School of Egineering and Engineering Technology
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Item Open Access Model for evaluating the concentration of Iion upgraded during pyrobeneficiation of Iron oxide ore pelletized with powdered potassium Chlorate(U. P., 2009) Nwoye, Chukwuka Ikechukwu; Obiji, Stephen; Anyika, Livinus; Nwoye, Uchenna Chukwuma; Obi, Marthins; Uzoije, Atulegwu Patrick; Ofoegbu, Stanley UdochukwuModel for predicting the concentration of iron upgraded during pyrobeneficiation of iron oxide ore (pelletized with powdered potassium chlorate) has been derived. The model-predicted %Fe upgrades were found to agree a direct relationship between %Fe values and weight-input of KClO3 as exhibited by %Fe upgrades obtained from the experiment. The model; %Fe = 7.1367γ indicates that iron upgrade is dependent on the weight input of KClO3. The validity of the model was rooted in the expression (%Fe/γ)α = (T/β)N where both sides of the expression are correspondingly almost equal. The positive or negative deviation of each of the model-predicted values of %Fe from those of the corresponding experimental values was found to be less than 19% which is quite within the range of acceptable deviation limit of experimental results.Item Open Access Model for calculating the quantity of heat absorbed by oxalic acid solution relative to the final solution pH during leaching of iron oxide Ore(U. P., 2009-09) Nwoye, C. I.; Mbuka, I. E.; Nwoye ,C. C.; Obi, M. C.; Uzoije, A. P.Model for calculating the quantity of heat absorbed by oxalic acid solution during leaching of iron oxide ore has been derived. It was observed that the validity of the model is rooted on the expression InQ = γN where both sides of the expression are approximately equal to 7. The model was found to depend on the value of the final solution pH measured during the experiment. The maximum deviation of the model predicted Q values from the corresponding experimental values was found to be less than 11% which is quite within the acceptable range of deviation limit of experimental results. The positive values of heat absorbed as obtained from experiment and model agree and show that the leaching process is endothermic in nature.Item Open Access Correlates of cardiorespiratory fitness and gait parameters in young undergraduate subjects(U. P., 2010) Azeez, T. O.; Lamina, S.; Iwuji, S. C.Physiological studies of healthy individuals suggested that the pattern of walking influenced the oxygen cost of walking in a given distance. It has also been observed that in pathological states, shorter and frequent steps are common and that this inefficient gait might contribute to exercise limitation. The purpose of the present study was therefore to investigate the corelates of cardiovascular fitness and gait parameters in young undergraduate students. A cross sectional independent group design was used in data collection. Forty subjects with age ranged between 20 and 30 years participated in the study. Subjects’ cardiorespiratory fitness was assessed using the 1.4 miles run; subjects were group into cardiorespiratory fitness category of high and low. Gait parameters (cadence [CD], step time [ST] & gait speed [GS]) were assessed using the paper-and-pencil method. Student t test and Pearson correlation test were used in data analysis. Findings indicates significant increase in the high fit group over low fit group in CD, ST and GS at p<.05. There was a significant positive and negative correlation between VO2max and gait variables respectively: GS (.465), CD (.555) and ST (-.580) at p<.01. The present study concluded that cardiovascular fitness could be a positive factor/marker of qualitative pattern of walking in normal young adult. Future studies investigating the effect of physical training on pattern of walking in the healthy, chronic diseases and the disables are recommended.Item Open Access Ergogenic controversies of socio-cultural African herbs: A review study on khat (CATHA EDULIS) and kolanut (Cola Spp)(U. P., 2010) Lamina, S.; Azeez, T. O.; Subramanian, M.; Ayana, A. M.Khat and kola nut, are highly controversial ergogenic herbs indigenous to Africa and in the countries around the Red Sea. The spectrum of khat actions has been postulated to lie between amphetamines and caffeine while kola nut active chemical is caffeine. Therefore, khat and kola nuts and their principal active constituents (cathinone, cathine and caffeine respectively) are categorized as stimulants. The chewing of khat leaves and kola nuts