UNIT 1: WASTE COLLECTION SYSTEMS,

EQUIPMENTS AND VEHICLES

Structure
1.1 Introduction
Objectives
1.2 Components of a waste collection system
1.2.1 Collection schedule/ frequency of collection
1.2.1.1 Frequency of Collection
1.2.1.2 Time of Waste Collection
1.2.1.3 Shift Working
1.2.1.4 Days of the Week
1.3 Points of collection
1.3.1 On the street Collection
1.3.2 Inside the property Collection
1.3.3 Special Collection
1.4 Waste collection and storage systems
1.4.1 Loading
1.4.2 Segregation of the collected waste
1.5 Waste collection containers
1.6 Waste collection equipments
1.7 Waste collection vehicles
1.7.1 Small Waste Collection Vehicles
1.7.2 Agricultural tractors and trailers
1.7.3 Non-compacting collection vehicle bodies
1.7.4 Semi-compaction vehicles
1.7.5 Compaction vehicles
1.8 Summary
1.9 Keywords
1.10 Answers to SAQs

1.1 INTRODUCTION
While designing a waste collection system, it is important to properly understand
each stage in the collection system. They must be compatible with each other. For eg,
the container size would be important when the collection system requires holding of
waste for a long time. Similarly, the make of the vehicle would be a relevant
consideration if the collection system requires a waste carrying vehicle while driving
into a landfill. While designing any collection system, first we establish the overall
strategy and then adopt the specific components of the strategy like collection,
transportation and disposal keeping into consideration the interdependence of each
stages of waste management.
Objectives
After studying this Unit, you should be able to:
 understand various components of a waste collection system
 understand different stages in a waste collection system
 know about various equipments and vehicles used in waste collection system

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1.2 COMPONENTS OF A WASTE COLLECTION SYSTEM
Various components of a waste collection system includes
a) Collection schedule/frequency b) Collection points c) Storage containers d)
Collection workforce e) Collection route and f) Transfer stations
In this unit, we will be discussing about the collection schedule/ frequency, the
collection points, the storage containers and collection vehicles used.
1.2.1 Collection Schedule/ Frequency of Collection
A proper scheduling of waste collection is essential for effective collection of waste.
While planning a waste collection system various aspects that need to be taken into
account are frequency of waste collection, time of collection, shifts of working, and
also the days of the week on which waste is to be collected.
1.2.1.1 Frequency of Collection
The most crucial factor in waste collection system is the frequency at which the
waste is collected. Daily collection of small quantity of waste may be financially
viable in areas where labor cost is low and the collected waste can be carried in small
vehicles. However, waste collection on a daily basis in other settings can be a costly
affair. One of the important factors for a good system of waste collection is to inform
the waste generators beforehand when the waste will be collected and also when are
the holidays on which wastes will not be collected. This removes ambiguity and also
prevents the possibility of dumping waste on the streets. The other crucial factor is
that waste collection should be designed in such a way that periodic removal of waste
is commensurate to the waste that is generated. Otherwise it can give rise to dumping
of waste on the streets.
1.2.1.2 Time of Waste Collection
The time at which waste is collected is also an important factor. Usually the waste is
collected during the day time. Waste collection vehicles could block traffic in
crowded congested cities. In such cases, waste collection could be carried out in the
night time. The advantage of collecting waste at night is that in commercial areas and
markets, the daily cleaning can be done at the closing of the day and the waste can be
collected. In countries with extremely hot temperatures, working at night could give
a respite to the workers from the scorching heat of the day.
However, there are certain disadvantages to collecting waste at night. The noise of
the collection vehicles could be a cause for complaint by residents. Also, the poor
lighting can affect the process of waste sorting.
1.2.1.3 Shift Working
It is a general practice to collect waste in shifts. Usually this process is completed, in
the residential areas, in the first half of a day e.g. from 7:00am to 2:00pm. The
attempt is to complete the entire work in this shift and to complete any remaining or
unattended work after this shift. A work shift like this also helps in devoting time for
resting and maintenance of vehicles.
1.2.1.4 Days of the Week

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The collection of waste could be done daily, bi weekly or on alternate days. A daily
collection system would have a 6 days/7 days per week routine. If the collection is
for all the 7 days of the week, taking into consideration a day off, a larger work force
would be needed- so that a weekly off in staggered form may be provided to working
staff. Secondly, even if a daily collection system is in place, the containers provided
need to be capable of holding waste of at least two days’, accounting for holidays
when the waste may not be collected.
Collection on alternate days could imply a larger waste accumulation over the
weekend.

