Presentation is loading. Please wait.

Presentation is loading. Please wait.

VERMIFILTRATION

Similar presentations


Presentation on theme: "VERMIFILTRATION "— Presentation transcript:

1 UTTARANCHAL UNIVERSITY SCHOOL OF APPLIED AND LIFE SCIENCES VERMIFILTRATION Prepared By:Ravindra Kr. Kachhap Oraon

2 VERMIFILTRATION Many developing countries or Nations cannot afford the waste water treatment As they are costly need more space to construct the treatment plant and in addition use of chemicals for the treatment.

3 VERMIFILTRATION Vermifiltration is a new Technique approach towards wastewater treatment to save cost,energy and eliminate chemical usage. Vermifiltration needs no external energy, except pumping. It’s a known biotechnological aerobic process of treatment of waste water which is carried out with the use of epigenic earthworms.

4 VERMIFILTRATION Earthworms body work as a 'biofilter' and they have been found to remove the 5 days BOD by 90%,COD by 80-90%,TDS by 90- 92% and TSS by 90-95% from wastewater by the general mechanism of 'ingestion' and biodegradation of organic wastes,heavy metals and solids from wastewater and also by absorbation through body walls.

5 Earthworm The earthworms have around 600 million years of experience in waste and environmental management. Charles Darwin called them as the “unheralded soldiers of mankind”, and the Greek philosopher Aristotle called them as the “intestine of earth”, meaning digesting a widevariety of organic materials including the waste organics, from earth. [7, 8] Earthworms are long, cylindrical, narrow, bilaterally symmetrical, segmented animals without bones. The body is dark brown, glistening, and covered by all of delicate cuticle. They weigh around 1,400–1,500 mg after 8–10 weeks.

6 Earthworm On an average, 2,000 adult worms weigh 1 kg and one million worms weigh approximately 1 ton. Usually the life span of an earthworm is practically 3–7 years depending upon the type of species and the ecological situation. Earthworms nourish millions of nitrogen-fixing and decomposer microbes in their gut. They have chemoreceptors which help in search of food. The distribution of earthworms in soil depends on factors like availability of organic matter, soil moisture and pH of the soil. They develop in different habitats especially those which are dark and moist.

7 As worms breathe through their skin significant ventilation of air in soil medium is necessary. They can tolerate a temperature range between 5 and 29˚C. A temperature of 20–25˚C and moisture of 60– 75% are optimum for good worm function. Earthworms are bisexual animals and multiply literally rapidly. The total life cycle of the worms is closely around 220 days. They produce 300–400 young ones within this life period. Earthworms are very sensitive to light, touch, and dryness. Low temperature is not a big problem for them as the high temperature. Their movement is significantly slowed down in winter, but heat can kill them instantly

8

9

10

11 Hydraulic retention time (HRT) is a measure of the average length of time that a compound (in this case wastewater) remains in a treatment tank or unit The volume of the aeration tank divided by the influent flowrate is τ (tau), the hyraulic retention time. Hydraulic loading rateHydraulic loading rate means the rate at which wastes or wastewaters are discharged to a land disposal or land treatment system, expressed in volume per unit area per unit time or depth of water per unit area per unit. Biochemical oxygen demand (BOD) represents the amount of oxygen consumed by bacteria and other microorganisms while they decompose organic matter under aerobic (oxygen is present) conditions at a specified temperature.

12 The chemical oxygen demand (COD) is a measure of water and wastewater quality. The COD test is often used to monitor water treatment plant efficiency. FAS – Ferrous Ammonium Sulfate

13 Mechanism of action of earthworms in Vermifiltration of wastewater Microbes present in the gut of earthworms and enzymes present in secreted coelomic fluid stimulate biodegradation process. The sand and pebble layers of the vermifilter unit also provide a wonderful site for the growth of aerobic microbes. The pollutants in wastewater are adsorbed and stabilized by the earthworms and the aerobic microbes excreted from the gut of earthworms. The vermicast offers excellent ‘hydraulic conductivity’ in vermifilter layers because of being porous-like sand for cleaning sewage. Coelomic fluid also degrades harmful and ineffective microbes from wastewater thus preventing choking of the medium. (Sinha et al. 2012)

14

15 Materials: Vermicomposting tanks can be made from local materials (bricks or concrete). Vermifilters require enclosed reactors made from durable materials that eliminate vermin entry, usually plastic or concrete. Filter material for the vermifilter can be sawdust, straw, coir, bark mulch or peat. Worms are required, and three species to date have been successfully used: Eisenia fetida, Eudrilus eugeniae and Eisenia andrei. It is possible to find worms in the local environment, buy them from vermicomposting or vermifilter businesses or import them. Prefabricated composting vessels of different sizes are available on the market.

16 Methods 1. Wastewater Physicochemical Properties Analyzed The untreated sewage wastewater was fed to the vermifilter bed as well as the control bio-filter bed and allowed to move through the bed. The treated sewage water was then collected at the bottom of the vermifilter bed and was analyzed for pH, BOD5, COD, TDSS and turbidity. The pH was measured by the Hanna Instrument which was allowed to settle for 10 minutes before measurement. The BOD5 was determined by the standard oxidation procedure after 5 days at 20 ◦ C whilst the COD and turbidity were also determined by a uv-vis spectrophotometer according to procedures clearly explained in detail by Sinha et al., [6] The TDSS was determined by filtration and the amount of solids removed was determined by drying at 100°C.

