Joseph Patrick Hettiaratchi
MEng - Environmental Engineering
BSc - Civil Engineering
Preferred method of communication
- Engineering for the environment
- Renewable energy
- Biomass waste to energy
Over the last two decades, Dr. Hettiaratchi has undertaken a number of studies in the field of environmental and human health protection: anaerobic digestion of carbonaceous waste/sewage in small scale digesters, the use of fly ash from coal power plants to construct landfill liners/covers and vertical thin walls at waste impoundments, landfill stabilization, softwater corrosion of water conveyance systems, sustainable landfill technology, methanotrophic applications to control methane emissions from the oil and gas industry and sanitary landfills, evaluation and estimation of methane and non-methane organic compounds (NMOCs) from municipal and industrial landfills, and composting of organic waste.
Biocell technology development research
Several major contributions have resulted from the research associated with the Biocell Technology research program. The award winning Biocell concept involves the operation of a waste cell sequentially in the anaerobic (maximum gas/energy recovery) and aerobic (rapid waste stabilization) modes followed by mining to recover reuse derived fuel (RDF) and space. We received two NSERC strategic grants and the city of Calgary provided more than $3 million in-kind support for the research. Some of the selected papers (shown below) published in refereed journals over shows the contributions in related topics such as biomass waste to energy kinetics, waste settlement and stabilization, laboratory research to develop enzyme augmentation of recirculating leachate.
Methane biofilter technology research
Over the last 5 years, continued to develop and produce major contributions to advance methane biofilter technology. Methane biofilter is one of the most cost effective techniques to control point source methane (a key greenhouse gas) emissions. My team has conducted pioneering work in this area over more than a decade to develop it as a viable technology. The contributions are in developing design parameters, mathematical modeling and experience with field operation and high rate oxidation in actively aerated biofilter systems. A high-rate methane biofilter (HMBF) is currently in operation at an oil faciity in Hanna, Alberta.
Evapotranspirative landfill biocovers
A multi-million-dollar project is currently being implemented to demonstrate the effectiveness of ET-LBC technology, which is a hybrid of landfill biocover technology to mitigate fugitive methane emissions from landfills and evapotranspiration (ET) based alternatives to the traditional approach of using impervious barrier covers. TetraTech EBA, Leduc waste authority and Climate Change Emissions management Corporation (CCEMC), supports this project. Field demonstrations of this technology are underway at sites in Leduc and Okotoks. The successful completion of the ET-LBC project will be highly beneficial to Canadians considering that large-scale deployment of ET-LBC technology will help Alberta and Canada achieve their greenhouse emission reduction targets.
Dr. Patrick Hettiaratchi received his MEng from Asian Institute of Technology and PhD from the University of Alberta. Prior to joining the University of Calgary in 1996, he had consulted extensively in the area of environmental engineering, specifically in the fields of landfill technology, solid waste and wastewater treatment process design, air quality and human health risk assessment. He has actively participated in contaminated site assessments and the development of site remediation plans for the petroleum industry.
Dr. Hettiaratchi has participating in several international collaborative research/education projects in Asia and South America. The Asian Regional Landfill study has partners from Thailand, China, India, Sri Lanka and Asian Institute of Technology (AIT, Bangkok). The FONDEF project participants include University of Catolica (Valparaiso, Chile) and University of Cantabria (Spain). The OLADE project involves participants from 20 countries in Latin America and the Caribbean.
2018. Hawkins, J., Lina, K., Hettiaratchi, J. P. A., Joshua, T., Getachew, A. 2018. Spatial Statistical Analysis of Infrastructure Systems in Calgary, Alberta. Journal of Environmental Planning and Management. https://doi.org/10.1080/09640568.2018.1523052
2018. Meegoda, J. N., Soliman, A., Hettiaratchi, J. P.A., Agbakpe, M. 2018. Resource Mining for a Bioreactor Landfill. Current Environmental Engineering. https://doi.org/10.2174/2212717805666181031122517
2018. Gunasekara, S., Hettiaratchi, J. P. A, Bartholameuz, E., Farrokzadeh, H., Irvine, E. 2018. A comparative evaluation of the performance of full-scale high-rate methane biofilter (HMBF) systems and flow-through laboratory columns. Environmental Science and Pollution Research Pages 1-10. https://doi.org/10.1007/s11356-018-3100-1
2018. Helen, L., Hettiaratchi, J. P. A., Achari, G., Dunfield, P. 2018. Investigation of Biologically Stable Biofilter Medium for Methane Mitigation by Methanotrophic Bacteria. ASCE Journal of Hazardous and Radioactive Waste 22(3):04018013. https://doi.org/10.1061/(ASCE)HZ.2153.5515.0000406
2018. Helen, L., Hettiaratchi, J. P. A., Achari, G., Verbeke, T. J., Dunfield, P. 2018. Biofiltration of Methane Using Hybrid Mixtures of Biochar, Lava Rock and Compost. Environmental Pollution, 241, 45-54. https://doi.org/10.1016/j.envpol.2018.05.039
2018. Helen, L., Hettiaratchi, J. P. A., Achari, G., Dunfield, P. 2018. Biofiltration of Methane. Bioresource Technology, 268, 759-772.
