect water quality and availability (Prasad, 2009). There are some water bodies that are naturally defective due to the geology of the area. Besides, there are also natural and artificial water bodies like ponds that contain a lot of nutrients and unacceptable for consumption.
Natural disasters like the Tsunami in last December 2004 have generated a social quagmire and a scandal to the scientific world, as clean water and other embarrassing environmental challenges abound. Furthermore, conflict prone areas around Africa like the Dafur region of Sudan, DR Congo, to name a few, experience acute water crises. It has been estimated that 125 litres of water (potable) is required per person per day, yet, many households cannot actually boast of 25 litres of clean water per person per day. In tandem with this, water purification technologies would have to be reviewed in terms of its simplicity, accessibility (cost) and efficiency (Cofie and Keiaita, 2003). The search for simple, reliable and effective method of water treatment led to the use of plant materials including seeds of Moringa oleifera (WHO, 1990). Standard methods for the treatment of water include coagulation, flocculation, sedimentation and disinfection. These methods are often inappropriate due to prohibitive cost and low availability of chemical coagulants and disinfectants. Dosage and technique poses some local challenges, and for this reasons efforts to establish appropriate chlorination techniques for wells in rural communities is imperative (K.A Yongabi (2004).
Regrettably, the available technologies in present day do appear complex and still expensive. No doubt, despite tremendous awareness campaign during the water and sanitation decade of 1981-1990, water and sanitation problems today still remain a major task to reckon with. If the Millennium Development Goals in the water and sanitation sector are something to go by, then the need to focus on integrated low cost water purification systems at grassroots stands unequivocal.
In Nigeria, 80-90% of all infectious diseases are water borne. Governments in these countries spend a significant proportion of their budgets importing alum and chlorine from western nations for municipal water treatment. More than 1.2 million people lack safe drinking water in developing countries. Apart from high cost of treating water in sub-Saharan Africa, waterborne microorganisms are developing resistance to currently used disinfectants such as chlorine. To meet the United Nations Millennium Development Goals (MDG) of providing safe drinking water, alternative and complimentary approaches such as the application of Moringa oleifera plant materials and sand filters are being studied. Previous research regarding the application of Moringa oleifera (MO) seeds have focused on the isolation of bioactive coagulant ingredients for more than four decades, with little attention directed toward field application in small and large scale water treatment applications. Slow sand filters take more than two weeks to generate clean water but there have been few studies directed towards integrating Moringa oleifera and other plant disinfectants with sand filters to generate clean water in a relatively short retention times at faster flow rates.
application of phytodisinfectants in water purification in akwa ibom state
1.1 Background of the Study
Safe drinking water and adequate sanitation are essential for human health and dignity. However, 1.2 billion people do not have (Pritchard et al., 2009; UNICEF, 2009). Approximately, 2.5 billion people in the world lack adequate sanitation facilities (UNICEF, 1993; UNEP 2002; Zhang et al., 2006; UNESCO, 2007; UNICEF, 2009). Waterborne and water related diseases such as diarrhea, typhoid, cholera and drancunculiasis are fast becoming endemic in certain parts of Africa (Cheesbrough, 1984; Yongabi, 2004; Pritchard et al., 2009). Yet, the present well documented technologies used in water treatment such as reverse osmosis, ion exchange, uv sterilization, aluminum sulphate and chlorine are becoming unsustainable, unecological, expensive to run, managed and maintained, particularly in Africa (Pritchard et al., 2009). For example, Chlorine is known to produce trichloromethane, a cancer precursor (Yongabi, 2004) while Aluminum sulphate has been linked to Alzheimer’s disease (Zhang et al., 2009). Furthermore, the cost of purchasing synthetic coagulants and disinfectants is in hard currency leading to high pricing for treated water in Africa (Kebreab et al., 2005). Simple technologies such as the application of plant coagulants such as Moringa oliefera to treat water has been extensively reported (Oliver, 1959; Jahn, 1981; Muyibi et al., 2002; Yongabi, 2004; Pritchard et al., 2009).
Interest in isolating and purifying bioactive Moringa oleifera coagulant ingredient has grown and outweighed efforts on taking inventory of other potential plant coagulants and disinfectants. The most important step in water treatment is disinfection. Attention has been focused on screening plants for coagulant activity (Eilert, 1978; Jahn, 1981; Muyibi et al., 2002a; Kebreab et al., 2005; Amir et al., 2010), but not all coagulants are disinfectant. The flora of Africa is rich with a lot of medicinal plants and Macro fungi which people in the rural areas are quite familiar. Sofowora (1982) and Yongabi (2004) reported that Africa has as much as 300, 00 medicinal plants while Chang (1993) reported that the world mushroom biodiversity is as much as 1.5 million species. There is, therefore, an urgent need to explore and utilize these rich biodiversity through researches that could translate to direct benefit to humankind (Yongabi, 2009). Plant disinfectants could provide useful insight for the production of natural disinfectants and coagulants which are environment friendly and with much reduced risk of handling. The ultimate purpose of this seminar is to carry out an inventory of plants used as disinfectants in Uyo – the capital of Akwa Ibom State, Nigeria, conduct an in vitro evaluation of crude plant powders and solvent extracts on directly disinfecting turbid surface water from the area.