17 2. The Vermifiltration Experimental Procedure 5L of sewage wastewater was kept in calibrated 8L poly vinyl chloride (PVC) drum. The drum was kept on an elevated platform just near the vermifilter bed. The PVC drum had a tap at the bottom to which an irrigation system was attached. The irrigation system consisted of a 1.3 cm polypropylene pipe with 2mm holes for trickling water that allowed uniform the distribution of wastewater on the soil surface of the vermifilter bed.

18 Wastewater from the drum flowed through the irrigation pipe by gravity at a rate of 0.003m3/hr. The wastewater percolated down through various layers in the vermifilter bed passing through the soil layer inhabited by earthworms, the sandy layer, the gravel, and at the end was collected in a chamber at the bottom of the vermifilter bed. The hydraulic retention time (HRT) in the vermifilter bed was kept uniformly at 2 hours in all experiments and each experimental run was allowed to go through 2 cycles. All experiments for both the vermifilter and the control bio-filter were replicated 3 times.

19 3. The Control Bio-Filter Bed Experiment The control bio-filter bed, without earthworms was set as a comparison to evaluate the effect of earthworms as bio- filters in wastewater treatment. The control bio-filter bed was an exact replica of the vermifiltration bed but had no earthworms added to it. The soil, sand particles and the gravels in the control bio-filter bed are reported to also contribute in the filtration and cleaning of wastewater by adsorption of the impurities on their surface [2-4, 6]. Soil, sand and gravel particles provide ideal sites for colonization by decomposer microbes which work to reduce BOD, COD, TDSS and the turbidity from the wastewater [2-4, 5-6]. When the wastewater passed through the beds, a layer of microbial film was produced around them and together they constituted the geological and the microbial system of wastewater filtration [2-4, 6]. Increase of the volume of wastewater passing through the soil filter also increases formation of biofilms of decomposer microbes [2-4, 5-6]. Hence it is critical to have a control bio-filter bed to determine the effect of earthworms

20 Uttranchal University

21 Vermifiltration treatment is low energy dependent and has distinct advantage over all the conventional biological wastewater treatment systems- the Activated Sludge Process, Trickling Filters, and Rotating Biological Contactors which are highly energy intensive, costly to install and operate, and do not generate any income. In the vermifilter process there is 100% capture of organic materials, the capital and operating costs are less, and there is high value added end product (vermicompost). sludge is discharged in the vermifilter bed as excreta (vermicompost) which is useful soil additive for agriculture and horticulture ADVANTAGES OF VERMIFILTRATION 1 2 3

22 There is no foul odor as the earthworms arrest rotting and decay of all putrescible matters in the wastewater and the sludge. Large quantities of worm biomass will be available as food for the cattle, poultry, and fish farming, after the first year of vermitreatment. It can utilize waste organics that otherwise cannot be utilized by other technologies. vii. Achieve greater utilization of waste materials that cannot be achieved by other technologies. ADVANTAGES OF VERMIFILTRATION 4 5 6

23 References 1] Sinha RK, Chandran V, Soni BK, Patel U, Ghosh A (2012) Earth-worms: nature’s chemical managers and detoxifying agents in the environment: an innovative study on treatment of toxic waste- waters from the petroleum industry by vermifiltration technology. Environmentalist 32(4):445–452. https://doi.org/10.1007/s10669-012-9409-2 [2] R. K. Sinha, G. Bharambe and P. Bapat, “Removal of high BOD and COD loadings of primary liquid waste products from dairy industry by vermifiltration technology using earthworms”, Indian Journal of Environmental Protection, 27 (6), pp. 486-501, 2007. [3] R. K. Sinha, S. Agarwal, K. Chauhan, V. Chandran and B. K. Soni, “Vermiculture technology: Reviving the dreams of Sir Charles Darwin for Scientific Use of Earthworms in Sustainable Development Programs,” Technology and Investment, 1, pp. 155-172, 2010. [4] R. K. Sinha, K. Chauhan, D. Valan, V. Chandran, B. K. Soni and V. Patel, “Earthworms: Charles Darwin’s unheralded soldiers of mankind: Protective and Productive for Man and Environment”, Journal of Environmental Protection, 1, pp. 251-260, 2010. [5] S. D. Ghatnekar, M. F. Kavian, S. M. Sharma, S. S. Ghatnekar, G. S. Ghatnekar and A. V. Ghatnekar, “Application of vermi-filter-based effluent treatments from the gelatine industry”, Dynamic Soil, Dynamic Plant, pp. 83-88, 2010. [6] S. A. Azuar and M. H. Ibrahim, “Comparison of sand and oil palm fibre vermibeds in filtration of palm oil mill effluent (POME)”, UMT 11th International Annual Symposium on Sustainability Science and Management, 09th-11th July 2012, Terengganu, Malaysia, pp. 14141419, 2012. [7] Darwin F and Seward AC, “More letters of Charles Darwin. A record of his work in series of hitherto unpublished letters.” John Murray, London, (1903), vol. 2, pp. 508. [4] Darwin F and Seward AC, “More letters of Charles Darwin. A record of his work in series of hitherto unpublished letters.” John Murray, London, (1903), vol. 2, pp. 508. [8] Martin JP., “Darwin on earthworms: the formation of vegetable moulds.” Bookworm Publishing, ISBN (1976) 0-916302-06-7. [9] Hand P., “Earthworm biotechnology.” In: Greenshields R (ed) Resources and application of biotechnology: the new wave. MacMillan Press Ltd, US (1988).

24


Download ppt "VERMIFILTRATION "

Similar presentations


Ads by Google