1.3 POINTS OF COLLECTION

The point of collection is the interface where the waste transfers from the generator
of waste to the agency which collects waste. Community collection is a cost effective
way of waste collection as compared to collection from each household. Some of the
concerns in this type of collection system are:
a) Sometimes, the waste may be scattered on the streets by animals or wind
before it is collected
b) There is a possibility of foul order emanating from the waste and causing
pollution in the residential area, when the collection point is very close to the
residential area
c) Waste spill over on the streets can cause problems for pedestrians or for
traffic. Also, it could be unsightly to perceive.
d) Rodent and pest infestation is a possibility near the waste collection point
For community collection, usually there are three main locations considered for
transfer of waste from generator to collector
 On the street, near to the point of generator
 Near the property boundary, on the street
 Inside the property
These are discussed in detail below:
1.3.1 On the street Collection
On the street collection may be carried out by using community/ street containers or
through block collection system
i) Community containers or street containers
In this method, collection containers are placed on the streets and the residents bring
the waste to these collection containers and leave the waste in them. Later, the waste
collection vehicles of municipality come to collect the waste from the containers.
For the success of this system, the distance that a person has to walk to dispose the
waste from their household to the collection container becomes an important factor.
This determines the number of collection containers to be provided and at what
distances. This is because as the walking distance increases, there is a likely chance
that the waste is not disposed off at the container but somewhere on the street.
Studies show that locating the containers at an interval of 160m to 200m is effective
for this system to work.
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The advantage of this system is that wastes from multiple points reach a single point,
making the collection by the collection agency easier.
The disadvantage of this system is that spill over of waste can occur on the streets
giving an unpleasant appearance on the street. It is also possible that nearby residents
and shopkeepers object to having containers in their vicinity. Crows, dogs, cats and
other animals could rummage through the waste and cause inconvenience. There is
an alarming possible situation wherein, someone might set fire to these waste if they
are unattended for a long time and start emanating foul smell. This could invariably
burn and destroy the containers and also cause poisonous gases like dioxins and
furans to be generated. Plastic burning is a serious long term health hazard; stringent
laws should be in place to prevent this. This can be avoided if waste if cleared
frequently, preferably two days and maximum three days. Otherwise, the waste starts
decomposing causing complaints by residents. This is all the more important in hot
humid climates where the decomposition rates are high. In colder climates, a longer
gap between collections may be permissible.
ii) Block collection system

Block collection is a system involving a vehicle and crew and is of low-medium

labor and vehicle productivity. In this method, a small open truck goes through a
determined route, announcing its arrival through a bell or music. People bring waste
from their houses and empty them in to the collection vehicle or hand it over to the
crew who empties the waste into the vehicle. In this method of waste collection, the
timing of the vehicle going into the residential areas is important so as to ensure that
the residents are available in their houses to bring the waste. If there are largely office
goers in a particular place, it is important to plan the collection time accordingly to
ensure that the collection is at a time, say before or after usual office hours.
iii) At the property boundary-kerbside collection
This is a method that is increasingly practiced in high income areas of developed
countries. Here, the waste is brought by the residents to the pavement near their
property line. For this to be successful, the residents need to be informed about the
collection timings in order to avoid the waste being left out and eventually leading to
scatter. It is important to keep the collection timings regular in order to avoid
scattering of waste. This also avoids theft of waste containers which can happen if
left out for a long time. In some cases, the segregation of waste is required of the
residents.
1.3.2 Inside the property
Below, we will discuss the cases when the waste is collected from inside the property
of the resident
i) Back door collection
In back door collection, waste collection is the responsibility of the agency. In
such cases, the participation of residents is low. The waste collection agency
comes with their vehicle, enters the property of the resident, and collects the
waste that is kept ready for collection. This is a more expensive and labor
intensive method of waste collection. Since the resident involvement is low, time
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 delays in opening and closing the gate is a drawback in this method. It is viable
when the collection is less frequent, say, once a week or so. This method is
practiced mostly in developed countries. Also weather plays an important role as
this method will not work well in hot humid weather as the waste hold time is
longer between collection trips.
ii) Collection from apartment buildings
In multi-storied apartment buildings, a common practice is that the residents can
leave the waste at a collection point on the ground floor. The collection agency
then collects it from here.
There is another practice where sanitation workers go from door to door in the
apartment collecting the waste kept outside or knock and ask residents to keep the
waste outside. Though this is a labor intensive process, this has been found
successful in residential areas of cities like Delhi.
1.3.3 Special collections
Special collection systems are adopted for collection of foliage or garden waste and
animal carcass waste. Usually, the foliage or garden wastes are collected on request
by the residents as the waste generation in this case is irregular. These services may
be also availed from the department in local bodies responsible for maintenance of
public gardens and trees on the streets. Since this waste is bulky in nature the choice
of collection equipment and vehicle is very important. Large open trucks with a
hydraulic crane fitted with suitable grab attachment are recommended for this such
collections. If a shredder mechanism is also provided, it helps in reducing the volume
of the waste and the collection trips can be reduced. This can also be done manually
by laborers who can cut down the tree branches and load them on to the truck.
In cases, when there is a predictability of the bulk waste thus generated, the
collection agency can notify the residents in advance and the waste can be dropped
off at special collection containers. In such cases, the waste needs to be removed
within one or two days to avoid decomposition and contamination. This becomes
very important if the waste is damp, which often is the case with garden wastes.
Whenever waste is generated from animal slaughter, the waste has to be collected
within 24 hours. In case of carcass of dead animal is found on streets, it has to be
immediately removed.
SAQ 1
a) What are various components of a waste collection system?
b) What are various considerations to be made in the design of a waste collection
system?
c) Write a note on the location of waste collection points.