1.2 Definition of Terms
(i) Phyto: Phyto means plant. Word-forming element meaning “plant,” from Greek phyton “plant,” literally “that which has grown,” from phyein “to grow”. In the direct in-situ removal of pollutants, (hyper) accumulating crops are cultivated. The crops are cut and transported for composting or controlled incineration. In farming areas, the intention is for these activities to be carried out by the farmers themselves.
The plant-types that are suited to this technique are those that have a high in-take capacity. In addition to this, it is important that the crops have a high return of (mowable) dry matter. If the crop has another economic and/or agricultural value, this is definitely a plus point.
Grasses and clover appear to be ideal for phyto-remediation because they have a fibrous root system which forms a permanently-compact rhizosphere (the soil in the immediate surrounding of the plant roots). This also provides the additional benefit that soil is protected against water and wind erosion. Literature makes reference to the following grasses: Alfalfa, clover, fescue grass, Bermuda grass and rye-grass.
Plants can also be transformed to selectively extract and accumulate heavy metals, so that potential metal-rich residues can be recycled. Transgenic tobacco and potato are good examples. By way of this transformation, the tolerance to heavy metals is also increased.
(ii) Disinfectant: Disinfectants are antimicrobial agents that are applied to the surface of non-living objects to destroy microorganisms that are living on the objects. Disinfection does not necessarily kill all microorganisms, especially resistant bacterial spores; it is less effective than sterilization, which is an extreme physical and/or chemical process that kills all types of life. Disinfectants are different from other antimicrobial agents such as antibiotics, which destroy microorganisms within the body, and antiseptics, which destroy microorganisms on living tissue. Disinfectants are also different from biocides — the latter are intended to destroy all forms of life, not just microorganisms. Disinfectants work by destroying the cell wall of microbes or interfering with their metabolism.
In wastewater treatment, a disinfection step with chlorine, ultra-violet (UV) radiation or ozonation can be included as tertiary treatment to remove pathogens from wastewater, for example if it is to be reused to irrigate golf courses. An alternative term used in the sanitation sector for disinfection of waste streams, sewage sludge or fecal sludge is sanitisation or sanitization.
Therefore, disinfection does not necessarily kill all microorganisms, especially resistant bacterial spores; it is less effective than sterilization, which is an extreme physical and/or chemical process that kills all types of life. Disinfectants work by destroying the cell wall of microbes or interfering with their metabolism.
(iii) Purification: Purification is the removal of impure elements from something. After purification, water is safe to drink. Most cities have a system of water purification, so people get clean fresh drinking water without any parasites or goldfish in it.
Purification is when things are cleaned and made pure. Salt water must undergo purification before it’s safe to drink. Some filters do a purification of the air to reduce allergens Water purification, process by which undesired chemical compounds, organic and inorganic materials, and biological contaminants are removed from water. The purification procedure reduces the concentration of contaminants such as suspended particles, parasites, bacteria, algae, viruses, and fungi.
Phyto Disinfectant: Phytodisinfectants are plant materials used in treating turbid water and can be applied in wastewater treatment.
Water: Water in its natural state is a liquid; it is ever changing, when heated it becomes steam (vapor) and when cooled it becomes ice (a solid). Water covers over 70% of the Earth’s surface and is vital for the existence of all forms of life, yet less than 3% of water is in its consumable form and 98% of that is either ice or underground. About 96% of the planet’s water is in the salty seas and oceans. Water is important to life, industry, food, recreation, and energy. It is considered the universal solvent. There is no man-made or natural obstacle that water cannot overcome through time, erosion, pressure, or change of state.
- Literature Review
2.1 Concept of Phytodisinfectant in Water Purification
Despite the technological advancement in water treatment and supply, one major challenge facing many developing countries today is lack of clean and safe drinking water to its citizens. It has been estimated that, 1.2 billion people do not have clean and safe drinking water (Pritchard et al., 2009). In Nigeria for instance, some municipalities are spending around 50% of their annual recurrent cost on water supply (Muyibi and Okufu 1995). In third world countries, many communities depend to a large extent on pond and other surface water sources for their domestic water supply. This could be an open borrow pit left during/after road construction or a river. River water drawn for consumption or general household use is highly turbid, especially in the rainy season. Studies have shown that, one major problem with the treatment of surface water is the large seasonal variation in turbidity (McConnachie et al., 1999). Turbidity in water is caused by suspended matter such as clay, silt, finely divided organic and inorganic matter, planktons, and other microscopic organisms (American Public Health Association/American Water Works Association 1989, Nwaiwu and Lingmu 2011).
Turbidity can provide food and shelter for pathogens and if not removed can provide a condition for re-growth of pathogens in the distribution system (Nwaiwu and Lingmu 2011). The consumption of high turbid water may lead to water borne disease outbreak. Water and water related diseases such as diarrhea, typhoid, cholera, and drancunculiasis are fast becoming endemic in certain parts of Africa (Yongabi, 2004; Prichard et al., 2009). To control these diseases, water needs to be purified in order to make it safe for human consumption. However, for many developing countries, coagulation, flocculation and sedimentation are expensive processes of water treatment because of high cost involved to import chemicals in hard currency, leading to high pricing for treated water and the difficulties in accessing the chemicals (Ghebremichael, 2004; Kebreab et al., 2005). Chemical disinfectants like chlorine are not only expensive but have general health effects and environmental problems. Its usage generally resulted in production of trihalomethane, a cancer precursor (Yongabi, 2004) while alum is linked to Alzheimer disease (Zhang et al., 2006).
