Vol 2 _1_ - Cont. J Water, Air and Soil Pollution - Wilolud Journals

Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011© Wilolud Journals, 2011 http://www.wiloludjournal.com` Printed in NigeriaMATERIAL RECOVERY FROM POLYTHEHE RECYCLE AS AN ENVIRONMENTALPOLLUTANT IN NIGERIAUkpong, E. C and Peter, Chamberlain M.Civil Engineering Department, University of Uyo, Uyo, Akwa Ibom State, NigeriaABSTRACTThis study investigates the environmental pollution caused by polyethylene (cellophane) material inNigeria. Polyethylene was generated using two methods, one at the market place and the other at home.Fifty respondents in the market were given two waste baskets each to determine the rate and type ofcellophane generation and disposal. It was found that the dry season months of (November to March)are higher in the generation and disposal of this material than the wet season months of (April toOctober). Based on the type of cellophane, table water sachet topped the list followed by cellophane forassorted items, ice cream and biscuit wrappers in that order. polyethylene generation was higher in themarket than at home. Cheapness and availability are some of the reasons for constant patronage ofcellophane. Indiscriminate polyethylene disposal has constituted environmental nuisance anddegradation, it was also seen that during the course of this study that polyethylene waste that wasdumped into the soil for decades makes an engineering soil difficult to work on during excavation oftop (vegetable) soil or foundation. For cleaner and sustainable environments, vigorous enlightenmentcampaign, proper collection techniques and recycling among others are recommended.KEYWORDS: Cellophane, pollution, market, home, disposal, basket.INTRODUCTIONPolythene materials are used widely in many consumer products, they are low performance products likewrapping products, storage of beverages, toys and also high performance products like car components, bulletproof suits and other products. They have substituted ferrous, wood and ceramic materials in many applicationsfor which reason, polythene consumption has increased exponentially in the past decades. Until recentlypolythene waste were disposed to landfills after their use. This disposal creates environmental pollution andspace problem because they are not biodegradable easily on like other materials.To resolve environmental pollution caused by polythene waste in Nigeria we have to adopt a new managementof discarding process (i.e. re-cycling them) instead of throwing them into the land as landfills. The land getlittered by polythene bags garbage presenting an ugly and unhygienic seen. They find their way into the city anddrainage system resulting to blockage case in convenience, difficult to maintaining the drainage with increasedcost.Recycling consists in processing post consumer materials to produce raw materials for new products. It can bewidely used and will help to increase plastic recovering percent because increasing knowledge about propertychange will increase the demand for recycling of the polythene material.The environmental control of polythene waste by recycling method will help in transforming the waste intoreususable products thereby reducing the quantity of waste in Nigeria environment.The reuse of this waste polythene products such as the conversion from sachet water bags into candle productshas been reported by (Edoga eta 2007) and other reuse product such as fuel oil (Jalil, 2002). according to theWikipedia 2009, the application of bacteria can degrade over 40% of the weight of plastic bags in less thanthree months.The objectives of this research are to enlighten people on the level of pollution caused by polythene pollutants inNigerian environment particularly in the residential and some commercial and institutional centres, to identifythe potential sources of these environmental potentials in Nigerian environment and to draw appropriateconclusions and make recommendations to solve the problem of polythene pollution in Nigeria.31

