15 September 2021, 9:30 PM

The purpose of this journal is to explore and understand the course MKKE2163-01-02 Biojisim Bagi Tenaga Diperbaharui, Bahan Api Dan Bahan Kimia (Biomass For Renewable Energy, Fuels And Chemicals). Gained knowledge from the class and identify how it can be derived to real operating condition. Most modern topics of the biomass system are delivered. Combustion system, gasification, anaerobic fermentation, ethanol, and steam rankine cycle are observed as component to be practise in commercial. Biorefinery is an essential technology for biomass development. Depend on individual’s experiences, the suggestions and understandings are indicated in this journal. Finance risk assessment is priority to make a change to overcome the less intention of investor and developer and associated problems. The expansion of development of second-generation and third generation of Biofuel is needed to be deploy constantly.

CHAPTER 1 


CONTENT

1.1            Biomass Conversion

Biomass conversion involved a) thermal conversion (Pyrolysis, Combustion – co-firing, Gasification), b) biological conversion (Fermentation, Digestion), c) Mechanical conversion.

1.2            Direct Combustion

In a combined heat and power unit, after feedstock processing, the fuel is fed to the combustion system. Here, the term combustion system encompasses the combustion chamber and boiler where steam generation occurs. Combustion occurs when fuel-bound carbon reacts with an oxidant (oxygen gas, in this case). General processes are drying, degasification, gasification, and combustion. Steam turbine Combined Heat and Power (CHP), type of boiler and grate technology are discussed. Gas turbine Combined Heat and Power, Anaerobic Digestion, electrical efficiency is gained.

1.3            Pyrolysis & Gasification

Biomass is being heated, absence of the oxygen, decompose into char, gaseous product, and liquid product. Fast and Flash pyrolysis are used widely in bio-oil industry. Gasification mainly produce syngas and it can be used to produce electricity, heat and power, liquid fuels, and synthetic chemicals.

1.4            Oxygenated Liquid Fuel

Classify three-generation biofuels, first biofuel is edible parts of agricultural, second biofuel is non-edible of agricultural crops and wastes. Third-generation biofuel is come from algae, and it is also promised by higher yield. Biofuel includes biodiesel, green diesel, FT renewable diesel, tailor-made green diesel, all of them are designed depend on the blending. Biodegradable, promising product to reduce emission.

1.5            Biogas Production from Biomass

Biogas is a mixture of gas, which consist of methane (CH4), Carbon dioxide (CO2), Nitrogen (N2), Hydrogen sulfide (H2S) and a little of hydrogen (H2), Oxygen (O2), and Carbon oxide (CO). The amount of biogas (methane and carbon dioxide) content is quantified by water and solid content of the wet waste/feedstock by using chemical oxygen demand concept.

1.6            Biorefinery

An international policy, IEA bioenergy Task 42 Biorefineries, coproducing fuels, chemicals, power, and materials from biomass. Centralised bioenergy of the world in one place. To become more efficiency. Important rules are established and it is useful and informative for biomass designer

CHAPTER 2  


ANALYSIS AND EVALUATION

2.1            Combustion system

Currently, the primary approach for biomass conversion to electricity is also the most time-tested and high maturity: combustion. The efficiency of the combustion system as specific main inputs is moisture content, the biomass feedstock handling option, combustion system type, percent excess fed air, flue gas temperature, number of boilers, steam grade, and boiler overdesign factor. Combustor’s selection is an essential. Fluidized bed combustion, bubbling fluidized bed (BFB), circulating fluidized bed (CFB) are the mainstream combustion technologies, depend on how big the capacity (MW) is, and the type of feedstock, and the owner’s investment criteria. Energy balance is relied on the overall heating value of the fuels. Mass balance is also needed to consider at biomass stream and boiler steam stream.

2.2            Gasification

Combustible gas has been to replace fuel oil in industrial boilers, furnaces, and kilns. Production gas has generally been successful in direct heating applications because the gasifiers can be closely coupled to the gas burner/reactor, thereby eliminating tar condensation. Used for cooking of household and service sector. For electricity or shaft power generation, such as internal combustion engine, either diesel or gasoline engine. Reduced air pollutant emissions compared to diesel-fueled engine. Reduced particulate emissions compared to direct burning of solid fuel. The concerns are waste-water cleanup and clean combustion.

2.3            Anaerobic Fermentation

In an anaerobic digester, organic matter is degraded by three kinds of bacteria: fermentative bacteria, acetogens, and methanogens. The first two break down complex organic compounds into simpler intermediates, which are then converted to methane and carbon dioxide by the methanogens. Biogas is used widely in Mainland, China, and the major biogas producing from animal manure. Cooking gas, electricity, fuel gas for energy service for household, and industry. The environment concerns are incomplete pathogen destruction, and insufficient emissions reduction.

2.4            Steam Rankine Cycle

A biomass plant is reported as operation in year 2007 which located in Bentong, Pahang. The plant is fired with empty fruits bunched and industry waste from nearby industry. The biomass plant produce steam and sold to the nearby paper factory. Many existing biomass power plants use a combined heat and power approach, meaning that some of the boiler steam is directly used in industrial processes rather than generating electricity. The efficiency fluctuates based on the ambient air temperature, as well as on the part load (or fraction of capacity) at which the turbine operates. Turbines generally do not operate below a certain fraction of full load since turbine performance is difficult to predict and the economics may become unfavorable.

2.5            Ethanol

Clean liquid transportation fuel, a lot of investors prefer to this development of fuel ethanol, especially from sugarcane. Reduced urban air pollution from vehicles, highly favorable energy output to input ratio. The concerns are burning of cane fields and soil degradation.

CHAPTER 3  


SUGGESTIONS

3.1            Potential Improvements

1. R&D development such Anaerobic digester, tools, equipment and land (feedstock) should be put more efforts.
2. Local regulations and policy should be kept up to date, based on the track record and big data from the local authorities.
3. Subsidies for biomass scheme should be upgraded based on the current global energy transition.
4. New financial criteria for biomass project should be evaluated to have more cost-effective.
5. Individual awareness on the crisis of climate change should be enhanced to have more quality education

CHAPTER 4  


REFLECTION

4.1            Learning Issues

In term of social-economic point of view, individual income is affected by the pandemic and influence of unstable self-management. Therefore, self-mentality is affected as well. The intent or willing abilities either, learning have impacted on personal self-discipline. Time management is essential for learning deployment. Individual’s personality should be a concern for professional development.