2018. Pearse, L. F., Hettiaratchi, J. P. A., Kumar, S. 2018. Towards Developing a Representative Biochemical Methane Potential (BMP) Assay for Landfilled Municipal Solid Waste - A Review. Bioresource Technology, 254, 312-324.
2018. Saidi, S., Kattan, L., Jayasinghe, P., Hettiaratchi, J. P. A., Taron, J. 2018. Integrated Infrastructure Systems - A Review. Sustainable Cities and Society 36, 1-11.
2017. Barzgar, S., Hettiaratchi, J. P. A., Pearse, L., Kumar, S. 2017. Inhibitory Effects of Acidic pH and Confounding Effects of Moisture Content on Methane Biofiltration. Bioresource Technology 245 (Part A), 633-640.
2017. Farrokzadeh, H., Hettiaratchi, J. P. A., Jayasinghe, P. A., Kumar, S. 2017. Aerated Biofilters with Multiple-Level Air Injection Configurations to Enhance Biological Treatment of Methane Emissions. Bioresource Technology 239, 219-225.
2016. Mancebo, U., Hettiaratchi, J. P. A., Jayasinghe, P.A., Surampalli, R. 2016. Determination of water retention capacity of granular media of methane biofilters: A simplified approach. Environmental Earth Sciences 75(1) 1-8
2016. Hettiaratchi, J. P. A. 2016. Editorial (Thematic Issue: Greenhouse Gas Emission Reduction Using Biological Methods) Source: Current Environmental Engineering 3, (2) 78-79.
2016. Jayasinghe, P. A., Haththotuwa, C. K., Hettiaratchi, J. P. A. 2016. Methane Biofiltration in the Presence of Non-Methane Organic Compounds in Solution Gas. Current Environmental Engineering 3, (2) 161-169.
2016. Meegoda, J. N., Bhuvaneshwari, S., Hettiaratchi, J. P. A., Hettiarachchi, H. 2016. A Comprehensive Model for Anaerobic Degradation in Bioreactor Landfills. Current Environmental Engineering 3 (2), 181-193.
2016. Bartholameuz, E. M., Hettiaratchi, J. P. A. 2016. Evaluating Aeration Configurations in Aerobic Landfills. Current Environmental Engineering 3 (2), 107-117
2016. Pokhrel, D., Hettiaratchi, J. P. A., Steele, M. 2016. Methane Oxidation Prediction Curves of Soil at Different Organic Contents. Current Environmental Engineering, 3 (2), 131-143.
2016. Bartholameuz, E. M., Hettiaratchi, J. P. A., Kumar, S. 2016. Enhanced performance of the aerobic landfill reactor by augmentation of manganese peroxidase. Bioresource Technology 218, 46-52.
2015. Mancebo, U., Hettiaratchi, J. P. A. 2015. Rapid assessment of methanotrophic capacity of compost-based materials considering the effects of air-filled porosity, water content and dissolved organic carbon, Bioresource Technology 177, 125-133.
2015. Hettiaratchi, J. P. A., Jayasinghe, P. A., Tay, J. H., Yadav, S. K. 2015. Recent advances in biomass to energy using landfill bioreactor technology, Current Organic Chemistry 19(5), 413-422.
2014. Jayasinghe, P. A., Hettiaratchi, J. P. A., Mehrotra. A. K. 2014. Reaction mechanism and rate constants of waste degradation in landfill bioreactor systems with enzymatic-enhancement, Bioresource Technology 162, 279-282.
2014. Hettiaratchi, J. P. A., Jayasinghe, P. A., Bartholameuz, E. M., Kumar, S. 2014. Relative rates of waste degradation and gas production with enzymatic enhancement in anaerobic and aerobic landfill bioreactors. Bioresource Technology 159, 433-436.
