Journal of Environmental Engineering and Technology

ISSN 2165 - 8315 (Print)

ISSN 2165 - 8307 (Online)

Website: http://www.researchpub.org/journal/jeet/jeet.html


Conversion of Methane to Methanol by a Low-Pressure Steam Plasma
Author(s) Takayuki Tsuchiya and Satoru Iizuka

The paper investigates the performance of different bandpass modulation techniques in Additive White Gaussian Noise (AWGN) Channel and Multipath fading channel. This study examines the inherent attributes of the digital modulation to overcome the channel impairments. It reviews digital modulation techniques. The two channels- AWGN and Multipath channels were modeled and simulated in MATLAB Environment. The evaluation of the different modulation techniques was carried on the modeled channels. This was carried out to understand the contributions of channel characteristics to effective wireless communication. The BER for simulated modeled channels agreed with the theoretical results.. The performance of 64QAM is better compared to other bandpass modulation schemes in AWGN Channel. It was observed that the BER is higher in frequency selective channel as compared to the AWGN channel. It was also observed that multipath fading channel characteristic limits the data rate in wireless communication.

[1] L. M. Zhou, B. Xue, U. Kogelschatz, B. Eliasson, Partial oxidation of methane to methanol with oxygen or air in a nonequilibrium discharge plasma, Plasma Chem. Plasma Process. 1988, 18, 375.
[2] B. Eliasson, C-J. Liu, U. Kogelsschatz, Direct conversion of methane and carbon dioxide to higher hydrocarbons using catalystic dielectric-barrier discharges with zeolites, Ind. Eng. Chem. Res. 2000, 39, 1221.
[3] K. Zang, B. Eliasson, U.Kogelschatz, Direct conversion of greenhouse gases to synthesis gas and C4 hydrocarbons over zeolite HY promoted by a dielectric-barrier discharge, Ind. Eng. Chem. Res. 2002, 41, 1462.
[4] S. A. Nair, T. Nozaki, K. Okazaki, In situ Fourier transform infrared (FTIR) study of nonthermal-plasma-assisted methane oxidative conversion, Ind. Eng. Chem. Res. 2007, 46, 34886.
[5] R. Lodeng, O. A. Lindvag, P. Soraker, P. T. Roterud, O. T. Onsager, Experimental and modeling study of the selective homogeneous gas phase oxidation of methane to methanol, Ind. Eng. Chem. Res. 1995, 34, 1044.
[6] P. S. Casey, T. Macallister, K. Foger, Selective oxidation of methane to methanol at high pressures, Ind. Eng. Chem. Res. 1994, 33, 1120.
[7] L.K. R-Struckmann, A. Peschel, R. H-Rausehenbach, K. Sundmacher, Assesment of methanol sysnthesis utilizing exhaust CO2 for chemical strage of electric energy, Ind. Eng. Chem. Res. 2010, 49, 11073.
[8] S.L. Yao, T. Takemoto, F. Outang, A. Nakayama, E. Suzuki, A. Mizuno, M. Okamoto, Selective oxidation of methane using a non-thermal pulsed plasma, Energy Fuels, 2000, 14, 459.
[9] D. W. Larkin, L. Lobban, R. G. Mallinson, production of organic oxygenates in the partial oxidation of methane in a silent electric discharge reactor, Ind. Eng. Chem. Res. 2001, 40, 1594.
[10] A. Indarto, D. R. Yang, J. Palgunadi, J. W. Choi, H. Lee, H. K. Song, Partial oxidation of methane with Cu-Zn-Al catalyst in a dielectric barrier discharge, Chem. Eng. Process. 2008, 47, 780.
[11] C. H. Tsai, T. H. Hsieh, New approach for methane conversion using rf discharge reactor. 1. Influences of operating conditions on syngas production, Ind. Eng. Chem. Res, 2004, 43, 4043.
[12] M. Kano, G. Satoh, S. Iizuka, Reforming of carbon dioxide to methane and methanol by electric impulse low-pressure discharge with hydrogen, Plasma Chem. Plasma Process. 2011, DOI 10.1007/s11090-011-9333-0.
[13] B. Eliasson, U. Kogelschatz, B. Xue, L. M. Zhou, Hydrogeneration of carbon dioxide to methanol with a discharge-activated catalyst, Ind. Eng. Chem. Res, 1998, 37, 3350.

