4- waste handling and separation, storage and processing at the source

Dr. Amirhossein Malakahmad

Civil Engineering Department

Universiti Teknologi PETRONAS

LO1: Prepare a plan for solid waste and

hazardous waste management

LO2: Analyze the legal requirements

Engineering PrinciplesWaste Handling and Separation,

Storage and Processing at the Source

Today’s objectives…

At the end of this session you will be able to:

Define fundamentals in waste handling and separation, storage and processing at the sources.

Evaluate storage of solid wastes at the sources and its effects.

Assess the processing of solid wastes at residential dwellings .

Agamuthu, EU-Asia SWM Conference, 2008

Agamuthu, EU-Asia SWM Conference, 2008

Agamuthu, EU-Asia SWM Conference, 2008

Agamuthu, EU-Asia SWM Conference, 2008

Agamuthu, EU-Asia SWM Conference, 2008

Agamuthu, EU-Asia SWM Conference, 2008

Handling and separation of solid

waste at the source

Handling: activities associated with

managing solid wastes until they are

placed in the container before collection.

Separation: separation of solid waste

including wastepaper, cardboard,

aluminum cans, glass and plastic

containers at the source of generation.

Waste handling and separation,

storage and processing at the

source

Characteristics of waste

Following functional elements

Public health

Public attitudes

Waste handling and separation at

residential area

Low-rise under four stories

Medium-rise from four to seven stories

High-rise over seven stories

Handling at low and medium-rise

apartment

Basement storage/curbside

collection

Basement storage room is provided for the

storage of solid waste. Typically a container can

be used for recycling.

Outdoor storage/mechanized collection:

Large waste storage containers are located outdoors.

The large containers are emptied mechanically.

Handling at high-rise apartment

1. Wastes are picked up by building maintenance personnel from various floors and taken to the basement.

2. Waste taken to the basement by tenants.

3. Wastes are placed by tenants in specially designed vertical chutes with openings located on each floor. Then wastes are collected in large containers.

Vertical chutes

Types and sizes of containers for solid waste collection

Storage of Solid Wastes

at the Source

Effects of storage on waste components

Biological decomposition

Absorption of fluids

Contamination of waste components

Biological decomposition

Food and other wastes placed in onsite

storage containers will almost immediately

start to undergo microbiological

decomposition (putrefaction) as a result of

the growth of bacteria and fungi.

Absorption of fluids

The components that comprise solid wastes have differing initial moisture content, re-equilibration takes place as wastes are stored onsite in containers.

If watertight containers lids are not used, waste can also absorb water from rainfall that enter partially covered containers.

Saturation of waste to their field capacity is a common occurrence in tropical region where it rains on most days.

Contamination of waste components

The major waste components may be

contaminated by small amount of wastes

such as motor oils, household cleaner and

paints.

The effect of this contamination is to

reduce the value of the individual

components for recycling.

Processing of Solid Wastes at

Residential Dwellings

Grinding of food wastes

Compaction

Composting

Combustion

Objectives in processing of solid

wastes

1. Reduce the volume

2. Recover usable materials

3. Change the physical form of solid

wastes

Food grinder

Grinding of food wastes

Grinders cause the food preparation, cooking and serving waste that passes through them suitable for transport through the sewer system.

Application of home grinder has resulted in overloading many treatment facilities.

In terms of collection operation, the use of home grinder does not have impact on the volume of solid waste collected.

But it will make possible to increase the time period between collection pick ups.

Waste compactor

Compaction

Although the compactors can reduce the original

volume waste up to 70% they can be used for

only a small portion of generated solid waste and

the weight of course remain same.

It is impossible to recover individual components

from compacted waste.

Where incineration is used, the compacted

wastes must be broken up to avoid delayed

combustion in the furnace and high losses of

unburned combustible materials.

Backyard composting

Composting

During the composting period the material placed in the pile will undergo bacterial and fungal decomposition until only a humus martial called compost remain.

Composting is an effective way of reducing the volume and altering the physical composition of solid wastes while at the same time producing a useful by-products and can be used as a soil amendment or mulching material.

In terms of home composting on the volume of solid wastes to be handled is relatively small.

Open burning

Combustion

Backyard incineration

Open burning

High-rise apartments incinerator Flue-fed incinerator

Chute-fed incinerator

Discuss the advantegaes and

disadvantages of each method

among your group members and

present in the class.