has a deep rooted religious and socio- cultural tradition in Africa. Ironically, the World Antidoping Agency and the International Olympic Committee have placed a limit to cathine usage in sports. Caffeine, though not presently in the list of banned substances, but was previously banned, unbanned and restricted before 2004. Reasons for the partial ban and unban of cathine and caffeine respectively seem unclear and ambiguous. It is also confusing and worrisome if, the ethical line of cheating in sport is being scrutinized more carefully, or weather a cultural incident of khat and kola nut chewing is being handled appropriately. Before a conclusive statement could be made on the ergogenic status of both herbs, there is a need for joint extensive studies and international conference of stakeholders.Item Open Access Exercise and pregnancy: A review study(U. P., 2010) Lamina, S.; Musa, D. I.; Hanif, S.; Azeez, T. O.In recent times, researchers, exercise advocates and other professional experts in women’s health are agitating for women participation in exercise programme. Reasons for this advocacy might not be unconnected to the fact that the benefits of exercise for women far outweigh the complications particularly in pregnancy. This paper review significance of exercises during pregnancy. The review revealed that it is unrealistic for pregnant women to participate in vigorous physical activity, but could benefit from antenatal physiotherapy. It is also apparent that female athletes tend to have fever pregnancy and child birth related complications than do normal non athletic women. This is suggestive that women should be physically active but pregnant women continue to participate in activities which they are familiar with, while regular participation of women of reproductive age in exercise and sports is highly encouraged.Item Open Access Distribution of cyanide in a cassava-mill-effluent polluted eutric tropofluvent soils of Ohaji Area, South-eastern Nigeria(Academic Journals, 2011) Uzoije Atulegwu Patrick; Nnamdi Egwuonwn; Onunkwo-A, AugustineThis study investigates on the distribution of cyanide on a cassava- mill- effluent polluted eutric tropofluvent soil in Ohaji southern Nigeria. Three morphological land units were marked out namely, the background unit (pedon A), discharged point unit (pedon B) (the effluent receiving unit) and downstream unit (pedon C). Soil sample collection was carried out in five replicates in May 2007 adopting a randomized complete block design techniques. Soil samples were collected from each pedon at different soil profiles: 10 to15, 15 to 30, 30 to 70, 70 to 100 and 100 to 150 cm which were represented as L1, L2, L3, L4 and L5, respectively. Samples of the cassava mill effluent were also collected in five replicates. Standard laboratory methods were adopted for the analysis of both samples. It was observed from the results that cyanide distributed geospatially within the pedons. Furthermore, the results of the soil samples were subjected to correlation and regression analysis between Cn and other soil properties and the analysis showed highly positive significant variation(p = 0.05) in Na, Cd, pH, and clay in both pedons A and B while Pb, sand silt and porosity showed highly negative significance in both pedons. Most soil properties showed non significance in pedon C. Highcoefficients of regression for polynomial functions were recorded in most pedons.Item Open Access Kinetics of degradation of anthracene by the activity of corynebacteria sp and pseudomonas putida in contaminated water(Bio IT Journals, 2012) Azeez, Taofik Oladimeji; Owabor, C. Ngozi; Nwacha, RichardThe environmental threat of anthracene to humans on exposure through industrial effluent discharged and other combustion activities into the environment with expensive nature of the physical and chemical remediation techniques initiates this research. The kinetics of degradation of anthracene by the activity of Corynebacterium sp and Pseudomonas putida for the liberation of the anthracene contaminated water was aim to be investigated. The enriched inoculums of Corynebacterium sp and Pseudomonas putida was separately inoculated into anthracene contaminated water at room temperature of 280C under an optimum pH of 7.2 for 96hours, thereby decreased the anthracene content in the water. About 95.2% of anthracene was degraded by Corynebacterium sp while about 93.5w/w% of anthracene was degraded by Pseudomonas putida. The biodegradation kinetics parameter evaluated indicates