1.4 WASTE COLLECTION AND STORAGE SYSTEMS

1.4.1 Loading
The process of transferring waste from storage to collection vehicle is an important
aspect of waste collection system. We need to ensure adequate compatibility between
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the storage containers and the transportation vehicles. The dimensions of the
container and the mechanism of transferring the waste becomes crucial in designing a
waste collection system.
When this transfer is made manually, the labour cost is low. However, it also implies
that the waiting time for the vehicle is large and results in lesser trips that the vehicle
can make. In manual transfer, there is also risk of the workers being exposed to
unhygienic conditions, dust and fungal spores, skin contact with waste, injuries while
of lifting and accidents.
1.4.2 Segregation of the collected waste
While designing a waste collection system, one important consideration would be
whether to segregate the waste at the source or not. This ensures that the materials
which can be recycled are separated from materials which cannot be. Sometimes,
segregation just happens at the source and they get mixed in the vehicle due to lack
of segregation facility. This defeats the purpose of segregation. Some vehicles are
designed with separate compartments for different wastes.
Waste collection from different areas also help in better utilization and collection of
waste. For eg, in case the waste is further used in animal feed etc, it would be
advisable to collect waste from markets, restaurants and eateries instead of with the
rest of the municipal waste. It is a good practice to separate the waste collected from
sweeping of streets from the domestic waste. Similarly, biomedical wastes from
hospitals and industrial wastes are collected separately and not with municipal wastes.
Further, such wastes of deposited in landfills are done in areas which are cordoned
off without any access to ragpickers, considering the risk it could pose to them.
Another good practice while collecting waste is to separate the wastes based on the
intensity of its content. When there is a large density of waste eg: sand and debris
from construction sites are carried in separate vehicles and not mixed with the rest of
the municipal waste.
Collection system design depends on distance between collection areas and disposal
site. Sometimes a single vehicle maybe employed to collect the waste from the
source to the destination. This type of collection system is called direct collection
system ( Ref: Fig 1.1). This would work well in case the distances between the
source and destination is low. In case, the vehicle for collection is too small and/or it
has to travel a large distance to dispose of the waste, it would be more advisable to
transfer the waste at an intermediate point to another vehicle. This system is called as
two stage collection system (Ref: Fig 1.2). In this waste from several small
collection vehicles are transferred to a single larger/faster vehicle for onwards
transport to the destination.

Figure 1.1 Direct Collection

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 Figure 1.2 Two stage collection

Two stage system is popular in high density residential areas and in large cities
where the disposal area is in the outskirts. In residential areas with narrow congested
streets, collection is made by smaller vehicles (primary vehicles), transferred from
collection point to larger vehicle (secondary vehicles) and then taken to the disposal
site. Small vehicles driving all the way from collection point to disposal site may not
be feasible or ideal. Larger vehicle would be f aster. Also the trips can be scheduled
in such a way the larger vehicle operates at night ,thus helping in reducing traffic
congestion.
In cities like Delhi collection of waste is made manually at the local areas, brought to
a collection point and then it is transferred to and transported by municipality
vehicles.
Similarly, adding one more layer of transfer makes for a three stage collection
system (Ref: fig 1.3). Adding more stages in the system makes it more complex and
it requires more management and effort while it could make the system less reliable.
SAQ 2
Distinguish between direct collection and two stage collection system.

1.5 WASTE COLLECTION CONTAINERS

The four basic elements of any solid waste management system is storage, loading,
transport and disposal. Each of this elements need to be compatible with each other
to be able to have an economical system. While choosing the containers for storing
waste, it is important to ensure that the waste does not come in contact with the
ground at any point in the waste management process. If containers become defunct
easily and have to be replaced, it can adversely affect the cost of the waste
management system.

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Requirements of a good container
One of the primary requirements for a container is that it should be ergonomical and
with ease of use for even young children. For this the placement height of the storage

Figure 1.3 Three stage collection

container is to be given importance. A convenient storage container will ensure that
the waste is placed inside instead of being littered around the container. The size of
the container is determined by the quantity of waste generated and the holding time
of the waste. A container tapered at the bottom helps tipping easier. Ideally, there
should be a cover for the storage container to prevent wind from taking away the
contents and also for preventing rainwater seepage. It is important that the waste is
kept away from the soil at all times so that there is no infestation of flies and rodents.
Sharp crevices and corners are avoided for the containers as these can be areas for
potential corrosion.
Materials used for containers
The material used for containers should be durable, able to withstand hot ashes, fire,
ultraviolet rays and corrosion. Wheels of the containers are to be made of sturdy
materials as they are points of wear and tear. If the bulk of the waste is organic, it
could cause corrosion of the containers- especially when the material is mild steel. In
order to avoid this, corrosion resistant steel is used for containers. These are more
expensive than mild steel. If mild steel containers are vandalized by arson, they have
to be repainted to replace the galvanizing and the protective coating. Else, corrosion
can set in.
Types of storage
a) Primary storage
At the primary storage level which has primarily domestic waste, household bins and
plastic bags are used. Plastic or galvanized bins are a slightly expensive option as a
primary storage.

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A low cost storage solution would be recycling the used tyres of cars and trucks (of
30 to 80 litre capacity) as storage containers. These prevent flies, can be washed and
are sturdy.
Another low cost solution is reusing old oil drums. This is not a very desirable
options as it is a slow and lengthy process.
b) Community waste storage
The secondary storage is at the level of community- where the waste generated by
several households are brought to a common point. Bunkers are a common storage
mechanism at this level. While selecting a storage container, design considerations
would be the volume of waste generated ( which is dependent on the local
population), daily per capita waste generation and number of days when the waste
would be stored in the container before it is cleared.
From the primary collection centers, the waste is brought to the community waste
storage unit. These are bigger containers. In addition to residential waste, other
wastes like construction waste, waste from nearyby shops, waste from street
sweeping and garden waste are also disposed in community waste storage.
Based on how they can be moved, community waste storage are classified as:
i. Stationary or fixed facility
ii. Portable bins
iii. Exchanged containers
They are described in detail below:
i. Stationary or fixed facility
In this type of community storage, the waste container is not moveable.
They could be :
-Uncovered enclosures or designated areas
- Covered galvanized or masonry bins up to 2m³ with loading option through top and
unloading through bottom
-concrete pipes or steel pipe sections upto a volume of 300 litres
These are not considered the best practices when it comes to waste disposal. The main reason
is that these cause scattering of waste and creates unhygienic premises. Rodents, flies and
insects, animals can be attracted to waste. Additionally, the exposure to weather conditions
like rain can be a problem.
There are also operational difficulties with regard to this waste collection system. Since the
waste is dumped, its collection would require raking which is usually done manually. This is
not a hygienic practice.