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011This work will help to assess the levels of pollution caused by polythene waste which produces poisonous gas tothe environment (land, water and air) when burnt, for example carbon monoxide (Co) is introduced into theatmosphere as a result of polythene burning. It will also see polythene waste not only as a pollutant but also as araw material for the production of plastic and insulation cable for electrical equipments and vehicle parts.Polythene materials are those materials made from a chemical compound known as polyethylene (C-H) n and ismanufactured from the polymerization of ethylene (C-H) as represented in Figure 1. Basically, polyethylene isan odorless, translucent solid, commercially available in pellet form which is convertible to derivative productssuch as the polythene bags. Pep is stable and inert polymers, exhibiting very high resistance to chemical attack.HHHHFigure 1: Polyethylene structurePOLLUTION CAUSED BY POLYTHENE WASTEEnvironmental pollution created by polythene includes soil, water and air contamination and blocking of drainsand sewage lines in and around cities. Since polythene is non-degradable, it remains intact in water and soil formany years; and are not productive to the soil as reported by Aziegbe (2007) and federal environmentalprotection agency (FEPA) (1998) and Luwig (1990) and Ibanga (2000) Sharma and Kanwar 2007). Adverseeffects on livestock have also been reported (Mohammed and Muhammed 2007). Open burning of refuse dumpsin developing countries is a common practice (Izugbara and Umoh 2004). It has been realized that if burnedpolythene products, it produce harmful toxins which can threaten air quality (UNEP 2002; Sharma and Kanwar2007). Some of the toxic substances release include pops such as hazardous dioxins (UNEP 2002) otherthermal/oxidative degradation products of the polythene in controlled condition have been studied and consistsof chemical that are harmful to human health and area of environmental concern (Sojak etal, 2006).The environmental pollutants are those materials that cause pollution to our environment, which may beclassified as air, water or land pollutants which polythene belong. These pollutants may be degradable or nondegradableand can be found in drainages. They introduce contaminants into the environment that causesinstability, disorder, harm or discomfort to the ecosystem. They also cause delayed flowering in plants, sciencedaily .CLASSIFICATION OF POLYTHENEPolythene material is classified into several different categories based mostly on its density and branching. Themechanical properties of polythene depend significantly on variables such as the extent and type of branching,the crystal structure and the molecular weight, with regard to solid volumes, the most important polythenegrades are HDPE, LLDPE and LDPE (Wikipedia, 2009).The surface of the earth where man spends his entire life has undergone drastic changes arising from main’sintervention in many natural processes. Polythene waste is the unwanted discarded over used polythene productsand they remain as waste in the environment. They constitute the acids, chemicals, oils and grease, total32

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011suspended solids, total dissolve solids, heavy metals ions, mercaptans, packaging materials, polyolefins,polystyrene for packaging electronic materials, radio and television sets.Of all classes of wastes, polythene waste posses the greatest threat to life, because it has the potential ofpolluting land, water and air using water and air as transport media. Air pollution is one of the manyenvironmental problems posed to man from his surroundings. It is the presence of substances or contaminants inthe outdoor atmosphere in concentration large enough to be injurious to human, plants and animal life. Airpollution is caused by both natural and artificial means of introducing gasses or particulate substances(contaminants) into the atmosphere. The composition of air reveals some of the pollutants in the atmosphere.Polythene waste affects the environment by degradation to produce poisonous gases which is harmful to theenvironment. For example PVC can degrade to Hcl gas which is poisonous and when in contact with flame incase of bush burning can produce gas which is poisonous to man (Aziegbe, F. I., 2007).Water is very essential to plant and animal lives. It is being polluted as a result of the introduction of polythenewaste in form of gases, liquid (sludge) and solid into a body of water which affects both the surface andunderground water. Polythene waste destabilizes the characteristics of water and affects its temperature, taste,odour, colour, turbidity, amount of suspended solids (ss), and electrical conductivity of water. It has also beenobserved that fish and other marine species in the water ways misunderstanding polythene material as fooditems, swallow them and die (West, 2006).Lands are being polluted as a result of indiscriminate dumping of polythene waste. Many materialsmanufactured from polythene, example slippers, plastic shoes, chairs, toys are discarded when they are spoiledand this constitutes polythene waste. These polythene wastes apart from reducing the aesthetic value of land canalso degrade to produce simple chemicals which may be poisonous and harmful to health, thus the damage doneto the environment by polythene waste can be reduced through minimization of waste production, suitablemeans of waste disposal, recovery, conversion, control and reuse (Olanrewaju and Ilemobade, 2009).EFFECT OF POLYTHENE WASTE ON ENGINEERING SOILDuring construction of houses or drainages there is a necessary demand for the excavation of the entire areaneeded for sub-structure (foundation), in the case of road construction cutting of the vegetable soil which is nota good engineering soil is required. In this study it was found that during this excavation the area wherepolythene waste are buried long before the job is to be done tends to pose more difficulty in excavation becauseof its chemical constituents present in the polythene material which hardens the soil when decomposed.Polythene waste does not allow for a complete compaction and consolidation of the soil which then reduces thebearing and shearing strength of that particular soil according to (Awomeso, and Taiwo, (2010). EnvironmentalScience Publications, 2010 and (Sybil 1997)RESEARCH METHODOLOGYMATERIALS RECOVERYTwo major approaches were adopted in acquiring the data used for this study. A daily market namely; AkpanAndem market was selected for data collection. Two areas measuring 10 meters by 30 meters were demarcatedin such a manner that one was the raw food section and the other in the processed food items (provision stores)section. In the market one of the sanitation personnel was made to sweep the demarcated areas daily and wasinstructed to always select the cellophane from other wastes. These were stored in special refuse collection binsand were measured weekly. And because it is also within the scope of this study to determine and compare theamount of cellophane generated at homes and in the market, 100 waste paper baskets were distributed to 50respondents approached previously to participate in this study. Each participant was given two waste paperbaskets, while one of these baskets was to be placed and monitored in the market, the other is to be used athomes. Data were collected on weekly basis in the month of July and November 2010. The data were analyzedusing percentage and bar charts. However this study concentrated only in the market and at homes because theseareas are the major generating and disposal points.33

