Municipal Solid Wastes (MSW)

Environmental Engineering · FE Reference Handbook section

Environmental Engineering

0 formulas

10 exam-style examples

~45 min

All Environmental Engineering lectures

Handbook notes for this section

Definitions and conditions exactly as the handbook states them.

Typical Heating Value of MSW Components
Tchobanoglous, George, Hilary Theisen, and Rolf Eliassen, Solid Wastes: Engineering Principles and Management Issues, New York: McGraw-Hill, 1977, p. 62.

Core formulas for this FE topic

Definitions, applicability, units, assumptions and worked examples for each relation.

This section is conceptual; there are no equations to memorise.

Worked exam-style examples

The four ways this section is written on the real exam — thoughts first, then equations, then substitution.

Example 1

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW)

A community of 192,515 people generates 2.1 kg/person/day of MSW and diverts 20% through recycling. Compacted in place at 517 kg/m³ with 25% additional daily cover volume, find the airspace needed for 29 years.

Given

$Population = 192,515$
$Generation = 2.1 kg/cap/d$
$Diversion = 0.20$
$Compacted density = 517 kg/m^{3}$
$Cover = 25%, design life 29 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$192515(2.1)(1 - 0.20) = 323,425 kg/day$
Formula
$V = mass/density$
Substituting
$V = 323,425/517 = 625.6 m^{3}/day$
Annual with cover
$625.6 \times 365 \times 1.25 = 285,421 m^{3}/yr$
Design life
$285,421 \times 29 = 8,277,214 m^{3}$

Answer:

≈ 285,421 m³/yr, or 8,277,214 m³ over 29 years

Why the other options are there

8,277,214 m³ (diversion and cover ignored)
3,423,455,742 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 2

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (2)

A community of 149,338 people generates 2.9 kg/person/day of MSW and diverts 25% through recycling. Compacted in place at 716 kg/m³ with 10% additional daily cover volume, find the airspace needed for 17 years.

Given

$Population = 149,338$
$Generation = 2.9 kg/cap/d$
$Diversion = 0.25$
$Compacted density = 716 kg/m^{3}$
$Cover = 10%, design life 17 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$149338(2.9)(1 - 0.25) = 324,810 kg/day$
Formula
$V = mass/density$
Substituting
$V = 324,810/716 = 453.6 m^{3}/day$
Annual with cover
$453.6 \times 365 \times 1.10 = 182,139 m^{3}/yr$
Design life
$182,139 \times 17 = 3,096,357 m^{3}$

Answer:

≈ 182,139 m³/yr, or 3,096,357 m³ over 17 years

Why the other options are there

3,753,160 m³ (diversion and cover ignored)
2,015,446,981 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 3

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (3)

A community of 141,833 people generates 2.4 kg/person/day of MSW and diverts 25% through recycling. Compacted in place at 590 kg/m³ with 10% additional daily cover volume, find the airspace needed for 30 years.

Given

$Population = 141,833$
$Generation = 2.4 kg/cap/d$
$Diversion = 0.25$
$Compacted density = 590 kg/m^{3}$
$Cover = 10%, design life 30 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$141833(2.4)(1 - 0.25) = 255,299 kg/day$
Formula
$V = mass/density$
Substituting
$V = 255,299/590 = 432.7 m^{3}/day$
Annual with cover
$432.7 \times 365 \times 1.10 = 173,733 m^{3}/yr$
Design life
$173,733 \times 30 = 5,212,002 m^{3}$

Answer:

≈ 173,733 m³/yr, or 5,212,002 m³ over 30 years

Why the other options are there

6,317,578 m³ (diversion and cover ignored)
2,795,528,430 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 4

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (4)

A community of 66,768 people generates 2.9 kg/person/day of MSW and diverts 20% through recycling. Compacted in place at 567 kg/m³ with 10% additional daily cover volume, find the airspace needed for 18 years.

Given

$Population = 66,768$
$Generation = 2.9 kg/cap/d$
$Diversion = 0.20$
$Compacted density = 567 kg/m^{3}$
$Cover = 10%, design life 18 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$66768(2.9)(1 - 0.20) = 154,902 kg/day$
Formula
$V = mass/density$
Substituting
$V = 154,902/567 = 273.2 m^{3}/day$
Annual with cover
$273.2 \times 365 \times 1.10 = 109,688 m^{3}/yr$
Design life
$109,688 \times 18 = 1,974,383 m^{3}$

Answer:

≈ 109,688 m³/yr, or 1,974,383 m³ over 18 years

Why the other options are there

2,243,617 m³ (diversion and cover ignored)
1,017,704,563 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 5

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (5)

A community of 49,256 people generates 2.4 kg/person/day of MSW and diverts 35% through recycling. Compacted in place at 850 kg/m³ with 15% additional daily cover volume, find the airspace needed for 24 years.

Given

$Population = 49,256$
$Generation = 2.4 kg/cap/d$
$Diversion = 0.35$
$Compacted density = 850 kg/m^{3}$
$Cover = 15%, design life 24 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$49256(2.4)(1 - 0.35) = 76,839 kg/day$
Formula
$V = mass/density$
Substituting
$V = 76,839/850 = 90.4 m^{3}/day$
Annual with cover
$90.4 \times 365 \times 1.15 = 37,945 m^{3}/yr$
Design life
$37,945 \times 24 = 910,682 m^{3}$

Answer:

≈ 37,945 m³/yr, or 910,682 m³ over 24 years

Why the other options are there

1,218,304 m³ (diversion and cover ignored)
673,112,794 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 6

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (6)

A community of 188,271 people generates 2.6 kg/person/day of MSW and diverts 25% through recycling. Compacted in place at 712 kg/m³ with 20% additional daily cover volume, find the airspace needed for 13 years.