In view of the above, quite a number of natural materials of plant origin have long been used by local communities in many developing countries in water treatment. Some of the effective coagulants have been identified: Nirmali, Okra, Red beans, Sugar and Red maize (Gunaratna et al., 2007), and also Moringa oleifera (Jahn, 1988). Several extensive studies have been done on the use of these indigenous natural coagulants. Yongabi et al. (2011) studied the phytodisinfective and phytocoagulative activities of some plants in rural Cameroon which revealed that, H. sabdariffa seed and its calyx, M. oleifera, J. curcas and Pleurotus tuberregium scherotum lowered the turbidity of the water and the coliform count. The limited knowledge on the exact dosage and mechanism for usage renders them ineffective to compete favorably with the widely known synthetic chemicals. Also, the use of these plants in folk medicine and as a food makes them unlikely that they may contain any toxic substances (Jahn and Hamid, 1979). Plant coagulants can perform well if fully explored. The relationship between the botanical type and a content of coagulants (chemotaxonomy) could be detected for several plants genera and families. One of such families is the Hibiscus (malvaceae) family and a member of this family is hibiscus cannibinus Linn (kenaf).
2.2 Water Purification
Water purification is the removal of contaminants from raw water to produce drinking water that is pure enough for human consumption or for industrial use. Substances that are removed during the process include parasites (such as Giardia or Cryptosporidium), bacteria, algae, viruses, fungi, minerals (including toxic metals such as Lead, Copper etc.), and man-made chemical pollutants. Many contaminants can be dangerous—but depending on the quality standards, others are removed to improve the water’s smell, taste, and appearance.
A small amount of disinfectant is usually intentionally left in the water at the end of the treatment process to reduce the risk of re-contamination in the distribution system. Many environmental and cost considerations affect the location and design of water purification plants. Groundwater is cheaper to treat, but aquifers usually have limited output and can take thousands of years to recharge. Surface water sources should be carefully monitored for the presence of unusual types or levels of microbial/disease causing contaminants.
The treatment plant itself must be kept secure from vandalism and terrorism. It is not possible to tell whether water is safe to drink just by looking at it. Simple procedures such as boiling or the use of a household charcoal filter are not sufficient for treating water from an unknown source. Even natural spring water – considered safe for all practical purposes in the 1800s – must now be tested before determining what kind of treatment is needed.
1 – 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.
2 – 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.
3 – 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).
4 – 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.
2.3 Process in Water Purification
Most water used in industrialized countries is treated at water treatment plants. Although the methods those plants use in pretreatment depend on their size and the severity of the contamination, those practices have been standardized to ensure general compliance with national and international regulations. The majority of water is purified after it has been pumped from its natural source or directed via pipelines into holding tanks. After the water has been transported to a central location, the process of purification begins.
There are a number of methods commonly used to purify water. Their effectiveness is linked to the type of contaminant being treated and the type of application the water will be used for.
- Distillation: Oldest method of purification. Inexpensive but cannot be used for an on-demand process. Water must be distilled and then stored for later use, making it again prone to contamination if not stored properly.
- Activated carbon adsorption: Operates like a magnet on chlorine and organic compounds.
- Ultraviolet radiation: At a certain wavelength, this might cause bacteria to be sterilized and other micro organics to be broken down.
- Deionization: Also known as ion exchange, it is used for producing purified water on-demand, by passing water through resin beds. Negatively charged (cationic) resin removes positive ions, while positively charged one (anionic) removes negative ions. Continuous monitoring and maintenance of the cartridges can produce the purest water.
- Raw water is first collected in large aeration tank and the water is aerated by bubbling compressed air through perforated pipes.
- Aeration removes bad odors and CO2. It also removes metal such as iron, manganese by precipitating then as their respective hydroxides.
2. Storage or settling:
- Aerated water is then placed in settling tank and stored for 10-14 days.
- During storage about 90% of suspended solids settle down within 24 hrs and the water becomes clear.
- Certain heavier toxic chemicals also settle down during storage.
- Similarly pathogenic bacteria gradually die and bacterial count decreases by 90% in first in first 5-7 days of storage.
- During storage organic matter present in water is oxidized by microorganisms. Similarly NH3 present is oxidized into nitrate by microorganisms during storage.
- Water from storage tank is then placed in coagulation tank and then some precipitating agents such as alum, lime etc are added in water and mixed.
- These precipitating agents form precipitate of Al(OH)3 when dissolved in water.
- Suspended solids absorbs on the surface of precipitate, so gradually mass of precipitate becomes heavier and finally settle down.
- This technique is used to remove very light suspended solids that do not settle by themselves during storage. Furthermore, if negatively charged colloidal impurities are present, they are neutralized by Al+++ ions and settle down.
- Filtration: This process can take the form of any of the following:
- Coarse filtration: Also called particle filtration, it can utilize anything from a 1 mm sand filter, to a 1 micron cartridge filter.
- Micro filtration: Uses 1 to 0.1 micron devices to filter out bacteria. A typical implementation of this technique can be found in the brewing process.
- Ultra filtration: Removes pyrogens, endotoxins, DNA and RNA fragments.
- Reverse osmosis: Often referred to as RO, reverse osmosis is the most refined degree of liquid filtration. Instead of a filter, it uses a porous material acting as a unidirectional sieve that can separate molecular-sized particles.
- Partially clarified water is then passed through sand gravity filter which removes 98-99% of microorganisms and other impurities.