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011Methods of Recycling PolytheneThe following procedures of recycling polythene materials were adopted;(i) Inspection – polythene wastes are inspected for contaminants such as rock and glass and for materialsthat the plant cannot recycle.(ii) Chopping and washing – the polythene wastes are washed and chopped into flakes using the washingmachine as shown in Figure 1.Fig. 1: Washing Machine(iii)Flotation tank – If mixed polythene are being recycled, they are sorted in flotation tank, where sometypes of polythene sink and other float. The floatation units are shown in Figure 2a and Fig 2brespectively.Fig. 2(a) Floatation Unit Fig. 2 (b) Floatation Unit(iv)Drying – The polythene flakes are then dried in a tumble drier as in Figure3.34

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011Fig. 3: Drying Machine(v)Melting – The dried flakes are fed into an extruder where heat and pressure melt the polythene. Theextruding machine is shown in Figure 4. Different types of plastic melt at different temperatures.Fig. 4: Extruding Machine(vi)(vii)Filtering – The molten polythene is forced through a fine screen to remove any contaminants thatslipped through the washing process. The molten plastic is then formed into strands.Pelletizing – The strands are then cooled in water, using the cooling bay as in Figure 5, then they arechopped into uniform pellets using the palletizing machine shown in Figure 6a, and the manufacturingcompanies buy the plastic pellet from recyclers to make new products as in Figure 6b.35

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011Fig. 5: Cooling BayFig. 6 (a): Pelletizing MachineFig. 6 (b): Pelletized ProductRESULTS AND DISCUSSIONThe polyethylene collected were sorted and counted. The result shows that table water sachet topped the list,following that order of descending magnitude is ice cream and biscuit wrapper (Table 2). Table water sachettopped the list because; it is consumed throughout the year with a very little seasonal variation, Again, thestudied markets have no public portable water system where the traders can get their drinking water. As a result,majority of them depend on the sachet water on a daily basis. Some traders who take their drinking water to themarket from home soon discover that the water becomes too worm and unfit for consumption in the afternoonsparticularly on dry season.Consequently, they resort to the cold sachet water that is being hawked all over the market. Ice cream wrappersexhibited the highest variation in this study. Their generation and disposal are readily compared both during thedry months and the heart of the wet season. Polyethylene for assorted items also exhibited high seasonalvariation. This implies that its demand and consumption is almost uniform throughout the year. Arup etal,(2006) reported similar finding for Ibadan. She noted that among the non-biodegradable solid waste generated,cellophane is mostly affected by seasonality. Types of cellophane generation at home and market also displayeda very interesting pattern (Table 1a and 1b).Table 1a: Show polyethene generated at Homes and Market during dry season month of November 2010Place / Types Assorted Biscuit wrappers Ice cream Pure water sachetsachetsMarket (kg)/week 28,050 33,475 44,859 52,998%dry at the market 9.9 11.55 15.4 18.15Homes (kg)/week 54,099 24,895 19,533 13,948% dry at homes 26.96 12.1 9.35 6.636

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011Fig. 7a: Bar Chart showing polyethene waste generated at homes and market during dry season month, Nov.2010.Table 1b: Show polythene generated at homes and market during wet season month of July, 2010Place / Types Assorted Biscuit wrappers Ice cream sachets Pure water sachetMarket (kg)/week 22,950 27,388 36,703 43,362% wet at the market 8.1 9.45 12.6 14.85Homes (kg)/week 44,262 20,368 15,981 11.412% wet at homes 22.05 9.9 7.65 5.4Fig. 7b:Bar Chart showing polyethene waste generated at homes and market during wet seasonmonth, July 2010In ascending order, it shows that polyethylene for assort items was the least (51,000 kg), followed by biscuit(56,865kg), ice cream sachets (81,526kg) and table water sachets (96,361kg) in the market. At home, the trenddisplayed, when arranged in closely followed by biscuit wrapper (45,263kg), ice cream wrappers (35,514kg)and table water sachets (25,360kg). Cellophane for assorted items ranked lowest in the market because they areused in wrapping items in the market but disposed off at home having removed the contained items for cookingor storage. The generation of table water sachet was lowest at home but highest in the market. This is so becausemost homes have refrigerator where they can store water for it to get cool/cold.The findings is in agreement with Ibanga (2000) study in Yola, Northern Nigeria, where he reported that coolsachet water and ice cream are sold more at markets and schools. The mean number of individual polyethylenegenerated was also examined.37