2013. Hettiarachchi, C. H., Hettiaratchi, J. P. A., Hunte, C., Meegoda, J. N. 2013. The City of Calgary Biocell: Operation of a Landfill Bioreactor in a Cold Climate: Early Results and Lessons Learned. Bioreactor Landfills: Special Issue of ASCE Journal of Hazardous and Radioactive Waste.
2013. Somathileke, P., Hettiaratchi, J. P. A. 2013. Struvite Formation in Leachate Recirculation Pipes of Bioreactor Landfills. Journal of Solid Waste Technology and Management 38, 291-299.
2012. Mancebo, U., Hettiaratchi, J. P. A., Hurtado, O. D. 2012. A Study on the Correlation Between Dissolved Organic Carbon, Specific Oxygen Uptake Rate, and Exchangeable Nitrogen and the Performance of Granular Materials as Support Media for Methanotrophic Biofiltration. Journal of Hazardous, Toxic, and Radioactive Waste, 121130231809003
2012. Jayasinghe, P. A., Hettiaratchi, J. P. A., Mehrotra, A. K., Steele, M. A. 2012. Enhancing gas production in landfill bioreactors: A flow-through column study on leachate augmentation with enzyme. Bioreactor Landfills: Special Issue of ASCE Journal of Hazardous and Radioactive Waste.
2012. Hettiarachchi, C. H., Hunte, C., Hettiaratchi, J. P. A., Meegoda, J. N. 2012. The City of Calgary Biocell Landfill: Data Collection and Settlement Predictions using a Multiphase Model. Advances in Geotechnical Engineering, ASCE Geotechnical Special Publication. 225, 4202-4211.
2011. Jayasinghe, P. A., Hettiaratchi, J. P. A., Mehrotra. A. K., Kumar, S. 2011. Enzymatic Enhancement of Leachate to Increase Gas Production in Landfill Bioreactors, Bioresource Technology 102(7), 4633-4637.
2011. Hunte, C., Hettiaratchi, J. P. A., Meegoda, J. N., Hettiarachchi, C. H. 2011. Determination of Waste Properties from Settlement Behaviour of a Full-Scale Waste Cell Operated as a Landfill Bioreactor. Advances in Geotechnical Engineering ASCE Geotechnical Special Publication 211, 1404-1413.
2011. Hettiaratchi, J. P. A., Hunte, C., Meegoda, J. N., Hettiarachchi, C. H. 2011. Performance of a Waste Cell in Cold Climate Operated as an Anaerobic Landfill Bioreactor. Advances in Geotechnical Engineering, ASCE Geotechnical Special Publication 211, 1276-1286.
2011. Hettiarachchi, V., Hettiaratchi, P. 2011. Field-scale operation of methane biofiltration systems to mitigate point source methane emissions. Environmental Pollution 159(6), 1715-1720.
2011. Pokhrel, D., Hettiaratchi, J. P. A., Kumar, S. 2011. Methane diffusion coefficient in compost and soil-compost mixtures in gas phase biofilter. Chemical Engineering Journal 169(1-3), 200-206.
2010. J. Hettiaratchi, H. Hsieh, J. N. Meegoda, and C. A. Hunte. 2010. Sustainable Management of Household Solid Waste. International Journal of Environment and Waste Management (IJEWM), 6 (Issue 1-2), 96-106.
2010. NilanthiJ. G. J. Bandara, and J.P.A Hettiaratchi, 2010. Environmental Impacts with Waste Disposal Practices in a Suburban Municipality in Sri Lanka International Journal of Environment and Waste Management (IJEWM), 6(1-2) 107-116 (July 2010)
2009. C. H. Hettiarachchi, J. N. Meegoda and J.P.A. Hettiaratchi 2009. Effects of gas and moisture on modeling of bioreactor landfill settlement. Journal of Waste Management Vol. 29, Issue 3, Pages 1018-1025, (March 2009).
