Question

A landfill is to be designed to serve a population of 200000 for a period of 25 years. The solid waste (SW) generation is 2 kg/person/day. The density of the un-compacted SW is 100 kg/m³ and a compaction ratio of 4 is suggested. The ratio of compacted fill (i.e., SW + cover) to compacted SW is 1.5. The landfill volume (in million m³) required is____________.

Answer 1

Concept:

\({\rm{CompactionRatio = }}\frac{{{\rm{Volume}}\;{\rm{before}}\;{\rm{compaction}}}}{{{\rm{Volume}}\;{\rm{after}}\;{\rm{compaction}}}}\)

Total Volume = SW + Cover

Calculation:

Solid waste generated per day= 2 × 200000 = 400000 kg

Total solid waste generated in 25 years = 400000 × 365 × 25 = 3.65 × 10⁹ kg

Compaction ratio,

\(4 = \frac{{{\rm{Volume\;before\;compaction}}}}{{{\rm{Volume\;after\;compaction}}}}\)

Volume of waste before compaction,

\({\rm{V}} = \frac{{3.65 \times {{10}^9}}}{{100}} = 3.65 \times {10^7}\ {{\rm{m}}^3}\)

Volume of waste after compaction,

\(\begin{array}{l} {\rm{V'}} = \frac{{3.65 \times {{10}^9}}}{{100\times 4}} = 9.125 \times {10^6}\ {{\rm{m}}^3}\\ \frac{{{\rm{SW}} + {\rm{cover}}}}{{{\rm{SW}}}} = \frac{{{\rm{SW}}}}{{{\rm{SW}}}} + \frac{{{\rm{cover}}}}{{{\rm{SW}}}} = 1.5\\ \frac{{{\rm{Cover}}}}{{{\rm{SW}}}} = 0.5 \end{array}\)

Cover = 0.5 × 9.125 × 10⁶

Cover = 4.5625 × 10⁶ m³

Total Volume = SW + Cover

Total Volume = (9.125 + 4.5625) × 10⁶ m³

Total Volume = 13.6875 million m³