Performance Studies on Wastewater Treatment Efficiency of an Artificial Wetland
Author(s)S. Ramakrishna Rao, S. Bala Prasad, P. S. Raja Sekhar and S.A. Rahiman

One of the reasons for deterioration of quality of lakes is the discharge of wastewater into them. The Kolleru Lake is one such natural fresh water wetland in Andhra Pradesh which has International importance as it was classified under Ramsar Convention. Its water quality is deteriorating due to discharge of inflows through small streams of untreated sewage generated from the surrounding towns and human activities in Krishna-Godavari delta region. It is essential to restore the quality of lake water. Among the existing low-cost treatment option for the treatment of inflow wastewater. Artificial wetland may be considered as viable treatment option for the treatment of inflow wastewater into Kolleru Lake. Hence, in the present study a lab scale artificial wetland system is developed and used to estimate the pollutants removal efficiency from the wastewater in three different seasons. Treatment effectiveness was evaluated which indicated the percentage values of mean removal efficiencies estimated in the Winter, Summer and Monsoon seasons for the parameters viz., TDS, TSS, BOD, COD, Nitrates and Phosphates are 34.13±1.41%, 41.45±7.71% and 36.83±2.60%;46.51±2.74%, 59.76±5.88% and 52.76±3.80%; 48.85±4.38%,60.29±8.31% and 54.11±5.19%; 46.35±3.74%, 54.01±3.53% and 50±.2.3%; 47.61±3.75%, 55.23±5.43% and 52.05±4.61%;38.61±3.39%, 49.71±1.15% and 42.05±2.56% respectively. The findings indicate that artificial wetland system is effective in removing pollutants from the wastewater.ely). It is observed that Bragg resonance occurs at the critical condition with the ratio 2S/L = 1.0 for all the cases of artificial beds considered, and maximum reflection appears as Bragg resonance occurs. It is also found that reflection coefficient from the sinusoidal artificial bed is much higher than those on other undulations which being similar for 2S/L different from unity. From the amplitude evolution analysis for each artificial bed, the first harmonic presents a regular oscillatory variation and gradually decays through wave traveling over artificial bed in the case with 2S/L =1. The second harmonic becomes significant in the cases with 2S/L<1, due to vortex generation in the flow field. The antinodes of standing wave due to Bragg resonance are consistently located at the front edge of an undulation patch, and the nodes in the lee side.