2009. I.E.T. Soh, and J.P.A. Hettiaratchi, 2009. Potential Lateral Migration of Leachate in Flushing Bioreactor Landfills during Aggressive Leachate Recirculation. ASCE Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management Volume: 13 Issue: 3 pp. 174-178 (July 2009)
2009. J.P.A. Hettiaratchi, I.E.T. Soh, C. Hunte 2009. Evaluation of an Alternative Method of Leachate Collection System Design. ASCE Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management Volume: 13 Issue: 3 ) pp. 156-164 (July 2009) (pdf)
2009. J.P.A. Hettiaratchi 2009. Advances in Solid Waste Management Technology: The way forward. HZ/2008/022530. ASCE Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management; Vol. 13 Issue: 3 (July 2009)
2008. H. Hsieh, J. N. Meegoda, J. P.A. Hettiaratchi, S. El Haggar, and R. I. Stessel. 2008. Towards the Development of Sustainable Landfills. ASCE Geotechnical Special Publication #177, The Challenge of Sustainability in the Geo-environment, pp. 344-351.
2008. Jenny Sanderson, Patrick Hettiaratchi, Carlos Hunte, Omar Hurtado, Alejandro Keller 2008. Methane Balance of a Bioreactor Landfill in Latin America. Journal of Air and Waste Management Association 2008; 58 (5) pp. 622-628.
2008. K. Perdikea, A. Mehrotra and J.P.A. Hettiaratchi, 2008. Study of thin biocovers (TBC) for oxidizing uncaptured methane emissions in bioreactor landfills. Journal of Waste Management, Vol. 28, Issue 8, pp. 1364-1374.
2008. Perdikea, K., Mehrotra, A., & Hettiaratchi, J. P. A. 2008. Study of thin biocovers (TBC) for oxidizing uncaptured methane emissions in bioreactor landfills. Waste management, 28(8), 1364-1374.
2007. R. Saint-Fort, Mirtyl Alboiu, and J.P.A. Hettiaratchi, 2007. Evaluation of TENORMs Field Measurement with Actual Activity Concentration in Contaminated Soil Matrices. Journal of Environmental Science and Health, Part A - Toxic/hazardous Substances & Environmental Engineering. Vol. A42, (11) /September 2007, pp. 1649-1654.
2007. C. H. Hettiarachchi, J. N. Meegoda and J.P.A. Hettiaratchi 2007. Prediction of Waste Settlement in Bioreactor Landfills Incorporating Waste Biodegradation. ASCE Geotechnical Special Publication #152- GeoDenver2007, ISBN # 0784408971.
2007. C. Hunte, J.P.A. Hettiaratchi, J. N. Meegoda and C. H. Hettiarachchi 2007. Settlement of Bioreactor Landfills during Filling Operation. ASCE Geotechnical Special Publication #152- GeoDenver2007, ISBN # 0784408971.
2007. C.H., Hettiarachchi, J. Tavantzis, J.N. Meegoda, J.P.A Hettiaratchi 2007. Numerical Model to Predict Settlements Coupled with Landfill Gas Pressure in Bioreactor Landfills. Journal of Hazardous Materials, B139, 514–522.
2007. K.V.H. Ohman, J.P.A Hettiaratchi, J. Ruwanpura, J. Balakrishnan, G. Achari 2007. Development of a Landfill Model to Prioritize Design and Operating Objectives. Journal of Environmental Monitoring and Assessment. Vol. 135, Numbers 1-3, 85-97.
2007. C. Chiemchaisri, W. Chiemchaisri, Sunil Kumar and J. P. A. Hettiaratchi 2007. Solid waste characteristics and their relationship to gas production in tropical landfill. Environmental Monitoring and Assessment, Volume 135, Numbers 1-3 / December, 2007, pp. 41-48.
2007. Nilanthi J.G.J. Bandara, J.P.A Hettiaratchi, S.C. Wirasinghe, and Sumith Pilapiiya 2007. Relation of Waste Generation and Composition to Various Socio-Economic Factors. Environmental Monitoring and Assessment: 135(1-3), 31-39.
2007. Hettiarachchi, V., Hettiaratchi, J. P. A., & Mehrotra, A. K. 2007. Comprehensive one-dimensional mathematical model for heat, gas, and moisture transport in methane biofilters. Practice Periodical of Hazardous, Toxic, And Radioactive Waste Management, (11), 225-233.
2006. D.G.M. Senevirathna, G. Achari, and J.P.A. Hettiaratchi 2006. A laboratory evaluation of errors associated with the determination of landfill gas emissions. Canadian Journal of Civil Engineering, 33(3), 240-244.
2006. P.L. Amatya, J.P.A. Hettiaratchi, and R.C. Joshi. 2006. Interaction Effects of Metals and Salinity on Biodegradation of a Complex Hydrocarbon Waste. Journal of Air and Waste Management Association, Vol. 56, 197-205.