- Sand gravity water filter:
- Sand filter is a rectangular tank in which filter bed is made up to 3 layers.
- Top layer: fine layer of 1 meter thick
- Middle layer: 0.3-0.5 meter thick layer of coarse sand
- Bottom layer: 0.3-0.5 meter thick layer of gravel
- There is a collection tank at the bottom of the filter bed to collect filtered water. During filtration filter bed soon gets covered with a slimy layer called vital layer.
- Vital layer consists of thread like algae, diatoms and bacteria.
- During filtration microorganisms presents in vital layer oxidize organic and other matter present in water. For example if NH3 is present, it is oxidized into nitrate.
- Vital layer also helps in filtration of microbial cells.
- If water contains unpleasant odor, activated carbon may be placed in filter bed that removes bad odors.
- The filtered water is finally purified by using disinfectants. Eg. Chlorination
- Disinfectant kills pathogenic as well as other microorganism in water.
- After disinfection water is pumped into overhead tank for subsequent domestic distribution.
2.4 Types of Phyto Disinfectant
Native plants have traditionally been used to improve quality of water in many countries in Africa and Latin America. It has been reported that dried beans (Vicia fave) and peach seeds (Percica vulgaris) have been used in Bolivia and other countries in water treatment. Similarly, Schoenoplectus tatora, an aquatic plant has been used in Bolivia and Peru for Water Quality improvement. Biocoagulants from Moringa oleifera, Jatropha curcas, calyx of Hibiscus sabdarifa, sclerotium of Pleurotus tuberregium have been reported to show good coagulation activity too (Yongabi, 2011).
- Moringa oleifera: Moringa oleifera is the most widely cultivated species of a monogeneric family, the Moringaceae. It is a perennial softwood tree with timber of low quality, but which for centuries has been advocated for traditional medicinal and industrial uses. It is already an important crop in India, Ethiopia, the Philippines and Sudan, and is being grown in West, East and South Africa, tropical Asia, Latin America, the Caribbean, Florida and the Pacific Islands.
Moringa oleifera is an alternative, since their seeds contain a natural coagulant able to effectively reduce the turbidity of the raw water. Use of the seed as coagulant in water treatment is often performed as an aqueous extract but requires daily preparation in order to keep its clarification properties.
Thus, as a solution to the problem that has been stated, Moringa oleifera can be used as an alternative to replace synthetic aluminum to reduce the turbidity of the water and make it more suitable and safe to be consumed by humans. This study thus, was aimed to compare the efficiency of seed extracts of Moringa oleifera and aluminum sulphate in treating water that is used for drinking purposes.
All you need to do is crush the seeds and add it to water that you want to filter. This works because the crushed seeds clump together with debris and other types of foreign particles and sink all the way to the bottom. The water at the top of this mixture is left purified, clean and ready to drink. When crushed, the seed particles clump with debris and other foreign material in your water and sink to the bottom. Moringa seeds also lower bacterial levels in water.
2. Cilantro – Coriander
Coriander is a herb that can be used in purifying water. You can grind them and use it as a carbon filter by letting water pass through it. Alternatively, you can place some cilantro leaves in water and leave it overnight. This is an effective herbal water filter.
- Clearing Nut (Strychnos potatorum): The natural Strychnos potatorum (Nirmali seed) is widely used as coagulants to clarify turbid waters. In recent years natural and synthetically prepared organic Strychnos potatorums have been increasingly used in the coagulation of suspended matter in water and wastewater treatment. The natural coagulants extracted from plants or animals can be workable alternatives too synthetic Strychnos potatorums as they are biodegradable, safe to human health and have a wider effective dosage range for flocculation of various colloidal suspensions.
These nuts are extremely useful in removing sediments and turbidity from water. The purification is a unique process. You have to rub the insides of the storage vessel with these seeds. Fill the vessel with water and leave it for some time. The paste from these seeds is a natural coagulant thereby ensuring that the sediments settle down at the bottom.
- Household and Community Level water treatment units.
- Treatment Unit operations and processes.
- Existing conventional water treatment plants with slight modifications.
- New water treatment plants.
- Use processed Strychnos potatorum seed from medium technology or high technology.
- Provide manual of operation for dosing, filter maintenance etc.
- Strychnos potatorum seeds has water clearing and purifying capacity.
- It functions as a natural coagulant as well as antimicrobial agent for the treatment of ground drinking water source.
- Seed powder can be used in the rural areas where no other facility is available for purification of drinking water.
- As it is natural coagulant and microbicidal agent it does not have toxic effects on humans.
2.5 Methods of Phyto Disinfectant
Water purification using plants is a great natural method to treat mainly used water. Some plants have been proved to be excellent for water purification. Plants like the Prickly pear cactus (Opuntia ficus-indica), Moringa (Moringa oleifera), Nirmali (Strychnos potatorum), Tulasi (Ocimum sanctum) etc. have the capacity to purify water. The Opuntia ficus-indica was used for water purification by Mexican communities long back during the 18th and 19th century. Several plants have been still in use to treat contaminated water by the tribal communities.
Mucilage from the desert plants is glue like gummy substance which acts as a flocculant in water (e.g. Opuntia ficus-indica). It can precipitate substances into flakes and hence can remove substances like heavy metals (selenium, chromium, cadmium, arsenic etc.) and even bacteria from water. This thick gum is used by the plant to store water. When this gummy mucilage is added to water, it sticks to the particles and bacteria, which later sediments down to the bottom of the water. As per the new reports 98% of added bacteria were removed from the water sample.