Such community storage facility need to be provided with covered facility so as to keep off
rainwater.
ii. Portable bins
Portable bins have been used for garbage collection ubiquitously. There are different kinds of
material and sizes for these containers.Plastic and galavanized sheet are the common
materials used for construction of these containers. The capacity may vary between 1 to 3
cubic meters.
These containers are emptied into secondary collection vehicle by a lifting mechanism and
then put back in the same position. They usually have four wheels to help roll over uneven
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surface and also align with the lifting equipment of the vehicle. Some compaction vehicle
have lifting equipment as part of the vehicles.
A frequent problem of these containers is the damage of wheels and combined with high
density of waste, this can cause difficulty while being towed. Damage of wheels make these
containers less efficient. Therefore, the preferred material is anti corrosive steel sheet with
high thickness for waste which is of high density.
iii. Exchanged containers
In the previous section, we saw portable containers were used to empty waste into
transportation vehicles and then carried to distant location for emptying. In
exchanged containers, the container along with the waste is carried by the
transportation vehicle to destination which could be a sorting point, landfill or
treatment plant. The transportation vehicle leaves an empty counter before
exchanging with a container containing waste.
One advantage of this system is that the delay in collection of waste is small. The
time taken to place the container on the transportation vehicle and exchange it with
another one is low. If there is adequate tipping gear installed on the vehicle, it is easy
to off load the waste also. The labor involved can also be minimized if the system is
well mechanized. Another advantage is that multiple trips can be carried out by the
same vehicle, increasing the productivity of the system. Container system vehicles
are capable of making up to five times the trips.
Exchange containers can be used at the source ie community collection or can be
used at the second stage in transfer system where waste from many sources are
transferred to a common vehicle. They could also used in areas were thequantity of
waste is high, ie markets. They can also be used in industrial and institutional waste
where the waste is non biodegradable in nature.
While using exchange containers for biodegradable waste like residential wastes, it is
important to empty the containers frequently, at least once in 2 days to avoid
problems due to degradation of waste- bad odor, rodents, insects flies etc.

Fig 1.4 Fig 1.5 Fig 1.6

6m³ tractor trailer 4m³ skipper (lugger) 10 m³ hooklift container
container container
Above are the examples of exchange containers. They act as collection source and
when it is time to clear, they are loaded on to a transportation vehicle and disposed off
to the disposal area/for recycle

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SAQ 3
Write short notes on the different kinds of community waste storage systems.

1.6 WASTE COLLECTION EQUIPMENTS

In a waste collection system various kinds of tools, equipments, carts etc are used
depending upon the type of waste collection system. A number of hand tools are also
used in addition to various sweeping machines used by the workers employed in
waste collection. These are discussed below.

a) Sweeping machines
i. A large quantity of city pollution (38%) is contributed by road dust. In
order to avoid suspended particulate matter (SPM) pollution caused by
manual sweeping and also for increased efficiency, mechanized road
sweeping machines ( MRS) can be used for road sweeping.
ii. These machines are moved by slow moving vehicles which move at 8km
per hour. They use vacuum suction to remove dust and also sprinkle
water remove dust suspension.

Fig 1.7: Mechanised Road Sweeping machine in Delhi

Pic courtesy: author

For smaller areas, there are handheld sweeping machines also operated by a single
individual.
b) Hand Tools
There are various hand tools which are used for collecting waste. It is important that
these tools are ergonomically designed. Brooms are the most common of the

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handheld tools used. There are two main kinds of brooms used for cleaning
horizontal surfaces- stock broom and the bunch broom

Fig 1.8: Bunch broom Fig 1.9: Stock broom

While using bunch brooms, the shoulder In stock broom, only the arms muscles are
muscles are employed and larger area is exercised and area covered in one sweep is
covered smaller as compared to bunch broom

The other hand tools that are used for cleaning of streets and drains are forks, drain
drags and shovels. Forks are used to pick the waste, their edges are raised slightly to
prevent waste from falling off. They also have rounded tips so as to not pierce
polythene bags, aluminium cans etc. Drain drags are used for cleaning and they have
sharp edges to remove obstacles. Additionally, each worker is provided with a scoop
to collect the waste together and deposit them in their carts. A common an
inexpensive practice is to use two boards together. Scallops made of metals are also
used in some places.
a) Square shovel
b) Drain drag
c) Refuse fork
d) Digging shovel

Fig 1.10: Other hand held tools used for collecting waste

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c) Hand carts
Hand carts and wheel barrows are used to transport waste from one place to another.
The diameter and the material of the wheels of the hand cart depends upon the load
carried, the surface of the road. Pneumatic tyres are preferred for wheels as they
perform better under heavy loads. However, frequent punctures could be a problem.
The carts should be designed in such a way that the self weight is low but durability
is high. They should also be able to maneuver easily especially through narrow lanes.
The design of the handcart should take into consideration they can be moved around
without the operator having to stoop, and with ease to lift the weight and also for
changing bins.