that both Corynebacterium sp and Pseudomonas putida were favourable for bioremediation of anthracene contaminated water but Corynebacterium sp was preferred due to higher proportion of anthracene utilized.Item Open Access Activated orange meso-carp carbon (AOMC); an acceptable remediation techniques for crude oil pollution effect(Maxwell Scientific Organization, 2012-01-01) Atulegwu, Patrick Uzoije; Uzoigwe, Luke O.; Kamalu , C. I. O.Orange mesocarp with its potentials application to remove spilled crude oil was used to prepare an activated adsorbent. Therefore, adsorption of crude oil onto the activated orange meso-carp (AOMC) was investigated. Batch experiment was adopted for the equilibrium studies and the studies were conducted for various operational parameters such as varying crude oil concentration and temperature values. The crude oil samples of A, B, C, D and E, with concentrations 6045, 4393, 8508, 11583, and 5220, respectively and temperature values varied between 10-50ºC were used for the experiment. The adsorption equilibrium was established at 40 min of adsorption time. Partition coefficients, kd (L/kg) for various samples reacted inversely with temperature and were in the ranges of 0.37-0.69, 0.65-1.11, 1.28-2.04, 1.17-1.39 and 1.23-4.53 for samples A, B, C, D and E, respectively. percentage of crude oil samples on the AOMC decreased with low crude oil hydrocarbons and the trend was shown as follows D>C >A>E>B. Percentage ranges for samples A, B, C,D and E were given to be 86.8-88%, 60.5-72.4, 52.5-55.2, 47.9-55.4 and 45.3-49.2%, respectively. Sorption of the crude oil samples to AOMC was found to be spontaneous, exothermic, and physio-sorption controlled with G values being in the ranges of -71.49 to -21.29, -18.25 to -5.43, -30.24 to -21.11, -28.55 to -11.33 and -50.74 to -50.12 KJ/mol for samples A ,B , C , D and E, respectively. Enthalpy(H) and Entropy changes(S) were also found to be -10.28, -12.24, -8.92, -6.9, -50.28 J/mol/K and -2.92, -0.32, -0.50, -0.44, -0.01 for samples A, B, C, D and E, respectively. Activated orange meso-carp provides a veritable environmentally remediation technique for crude oil spillage.Item Open Access Evaluation of the effects of industrial wastewater discharge on surface water (A case study of Nigeria Breweries Plc Enugu)(U. P., 2012-09) Egwuonwu, C. C.; Uzoije, A. P.; Okafor, V. C.; Ezeanya, N. C.; Nwachukwu, M. U.The need to undertake an evaluative effect of industrial wastewater discharge on surface water with a case study of Nigerian Breweries Plc Enugu into the Ajali River was borne out of the need to ascertain the level of Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total suspended Solids (TSS) etc and other characterized effluent been discharged into the water body that determines the level of use and quality of this water for irrigation purposes, human consumption and safe ecological habitation of aquatic lives. To achieve this, laboratory analysis was carried out on the Ajali River and the wastewater discharged from the industry and it was confirmed not to have exceeded the benchmark for required discharge of wastewater into streams and rivers as stipulated by some regulatory bodies. In conclusion, treatment measures and regulatory policies were suggested to checkmate the abuse of this water bodies and the danger it might likely pose to aquatic ecological system if regulatory standards were not complied with.Item Open Access Evaluation of the effects of industrial wastewater discharge on surface water (A case study of Nigeria breweries Plc Enugu)(U. P., 2012-09) Egwuonwu, C. C.; Uzoije, A. P.; Okafor, V. C.; Ezeanya, N. C.; Nwachukwu, M. U.The need to undertake an evaluative effect of industrial wastewater discharge on surface water with a case study of Nigerian Breweries Plc Enugu into the Ajali River was borne out of the need to ascertain the level of Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total suspended Solids (TSS) etc and other characterized effluent been discharged into the water body that determines the level of use and quality of this water for irrigation purposes, human consumption and safe ecological habitation of aquatic lives. To achieve this, laboratory analysis was carried out on the Ajali River and the wastewater discharged from the industry and it was confirmed not to have exceeded the benchmark for required discharge of wastewater into streams and rivers as stipulated by some regulatory bodies. In conclusion, treatment measures and regulatory policies were suggested to checkmate the abuse of this water bodies and the danger it might likely pose to aquatic ecological system if regulatory standards were not complied with.Item Open Access Optimization of bioremediation of cheese whey with the activity of klebsiella pneumonia using response surface methodology(U. P., 2013) Azeez, T. O.; Onukwuli, O. D.; Araromi, D. O.; Arinkoola, A. O.; Salam, K. K.; Iwuji, S. C.; Ejeta, K. O.; Dawodu, B. F.; Ayinde, K. A.; Nwacha, R.; Azeez, F. O.Response surface methodology was used to study the optimization of bioconversion of cheese whey to 2,3-Butanediol using Klebsiella pneumonia at room temperature. 