MUHAMMAD FAHAD ANSARI 12IEEM 14

Crop Residues UtilisationCrop Residues Utilisation

What are Crop Residues?Crop residues, also referred to as "agricultural waste," non-photosynthetic vegetation or "farm residue," and are comprised of stalks, cobs, and other plant parts left behind after harvesting the crop/crops on the farm they were grown at.

Why are Crop Residues important?According to the U.S. Department of Agriculture, crop residues are important because:When left on the soil's surface, crop residues;

–  Protect the soil from wind and water erosion.–  Reduce evaporation by acting as a mulch.–  Their breakdown helps sequester carbon emissions into the soil.-  This also recycles nutrients.–  Improve the soil's structure and its water retention capabilities.

When removed from the soil, crop residues:

–  Do not benefit the soil, but can be used for cellulosic ethanol biofuels as well as an excellent biomass feedstock for generating "carbon free energy" through the production of Synthesis Gas from a Biomass Gasification plant.Biomass supply from crop residues can increase a producer's profits while maintaining the farm's soil quality as long as the farm's reduced tillage and partial residue harvest are used appropriately. The Corn Belt, Great Plains, and West Coast's use of crop residues as a biomass feedstock is possible with judicious selection of crops and crop management practices. Crop residues are probably the lowest cost form of biomass supply, but the range of costs is wider in the Great Plains than in the Corn Belt. The remaining regions, including the West Coast, the Delta, and the Southeast, also have pockets with crop residue supplies and a wide variation in costs.Crop residues have the potential to displace 12.5 percent of petroleum imports or 5 percent of electricity consumption in today’s markets. Crop residues also have growth potential from improving crop productivity and declining livestock demands for forage. When crop residues (as a biomass feedstock) are included with some other agricultural sources, biomass supply from crop agriculture could account for more than 100% of the fuel requirements for our country's electricity requirementshrough the production of Synthesis Gas from a Biomass Gasification plant.  

What is "waste to clean energy"?Waste to Clean Energy, better known as Waste to Energy, are operations and facilities that produce clean, renewable energy through the combustion of municipal solid waste in specially designed power plants equipped with the most modern pollution control equipment to clean emissions. Trash volume is reduced by 90% and the remaining residue is regularly tested and consistently meets strict EPA standards allowing reuse or disposal in landfills. There are 89 waste-to-energy plants operating in 27 states managing about 13 percent of America's trash, or about 95,000 tons each day. Waste to Energy facilities generate about 2,500 megawatts of electricity to meet the power needs of nearly 2.3 million homes, and the facilities serve the trash disposal needs of more than 36 million people. The $10 billion Waste to Energy industry already employs more than 7,000 American workers with annual wages in excess of $400 million.

Estimates of Crop Residues Estimates of Crop Residues Production in the U.S.Production in the U.S.

Species 1991 2001

- - - - - - 106 Mg - - - - - -

Cereals 325 367`

Legumes 58 82

Oil Crops 17 20

Sugar Crops 25 14

Tubers 5 5

Total 430 488(Lal, 2005)(Lal, 2005)

Estimates of Crop Residues Estimates of Crop Residues Production in the WorldProduction in the World

Species 1991 2001

- - - - - - 106 Mg - - - - - -

Cereals 2563 2802

Legumes 238 305

Oil Crops 162 108

Sugar Crops 340 373

Tubers 145 170

Total 3448 3758(Lal, 2005)(Lal, 2005)

Crop Residue and Ecosystem Services

Biofuel

Traditional

Modern Liquid Biofuels

Animal Feed

Industrial Raw Material

Soil Quality Improvement

Agr

onom

ic/B

iom

ass

Pro

duct

ivit

y an

d Su

stai

nab

ilit

y

Erosion Control

Nutrient Cycling

Soil Biodiversity

Water Management

Soil Structure & Tilth

Carbon Sequestration

1. Crop residues have numerous competing uses, such as removal for biofuel production, animal feed, industrial raw material or returned to soil as an amendment.

2. Soil application of crop residues as amendment is necessary to enhance/maintain soil quality and sustain agronomic productivity.

Competing Uses of Crop Competing Uses of Crop ResiduesResidues

• Feed

• Fuel

• Fiber

• Construction material

Slope-Soil Loss Relations for Slope-Soil Loss Relations for Different Mulch Rates (Lal, 1976)Different Mulch Rates (Lal, 1976)

Mulch Rate

r Equation Average (Mg/ha)

Relative Loss

0 0.81 Y = 11.8 S1.13 76.60 851

2 0.35 Y = 0.5 S0.87 2.40 27

4 0.57 Y = 0.07 S1.05 0.37 4

6 0.46 Y = 0.01 S1.0 0.09 1

No-till 0.36 Y = 0.01 S0.5 0.09 1

Energy in BiomassEnergy in Biomass

One Mg of Corn Stover =

• 280 L of Ethanol

• 15 - 18 GJ of Energy

• 16 x 106 BTU

• 2 Barrels of Diesel

• 3 x 106 KCal

(Lal, 2005)

Estimates of Traditional Biofuel Use Estimates of Traditional Biofuel Use in India and Asia in 1995in India and Asia in 1995

Country/Region

Fuel wood Cattle Dung

Crop Residue

Total

Range Average

- - - - - - - - - - - - - - Tg C yr-1 - - - - - - - - - - - - - - -

India 109 - 409 35 - 108 20 - 67 164 - 584 374

Asia 800 - 930 130 - 200 430 - 565 1360 - 1675 1018

World 1324 - 1615 150 - 410 442 - 707 1916 - 2732 2324

Biofuel From Industrial CO2

and SOC Sequestration

Ethanol

Biodiesel

Biochemicals

Nutrient-Enriched &

Biochar/Compost

Residues

Bioreactors

Soil Carbon Sequestration

Algae

Cynobacteria

Algae

Cynobacteria

Ap

pli

cati

on

on

Ag

. S

oil

s

Bioenergy

Strategic QuestionsStrategic Questions

• Should crop residues be used for carbon sequestration and soil quality improvement or producing energy?

• Should the answer to this question be determined by short-term economics or the long-term sustainability of natural resources?

• Should the need for fuel override the urgency to achieve global food security?