GATE Questions & Answers of Municipal Solid Wastes Civil Engineering

A city generates 40×106 kg of municipal solid waste (MSW) per year, out of which only 10% is recovered/recycled and the rest goes to landfill. The landfill has a single lift of 3 m height and is compacted to a density of 550 kg/m3. If 80% of the landfill is assumed to be MSW, the landfill area (in m2, up to one decimal place) required would be ______

The composition of a municipal solid waste sample is given below:


Component Percent by
Moisture Content
Energy Content
(kj/kg. on as-discarded basis)
Food Waste 20 70 2500
Paper 10 4 10000
Cardboard 10 4 8000
Plastics 10 1 14000
Garden Trimmings 40 60 3500
Wood 5 20 14000
Tin Cans 5 2 100

The diffrence between the energy content of the waste sample calculated on dry basis and as-discared basis (in kJ/kg) would be ______________

Solid waste generated from an industry contains only two components, X and Y as shown in the table below

Component Composition
( %weight)
X c1 ρ1
Y  c2 ρ2

Assuming (c1+c2) = 100, the composite density of the solid waste $ (\mathrm p) $ is given by:

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 uncompacted 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 _________.

A coastal city produces municipal solid waste (MSW) with high moisture content, high organic materials, low calorific value and low inorganic materials. The most effective and sustainable option for MSW management in that city is

Two biodegradable components of municipal solid waste are

Two electrostatic precipitators (ESPs) are in series. The fractional efficiencies of the upstream and downstream ESPs for size dp are 80% and 65%, respectively. What is the overall efficiency of the system for the same dp?