2006. Senevirathna, D. G. M., Achari, G., & Hettiaratchi, J. P. A. 2006. A mathematical model to estimate errors associated with closed flux chambers. Environmental Modeling & Assessment, 12(1), 1-11.
2005. C. H. Hettiarachchi, Hettiaratchi, J. P. A. and J. Meegoda. 2005. Towards a Fundamental Model to Predict the Settlements in Bioreactor Landfills. Waste Containment and Remediation - ASCE Geotechnical Special Publication # 142, January 2005, ISBN # 078440769X.
2005. Chandrakanthi, M., Mehrotra, A., & Hettiaratchi, J. 2005. Thermal conductivity of leaf compost used in biofilters: An experimental and theoretical investigation. Environmental pollution, 136(1), 167-174.
2004. L.A.K. Perera, G.A. Achari and J.P.A. Hettiaratchi. 2004. An assessment of the spatial variability of greenhouse gas emissions from landfills: A GIS based statistical-numerical approach. Journal of Environmental Informatics, 4(1) 2004, 11-30. (pdf)
2004. Wilshusen, J. H., Hettiaratchi, J. P. a, & Stein, V. B. 2004. Long-term behavior of passively aerated compost methanotrophic biofilter columns. Waste management, 24(7), 643–653.(pdf)
2004. Wilshusen, J., Hettiaratchi, J. 2004. Methane oxidation and formation of EPS in compost: effect of oxygen concentration. Environmental Pollution, 129(2), 305-314.
2002. L.A.K. Perera, G. Achari, and J.P.A. Hettiaratchi. 2002. Determination of source strength of landfill gas: A numerical modeling approach, ASCE Journal of Environmental Engineering, Volume 128, Issue 5, 461-471.
2002. M.D.N. Perera, J.P.A. Hettiaratchi, and G. Achari. 2002. A mathematical modeling approach to improve the point estimation of landfill gas surface emissions using the flux chamber technique. Journal of Environmental Engineering and Science Vol. 1, Issue 6, 451-463. (pdf)
2002. Perera, M. D. N., Hettiaratchi, J. P. A., & Achari, G. 2002. A mathematical modeling approach to improve the point estimation of landfill gas surface emissions using the flux chamber technique. Journal of Environmental Engineering and Science, 1(6), 451–463. (pdf)
2001. J.P.A. Hettiaratchi, P.L. Amatya, E.A. Jordan, and R.C. Joshi. 2001. An Evaluation of Slurry-phase Experiments as a Screening Protocol for Bioremediation of a Complex Hydrocarbon Waste, ASCE Practice Periodical of Hazardous Toxic and Radioactive Waste Management, Vol. 5, No. 2, 88-98.
2001. Stein, V. B., & Hettiaratchi, J. P. A. 2001. Methane oxidation in three Alberta soils: influence of soil parameters and methane flux rates. Environmental technology, 22(1), 101-111.
2001. Stein, V. B., Hettiaratchi, J. P. A., & Achari, G. 2001. Numerical Model For Biological Oxidation And Migration Of Methane In Soils. Practice Periodical of Hazardous, Toxic, And Radioactive Waste
Albert E. Berry Medal, Canadian Society for Civil Engineering (CSCE) - 2013 (National)
Peak Scholar Award - University of Calgary (2015)
Fellow - Canadian Society for Civil Engineering (CSCE)- 2011 (National)
The Research Excellence Award – Department of Civil Engineering - 2009 (University)
The Royal Canadian Geographical Society and 3M Canada: Canadian Environmental Innovation Award, Finalist - 2009 (National)
Manning Innovation Awards: Southern Alberta Nominee - 2009 (National)
APEGA Summit Awards: Environment and Sustainability Award for the Calgary Biocell Project - 2009 (Provincial)
Shell/ASTECH Award for Environmental Innovation, 2008 Alberta Science and Technology (ASTech) Leadership Foundation - 2008 (Provincial)
Alberta Emerald Award for Research and Innovation - 2007 (Provincial)
Calgary Environmental Achievement Award, City of Calgary - 2006 (Municipal)
Russel Ackoff Award - 22nd International Conference on Solid Waste Technology and Management held in Philadelphia, PA - 2006 (International)
ASCE/EWRI Best Theoretical Paper Award, presented at the ASCE/CSCE Environmental Engineering Joint Conference, Niagara Falls, ON - 2002 (International)
Iraj Zandi Award - 17th International Conference on Solid Waste Technology and Management held in Philadelphia, PA - 2001 (International)