However, experiments are yet to be carried out in natural water. Moringa Oleifera is a drought resistant tree which can grow on any types of soils including barren land. The seeds of this tree have coagulant properties and can purify turbid contaminated water. The seeds have to be crushed and the paste has to be mixed with water.
The water has to be left undisturbed for an hour. The paste coagulates suspended impurities like bacteria, dirt, soil particles, organic substances, etc. and makes water ready for domestic consumption. Dust and bacterial sediments which can be later are separated from pure water lying on the top. The protein component of these seeds acts as polyelectrolyte which can cross-link with charged particles.
Ocimum sanctum is a famous medicinal plant and finds a widespread application. The seeds of this plant are also known for their water purification properties. However, seeds can purify water up to a certain extent (seed size is too small) and make it palatable for domestic purposes. Strychnos potatorum plant seeds are also commonly used to clean water.
Aquatic plants contribute to purification of water by absorbing toxins into their root systems as nutrients and releasing important oxygen to further purification and for the bacterial colonies. Plants purify water by consuming excess nutrients and by deacidifying it by removing CO2. The important water purifying aquatic plants in natural conditions are Nymphea alba, Phragmites australis, Sparganium erectum, Iris pseudacorus, Schoenoplectus lacustris, Carex acutiformis etc.
Cactus and other plant products can be grown at many places at a lower cost. These plants can serve as a natural and renewable material for water filtration and at the same time save the lives of many people. It is a cost-effective alternative and also saves a lot of energy.
2.6 Application of Phytodisinfectant
There are about 2, 50,000 higher plants species on earth, out of these, more than 80,000 are medicinal (Joy et al., 1998). Sofowora (1982) reported that Africa has as much as 300, 000 medicinal plants. Historical accounts of traditionally used medicinal plants depict that different medicinal plants were in use as early as 5000 to 4000 BC in China, and 1600 BC by Syrians, Babylonians, Hebrews and Egyptians (Dery et al., 1999). Considerable indigenous knowledge system, from the earliest times, is found linked with the use of traditional medicine in different countries (Farnsworth, 1994). Beyond their human health and livestock treatments plants have been used historically for water treatment and there is evidence to suggest that communities in the developing world have used plant based materials as one strategy for purifying drinking water (Sarah et al., 2008). Therefore, natural coagulants and disinfectants can play a vital role for water sector that facing challenge today on how to give more people access to clean drinking water by cost effective means, especially the rural poor who cannot afford any water treatment chemicals, without affecting the health of their environment (Davy, 2001).
Plant species used as coagulant and disinfectant
In many rural communities of developing countries water clarification methods like flocculation, coagulation, and sedimentation are often impractical because of the high cost of equipment and low availability of chemical coagulants (Grabow et al., 1985). Natural plant extracts have been used for water purification for many centuries and Egyptians inscription afforded the earliest recorded knowledge of plant materials used for water treatment, dating back perhaps to 2000BC in addition to boiling and filtration (Fahey, 2005). In recent years there has been considerable interest in the development of usage of natural coagulants which can be produced extracted from microorganisms, animal or plant tissues. These coagulants should be biodegradable and are presumed to be safe for human health (Sciban et al., 2009). In addition, natural coagulants produce readily biodegradable and less voluminous sludge that amounts only 20– 30% that of alum treated counterpart (Narasiah et al., 2002).
The Moringa tree, sometimes referred to as the Indian miracle tree or Mother’s best friend, has long been known to offer amazing health benefits in its own right. Its leaves contain four times the Vitamin A of carrots, four times the calcium in milk, more iron than spinach, seven times as much vitamin C as oranges and three times the potassium in bananas, as well as more protein than either milk or eggs. But its use as a water purifier amounts to a new bonus again from one of the world’s most extraordinary trees. The seed kernels of M. oleifera contain significant quantities of low molecular-weight (water-soluble proteins) that carry a positive charge.
When the crushed seeds are added to raw water, the proteins produce positive charges acting like magnets and attracting the predominantly negatively charged particles (such as clay, silt, bacteria, and other toxic particles in water) [Sutherland et al., 1990]. Since bacteria in water are generally attached to solid particles, treatment with Moringa powder can leave water clear with 90 to 99% of the bacteria removed [Bukar et al., 2010].
The coagulative effect of M. oleifera seeds has been reported to be even better than Alum since M. oleifera seeds exhibited strong antimicrobial activity. [Yongabi et al., 2011]. In addition alum lowers the pH of the treated water and may cause stomach ulcers to those consuming such water. M. oleifera extract is not known to lower or raise the pH of the water by a significant value and it is therefore a better coagulant than alum [Arama et al., 2011]. The use of the plant in the treatment of drinking water has been known in a number of countries with reports of some using two grams of the crushed seeds to treat 20 L of water and obtaining about 90% reduction in turbidity and particles removal [Yongabi et al., 2011]. In Tanzania, water purification using this biocoagulant and disinfectant has been applied. The country has developed a procedure, which allows the large scale production of protein extracts from the seeds and press-cake of M. oleifera to evaluate its purified seed protein extracts as a potential substitute for inorganic coagulants used in water treatment processes [Schneider et al., 2006].
