Chew Tin Lee

Bio: Chew Tin Lee is an academic researcher from Universiti Teknologi Malaysia. The author has contributed to research in topics: Compost & Municipal solid waste. The author has an hindex of 30, co-authored 152 publications receiving 3362 citations. Previous affiliations of Chew Tin Lee include University of Malaya & University of Cambridge.

Potential of biogas production from farm animal waste in Malaysia

Abstract: Anaerobic digestion of renewable feedstocks has been known as a prospective technology for the production of clean energy in the form of biogas. Biogas is a sustainable energy carrier which is mainly composed of methane (60%) and carbon dioxide (35–40%). Among the raw substances, organic matters obtained from farm animal waste are pivotal sources for biogas production. In recent years, the number of animal husbandry has drastically grown in Malaysia. Accordingly, a large amount of animal waste including manure, blood and rumen content are produced which provide a tremendous source of biogas generation. This paper presents biogas potential from the organic waste obtained from the farm animals and slaughterhouses in Malaysia. The findings of this study indicated that biogas potential of 4589.49 million m 3 year − 1 could be produced from animal waste in Malaysia in 2012 which could provide an electricity generation of 8.27×10 9 kWh year −1 .

Review of distributed generation (DG) system planning and optimisation techniques: Comparison of numerical and mathematical modelling methods

Abstract: An overview of numerical and mathematical modelling-based distributed generation (DG) system optimisation techniques is presented in this review paper. The objective is to compare different aspects of these two broad classes of DG optimisation techniques, explore their applications, and identify potential research directions from reviewed studies. Introductory descriptions of general electrical power system and DG system are first provided, followed by reviews on renewable resource assessment, load demand analysis, model formulation, and optimisation techniques. In renewable resource assessment model review, uncertain solar and wind energy resources are emphasised whereas applications of forecasting models have been highlighted based on their prediction horizons, computational power requirement, and training data intensity. For DG optimisation framework, (solar, wind and tidal) power generator, energy storage and energy balance models are discussed; in optimisation technique section, both numerical and mathematical modelling optimisation methods are reviewed, analysed and criticised with recommendations for their improvements. In overall, this review provides preliminary guidelines, research gaps and recommendations for developing a better and more user-friendly DG energy planning optimisation tool.

Biogas Developments and Perspectives in Europe

Abstract: This paper presents a review of the turn of events and points of view of biogas in and its utilization for power, heat and in transport in the European Union (EU) and its Member States. Biogas creation has expanded in the EU, empowered by the sustainable power strategies, notwithstanding monetary, ecological and atmosphere benefits, to arrive at 18 billion m3 methane (654 PJ) in 2015, speaking to half of the worldwide biogas creation. The EU is the world chief in biogas power creation, with more than 10 GW introduced and various 17,400 biogas plants, in contrast with the worldwide biogas limit of 15 GW in 2015. In the EU, biogas conveyed 127 TJ of warmth and 61 TWh of power in 2015; about half of absolute biogas utilization in Europe was bound to warm age. Europe is the world's driving maker of biomethane for the utilization as a vehicle fuel or for infusion into the petroleum gas network, with 459 plants in 2015 creating 1.2 billion m3 and 340 plants taking care of into the gas network, with a limit of 1.5 million m3. Around 697 biomethane filling stations guaranteed the utilization 160 million m3 of biomethane as a transport fuel in 2015.

Evaluación de la diversidad taxonómica y funcional de la comunidad microbiana relacionada con el ciclo del nitrógeno en suelos de cultivo de arroz con diferentes manejos del tamo

Abstract: La quema del tamo de arroz a campo abierto es una de las mayores fuentes de contaminacion agricola, es por esto que el retorno de los residuos vegetales al suelo ha sido propuesto como una alternativa de manejo eficiente de los residuos pos-cosecha. Sin embargo, es poco conocido el impacto que tiene sobre los microorganismos edaficos involucrados en la disponibilidad y ciclaje de nutrientes. Por lo anterior, se planteo un experimento en campo para evaluar los cambios generados sobre la comunidad microbiana vinculada al ciclo del nitrogeno por la aplicacion de 4 tratamientos diferentes de manejo del tamo de arroz: (Cob+mo) cobertura del terreno con tamo de arroz inoculado con un consorcio microbiano de degradacion, (Inc+mo) tamo de arroz inoculado con el consorcio microbiano e incorporado, (Quema) quema del tamo y (Cob) cobertura del terreno con tamo de arroz sin inocular. Se realizaron 4 muestreos de suelo de soporte y suelo rizosferico antes y durante el ciclo de cultivo. Se evaluo la diversidad, estructura y composicion de la comunidad bacteriana a traves del analisis del gen 16S rRNA y se determino la actividad de las enzimas nitrogenasa, proteasa y ureasa vinculadas con el ingreso de nitrogeno al sistema edafico. Al final del ciclo de cultivo, los mapas de calor basados en la composicion y abundancia de especies, mostraron que las comunidades microbianas de los tratamientos alternos a la quema son mas similares entre si, indicando que la adicion de materia organica influencia la comunidad edafica microbiana. La actividad de las enzimas proteasa y ureasa se vio afectada por la aplicacion del consorcio de degradacion y la forma de retorno del tamo de arroz al suelo respectivamente. Palabras clave: (Incorporacion, cobertura, tamo de arroz, actividad enzimatica, 16S rRNA).

Lipase from Thermomyces lanuginosus: Uses and prospects as an industrial biocatalyst

Abstract: The lipase from Thermomyces laguginosus (formerly Humicola laguginosa) (TLL) is a basophilic and noticeably thermostable enzyme, commercially available in both soluble and immobilized form. Although initially oriented toward the food industry, the enzyme has found applications in many different industrial areas, from biodiesel production to fine chemicals (mainly in enantio and regioselective or specific processes). This review intends to show some of the most relevant aspects of the use of this interesting enzyme. After checking the enzyme features, some of the most efficient methods of TLL immobilization will be commented. Finally, the main uses of the enzyme will be revised, with special emphasis in the modification of fats and oils, production of biodiesel, resolution of racemic mixtures, enantioselective hydrolysis of prochiral esters and regioselective process involving sugar preparations. In many instances, TLL has been compared to other lipases, the advantages or disadvantages of the enzyme will be discussed.