Page 23 - mobile Workbook-chapter 2

QUESTIONS - EXERCISES

Q1. Explain the difference between fixed carbon and volatile matter.

Q2. List three methods for determining the energy content of the organic components in MSW.

Which method most accurately reflects ‘real-world’ energy production?
Q3. Explain fluctuations in waste composition are affected by both geographic region & season

of the year.
Q4. What factors must be considered when evaluating MSW as a potential fuel?

Q5. Why are lignin and cellulose only slowly biodegradable? Refer to their chemical structures.
Q6. How does the total moisture content affect overall management of MSW?

Are there environmental or other implications to a high-moisture content waste stream?

Q7. Define: heat value, putrescible.
E1. Estimate the chemical formula of the organic fraction of a sample of MSW. Some data on

waste properties is shown below:

Components Wet weight Dry weight % by wt of dry basis
(kg) (kg) C H O N S Ash

Paper 19.00 16.00 43.5 6.0 44.0 0.3 0.20 6.0

Plastics 3.70 3.50 60.0 7.2 22.8 - - 10.0
Food wastes 5.10 1.90 48.0 6.4 37.6 2.6 0.40 5.0

Yard wastes 8.40 2.60 47.8 6.0 38.0 3.4 0.30 4.5
Textiles 1.00 0.80 55.0 6.6 31.2 4.6 0.15 2.5

Rubber 0.22 0.22 78.0 10.0 - 2.0 - 10.0
Wood 1.30 0.90 49.5 6.0 42.7 0.2 0.1 1.5

Determine heat value (LHV) by applying the modified Dulong’ equation.

E2. Estimate the chemical composition of the organic fraction of the MSW sample described
in the below table and calculate the heat content using the modified Dulong’ equation.

Components Wet weight (kg) Dry weight (kg)

Food wastes 19.00 16.00
Yard wastes 3.70 3.50

Paper 5.10 1.90
Plastics 8.40 2.60

Notice: Refer %by wt of dry basis of major elements following the table in E1

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