Studies carried out in Nyatike district of Nyanza province in Kenya have shown that both water soluble and ethanol soluble extract of M. oleifera seeds have activity against E. coli, the most common faecal water contaminant [Arama et al., 2011]. Locally the plant’s biocoagulant activity has been utilised. For instance a group of women from Kirinyaga district of Central Kenya purify water with the seed kennel for their domestic use and for other people at a fee. The purification process involves grinding M. oleifera seeds into a paste, mixing that paste with untreated water, waiting for the paste particles to bind with the impurities and settle to the bottom, and then decanting or siphoning the pure water off the top [FarmbizAfrica 2014].
Every coagulant is said to have its own optimal range of pH which affects the efficiency of their actions thus making pH an important parameter to be considered. The final pH reading for aluminum sulphate is below the permitted range of drinking water due to alkalinity consumption during hydrolysis by the coagulant. This is consistent with the results obtained from Jowa and Mguni, where they stated that aluminum sulphate is more acidic and hence its consumption of alkalinity is higher to prevent the water to become acidic. Sasikala and Muthuraman stated for the coagulation efficiency using Moringa oleifera, at pH acidic which is at less than 6 and also pH that is greater than 11, their coagulation efficiency is particularly good due to the domination of positive charges on the amino acids that build the protein molecule.
The trend of the reduction of both coagulants was seen to increased and decreased gradually due to the hydrolysis where the hydrogen ions are balancing out the hydroxide ions for both of the coagulants. But however, the most significant finding is the usage of aluminum sulphate was seen to reduce the pH of the groundwater sample to acidic, while for Moringa oleifera, the most significant finding of using Moringa oleifera is that they do not turns water into acidic as compared to when aluminum sulphate is used even though there are some readings that fall below the limit. The research conducted by Ndabigengesere et al. also reported the same findings as the current research where increased in dosage used for aluminum sulphate caused the pH to decrease drastically to pH reading, while Moringa oleifera does not affect the pH value significantly.
- Importance of Phyto Disinfectant
To improve the economical progress of developing countries, water contamination and spread of infectious diseases must be handled. This is achieved through (drinking) water treatment, sewage, waste and sewage water treatment and education on personal and food hygiene. Analysts say eliminating disease and death due to unclean water and poor sanitation would reap billions of dollars in health and productivity gains.
Natural plant extracts have been used for water purification for many centuries. Most of these extracts are derived from the seeds, leaves, pieces of bark or sap, roots and fruit extracts of trees and plants (Anwar and Rashid 2007), For example, Strychnos potatorum was being used as a clarifier between the fourteenth and fifteenth centuries BC. Shulz and Okun (1984) together with Sanghi et al. (2006) reported that seeds of the nirmali tree (Strychnos potatorum) were used to clarify turbid river water 4,000 years ago in India. It is further reported that in Peru, water has been traditionally clarified with the mucilaginous sap of tuna leaves obtained from certain species of cacti. Zea mays was used as a settling agent by sailors in the sixteenth and seventeenth centuries.
Natural coagulants have been reported to have several advantages compared to Alum (Aho and Lagasi 2012). Natural coagulants produce much lower sludge volume, the natural alkalinity is not consumed during the treatment process, they are biodegradable, safe to human health, cost effective since they can be locally grown and have a wider effective dosage range for flocculation of various colloidal suspensions (Sanghi et al. 2006). Moringa oleifera is medicinal species, belonging to monogeneric family Moringaceae (order Brassicales). It has 33 species of trees and shrubs distributed in sub-Himalayan ranges of India, Sri Lanka, North Eastern and South Western Africa, Madagascar and Arabia (Francis and Liogier 1991; The plant list, 2010). Today, it has become naturalised in many locations of the tropics and is widely cultivated in Africa, Ceylon, Thailand, Burma, Singapore, West Indies, Sri lanka, India, Mexico, Malabar, Malaysia and the Philippines (Fahey 2005).
Bacterial removal in the range of 90–99 % by the powder has also been reported (Madsen et al. 1987). Yongabi (2008) tested the coagulative and disinfective capabilities of M. oleifera, Jatropha curcas, Pleurotus tuberrregium sclerotium, Hibiscus sabdariffa and Alum on wastewater samples. M. oleifera coagulated about 90 % of the particles in the samples. The coagulation effect was superior in heavily polluted water than less polluted water. The number of coliforms also reduced substantially. It has been also used as water softener (Muyibi and Evison 1995).
The aim of drinking water treatment is to remove impurities and bacteria in order to meet the quality guidelines for drinking water (WHO 2004). M. oleifera seeds are recommended for eco-friendly, nontoxic, simplified water treatment where rural and peri-urban people living in extreme poverty (Mangale et al. 2012). Though previous studies reported the use of M. oleifera seeds for water purification, (Anwar and Rashid 2007; Broin et al. 2002; Kalogo et al. 2000; Kawo 2007) the seeds under study exhibited resistance to some of the waterborne pathogens (Onsare et al. 2013). In this regards, an effort has been made to establish a database of the naturally occurring coagulant that has been used for water purification and also to carry out preliminary tests on the performance of plant extracts available in Ethiopia on shallow well water.
Cofie, and Keiaita, (2003) in Proceedings of the 29th WEDC International Conference, Abuja-Nigeria, highlighted the following importance of phytodisinfectant in water purification:
- Lower Bacteria Levels: coli and other bacteria can cause serious illnesses when you’re exposed to them in your drinking water. While some of these bacteria might cause mild symptoms, such as nausea, others can be life-threatening, especially in children, older adults and those with conditions that lower their immunity. A Charlotte water purification system helps ensure that your drinking water is free of these potentially dangerous types of bacteria.