Fig 1.11: Hand cart Fig 1.12: Drain cleaning

equipments, Delhi
Pic courtesy: author

d) Litter Bins
Small litter bins which are smaller than the community bins can be provided at
regular intervals in a street for passersby to drop waste material. An anti litter law in
place would be the way that litter bins will be effectively used. Litter bins should be
neat and clean with ease of use. Usually litter bins have a pivot based tipping
mechanism to empty their contents. Some of them have covers to keep out rain and
also drain holes to allow drainage of water. One risk of litter bins is that people may
throw burnt cigarettes into the litter bins and cause a fire to catch. In such a situation,
plastic containers are not advisable.

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 Fig 1.13: Litter bin Fig. 1.14: Emptying of a
litter bin

SAQ 4
What are –?
 Hand tools
 Hand carts
 Litter bins

1.7 WASTE COLLECTION VEHICLES

The usual practice of waste collection is that the collector moves in area with
collection vehicles, collecting the waste. These vehicles may be manually operated
using muscle power, or animal drawn or machine powered. The choice of the
vehicles depend upon the quantity of waste to be generated, the surface of the road on
which it moves, the distances between waste collection points etc. Accordingly, the
following are some of the waste collection vehicles commonly used.
1.7.1 Small Waste Collection Vehicles
i. Handcarts and tricycles
Usually in areas with high density of residences and where navigation of bigger
vehicles is difficult, handcarts and tricycles are employed. These are usually human
operated and are used in short distances. Hand carts are employed in 1km radius and
tricycles can be employed up to 2km radius. Since these vehicles are human powered,
they work in areas where there is no slope.
Tricycles are operated by pedaling. The waste is collected in a container atop the rear
wheels. For ease of carrying loaded tricyles, the design of the tricycle, its load
carrying compartment and the wheels itself if very important. The tricycles chosen

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should be in such a way that their load carrying capacity is larger than the waste
collected so that spilling of waste does not take place.
These vehicles may carry containers with waste and may or may not have mechanical
lifting equipments to tip these bins. The other option for transferring of the waste is
by tipping the vehicle and transferring the waste to a container at a level lower than
the tricyle.
If recycling also takes place simultaneously, while collecting the waste,it is important
to provide additional hooks for handing the plastic bags for storing recycled or
segregated objects.
Since these vehicles are not motor powered, a driving license is not mandatory for
the persons who operate it and it makes this method advantageous.
ii. Animal transport
Animal transport of solid waste is practiced in certain countries like Egypt and
Pakistan. This mechanism is effective in areas up to 5km in radius. Animals like
donkeys, horses, mules and buffaloes are used for this purpose. This method of waste
collection using animals for transport of waste is not often practiced nowadays.
iii. Motorcycle trailers
We have been discussing human and animal powered vehicles for transporting waste.
Now we will look at machine powered vehicles for transporting waste. As we saw in
the previous cases, the compactness of the vehicle is an important factor during
collection of waste in congested areas. A two wheeled motor cycle drawing a trailer
is the simplest form of mechanized vehicle. The advantage is that it is fast moving
even though its load carrying capacity may be low.

iv. Two wheeled tractors ( power tillers)

Two wheeled tractors are of a higher capacity than motor cycle trailers and they can
navigate bigger distances up to 8km. They are also two wheeled vehicles which run
on diesel engines of capacity 6KW to 12 KW.
They are very effective in employment at the level of waste collection at primary
levels and for subsequent transfer at transfer stations. They are best suited for
collection in a distance of 8km and travel at a speed of 20km per hour. They lack
suspension and that limits their capacity to carry waste- carrying up to eight to ten
bins of hundred to one twenty litre capacity. However, since the engine speed is low,
these vehicles last long and consumes less fuel. Two people are needed to operate
collection mechanism using two wheeled tractors- for loading and unloading of waste
and for transferring it at transfer points.

v. Three wheeler auto rickshaw

Autorickshaws are ubiquitous mode of transport in India and some of the south Asian
countries.It is a mechanized form of the cycle rickshaws with a cabin for the driver
and a rear space for cargo. It rests on three wheels and is resistant to toppling. The
rear cabin for cargo is of 1 m³ capacity.
It has got a narrow frontage and can travel at high speeds of up to 30 km per hour.
For this reason, they are best used in congested parts of cities. The preferable
distance between waste collection and transfer stations in the case of these vehicles is
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5km. The waste is transferred by either by lifting the front of the autorickshaws
manually or by raising the rear portion holding the waste bins using handpumped
hydraulic tipping cylinders. These days, these vehicles are made with single cylinder
diesel enginers with four strokes and are environmentally less polluting as compared
to other vehicles.

Fig. 1.15: Rickshaws with hydraulic tipping mechanism

Picture courtesy: Chintamani motors

vi. Micro-truck with refuse body

Another small waste collection vehicle is a micro truck fitted with a collection
chamber to collect waste. These chambers usually have capacities of 1.5 m³ and
maybe covered or uncovered. These chambers have in built mechanism and so the
waste collected in them can be directly tipped to transfer stations by lifting and
tipping the chamber. Due to the ease of transfer of waste, using micro trucks for
waste collection is highly effective. The small size and the speed helps it navigate
high density areas and as the chassis of the vehicle is of low height, the lifting and
placement of waste on to the micro truck is easier.
SAQ 5
Discuss the various small waste collection vehicles used in the context of developing
countries.
1.7.2 Agricultural tractors and trailers

Tractors attached with trailers

Tractors are commonly used for agricultural activities in developing countries. When
attached with a trailer they can be employed for solid waste collection and transport
and can be more advantageous to use as they are durable and less expensive as
compared to trucks. They have a low engine speed and contributes to longer duration.
Their speed is low- approximately 30km per hour and can be used in a radius of up to
20 km and in some cases upto 40km. In order to improve to have a smaller turning
radius while navigating, a ‘swan neck’ design trailer drawbar is considered more