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 20112).Further analysis showed that an individual generated and disposed 0.665kg of cellophane daily (TableTable 2: Measured and estimated amount of polyethylene generated by individual in Uyo, Akwa Ibom State andNigeriaCategory Estimated population (m) No. of polyethylene/weekIndividual Individual 0.665kgTotal for Uyo 1.2 million 1.4 millionTotal for Akwa Ibom State 3.92 million 2.53 millionNigeria 140 million 9.31 millionMeasured Estimated Source: Field work 2010Using this individual mean, estimate, one can begin to imaging the number of volume of cellophane beinggenerated and disposed in Nigeria in its environmental context. The questionnaire survey further reveals that82% of the respondents prefer the use of polyethylene as wrappers and natural leaves because they are cheaper.Some 80% prefer polyethylene wrapper because they are relatively cheaper with higher aesthetic value. Only15% showed preference for local leaves as wrappers and these were mainly the aged ones. Fig. 7a is a bar chartsshowing polythen waste generated at homes and market during dry season, while fig. 7b also gives the bar chartshowing the polythene waste generated at home and market during the wet season. From the chart it’s shownthat more waste are generated in wet season.RECYCLED POLYETHYLENEFor this to be achieved, generated waste materials passes through several processes which are earlier mentionedin the course of this work. A black rough pellet of plastic by-product is achieved at the end of this experiment(Fig. 6b) and this product is used to produce a new poly-bags of either HDPE, MDPE or LDPE is producedusing these pellets.• HDPE-High density polyethylene as in fiqure8 is defined by a density of greater or equal to 0.941g/cm 3 . Ithas a low degree of branching and thus stronger intermolecular forces and tensile strength. It is used inproducts and packaging such as milk jugs, detergent bottles, margarine tubes, garbage containers and waterpipes.Fig. 8: High Density Polyethylene (HDPE)• MDPE – Medium Density Polyethylene is defined by a density of 0.926 – 0.940g/cm 3 . It can bychromium/silica catalysts. It has a good shock and drop resistance properties and is also less notch sensitivethan HDPE. It is used for the production of gas pipes and fitting sacks, shrink film, packaging film, carrierbags and screw closures. These classes of polyethylene materials are less dense than the HDFE, and arereferred to as MDFE as in figure 9.• LDPE – Low Density Polyethylene is defined by a density range of 0.910 – 0.940g/cm 3 . It has a highdegree of short and long chain branching which means that the chains do not pack into the crystal strong aswell. It has less strong intermolecular forces as the instantaneous – dipole induced-dipole attraction is less.38

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011• This result in a lower tensile strength and increased ductility. LDPE is created by free radicalpolymerization. It is used for both rigid containers and plastic film application such as plastic bags and filmwrap.Fig. 9: Low Density Polyethylene (LDPE)• MASTER BATCH POLYETHYLENE: This is a coloured polyethylene in pellet form. It is use for thedetermination of a particular colour of a poly-bag at the ratio of 1:25 and its density is 0.940g/cm 3 . Whenthe density is lighter than the MDFE, the products are useful for the production of polybags such as theblack master batch and the blue master batch as presented in fiq.10a and 10b, while fiq.11 represent therecycled products.Fig. 10(a): Black Master BatchFig. 10(b): Blue Master BatchFig. 11: Recycled Product39

