Guided By: Rashmi VipatSusmita Gawde Sayali Gharat TIMSCDR TIMSCDR
Abstract: “How will waste be managed?” is an important question demanding attention due to the rapid growth in waste generation worldwide. With the ever-increasing population and consumerist lifestyle generate voluminous solid wastes. Large quantities of organic wastes are produced from agricultural production and farming systems, including animal manures, food and kitchen wastes, and industrial organic wastes. These have the potential of increasing global soil and water pollution because they are currently disposed of by land-spreading, or into landfills. As much as 50%–60% of the total wastes that are disposed into landfills are organic wastes. If these wastes are turned into materials useful in agriculture and horticulture, there would be great savings in primary plant nutrients. Vermicompost have a higher level of available nutrients like carbon nitrogen, phosphorous and potassium, calcium and magnesium derived from the wastes. The use of earthworms in the degradation of different types of wastes is continuing from the past so many years. These wastes include industrial, agricultural of plant debris and domestic waste papers and kitchen waste. The paper has attempted to evaluate the development of vermicomposting technology in different types of wastes such as industrial, agricultural, paper wastes, bio-degradable waste from the kitchen.
Keywords: Vermicomposting, Sludge, Earthworms, Waste Management, Compost.
Today’s population is increasing very fast, as it causes a quantity increase and type of rural as well as urban waste. Such wastes are pollutants to the environment. Until the rural wastes are concerned, there will be vast quantities of organic materials available that are not utilized. Vermicomposting Technology is a fast growing one with its pollution free, cost and nature efficient. Vermicomposting known as a process of transformation of biodegradable matter by earthworms in vermicast. This process is about, conversion of nutrients contained in the organic matter that partially converted into more bioavailable forms. Vermicast is believed to have hormones and enzymes in it which it acquire during passage of organic matter by the earthworm’s gut.
Food processing industries produces large quantities of liquid as well as solid waste and event their treatment results in generation of sledges. This sludge are disposed of in open dumps or poorly organized landfills which costs public health and environment hazards by ground water pollution. These indiscriminate disposal method lead to the loss of nutrient resource. Industrial waste could be suitable substrates vermicomposting. Different industrial sludge’s tested for vermicomposting consist of paper mill sludge, textile mile sludge. From the survey it is proved that there is paucity of data on vermicomposting of food industry, waste water treatment and plant sludge. At the end, vermicast is believed to be good organic fertilizer and also has more beneficial impact on plants, compost as well as waste water.
VERMICOMPOST PROCESS FACTORS
Vermicompost is the product of the composting process which uses various types of earthworms and other types of worms like red wigglers, white worms, to create a mixture of decomposing waste, bedding materials, and vermicast. The basic for the process of vermicomposting are:
Bedding is any material that provides a relatively suitable environment for worms. For good vermicomposting, this environment should satisfy the following criteria:
High absorbency: The worms breathe through the skin, so the bedding must be able to absorb and retain adequate water.
Good bulking potential: The bulking potential of the material should be good enough so that worms get oxygen properly.
Low nitrogen content: High protein/nitrogen levels can result in rapid degradation and associated heating may be fatal to worms.
Feeding the earthworms regularly is the most essential step in the vermicomposting process. Earthworms can use a wide variety of organic materials. In worst conditions, earthworms can extract sufficient nourishment from soil to survive. However, earthworms feed mainly on dead and decaying organic waste and on free-living soil microflora and fauna. Worms can consume the amount of food higher than their body weights. Livestock, for example, goat manure, cattle dung or pig manure are the most commonly used worm feedstock as these materials have higher nitrogen content. From the waste ingested by the worms, 5-10% is being used by the worm’s body and the rest is being excreted in the form of vermicast.
Adequate moisture is the most important requirement of earthworms. They require moisture around 60-70%. The feedstock given to worms should not be too wet otherwise it may create anaerobic conditions which may be fatal to earthworms.