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effective. The transfer of solid waste from these tractors are made by the tipping
action of the trailer using hydraulic mechanisms.
1.7.3 Non-compacting collection vehicle bodies
In developing countries, the waste is of high density that the compaction of waste is
not needed most of the time. Compactor vehicles, as the name suggest compact and
reduce the volume of the solid waste collected enabling larger quantities to be
collected per load. They are more expensive as compared to the non compacting
collection vehicles due to additional mechanism needed to compress them
hydraulically. Non compacting collection vehicles use a tipping mechanism to empty
the waste. The centre of gravity, angle of tipping and the location of the hinge
position of the tipping truck play an important role in the effectiveness. Usually,
tipping angles of 55º is used for the waste enclosure while emptying waste otherwise
waste will not be completely emptied. Some of the examples of non-compacting
collection vehicle bodies are discussed below:
i. High-sided open-top vehicles
These are commonly used in developing countries and involves usually
tipping trucks with higher sides. The waste is loaded on to them manually
using showels and at the transfer stations, they are tipped to empty the
contents. These are commonly used because tipping trucks are commonly
found here and in some cases easy to assemble too. However, due to the
nature of involvement of manual labour- which involves raising the waste
above over the heads of the labourer is unhygienic and hence not a
recommended practice of solid waste collection. Further, during the
transportation of the waste in such vehicles, there is a chance of the waste
flying away from the top unless properly secured with a tarpaulin etc
which is seldom practiced. However, the fact remains that this is the least
expensive of non compaction vehicles.

ii. Side loading “roll-top” vehicles

This is also a type of non compaction vehicle used in developing
countries. These are vehicles fitted on a truck chassis with a semi
cylindrical top where the waste is loaded from the sides through curved
sliding doors. The mechanism of emptying is by tipping. The
effectiveness of these vehicles is determined by the kind of waste that is
carried. However, if it is used to carry waste in waste containers of
standard size, then they can have a better efficiency in payloads ( payload:
amount of waste that is carried). These vehicles are common in
developing countries and often can be manufactured locally.

iii. Front-loading high-sided enclosed vehicles

These vehicles are commonly used in African countries and are
considered better than the high sided open vehicles that we discussed at
the beginning of this section. It consists of a closed enclosure for carrying
the waste located behind the driver’s cabin. There is small space between
the enclosure and the driver’s cabin which can be accessed by climbing
through steps. The process is handled by a single person. The waste is
transferred from the ground to the person standing on the platform and
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 transferred into the enclosure through an opening. When the enclosure is
filled, it is tipped keeping the rear doors closed. This helps push the waste
to the rear of the enclosure to provide more space in the front to
accommodate more waste. At the transfer station, the waste is emptied by
tipping the container and waste is let out through door(s) at the rear end.
These vehicles are called as “tipacks”

The advantage of these vehicles are that they are locally manufactured
and the waste can be covered during transporting. The disadvantages are
that it is managed by a single person and therefore loading time is slow.
Additionally, there is a limit to the size of the waste containers that can be
carried by a single person which again affects the loading time.
iv. Fore-and-aft tipping bodies
Fore-and –aft tipping body vehicles are rear loading vehicles with tipping
action in two sides. These were popular in Europe during the 1950s and
1960s. The waste is loaded through the rear and the tipping action tips it
towards the front to allow space for more waste to be accommodated at
the rear side. Sometimes, a metallic plate insert maybe provided in the
middle of the body of this enclosure attached from the roof. This is to
prevent the backflow of waste. A tipping action is used for emptying the
enclosure at the transfer station.
The waste gets compacted by self weight and thus reduces the volume of
the waste. A waste density of 250kg/m³ is recommended for these kind of
vehicles.
v. Side loading bin lift system
As the name suggests, this is a mechanism in which the bins from the
primary collection centers are lifted and emptied into the body of truck
through the roof hydraulically or by other mechanism. The compatibility
of the bins and the hauling mechanism becomes an important factor and
therefore, standardized containers are to be used. The lifting mechanism is
part of the vehicle. It hauls the bins and empties the contents in to the
body of the waste collection vehicle. When the front is full, the body is
tipped back with the rear door closed. This makes additional space in the
front for more waste to be added. This is a preferred mechanism as it
eliminates the manual hauling of containers which could eliminate
musculoskeletal disorder associated with manual operations of heavy
containers.

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 Fig. 1.16: Truck fitted with bin lifter
Copyright: open.edu

vi. Crane-tipper system

A crane tipper system employes a truck attached with a crane. The truck
parks to the side of the road and the arm of the crane extends out and lifts
the waste containers and empties the content into the waste into the body
of the truck from the top. The movement of the crane is controlled by the
operator of the truck. The crane arm can extend up to 8m to pick the
containers making it an easy mechanism where the containers are not
located close to the street. Further, the location of overhead cables have to
be considered as the these could be in the path of the swing of the crane.
The waste can be covered while traveling. The emptying of the waste is
by a tipping mechanism.
The advantage of this vehicle is that time needed for loading the waste is
low and the operation only needs one person. This method is popular in
Gaza area in Palestine.
1.7.4 Semi-compaction vehicles
In the previous section we have learned about the non-compaction collection vehicles.
Now we will look at the various types of semi compaction collection vehicles. These
help in reducing the volume of waste of medium to high density. No complex
machineries are used for compaction and therefore are a preferred type of vehicle in
developing countries.
i. Side-loading, moving-barrier, semi-compaction vehicles
In this type of vehicles, the waste is loaded through small openings on
either side of the body of the vehicle. These openings are located close
to the front of the vehicle. Once the waste is loaded through the side
openings, a packing plate pushes the waste to the rear of the vehicle.
At the transfer station, the waste is expelled through the rear side
where there is an opening to let out the waste.