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011DISCUSSIONTechnological advances continued during the first half of the 20 th century, including the development of garbagegrinders, compaction trucks and pneumatic collection systems. By mid-century, however, it had become evidentthat open dumping and improper incineration of polyethylene waste were causing problems of pollution andpublic health. As a result, sanitary landfills were developed to replace the practice of open dumping and toreduce the reliance on polyethylene waste incineration. New refuse incinerators of polyethylene were designedto recover heat energy from the waste and were provided with extensive air-pollution controls devices to satisfystringent standards of air quality.SUMMARYThe study was carried out to investigate the environmental pollutant caused by polyethylene materials inNigeria. Relevant literature such as classification of polyethylene, effects of polyethylene waste on theenvironment; effect of polyethylene waste on engineering soil, methods of polyethylene treatment andpolyethylene waste as a toxic pollutant were reviewed.This research work was based on the generation of polyethylene materials, it recycling into a by-product for theproduction of a new polyethylene product.CONCLUSIONPolyethylene waste generation was found to be higher during the dry season months (November – March) thanthe wet season months (April – October) with the least in the month of June. None foodstuff markets dominatedby male traders who depend solely on wrapped food items with polyethylene had the highest cellophanegeneration. Cellophane generation was also higher in the markets than at homes. This is so because at homes,most food is served with plates and the consumption of table water and ice cream are considerably reduced. Alarger proportion of the respondents prefer the use of polyethylene as wrappers, to newspaper and local naturalleaves because of its cheapness, neatness and readily availability. Generally, respondents use polyethylene forshopping.Polyethylene is a major source of environmental degradation in Nigeria, and this form of environmental abuse isworst in the urban areas.For a cleaner and sustainable environment therefore, massive awareness campaign and enlightenment about thedanger cellophane poses to our environment should be vigorously carried out. Government should providepublic waste bins mainly for polyethylene materials in strategic positions for the collection of this waste.The ministry of environment should employ more personnel. The government and individuals should considerrecycling option of polyethylene material as the best option of treating its waste.REFERENCESArup, C. Mandira, M. J. and Basudam, A. (2006). Indian Journal of Chemical Technology, Vol. 13.Aziegbe, F. I. (2007). Seasonality and Environmental Impact Status of Polyethylene in Benin City: NigeriaJournal of Human Ecology 22(2) 141 – 147.Federal Environmental Protection Agency (FEPA) (1998). Industrial Pollution, Policy and Management Study.A World Bank- funded Project, Geomatics Nigeria Limited, Nigeria.Green Living Tips, (2009). Waste decomposition rates, www.greenlivingtips..com/articles/311/1/wastedecomposition-rates.html.Ibanga, F. M. (2000). Polymer Waste Treatment of Effluents and Sediments from Plastic Company.Unpublished Research Project, Department of Chemistry, Uniuyo.Izugbara, C. O. and Umoh, J. O. (2004). Indigenous Waste Management Practices among the Ngwa SouthEastern Nigeria: The Environmentalist 24(2): 87-92.Awomeso, J.A. and Taiwa (2010). Environmental Science Publication.40

Ukpong, E. C and Peter, Chamberlain M Continental J. Water, Air and Soil Pollution 2 (1): 31 – 41, 2011Jalil, P. A. (2002). Investigation on Polyethylene Degradation into fuel oil over Tungs to Phosphoric Acidsupported on Mesoporous Silica, Journal of Analytical and Applied Pyrolysis. 65:185-195.Luwig, H. F. (1990). Moving Towards Economic and Environmental Sustaining in Asian Developing Countries.The Environmentalist. 10(4), 2, 37 – 80.Mohammed, A. K. and Muhammed, I. R. (2007). Fata Polyethene Bag Rumen Implication in Cattle at Shika-Zaria Nigeria: Research Journal of Animal Science.Mumine, S. P. and Sanche, R. A. (1992). New Directors in Marian Environmental Policy. EnvironmentalManagement. 16(4) 4465 – 74.Olanrewaju, O. O. and A. A. Ilemobade, (2009). Waste to Wealth: A Case Study of the Ondo State IntegratedWaste Recycling and Treatment Project: Nigerian European Journal of Social Sciences.Sharma, N. and Kanwar, P. (2007). Perception of Rural and Urban Homemakers Regarding Ban on Polythenein the State of Himachai.Sojaka, L., Kubineca, R., Jurdaovaa, H., Hajekovab, E. and Bajusb, M. (2006). GC – MS of Polyethylene andPolypropylene Thermal Cracking Products Petroleum & Coal 48(1): 1 – 14.Sybil, P. P. (1997). Air Pollution. McGraw-Hill Encyclopedia of Science and Technology, Vol. 1. 8th Edition:New York, pp. 280 – 298.United Nation Environmental Programme (2002). Regionally Based Assessment of Persistent Toxic ChemicalsSub-Saharan Report. GEF UNEP. Stockholm, Sweden.of Germany.West, L. (2006). World Water Day. Wikipedia, the Free Encyclopedia.Wikipedia (2009). Polyethylene, Online free Encyclopedia, Wikimedia Foundation Inc. USA.http://www.wikipedia.orgReceived for Publication: 30/06/11Accepted for Publication: 01/07/11Corresponding AuthorUkpong, E. CCivil Engineering Department, University of Uyo, Uyo, Akwa Ibom State, Nigeria41