Given

$Population = 188,271$
$Generation = 2.6 kg/cap/d$
$Diversion = 0.25$
$Compacted density = 712 kg/m^{3}$
$Cover = 20%, design life 13 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$188271(2.6)(1 - 0.25) = 367,128 kg/day$
Formula
$V = mass/density$
Substituting
$V = 367,128/712 = 515.6 m^{3}/day$
Annual with cover
$515.6 \times 365 \times 1.20 = 225,846 m^{3}/yr$
Design life
$225,846 \times 13 = 2,935,996 m^{3}$

Answer:

≈ 225,846 m³/yr, or 2,935,996 m³ over 13 years

Why the other options are there

3,262,218 m³ (diversion and cover ignored)
1,742,024,495 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 7

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (7)

A community of 167,011 people generates 2.8 kg/person/day of MSW and diverts 15% through recycling. Compacted in place at 629 kg/m³ with 10% additional daily cover volume, find the airspace needed for 13 years.

Given

$Population = 167,011$
$Generation = 2.8 kg/cap/d$
$Diversion = 0.15$
$Compacted density = 629 kg/m^{3}$
$Cover = 10%, design life 13 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$167011(2.8)(1 - 0.15) = 397,486 kg/day$
Formula
$V = mass/density$
Substituting
$V = 397,486/629 = 631.9 m^{3}/day$
Annual with cover
$631.9 \times 365 \times 1.10 = 253,721 m^{3}/yr$
Design life
$253,721 \times 13 = 3,298,377 m^{3}$

Answer:

≈ 253,721 m³/yr, or 3,298,377 m³ over 13 years

Why the other options are there

3,527,676 m³ (diversion and cover ignored)
1,886,071,924 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 8

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (8)

A community of 177,612 people generates 2.7 kg/person/day of MSW and diverts 35% through recycling. Compacted in place at 726 kg/m³ with 20% additional daily cover volume, find the airspace needed for 14 years.

Given

$Population = 177,612$
$Generation = 2.7 kg/cap/d$
$Diversion = 0.35$
$Compacted density = 726 kg/m^{3}$
$Cover = 20%, design life 14 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$177612(2.7)(1 - 0.35) = 311,709 kg/day$
Formula
$V = mass/density$
Substituting
$V = 311,709/726 = 429.4 m^{3}/day$
Annual with cover
$429.4 \times 365 \times 1.20 = 188,056 m^{3}/yr$
Design life
$188,056 \times 14 = 2,632,782 m^{3}$

Answer:

≈ 188,056 m³/yr, or 2,632,782 m³ over 14 years

Why the other options are there

3,375,362 m³ (diversion and cover ignored)
1,592,833,297 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 9

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (9)

A community of 103,821 people generates 2.3 kg/person/day of MSW and diverts 40% through recycling. Compacted in place at 539 kg/m³ with 15% additional daily cover volume, find the airspace needed for 29 years.

Given

$Population = 103,821$
$Generation = 2.3 kg/cap/d$
$Diversion = 0.40$
$Compacted density = 539 kg/m^{3}$
$Cover = 15%, design life 29 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$103821(2.3)(1 - 0.40) = 143,273 kg/day$
Formula
$V = mass/density$
Substituting
$V = 143,273/539 = 265.8 m^{3}/day$
Annual with cover
$265.8 \times 365 \times 1.15 = 111,575 m^{3}/yr$
Design life
$111,575 \times 29 = 3,235,670 m^{3}$

Answer:

≈ 111,575 m³/yr, or 3,235,670 m³ over 29 years

Why the other options are there

4,689,377 m³ (diversion and cover ignored)
1,516,544,493 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)

Example 10

Landfill volume required for a community's solid waste — Municipal Solid Wastes (MSW) (10)

A community of 155,376 people generates 2.2 kg/person/day of MSW and diverts 20% through recycling. Compacted in place at 665 kg/m³ with 25% additional daily cover volume, find the airspace needed for 18 years.

Given

$Population = 155,376$
$Generation = 2.2 kg/cap/d$
$Diversion = 0.20$
$Compacted density = 665 kg/m^{3}$
$Cover = 25%, design life 18 yr$

Find

Annual and total landfill airspace

Start with the thinking

Only the landfilled fraction consumes airspace — diverted material is subtracted first.
Daily cover soil is real volume and must be added to the waste volume.

Step-by-step solution

Formula
$landfilled mass = population \times rate \times (1 - diversion)$
Substituting
$155376(2.2)(1 - 0.20) = 273,462 kg/day$
Formula
$V = mass/density$
Substituting
$V = 273,462/665 = 411.2 m^{3}/day$
Annual with cover
$411.2 \times 365 \times 1.25 = 187,619 m^{3}/yr$
Design life
$187,619 \times 18 = 3,377,150 m^{3}$

Answer:

≈ 187,619 m³/yr, or 3,377,150 m³ over 18 years

Why the other options are there

3,377,150 m³ (diversion and cover ignored)
1,796,643,763 m³ (mass reported as volume)

Reference: FE Reference Handbook — Environmental Engineering → Municipal Solid Wastes (MSW)