Bioenergy II Flashcards
Biomass can be converted into energy via various processes . Name these processes.
Combustion, dry chemical combustion and aqueous processes.
What do you know about biomass energy conversion through combustion.
The fuel can be converted straight into electricity.
What do you know about biomass energy conversion through dry chemical combustion.
Can be done through three main ways and each way has different end products.
Path 1: pyrolysis :end products are oils , char and gas
Path 2: gasification:end products are low medium energy gas which can be converted into methane, methanol,ammonia.
Path 3: hydro gasification : end products are char methane and ethane .
What do you know about biomass energy conversion through aqueous processes.
Also has 3 paths all with different end products
Path 1: chemical reduction: end product is oils
Path 2: alcoholic fermentation:end product is ethanol
Path 3: anaerobic digestion end product is methane.
Is this statement true or false:biodiesel consumption in the USA has been on the rise since 2010.
True
How does use of biofuels in Sweden look like?
Biofuel use has been on an upward trajectory. With almost a third of the transport consumption coming from biofuels.
The dominant ones are biodiesel, biogas and ethanol.
What are some of the most used biodiesels?
Fatty acids methyl ester (FAME): Mostly made from rape seed oil.
Hydrotreated vegetable oil (HVO) made from animal fat, rape seed oil, pine oil (from pulp and paper industry).
What is effective heat value ?
This refers to the amount of heat energy released during combustion of a substance.
This heat value is dependent on moisture content. The higher the moisture content the lower the effective heat value because it will require extra energy to dry out moisture before combustion. This will also lead to increased emissions.
What is the correlation between ash,dry mass content and moisture content?
The higher the moisture content the lower the ash, dry matter content is in fuels
Strange fact about oxygen in fuels and emissions
Although oxygen is necessary for efficient combustion, the higher the oxygen content in fuel is the more emissions are released.this is because it decreases the heat value.
Hydrogen to carbon H/C ratios and oxygen to carbon ratios (O/C) ratios.
The higher the O/C ratios the higher the emissions the higher the H/C ratios the lower the emissions
Recycling of CO2, what is it about ?
This happens when emitted from cars etc are captured by plants used for photosynthesis to produce biomass and then used in the production of bioenergy and biomaterials to be distributed.
What is the correlation between Bioenergy and low sulfur emissions ?
Bioenergy has lower sulfur content than fossil fuels . It is how ever important to note that fuel oil 1 has the lowest sulfur content of all fuels because it is purposefully removed.
What are the steps involved in methanol production from coal/biomass?
Storage and pretreatment,gasification,particle removal,gas wash, gas shift, desulfurization, methanol synthesis, methanol.
PGGwGsDesMethsyn
Gasification it self has a set of 4 steps
Drying and heat , pyrolysis,reduction zone ,combustion . The temperature increases as you go down . And during pyrolysis (no air in this step)if pressure is increased you get lower charcoal .
DPPRC