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 The risk in this type of vehicles is that, because of the slow loading,
sometimes people may enter the waste chamber to manually push
back the waste in order to accommodate more waste. However this
can be dangerous and can cause crushing of the person by the packing
plate.

ii. Fore-and-aft semi-compaction vehicles

This mechanism is very similar to the fore and aft vehicles discussed
earlier in the chapter except that in this type there is a plate that is
suspended from the roof of the waste enclosure that crushes the waste
and moves it to the front of the vehicle.

This type is ideal when the waste is stored in containers or in

cardboard boxes. The compaction plate can compress them and let the
air out.

iii. Side-loading-hopper semi-compaction vehicle

This vehicle is used mostly in developed countries and is used for
medium density waste. In this mechanism a portion of the side of the
body of the vehicle opens up to receive waste. It is compacted and
pushed to the other side of the body. Once the waste is filled and the
content has to be expelled at a transfer station, it is done so by tipping
the body of the vehicle from the rear side.

The disadvantages of this vehicle that the size of the vehicle is such
that it can not pass through narrow streets. Further, loading of the
waste is a slow process.

1.7.5 Compaction vehicles

When collection vehicles have inbuilt mechanism to compact the waste, the volume
of the waste is reduced and more waste can be accommodated per trip. In developed
countries, the waste generated has a density between 100 kg/m³ to 150kg/m³ and after
compaction it becomes 400- 500kg/ m³. This is a significant reduction in volume and
increase in density.
In developing countries, on the other hand the waste generated is of higher density ie
250 to 400kg /m³. Significant reduction in volume as in the case of waste generated
in developed countries cannot be achieved here due to the nature of waste. Further,
the reduction in volume can cause increase in the weight of the load which can
overload the vehicle. Hence, in built compaction mechanism may not be effective in
waste collection practices of developing countries as in the case of developed
countries. Further, the sand and abrasive materials that is found in the waste collected
in developed countries can damage the compaction mechanisms. Therefore,
compaction vehicles are not really suitable for developing countries, even though
their use is predominantly found here.
The use of compaction vehicles is determined by the density of the waste. These
become effective when the maximum payload cannot be achieved by non-
compaction vehicles.
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 i. Rear-loading compaction plate compactors
The rear loading compaction plate compactor vehicles are common in developed
countries and the technology is now increasingly adopted in developing countries.
These vehicles work well with low density weight.
The main parts of these trucks are a large hopper where the waste is fed into, a
compaction plate which sweeps the garbage into the body of truck and an internal
ejector plate which gets pushed as the garbage is pushed in. The pressure of the
compaction plate and ejector plate crushes the waste. When the garbage is to be let
out, the compaction plate is made redundant by the use of hydraulic mechanism and
the ejector plate pushes out the waste.
In this system, the whole mechanism of compaction ( plates and hydraulic parts)
itself forms a bulk of the weight of the vehicle, approximately 3500kg. The
conversely impacts the amount of waste the truck can carry.
Another important aspect of these type of vehicles is that the emptying of the waste
from the body of the vehicle can topple the vehicle due to the shift in weight unless
proper mechanism is in place. This is because in order to have an easy loading ( a
low loading height) the hopper into which the waste is fed into has to be behind the
rear wheels of the vehicle. This means the heavier machineries like hopper and
compaction plate are located at the rear end of the vehicle causing the bulk of the
weight to be concentrated here. Since the waste is compacted, it would have more
weight for the same volume of the body of the truck and could result in overloading.
In order to avoid this, the body of the vehicle is designed to be small. Since the
weight is concentrated at the rear end, this could also cause the front wheels of the
truck to get lifted up due to the shift in weight while unloading or while ascending a
slope.
In order to balance out this weight distribution problem, sometimes additional
weights maybe added to the front of the truck or springs to the rear of the truck.
The high organic content in the waste can cause corrosion of the hydraulic
machineries and can cause quick wear and tear.
The maintenance cost of these vehicles are high due to the machinery that is
used.They work well in conjunction with other primary collection vehicles
collecting waste from micro trucks and other small collection vehicles.

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 Fig 1.17: Rear-loading compaction plate compactors

ii. Screw compactor

As the name suggests, in this time of mechanism, a rotating screw mechanism lets in
the waste into the body of truck. This shreds the waste before its entry into the truck.
There is no compaction mechanism involved.
It is a very cost effective mechanism in developing countries as the machineries are
not very expensive and the screw can be replaced. The screw mechanism is less
expensive and less bulkier than the hydraulic compaction system that we discussed
earlier. For the same reason, it is possible to have this mechanism attached with
normal waste collection trucks and sophisticated and heavy vehicles are not required.