Factors such as high levels of fatty/oily substances in the feedstock or excessive moisture combined with poor aeration may create anaerobic conditions in the vermicomposting system. Worms may suffer severe mortality because they are deprived of oxygen or because of toxic substances. This is one of the main reasons for not including meat or another fatty/oily wastes in worm feedstock.
Many factors such as activity, metabolism, growth, respiration, and reproduction of earthworms are greatly influenced by temperature. Most earthworm species used in vermicomposting require moderate temperatures from 10 – 35 degree Celsius. Tolerances and preferences vary from species to species. Earthworms can tolerate cold and moist conditions far better than hot and dry conditions.
Worms can survive in a pH range of 5 to 9, but a range of 7.5 to 8.0 is considered to be the optimum. In general, the pH of worm beds tends to drop over time due to the fragmentation of organic matter under a series of chemical reactions.
Composting can be done either in pits or concrete tanks or well rings or in wooden or plastic crates depending on the situation and amount of waste. It is preferable to select a composting site under shade, in the elevated level, to prevent water stagnation in pits during rains. Vermicomposting is set up by first placing a base layer of vermibed comprising broken bricks or pebbles (3-4 cm.) followed by a layer of coarse sand to a total thickness of 6-7 cm. To ensure proper drainage, a 15 cm moist layer of loose soil put upon. Into this soil 100 earthworms are inoculated. Then fresh or dry cattle dung then scattered over the soil and covered with a 10cm layer of hay. Water is sprayed till the entire set up is moist. Too much water will chase the worm away while less water will kill them. The unit is then waters and monitored for 30 days.
From the 31st day, organic refuse is spread on top. Refuse can be added twice a week, and watered as per requirement. After a few applications, the refuse is turned over without disturbing the bed. When enough refuse has been added into the unit, the watering is continued and 45 days later the compost is ready for harvest. Finally, the organic refuse changes into a soft, spongy, sweet smelling, dark brown compost
VERMICOMPOST TECHNOLOGY FOR SOLID WASTE MANAGEMENT
Solid waste is defined as the organic and inorganic waste materials produced by different sources and has lost value in the eye of their ownerRP8. It has been estimated that India, as a whole, generates as much as 25 million tons of different solid waste per year.
Solid waste management is one of the major environmental problems. Improper management of solid waste causes hazards to inhabitants. Many studies reveal that about 90% of solid waste is disposed of unscientifically in open dumps and landfills, creating problems for public health and the environment. There are many categories of solid waste such as food waste, commercial waste, rubbish institutional waste, industrial waste, construction waste, and sanitation waste. The solid waste contains recyclables like paper, plastic, glass, metals, etc., toxic substances like paints, pesticides, used batteries, medicines etc., compostable organic matter like fruit and vegetable peels, food waste and soiled waste like blood-stained cotton, sanitary napkins, disposable syringes etc.
The quantity of solid waste generated depends on a number of factors such as food habits, a standard of living, the degree of commercial activities etc. Vermicomposting involves stabilization of organic waste through the combined action of earthworms and aerobic microorganisms. Initially, microbial decomposition of biodegradable organic matter occurs through extracellular enzymatic activity (primary decomposition). Earthworms feed on the partially decomposed matter, consuming five times their body weight of organic matter per day. The food ingested by the worms is further decomposed in their gut, which results in particle size reduction. The worm cast is very fine, odorless and granular product. The resulting product can serve as a biofertilizer in agriculture.
VERMICOMPOST TECHNOLOGY FOR PAPER WASTE MANAGEMENT
Organic wastes are usually described as paper pulp solids or sludges. Paper sludge can be used as a bulking agent or great source of carbon in composting. Sludges from paper mill industries cannot be used as a feeding material of epigeic earthworms. In composting experiment first plastic container gets filled with the pre-decomposed mixture of cow dung and shredded paper. 20-25 mature, clitellate worms are taken and uniformly released on the top of the containers of all the three experimental containers. The experiments should conduct inside the vermicompost hut, in order to avoid the danger of predators and rain during the months of Jul and Sep. The containers are then covered by mesh garden cloth and observed daily to check the various parameters necessary for the survival and reproduction of earthworms. This complete setup is maintained for 60-65 days till the finely granular vermicompost is prepare. The process of vermicomposting significantly modify the physical and chemical properties of the paper waste material which can be an important tool for organic farming.