3-Level factorial design was employed to correlate the bioremediation parameters with the biomass of K. pneumonia and concentration of 2,3-BD as response. Quadratic polynomial equation was developed to achieve optimal performance of the process. The result showed that the optimum condition for the bioremediation process in unaerated and airlifted batch reactors for concentration of cheese was 39.98g/L and 39.94g/L, and fermentation time was 95.5hours which resulted in biomass of k. pneumonia 1.4633mg/L and 3.6580mg/L, and 2,3-BD production of 10.696g/L and 17.997g/L respectively. 2,3-BD production in unaerated and airlifted batch reactors amounted to 36.88% and 62.06% respectively. The study has shown that k. pneumonia not only utilized cheese whey as a source of food and energy but optimally better for remediation of cheese whey in airlift batch reactors.Item Open Access Nutritional evaluation of medicinal cnidoscolus aconitifolius (Chaya) leaves used in Nigeria(ABC Publishers Inc., 2013) Iwuji, S.; Nwafor, A.; Azeez, T. O.; Nwosu, E. C.; Egwurugwu, J.; Danladi, N. B.Evaluation of the nutritional content of edible plants is currently essential for safety. This work assessed the proximate and mineral composition of the leaves of Chaya plant (Cnidoscolus aconitifolius) commonly known as ‘hospital is too far’ and consumed in Niger Delta, Nigeria for medicinal and nutritional purposes. The study showed that the dried leaves of the plant contain 47.03 ±1.02% of nitrogen free extract; 33.04± 3.14% of crude fibre; 7.03±0.23% of crude fat; 4.03±0.67% of crude protein, while moisture and ash made up 6.10±1.10% and 3.04±0.32%, respectively. A gram of the dried leaves yielded (in mg) 10±1.2, 20±1.6, 0.01±0.1, 100±5.3, 85±4.32, 18±2.1 and 50±2.3 of Iron, Phosphorus, Sodium, Potassium, Magnesium, Manganese and Calcium, respectively. The energy yield was 258±4.5kcal/100 mg. These results suggested the comparative richness of the leaves in fibre, high nitrogen free extract (carbohydrate) and essential minerals to prevent nutritional and electrolyte deficiency disorders among the consumers.Item Open Access Nutritional and electrolyte values of cnidoscolus aconitifolius (Chaya) leaves consumed in Niger Delta, Nigeria(U. P., 2013) Iwuji, Samuel Chidi; Nwafor, Arthur; Azeez, Taofik Oladimeji; Nwosu, Emmanuel Chibuike; Nwaokoro, Joakin Chidozie; Egwurugwu, Jude; Danladi, Nygan BalaEvaluation of the nutritive and electrolyte values of edible plants is currently essential for human nutrition and safety. This work assessed the proximate and mineral composition of the leaves of Chaya plant (Cnidoscolus aconitifolius) consumed in Niger Delta Nigeria for medicinal and nutritional purposes. Chaya is commonly known in this southern area of Nigeria as ‘hospital is too far’ or ‘ogwu obala’. The study showed that the dried leaves of the plant contain 47.03 ±1.02% of nitrogen free extract; 33.04± 3.14% of crude fibre; 7.03±0.23% of crude fat; 4.03±0.67% of crude protein, while moisture and ash made up 6.10±1.10% and 3.04±0.32%, respectively. A gram of the dried leaves yielded (in mg) 10±1.2, 20±1.6, 0.01±0.1, 100±5.3, 85±4.32, 18±2.1 and 50±2.3 of Iron, Phosphorus, Sodium, Potassium, Magnesium, Manganese and Calcium, respectively. The energy yield of the leaves was 258±4.5kcal/100 mg. These results suggested the comparative richness of the leaves in fibre, high nitrogen free extract (carbohydrate) and essential minerals. Properly prepared leaves are therefore recommended for daily consumption in order to supplement the recommended daily intake of nutrients and minerals and hence prevent nutritional and electrolyte deficiency disorders.Item Open Access Effects of antioxidants on the oxidative stability of vegetable oil at elevated temperature(Center for Promoting Ideas, USA, 2013-05) Azeez, Oladimeji T.; Ejeta, Kennedy O.; Ehigiator, O. Frank; Nwakamma, E. GeraldUnstable