- Cost Savings: Purchasing bottled water provides your household with water that does not contain contaminants, but the cost of buying these bottles can add up significantly over time. Investing in a water purification Charlotte system leads to a lower amount of money spent on having clean water. This can add up to considerable cost savings in the long run.
Reduced Chlorine Levels: Chlorine in drinking water can cause a wide range of serious health issues. These include the following:
- Higher risk of cancer
- Cardiovascular problems
- Birth defects
- Lower Cancer Risk: Chemicals and other toxic materials can make their way into water sources, which increases the risk of getting some types of cancer. Eliminating these through water purification might help lower your risk of getting cancer that is associated with exposure to these materials.
- Fewer Plumbing Contaminants: If you live in an older home, your pipes and plumbing system can introduce copper and other contaminants into your water supply. Even though your local water supply is treated, these contaminants are able to enter your home as water flows through old, corroded pipes. Purifying your water helps keep these materials out of your drinking water.
- Summary, Recommendations and Conclusion
Clean water is a critical resource, rapidly becoming scarce because growing populations are consuming more and reducing supply through pollution. Filtering, treating, and otherwise cleaning wastewater to increase supply is necessary, but these methods are expensive and require excessive energy. Modern treatment processes are decidedly not organic, often requiring additional chemicals to be added to the water (e.g., chlorine.) (Faust, 1998) I hypothesized that natural filters utilizing plants and their associated growth media (and microflora) could filter common household pollutants from wastewater. While not yielding potable water, the filtered water might be clean enough to release safely into the environment or reuse (e.g., to flush a toilet or wash a car). A natural filter has many benefits and could be a future alternative for water filtration.
Finally, I believe the plants in both biofilters played a great role in removing phosphates, nitrates, nitrites and ammonia. Many substances harmful to people and animals are conducive to plant growth. Plants require ammonia, phosphates and nitrates, and most synthetic fertilizers (as well as laundry detergent) contain these chemicals. However, high concentrations of these chemicals can cause algae or other plant species to “bloom,” disrupting the environmental balance, and sufficiently high concentrations can kill the same plants. Duckweed, nut grass and water lilies are known to absorb these substances, and lily pads are planted in many ponds to control algal blooms. (Peteducation.com 2011) Duckweed expands and spreads as it gains phosphates, as do water lilies. In addition to absorbing chemicals useful to them, certain plants can “lock up” harmful substances such as lead, zinc and cadmium, preventing them from harming other species or getting into the groundwater.
- Natural materials available in many communities should be used to treat water for drinking. Additionally.
- Plant materials should be applied in the treatment of any type of polluted water.
- These materials are low cost when compared to the application of synthetic chemicals in water pollution management. Therefore, pilot system applying natural materials in water treatment could be adopted and replicated everywhere.
- There is a need to develop a localised water purification system so that rural villages can use plant extracts to improve their drinking water quality from shallow wells.
- More research into the use of natural materials in water pollution management should be studied.
This seminar work has conclusively indicated that water can be treated considerably with the application of phyto-disinfectants. This work has also shown that there are many plants that need to be screened properly for water treatment. There is need to exploit the potential of plants which may offer cheap, and environment friendly methods of tackling water contamination and may possibly overcome the hazards of using synthetic compounds. From this study, further studies on the actual application of Moringa oleifera seeds in water purification at household or large scale level is required.
Anwar F, Rashid U (2007) Physico-chemical characteristics of Moringa oleifera seeds and seed oil from a wild provenance of Pakistan. Pak J Biol Sci 39:1443–1453
Broin M, Santaella C, Cuine S, Kokou K, Peltier G, Joet T (2002) Flocculent activity of a recombinant protein from Moringa oleifera Lam. Seeds. Appl Microbiol Biotechnol 60:114–119
Chand Rashmi, Bremnerh.David, Namkungc.Kyu, Collier J.Philips, Gogetr.Parag (2007); Wqater Disinfection The Novel Approach Of Ozone And A Liquid Whistle Reactor, Biomedical Engineering Journal, Vol.35, Issue 3, Pp 357-364.
Cofie, O. and Keiaita, B. (2003) Environmental Sanitation and Urban Agriculture in Ghana. Proceedings of the 29th WEDC International Conference, Abuja, Nigeria.
Dzwairo B, Hoko Z, Love D, Guzha E (2006) Assessment of the impacts of pit latrines on groundwater quality in rural areas: a case study from Marondera district, Zimbabwe. Phys Chem Earth J 31:779–788
Fahey JW (2005)Moringa oleifera: a review of the medicinal evidence for its nutritional, therapeutic and prophylactic properties. Trees life J 1:5
Francis JK, Liogier HA (1991) Naturalized exotic tree species in Puerto Rico. USDA Forest Service General Technical Report SO-82, Southern Forest Experimental Station, (New Orleans, LA, USA), p 12.
Gagnon G.A., Rand J.L., O’rygel A.C., Chauretc.,Andrews R.C. (2005).Disinfectant Efficacy Of Chlorine And Chlorine Dioxide In Drinking Water Biofilms. Water Research 39.Pp 1809-1817.
