(SEM V) THEORY EXAMINATION 2022-23 SOILD WASTE MANAGEMENT

SECTION A (2 Marks Each)

(a) Composition of Municipal Solid Waste

Municipal solid waste consists of biodegradable waste such as food waste and yard waste, recyclable waste like paper, plastic, glass and metals, and inert materials such as dust, ash, and construction debris.

(b) Meaning of 3R

3R stands for Reduce, Reuse, and Recycle. It aims to minimize waste generation, reuse materials, and recycle waste to conserve resources.

(c) Role of Transfer Station

A transfer station is an intermediate facility where waste from small collection vehicles is transferred to larger vehicles for economical long-distance transportation.

(d) Refuse-Derived Fuel (RDF) System

RDF is produced by processing solid waste to remove non-combustible materials and convert combustible waste into fuel used for power generation.

(e) Gasification

Gasification is a process that converts solid waste into combustible gas by reacting it at high temperature with limited oxygen.

(f) Collection of Bio-Medical Waste

Bio-medical waste is collected using color-coded containers and bags as per Bio-Medical Waste Management Rules to ensure safe handling.

(g) Ultimate Disposal of Hazardous Waste

Hazardous waste is disposed of using secured landfills, incineration, or chemical treatment to prevent environmental pollution.

(h) In-Vessel Composting System

It is a controlled composting process carried out inside a closed container or reactor to speed up decomposition and control odor.

(i) Incineration

Incineration is a thermal process in which waste is burned at high temperature to reduce its volume and destroy pathogens.

(j) Activities of NGOs

NGOs create awareness, promote waste segregation, encourage recycling, support community participation, and assist municipalities.

SECTION B (10 Marks Each – Attempt Any Three)

(a) Factors for Selection of Collection and Transfer Alternatives

Selection depends on quantity and type of waste, distance to disposal site, collection frequency, road condition, cost, vehicle type, labor availability, and environmental considerations.

(b) Sources and Types of Solid Waste

Solid waste originates from residential, commercial, industrial, institutional, construction, and agricultural sources. Types include municipal waste, industrial waste, hazardous waste, biomedical waste, and electronic waste.

(c) Transfer Vehicles – Tractor and Container System

Transfer vehicles transport waste from collection points to disposal sites.
In the tractor and container system, containers are filled at collection points and transported by tractors, reducing handling and labor cost.

(d) Collection and Processing of Recyclable Materials

Recyclables are collected by municipal agencies, private contractors, informal waste pickers, and NGOs. Processing involves segregation, cleaning, shredding, baling, and sending materials to recycling plants.

(e) Pyrolysis Process

Pyrolysis is a thermal decomposition of waste in the absence of oxygen. It produces gas, liquid oil, and char, which can be used as fuel or raw material.

SECTION C (10 Marks Each)

Q3

(a) Design Principles of Solid Waste Management

Important principles include waste generation rate, population served, collection frequency, vehicle capacity, landfill area requirement, compaction density, calorific value, moisture content, and leachate generation rate, all expressed with proper units for planning and design.

(b) Functional Elements of Municipal Solid Waste Management

Functional elements include waste generation, storage, collection, transfer and transport, processing and recovery, and final disposal. Each element plays a vital role in effective waste management.

Q4

(a) Integrated Solid Waste Management (ISWM)

The three key steps are waste reduction, waste recycling and recovery, and safe disposal.
ISWM integrates technical, environmental, economic, and social aspects for sustainable waste management.

(b) Advantages and Disadvantages of Anaerobic Processing

Anaerobic processing produces biogas, reduces waste volume, and generates manure. However, it requires high initial cost, skilled operation, and longer retention time.

Q5

(a) Principle and Factors Affecting Composting

Composting works on biological decomposition of organic waste by microorganisms. Factors affecting composting include moisture content, temperature, oxygen supply, carbon-nitrogen ratio, and particle size.

(b) Leachate – Problems and Control

Leachate is polluted liquid formed when water percolates through waste. It causes groundwater contamination. Control methods include liners, drainage systems, leachate collection, and treatment plants.

Q6

(a) Salvage and Shredding in Integrated SWM

Salvage involves recovery of useful materials from waste, while shredding reduces waste size. Both help improve recycling efficiency and reduce landfill volume.

(b) Municipal Solid Waste Landfill – Description

A typical landfill consists of bottom liner, leachate collection system, waste layers, cover soil, gas collection system, and final cap. Key terms include liner, leachate, gas vents, and compaction.

Q7

(a) Role of Public in Solid Waste Management

Public participation is essential for waste segregation, reduction, recycling, cleanliness, and successful implementation of waste management programs.

(b) Infectious Waste from Hospitals

Infectious waste includes used syringes, blood-soaked materials, pathological waste, laboratory cultures, and contaminated dressings.