nature of vegetable oil posed serious health risk to humans. The oxidative stability of vegetable oils (Palm Olein, Soyabean Oil and Linseed Oil) with direct incorporation of antioxidants (tertiary butyl hydroxoquinone (TBHQ), butylated hydroxyl toluene (BHT) and mixed (TBHQ and BHT) at room temperature and 700C for 168 hours was aimed to be investigated. Peroxide value was determined and the oxidative stability was evaluated. TBHQ had significant effect on the oxidative stability of palm olein at 700C while (TBHQ and BHT) had synergetic effect on stability of Soya bean oil at room temperature and Linseed oil at 700C.Item Open Access Effect of mahogany filler on mechanical properties of reinforced polyethylene matrix(SAVAP International, 2013-07) Olaitan, S. A.; Azeez, T. O.; Atuanya, C. U.; Onukwuli, O. D.; Officha, M. C.; Menkiti, M. C.The effect of mahogany filler as an agricultural waste material used in thermoplastic polymer composite was investigated. Polyethylene (PE), as the matrix, and mahogany sawdust, as the filler, were prepared in five levels of filler loading (10, 20, 25, 30, and 35 wt %) to form thermoplastic composites.Two forms of composite samples were prepared with a recycled polyethylene and mahogany wood filler called recycled polyethylene (RPE) composite and 20 percent of virgin polyethylene with recycled polyethylene wood filler called virgin polyethylene recycled polyethylene (VRPE)composite and their mechanical properties were studied. Test results show that the tensile strengths, tensile modulus, flexural strengths, flexural modulus and hardness properties increased while impact strength, decreased with increase in filler loading for the mixed polyethylene composites but tensile strength of there cycled polyethylene composite decreased with increased filler loading. The appreciable improvement on the tensile strength indicates that mahogany can be used as a reinforced material of the mixed polyethylene composite. Again the presence of 20 percent of virgin PE has significant effects (p < 0.05) on mechanical properties of the mahogany filler – recycled polyethylene composite.Item Open Access Effect of rice husk filler on mechanical properties of polyethylene matrix composite(2013-08) Atuanya, C. U.; Olaitan, S. A.; Azeez, T. O.; Akagu, C. C.; Onukwuli, D. O.; Menkiti, M. C.compositeIn the present work, the effect of rice husk filler loading (10%, 20%, 25%, 30%, and 35%) on the mechanical properties of recycled low density polyethylene (RPE) and mixed with 20 percent weight fraction of virgin polyethylene (MPE) composites was aimed to be investigated. The waste polyethylene was blended with virgin polyethylene and the composites of RPE and MPE were moulded with the addition of rice husk filler using injection moulding machine at a pressure 150MPa and temperature 160oC. The composites were cut into specified dimensions and mechanical properties were conducted on them. Tensile strength increased up to 10 percent weight fraction of rice husk filler in the composites and later decreased above 10 percent filler loading. Tensile modulus, flexural strength and modulus, and Brinell hardness increases with increased filler loading, but impact strength decreases with increased in filler loading. The rice husk filler loading had significant effect (p < 0.05) on the mechanical properties of MPE composite compared with RPE composite which indicated that rice husk filler may be used for reinforcement of PolyethyleneItem Open Access Diffusivity and kinetics model for biodegradation of PAHs in a saturated porous matrix(Scholarlink Research Institute Journals, 2014) Azeez, Taofik Oladimeji; Arinkoola, Akeem Olatunde; Salam, Kazeem Kolapo; Nwakaudu, Madueke StanleyThe commercial implementation of biodegradation of polycyclic aromatic hydrocarbons (PAHs) as a bioremediation technique against physical process was due to lack of its effective and efficient diffusivity model with reaction parameters in a saturated porous matrix. The development and simulation of diffusivity model which involve reaction kinetics was aimed to provide quantitative insight on biodegradation of PAHs. The developed model obtained from the principle of conservation of matter, concepts of Fick’s law of diffusion, Malthus equation and Monod kinetics expression under isothermal condition was simulated with experimental data. The result showed that Corynebacterium sp and Pseudomonas putida were effective and PAHs exhibits pseudo first order reaction. Though, the effective diffusivity of