Effenberger- the limits of biomass & bioenergy; Overview of (conventional) biomass process chains

Question 1

Definition of NPP?

Answer 1

Net primary production, NPP:

Amount of plant biomass that grows within a year in a given area, neglecting emissions of VOC and root exudates as well as above- and below-ground litter recycled within a year.

NPP₀ :

NPP in the absence of human interventions such as fertilization, irrigation or soil sealing (“natural NPP”).

Human appropriation of NPP, HANPP

= NPP₀ – (fraction of NPP left after human use)

Question 2

What are the limits on bioenergy potential?

Answer 2

• Future bioenergy potential is limited and
• strongly dependent on future diets.
• Roughage demand of livestock on grazing areas has a

significant effect on bioenergy potential.

• For ‚business-as-usual‘: Bioenergy potential from cropland

and grazing land ≈ 100 EJ y-1

–> Integrated optimization of food, fiber and bioenergy supply (‚biorefineries‘)

–> Area demand of bioenergy highly important

–> Environmental issues of bioenergy, particularly energy crops need to be evaluated carefully.

Question 3

Give the steps of conventional biomass process chain!

Answer 3

1. Land use
2. Treatment & Conversion
3. Utilization
4. Recycling / Disposal

Question 4

What are biorefineries?

Answer 4

Integrative process concepts, to inforce the cascaded refinement of renewable raw materials into bio-based products (materials, basic chemicals etc.) and biogenic energy carriers (fuels, electricity and heat).

–>Extension of established processes with the aim of: „preferably complete utilization of

all inputs and outputs.

Question 5

What are the base material for biorefineries?

Answer 5

Base material:

Various renewable raw materials (RRM) with four basic structures:

– Saccharides / poly-saccharide (sugar, starch, cellulose, hemi-cellulose)

– Polyphenols (Lignin)

– Tri-glycerides und Lipids (plant oils and animal fat)

– Proteins

Established processes with direct physical conversion:

– e.g., paper mills, starch / sugar factories, oil mills

Established processes with biotechnological conversion

(microbial / enzymatic):

– Production of alcohols, fatty acids, biologically degradable polymers

Question 6

Draw the schematic representation of biorefinery

Answer 6

Platforms could be: C5 Sugars, C6 Sugars, Oils, Biogas, Syngas, Hydrogen, Organic Juice, Pyrolytic Liquid, Electricity and Heat

Products could be:

Energy products: Bio-diesel/ -ethanol/-methane, Synthetic biofuels, Elec&Heat

Material products: Food, Animal Feed, Fertilizer, Glycerin, Biomaterials, Chemicals and building blocks, Polymers and resins, Biohydrogen

Feedstocks:

Crops: Sugar, Oil, Starch, Lignocellulosic, Grasses, Marine Biomass

_Residues: o_f all above crops

Processes:

Thermochemical: Combustion/Gasification/Hydrothermal upgrading/ Pyrolysis/Supercritical

Biochemical: Fermentation/ An/ aerobic Digestion/ Enzymatic processes/

Chemical: Many: esterification, methanization, steam reforming, waer gas shift, hydrolysis, hydrogenation, pulping…

Mechanical/Physical: Extraction, Fiber separation, Mechanical fractionation, pressing/disruption

Question 7

Give Five promising biorefinery concepts:

Answer 7

● Sugar-Biorefinery / Starch-Biorefinery

● Plant Oil-Biorefinery / Algal Lipid-Biorefinery

● Lignocellulose (Cellulose, Hemicellulose and Lignin)-Biorefinery / Green Biorefinery

● Synthesis Gas-Biorefinery

● Biogas-Biorefinery

Question 8

Pathways for lignocellulosic residues

Question 9

Pathways for grass biomass

Question 10

What is Bioeconomy?

Answer 10

„Bioeconomy is the knowledge-based production and use of biological resources to provide products, processes and services in all economic sectors within the frame of a sustainable economic system.”

Bio-based economy

–> Rising prices of fossil fuels

–>Climate change & associated economic risks

–>Sustainable development

–>Long-term economic competitiveness

Question 11

Taking the „right“ path to the bioeconomy, How and how fast?

Answer 11

1. Bioenergy: Energy storage rather than energy generation
2. Biomass:

Refrain from high national expansion targets

Refrain from promoting expansion with subsidies

3. Increase Efficiency
   reduce ecological footprint and per capita consumption

Question 12

What are the key points for a Market for renewable raw materials (RRM)

Answer 12

• Substitution of fossil resources

–> Mitigate global warming

–> Improve supply security

–>Increase added value in rural areas and secure farmers‘ incomes

• Improve efficiency of RRM utilization
• Increase share of RRM for

primary energy and material supply in Germany

• EC views biomass-based products as one of the six most

promising future markets

Question 13

What are the incentives for bio-based economy?

Answer 13

2009:

EU Renewable Energy Directive (RED) –>2020 Meet 20 % of the EU‘s overall energy demand (“gross final energy consumption”) from renewable sources, with a minimum of 10 % for transport demand!

2016:

RED II proposal –> 2030 Meet 27 % of the EU’s overall energy demand from

renewable sources!

Question 14

Difference between RED and RED II ?

Answer 14

“To prepare for the transition towards advanced biofuels and minimise the overall indirect land-use change impacts, it is appropriate to reduce the amount of biofuels and bioliquids produced from food and feed crops (…).

Assessment of RED II: „Low-emission fuels“

• Advanced biofuels= „biofuels that are produced from feedstocks listed in part A of Annex IX“ Includes feedstocks used by the chemical and materials industries over a long time to process them into high-value materials.
• Renewable liquid and gaseous transport fuels of non-biological origin= Fuels other than biofuels whose energy content comes from RES other than biomass, most commonly: hydrogen from renewable electricity. –> CO2 may stem from both fossil and biogenic sources
• Waste-based fossil fuels = liquid and gaseous fuels produced from waste streams of non-renewable origin, including waste processing gases and exhaust gases
• Renewable electricity

Question 15

What is Direct land use change (dLUC):? Indirect land use change (iLUC):? Total LUC?

Answer 15

dLUC

Antropogenic change in land use within the boundaries of the system assessed.

(iLUC):

Change in land use as a consequence of dLUC, but outside the system boundaries.

Total LUC = (dLUC + iLUC)

Question 16

With technology to choose best for waste treatment?

Question 17

Goal of LCA for Energy from Biogas?

Answer 17

Aim:

Assessment of environmental impacts from combined electricity and heat production in an agricultural biogas plant

Functional unit:

One kilowatt hour electrical energy (kWh)

Question 18

Which RES has the highest acidification impact of electricity?

Answer 18

Question 19

Which RES has the highest GW impact of electricity?

Question 20

Draw a SWOT Analysis of Biogas from Agricultural crops!

Answer 20

Question 21

Draw a SWOT Analysis of RRM from Agricultural crops!

Answer 21