VERMICOMPOSTING TECHNOLOGY FOR FOOD INDUSTRIAL SLUDGE MANAGEMENT
Food processing is emerging among the most important industrial activities in recent years. There is a large number of food industries operating at different scales large to small. Food processing industries produce liquid and solid wastes in huge amount and their treatment results into the generation of sludges. But the great challenge to industries is the economical and ecologically acceptable disposal of industrial sludges due to the high cost of sludge stabilization reactors, dehydration systems, and transportation of sludge to disposal sites. Industrial sludge is generally disposed of in open dumps or poorly designed landfills causing public health and environmental hazards by surface and groundwater pollution.
Industrial wastes that are rich in organic matter and free from toxic substances could be suitable for vermicomposting. Several pieces of research have been conducted on the potential use of earthworms in nutrient recovery from food industrial sludges. It has been observed that epigeic forms of earthworms can produce a better quality of vermicompost as compared with those prepared through traditional composting methods. Various industrial sludges tested for vermicomposting include solid paper mill sludge, textile mill sludge, etc.
The vermicomposting of food industrial sludges benefits two major factors: a waste is converted into a value-added product, and, it controls a pollutant that is a consequence of increasing industrialization. After the addition of food industry sludge in appropriate quantities to the cow dung, it can be used as a raw material in the vermicomposting. For the processing of food industry sludge, it is necessary to process other waste materials. The resulting vermicompost shows higher NPK content.
VERMICOMPOSTING TECHNOLOGY FOR FLOWER WASTE
Vermicomposting is one of the environmental friendly technologies for flower waste management since it outstrips the problem of organic waste disposal and also prevents the odor problem. In the process of flower waste vermicomposting, flower waste and cow dung are mixed equally (5kg each). Alternate two layers each of farm waste, floral waste and cow dung are placed over one another. About 200 to 250 of earthworms will be gained into partially digested material stored in a vermibed and moisture level is maintained at 56 percent. Watering is done till the contents heat is satisfactorily reduced. For that watering will be continuing around 2 days. When the composting process is over that is after the 45th day the worms weight increased by 85 %. The amount of finished vermicompost obtained is 2.57 kg. Vermiwash produced is collected and kept in the container. Vermiwash diluted with water is sprayed on plants as anti-fungous nutritious effective.
ADVANTAGES OF VERMICOMPOSTING
The vermicomposting of organic waste is very simple. Worms ingest the waste material – they break it up – consume the digestible portion, and then excrete the remaining humus-like material that can be marketed and has a variety of documented benefits to the consumer.
Vermicomposting technology can be a promising technique that has shown its potential in certain challenging areas like food industry waste management, waste recycling, management of solid wastes etc. It can be very useful in India, where on one side pollution is increasing due to accumulation of organic wastes and on the other side there is shortage of organic manure, which could increase the fertility and productivity of the land and produce nutritive and safe food. So the scope for vermicomposting is enormous in India.
The availability of nutrients is generally higher in vermicompost than in the traditional compost and inorganic fertilizer, indicating that vermicompost is a better supplement to improve and stimulate plant growth. Thus vermicompost has a huge potential for use on agricultural crops. In the near future, vermicompost should be largely and extensively applied to agricultural land to replace or, alternatively, combine with inorganic fertilizers. Vermicompost is shown to improve soil fertility in terms of physical and chemical properties of the soil. Chemical properties such as pH and organic carbon content are also enhanced for better plant growth.
Vermicomposting is a process for handling organic residuals, it represents an alternative approach in waste management, and the material is neither landfilled nor burned but is considered a resource that can be recycled. Vermicomposting is compatible with environmental principles that value conservation of resources and sustainable practices.