PAHs decreases as degradation of PAHs proceeds with increased microbial mass concentration at increased penetration depth. The developed diffusivity model has been shown to be effective and not only providing quantitative insight into biodegradation of the PAHs but serves as an alternative option in the selection of microbes capable of facilitating the restoration of PAHs contaminated sites.Item Open Access Optimization of biodegradation of anthracene by corynebacterium sp and psuedomonas putida(U. P., 2015-05) Azeez, Taofik Oladimeji; Owabor, Chiedu Ngozi; Nwakaudu, Madueke Stanley; Usondu, Nnamuzie FrancisThe carcinogenic potential of industrial effluent discharged of anthracene on the ambient environment with contamination to soils and aquifers is not only environmental concern but difficulty in implementation of biodegradation of anthracene due to inability to optimizing the process parameters. The optimization of process parameters for biodegradation of anthracene with the activity of Corynebacterium sp and Pseudomonas putida using response surface methodology was aimed to be investigated. A 23 of full factorial central composite design was employed for developed quadratic polynomial model to achieve optimal performance of the process. Statistically, high correlation coefficient (R2) for quadratic polynomial model for biodegradation of anthracene by activity of Corynebacterium sp 0.9659 (p<0.05)and Pseudomonas putida 0.9939 (p<0.05) were obtained. The optimum conditions for anthracene degradation by Corynebacterium sp were 69.99g/L, 83.20hours and 3.4735vvm with about 98.48 percent of anthracene degraded while Pseudomonas putida were 69.989g/L, 3.58hours and 3.5vvm with 89.51percent of anthracene degraded.Item Open Access Modeling of Nigerian peak petroleum resources depletion using turbulent flow regime with dead time(U. P., 2015-07) Kamalu, C. I.; Nnebue, N. C.; Madu, I. K.; Kamen, F. L.; Effiong, E. E.; Obibuenyi, J. I.; Uzoije, A. P.Seven simple physical non-linear, mathematical models for petroleum resource depletion for Nigeria were developed by varying the input functions of the laplace domain of the models. The models were validated with data collected from the Department of Petroleum Resources (DPR), Ministry of Petroleum Resources, Nigeria, using MATLAB 7.9 software. As a control, these models were compared with an existing model by Hubert and found to be generally better. Two best models (III and V), with R2 of 99.696% (oil), 99.680% (gas) and R2 of 99.695% (oil), 99.641% (gas) respectively compared to Hubbert’s model with R2 of 98.67% (oil), 99.26% (gas), were selected out of seven (VII) models. The plots of the derivatives of the models which gave the annual production profile were also used to determine the peak and exhaustion periods for both oil and gas. The results were within range 2062 - 2121AD and 748982AD (infinity) respectively for oil production peak and exhaustion, and within the value 2782AD and 13853AD (infinity) respectively for gas production peak and exhaustion from 1957AD. The oil and gas ultimate recovery reserves were subsequently determined at 641.3TB and 5729Qscf respectively. Hence, even though the oil will peak before gas, gas will exhaust before oil. However, this can be due to the slight lower R2 of gas as compared to that of the oilItem Open Access Proxy model for optimization of biodegradation of pyrene by corynebacterium sp and pseudomoas putida(U. P., 2015-11) Azeez, Taofik Oladimeji; Owabor, Chiedu Ngozi; Nwakaudu, Madueke Stanley; Opebiyi, SampsonA proxy model for optimization of operating conditions (pyrene concentration, biodegradation time and aeration) for biodegradation of pyrene by Corynebacterium sp and Pseudomonas putida was aimed to be investigated. The proxy model for biodegradation of pyrene with activity of Corynebacterium sp and Pseudomonas putida was developed from experimental data using response surface methodology (RSM) with central composite design (CCD) of the design of experiments software. Corynebacterium sp degraded 96.71 % of pyrene at optimal conditions of 68.16 mg/L of pyrene concentration, biodegradation time of 82.57 hours and aeration condition of 3.0125vvm, while Pseudomonas putida degraded 93.84 % of pyrene at optimal conditions of 69.90 mg/L of pyrene concentration, biodegradation time of 84 hours and aeration condition of 3.4995 vvm. The developed proxy model of biodegradation of hazardous pyrene disposal under the stated operating conditions is fit and acceptable for optimization.