[1] Aditya Kishore Dash. Efficiency Study of two wetland treatment systems at Bhubaneswar. India A case study. The Bioscan. Special issue. An international quarterly journal of life sciences 2010; 3:701-711.
[2] Atif Mustafa. Constructed Wetland for Wastewater Treatment and Reuse: A Case Study of Developing Country. International Journal of Environmental Science and Development 2013;4(1):20-24.
[3] Babatunde. A.O. Zhao. Y.Q. O'Neill. M. & O'Sullivan. B. Constructed wetlands for Environmental pollution control: A Review of developments. research and practice in Ireland. Environment International 2008; 34(1):116–126.
[4] Bala Prasad. S. Ramakrishna Rao. S.. Rahiman. S.A. Restoration of Kolleru Lake water quality using artificial wetland system-A case study in The Bioscan. Special issue. An international quarterly journal of life sciences 2010;3:713-719.
[5] Brion Moss. The influence of environmental factors of the distribution of fresh water algae on experimental study. The role of pH. Carbon dioxide and bicarbonate system. J. of Ecol 1973; 6(1): 157.
[6] Carty. A.. Scholz. M.. Heal. K.. Gouriveau. F.. & Mustafa. A. The Universal design. operation and maintenance guidelines for Farm Constructed Wetlands (FCW) in temperate climates Bioresource Technology 2008; 99(15):6780 – 6792.
[7] Faulwetter JL. Sundbergc GV. Chazarencd F. Burra MD. Brissonb J. Campera AK. Steina. Microbial processes influencing performance of treatment wetlands: a review. Ecol Eng 2009; 35: 987–1004
[8] Gersberg. R.H.. Elkins. B.V.. Lyon. S.R.. and Goldman. C.R. Role of aquatic Plants in wastewater Treatment by Artificial Wetlands. Water Research 1986. Vol. 20: 363-368.
[9] Gohram. The chemical composition of some waters from Dune slacks at Sandscale. North Lancashire. J. Ecol. 1961; 49(1): 79-82.
[10] Greenway. M. The role of constructed wetlands in secondary effluent treatment and water reuse in subtropical and arid Australia. Ecological Engineering. 2005; 25(1): 501?509.
[11] Haberl. H. Erb. K. H. Krausmann. F. Adensam. H & Schulz. N. Land-use change and socioeconomic metabolism in Austria. part II: Land-use scenarios for 2020. Land Use Policy. 2003; 20(1): 21–39.
[12] Jayakumar.K.V and Dandigi. M.N. A Study on the Use of Constructed Wetlands for Treatment of Municipal Wastewater during Summer and Monsoon seasons in a Semi Arid City in India. Proceedings of 9th International Conference on Global Solutions for Urban Drainage (9ICUD). 2002.
[13] Jawale. A.K. and S.A. Patil. Physico-chemical characteristics and Phytoplanktons abundance of Mangrul dam. Dist-Jalgaon. Maharashtra. J. Aqua. Biol. 2009; 24(1): 7-12
[14] Kadlec. R. H.. Knight. R. L.. Vymazal. J.. Brix. H.. Cooper. P.. & Haberl. R. Constructed wetlands for pollution control. Scientific and technical report no. 8. London: IWA. 2000.
[15] Kinwaka. S.R.A.kaggwa. Sekayizz and T.O.Okurut. Muncipal wastewater effluent quality improvement and experiences – use of a tropical integrated reconstructed natural wetland in Uganda. Masaka VIII International Conference on wetland Systems for Water Pollution Control.Arusha.Tanzania.IWA Publications. 2002; 1:333-337
[16] K?ner S. Lyatuu G.B. and Vermaat J.E.The influence of Lemna gibba L.on the degradation of organic material in duckweed-covered domestic wastewater. Water Research. 1998; 32(10). 3092-3098.
[17] Kutty. S. R. M.. Ngatenah. S. N. I.. Isa. M. H. and Malakahmad. A. Nutrient removal from municipal waste water treatment plant effluent using Eichhornia crassipes. World academy of science. Engineering and Technology. 2009: 826-831
[18] Larsen E. Greenway M. Quantification of biofilms in a subsurface flow wetland and their role in nutrient removal. Water Sci Technol. 2004; 49:115–122
[19] Mahmood. Q.. P. Zheng. E. Islam. Y. Hayat. M. J. Hassan. G. Jilani. R. C. Jin. Lab Scale Studies on Water Hyacinth (Eichhornia crassipes Marts Solms) for Bio treatment of Textile Wastewater. Caspian J. Env. Sci. 2005; 3(2): 83-88.
[20] Mzrzppa Jayanthi. Peter Nila Rekha. Natarajan Kavitha. Pitchaiyappan Ravichandran. Assessment of impact of aquaculture on Kolleru Lake (India) using remote sensing and Geographical information system. Aquaculture Research. 2006;37(16):1617-1626
[21] Narayana. J.. E.T. Puttaiah and D. Basavaraja. Water quality characteristics of anjanapura reservoir near Shikaripur. District Shimoga. Karnataka J. Aqua. Biol. 2008; 23(1): 59-63.
[22] Rajashekhar. A.V.. A. Lingaiah. Satyanarayana Rao and Ravi Shankar Piska. The studies on water quality parameters of a minor reservoir. Nadergul. Rangareddy district andhra Pradesh. J. Aqua. Biol. 2007; 22(1): 118-122.
[23] Ramakrishna Rao.S. Krishna. A & Rama Rao. R.V. An integrated approach for the restoration of polluted Lake Kolleru. Conference of the Israel Society for Ecology & Environmental quality Sciences. Bar Ilan University Press. Israel. 1986.
[24] Ramakrishna Rao.S. Lakshmi Sujatha. B. “Ecological Modelling of Kolleru Lake Transformations Tech”. Thesis: 97. 1996.
[25] Reed. S.C.. Middle brooks. E.J.. Crities. P.W. Natural systems for waste Management and treatment. McGraw Hill. New York. NY. 1988.
[26] Reed. S.C. Nationwide Inventory: Constructed Wetlands for Wastewater Treatment. Biocycle 1991; 32(1): 44–49.
[27] R. H. Kadlec and S. Wallace. Treatment Wetlands; Boca Raton: CRC. 2009; ch.1 & ch.6-9
[28] Solano. M. L. Soriano. P. & Ciria. M.P. Constructed wetlands as a Sustainable solution for wastewater treatment in small villages. Biosystems Engineering. 2003; 87(1):109–118.
[29] Soukup. A.. Williams. R. J.. Cattell. F. C. R.. & Krough. M. H. The function of a coastal wetland as an efficient remover of nutrients from sewage effluent: A case study. Water Science and Technology. 1994;29(4): 295–304.
[30] Scholz. M. Wetland systems to control urban runoff. Amsterdam: Elsevier. 2006.
[31] Trivedi. R. K. and Goel. P. K. Chemical and biological methods for water pollution studies. Environmental publications Karad. India. 1987.
[32] U.S.EPA Manual. Constructed treatment of Municipal wastewater design Manual. 2000.
[33] Venkata Rao.. Bibi. S.K.. Malleshwara Rao.P. Water Quality Studies of Kolleru Lake. Upputeru River and Enamaduru Drain. Indian J. Environmental Protection. 2006; 26(6).
[34] Vymazal. J. Removal of nutrients in various types of constructed wetlands. Science of the Total Environment. 2007; 380(1–2):48–65.
[35] Vymazal. J. Constructed wetlands for wastewater treatment: five decades of experience. Environmental Science and Technology. 2010; 45(1): 61–69.
[36] Wijetunga.S. D.H.U. Sandamali and K.D.N. Weerasinghe. Evaluation of efficacy in the treatment of domestic wastewater by different aquatic macrophytes. Journal of Environmental Research And Development. 2009; 4(2).
[37] Woltemade C. Ability of restored wetlands to reduce nitrogen and phosphorus concentrations in agricultural drainage water. J Soil Water Conserv. 2000; 55:303–309.
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