Gunnel D (2005). A simple Purification and activity assay of the coagulant protein from Moringa oleifera seed. Water Res., 39: 2338-2344.
Jamil A, Shahid M, Khan MM, Ashraf M (2007) Screening of some medicinal plants for isolation of antifungal proteins and peptides. Pak J Bot 39:211–22.
K.A Yongabi (2004). Studies on the use of Medicinal Plants and Macro fungi (lower plants) in water and wastewater purification. Tre for life Journal, Proceeding of an E- Seminar organized by the International organization for biotechnology and Bioengineering June 1-24, pp1-14.
Kalogo Y, Rosillon F, Hammer F, Verstraete W (2000) Effect of a water extract of Moringa oleifera seeds on the hydrolytic microbial species diversity of a UASB reactor treating domestic wastewater. Lett Appl Microbiol 31:259–264.
Kawo AH (2007) Water purification potentials and in vivo toxicity evaluation of the aqueous and petroleum ether extracts of Calotropis procera, Latex and Moringa oleifera Lam seed powder. PhD thesis, Microbiology Unit, Department of Biological Sciences, Bayero University.
Kebreab AG, Gunaratna KR, Henriksson H, Brumer H, Dalhammar GA (2005) Simple purification and activity assay of the coagulant protein from Moringa oleifera seed. Water Res 39:2338–2344.
Litherland S (1995) Science: vegetable pods may help solve third world’s water woes. Inter Press Service, Washington, DC.
Lockett CT, Calvet CC, Grivetti LE (2000) Energy and micronutrient composition of dietary and medicinal wild plants consumed during drought: Study of rural Fulani, Northeastern Nigeria. Int J Food Sci Nutr 51:195–208.
Lungu K, Morse T, Grimason AM (2008) Ecological sanitation—implementation opportunities and challenges in Chikwawa, Malawi. Environment and Health International. Magazine of the International Federation of Environmental Health, Congress 10(2):1–7.
Madsen M, Schlundt J, Omer EFE (1987) Effect of water coagulation by seeds of Moringa oleifera on bacterial concentrations. J Tropol Med Hyg 90:101–109.
Mangale SM, Chonde SG, Jadhav AS, Raut PD (2012) Study of Moringa oleifera (Drumstick) seed as natural absorbent and antimicrobial agent for river water treatment. J Nat Prod Plant Resour 2(1):89–100.
Masangwi SJ, Morse T, Ferguson G, Zawdie G, Grimason AM, (2008) A preliminary analysis of the Scotland-Chikwawa health initiative project on morbidity. Environment and Health International. Magazine of the International Federation of Environmental Health, Congress 10(2):10–22.
Muyibi SA, Evison LM (1995) Moringa oleifera seeds for softening hard Water. Water Res 29(4):1099–1105.
Ng SC, Katayon S, Megat Mohd Noor MJ, Asma M, Abdul Ghani LA, Thamer AM, Azni I, Ahmad J, Khor BC, Suleymen AM (2006) Effects of storage conditions of Moringa oleifera seeds on its performance in coagulation. Bioresour Technol 97:1455–1460.
Onsare JG, Kaur H, Arora DS (2013) Antimicrobial activity of Moringa oleifera from different locations against some human pathogens. Acad J Med Plants 1(5):080–091.
Prasad RK (2009). Color removal from distillery spent wash through coagulation using Moringa oleifera seeds: Use of optimum response surface methodology. J. Hazardous Mater., 165(1-3): 804-811.
Pritchard M, Mkandawire T, O’Neill JG (2008) Assessment of groundwater quality in shallow wells within the Southern districts of Malawi. Phys Chem Earth J 33:927–935.
Schneider M., Marison I.W., Mbwette T. S., Katima J.H., Hassanali A., (2006). Drinking Water Treatment in Tanzania Using Seed Protein Extracts from the Pan-Tropical Tree Moringa oleifera Lam. Laboratory of Chemical and Biological Engineering (LGCB) of the Swiss Federal Institute of Technology in Lausanne (EPFL) project. http://www.northsouth.ethz.ch/ accessed on 2nd Dec. 2014.
Shirude A.A. (2011); Phytochemical And Pharmacological Screening Of Wheatgrass Juice (Triticumaestivum L.), International Journal Of Pharmaceutical Science Review And Research, Vol. 9, Issue1, Pp 159-164.
Sunil B.Somani, Nitin W. Ingole, Shrikant S. Patil (2011); Performance Evaluation Of Natural Herbs For Antibacterial Acivities In Water Purification.International Journal Of Engineerimg Science And Technology, Vol.3 Pp. 7170-7174.
UNESCO (2007). UNESCO Water Portal Newsletter No.161: Water- related Diseases.
White G.C. (1992): The Handbook Of Chlorination And Alternative Disinfectants. 3rd Edition, Van Nostrnd Reinhold. New York. Pp 290-478.
WHO (1990): The International Drinking Water Supply and Sanitation Decade: Review of decade progress: Geneva.
Yongabi K. A. (2011). Application of phytodisinfectants in water purification in rural Cameroon. African Journal of Microbiology Research 5(6), 628-635.
Yongabi, K.A (2009). The Role of Phytobiotechnology in Public health: In Biotechnology Ed.Horst.W.Doelle Edgar.J.Dasilva in Encyclopedia of life support Systems (EOLSS) developed under the auspices of the UNESCO EOLSS publishers, Oxford, UK.
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