Fig. 1.18 :Rear-loading screw compactor

iii. Rotating drum compactor

The rotating drum compactor consists of a rotating drum into which the waste is fed
from the rear. From here it is pushed forward by helical blades which moves as the
drum rotate. Instead of the compaction action, the waste undergoes a pulverizing
action because of the helical blades and because of the friction of the rolling wastes.
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During evacuation of the waste, the opening at the rear end is opened and the
direction of rotation of the drum is reversed to let out the waste. Wearing of the drum
is an issued due to the friction. The loading process is also slow in this method.
However this is considered more effective than compaction vehicles while handling
dense wastes. This does not have the uneven distribution issue as we saw earlier in
compaction vehicles.
iv. Paddle compactor
In a paddle compactor, a semi cylindrical hopper is fitted with a paddle which moves
to either sides of the hopper. This paddle distributes the waste to either sides and
therefore weight is equally distributed.. There are two possible way by which waste
can be let inside- either trhough the rear end or through the space between the
driver’s cabin and the body of the vehicle. The loading height depends on the height
of the chassis of the truck on which the paddle compactor is attached to.
v. Front-loading compactor
So far, we have discussed rear loading of waste into a vehicle,ie the waste loading
happens on the rear part of the vehicle, behind the driver’s cabin. In this, the loading
of waste is from the front and is operated by the driver. This is a highly mechanized
system of waste collection where waste containers are picked from the ground using
forks and are carried over the driver’s cabin and emptied into the body behind. The
compaction takes place within the body and the compacted waste is pushed to the
rear side of the enclosure.
This is a highly efficient system and also highly expensive and requires large space
for operation. It is predominantly used in developed countries and can be operated by
a single person.
SAQ 6
Compare and contrast semi-compaction vehicles and compaction vehicles
Exchanged container systems
The way of transferring waste from the stationary containers to the vehicle is an
important aspect of waste collection. The compatibility of the container and the
vehicle and the loading and unloading mechanism plays an important role of the
efficiency of the system. Below, we discuss a few container pickup vehicles.
i. Tractors and containers
Container Pickup
One of the mechanism in container pick up is when the entire container is picked up
by the lift arms situated at the rear of the tractor. This is especially useful in places
with narrow lanes. Since there is a risk of the weight of the container causing
unsteadiness of the vehicle, weight adjustment in the form of ballasts are provided at
the front of the tractor.
Trailed container pickup
In a trailed container pickup set up, the tractors have in built mechanism to pick,
transport the trailers and tip them using hydraulic arms. Tractor- trailer container
systems are well suited for short to medium distances of upto 15km.
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 ii. Skiplift (load lugger) vehicles
In this system two hydraulic arms of the crane and chains are used to lift the
containers. The containers are emptied by tipping them after resting the container on
the deck of the truck. The tipping action is made possible by the arms of the crane.
This method is employed when the waste is heavy- eg construction waste and is not
suitable for residential or urban waste. This method is a slow process.
This method is also called ‘load lugger’,”bucket lift” or “dumper placer”.
iii. Roll-on and hook lift (arm-roll) systems
This is another mechanism where the container is pulled on to the deck of a truck and
transported to the transport station. Initially, the container is pulled from the front
using cables or chains and lifted. These cables are attached manually. The truck has
an inbuilt ramp like mechanism to lift and place the container on the deck of the
truck. There are metal rollers at the rear of the containers to aid movement.
Nowadays, the ‘Roll on” system has been replaced with a “Hook lift system”. In a
hook lift system, the same procedure takes place except for the roll on there is a
hydraulic arm with a hook that lifts the container through a metal loop on the
container.
These can carry a large amount of waste depending on the size of the container and
the capacity of the truck and can travel long distances. This is used commonly in
developed countries and smaller scale ones are used in small communities.
iv. Small container shuttle
A small container shuttle lifts small waste containers and ferries them to short
distances. They are based on the a modified chassis of construction site dumper.
These vehicles are 3 speed gears, 9 hp, single cylinder diesel engine vehicles with
low speeds of 20 km per hour. They are suitable to operate in congested areas with
uneven terrain. They use hydraulic arms to lift container of about 2 m³ capacity. An
example is Micrabin used in Maldives.

1.8 SUMMARY
The components of a waste management system like the timing and frequency of
collection, the collection points, the equipments and vehicles used all contribute to
the efficiency and economy of the system. The selection of these components have to
be based on the viability in a particular circumstance. A method that is successful in
a developed country may not work exactly in a developing country, owing to the
differences in the density of the waste generated, the terrain on which the vehicles
have to ply, the width of the roads, the cost of operation and maintenance of the
vehicles etc. By going through this unit, the learner must have obtained the basic
concepts of how each component of the waste collection system affects the overall
efficiency and economy of the system.

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1.9 KEY WORDS
Payload Capacity: A vehicle’s payload capacity is the amount of weight the vehicle
can carry within its cabin or on the truck bed. Anything you put inside your vehicle,
whether it be cargo or passengers, counts towards the vehicle’s payload.
Hopper : The hopper is the part of a garbage truck or compactor where trash is
emptied before compaction into the container.
Ballast: Heavy material as counterweight to provide stability for a vehicle
counterweight to provide stability for a vehicle

1.10 ANSWERS TO SAQ

SAQ 1 Refer to section 1.2
SAQ 2 Refer to section 1.4
SAQ 3 Refer to section 1.5
SAQ 4 Refer to section 1.6
SAQ 5 Refer to section 1.7.1
SAQ 6 Refer to section 1.7.4 and 1.7.5

FURTHER READING
Collection of Municipal Solid Waste in Developing Countries”, UN Habitat
Copyright © United Nations Human Settlements Programme (UN-HABITAT), 2010

REFERENCES
All tables and figures fromCollection of Municipal Solid Waste in Developing
Countries”, UN Habitat unless specified
Copyright © United Nations Human Settlements Programme (UN-HABITAT), 2010

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