Raw municipal solid waste (MSW) collected from a city contains 70% decomposable material that can be converted to methane. The water content of the decomposable material is 35%

Q. Raw municipal solid waste (MSW) collected from a city contains 70% decomposable material that can be converted to methane. The water content of the decomposable material is 35%. An elemental analysis of the decomposable material yields the following mass percent.

C : H : O : N : other = 44 : 6 : 43 : 0.8 : 6.2

The methane production of the decomposable material is governed by the following stoichiometric relation

CaHbOcNd + nH2O → mCH4 + sCO2 + dNH3

Given atomic weights: C = 12, H = 1, O = 16, N = 14. The mass of methane produced (in

grams, round off to 1 decimal place) per kg of raw MSW will be

Solution:

Let 1 kg of raw municipal solid waste (MSW)

Decomposable material = 70% of 1 kg = 0.7 kg

Water content = 35%