Pneumatic
underground waste collection.
Sahana Iva Raghavan (siraghavan.2013@business.smu.edu.sg),
Bachelor Of Business Management, Singapore Management University.
1.1 Executive Summary
Waste has had an increasing effect on mankind over
centuries. Right from contaminating our resources, to breeding diseases to
destroying our environment, it has done no good. Now with the rising
population, the total amount of waste produced is increasing at an exponential
rate.
This report considers the application of an
effective and sustainable alternative. Pneumatic waste systems are a developing
technology that can be used for efficient and clean waste management. Given
below are a detailed history of waste collection systems and the origin and
revolution of underground systems. This is then followed by the current
position of waste collection systems and whether there is scope for this system
in the future. This report is concluded by an evaluation of the system and its
applications.
1.2 Introduction
Last year alone,
i.e. as of 2012, the total waste collected was 7.27-million tonnes. (Solid waste management, 2013). Every
year we accumulate all types of waste- domestic and industrial, solid and
non-solid, hazardous and non-hazardous, etc. The largest form of waste however
definitely comes from domestic waste systems such as households, offices and
restaurants. Domestic waste is the single largest cause for a variety of
problems ranging from lack of disposable area to generation of harmful
diseases. Domestic waste has also led to reducing the aesthetic appeal of the
areas it affects, causing many air and water bone diseases like pneumonia,
cholera, etc. (Health Impacts of solid
waste, 2013)
Waste has many
threats to pose. Waste may include any type of garbage or rubbish, which may be
from leftover food, to scrap paper to old items, etc. However, what we humans
fail to understand is that there is a direct relationship between increasing
quantity of waste and increase in diseases and environmental damage. Waste
produced accumulates a lot of space. In order to dispose the waste in any
method possible, large areas are going to be needed to store the waste until it
can be disposed. Waste management techniques like landfill sites also take up
large amount of a space. With an ever-growing population, there already exists
a critical pressure on land resources. With increased amounts of garbage, there
may not be place to accommodate the expanding population.
Apart from that,
waste collection and disposal includes a lot of time and effort. Transportation
of waste includes resources like money, fuel and manpower. Also it must be noted
that waste collection is a huge and tedious process, starting from door- to-
door collection, collecting from the public places, segregating the waste and
finally transporting it to the main sites where it is to be disposed. In the
process of collection, segregation and disposal, it is very likely that a lot
of waste will be “loosely” disposed, meaning that lots of waste is left
untouched and untreated. This is the most dangerous consequence of waste, as
these act as breeding grounds for diseases such as dengue. Also waste, which is
disposed into the water to flow down and reach the landfill sites, is another
major problem as it contaminates the water. Contaminated water can cause
serious health risks such as cholera and spread of other infectious diseases.
Solid domestic waste can become smelly and then attract pests and rodents. Also
there is the biggest threat, which is the release of the greenhouse gas,
methane. Methane is a gas, which captures heat 21 more times than carbon
dioxide, and hence poses a huge threat to increased global warming. (Green by Nature, 2009)
From the above
discussion, we can conclude that garbage is an increasing worry for people, and
if not treated properly can cause irreversible and serious damage to health,
environment and resources. This clearly implies that there is a need for a
fast, effective and sustainable method for dealing with waste collection and
disposal. That’s where the pneumatic waste collection system comes in.
These are
underground systems, which help transport and dispose waste through a largely
connected underground pipe network system, which will be explored later in
detail in section 1.5.
1.3 Historical
Perspectives
In order to
fully understand the process of waste management, it is important we consider its
past implications and how it all began. Right from 6500 BC, archaeological
studies prove that Native Americans produced
5.3 pounds of waste everyday. However around this period, man was known majorly
to produce biodegradable waste, which had close to a negligible impact on the
environment. (Wikipedia, History of Waste
management, 2013)
It was known to
be that the Mayans had “dumps”, which occasionally exploded.
This was the first ever known form of what we would come to call
“incineration”.
The first ever known municipal dump
in the Western world was found in Athens,
Greece in 500 BC. Around the late 14th century the English Parliament banned waste disposal
in waterways. This is known to be the first step that was taken in a mass form
of waste management, run by the government. Yet, waste was still in control and
posed no threat to humanity. (Wikipedia,
History of Waste management, 2013)
Around the 18th
century, however, events took a turn for the worst. With the advent of
industrial revolution, we saw the mass production of new materials such as
Steel, Copper and Aluminum, which formed the largest composition of domestic
waste at the time. This new form of waste played a colossal impact on history.
As these wastes increased, it led to the spread of infectious diseases such as the
Bubonic Plague, cholera and typhoid fever, which altered the populations of
Europe.
Figure 1. Roman sewages found in 800 BC
Reproduced from
Wikipedia, 2013
Resulting from
this came the awareness among people about the danger of waste. In 1885, the United States of America built the first
waste incinerator. In the late 19th century, recycling plants were
constructed as well. However, it wasn’t until the late 90’s that different
countries implemented laws about waste management.
As
far as underground waste management goes, the earliest form of this system was
found in ancient Rome between 800 and
735 BC in the form of sewers. It was a used to drain out the city’s dirt and
regulate the water supply. The Romans built a complex system, which included
the water being drained through central channels into the main sewage and
finally into the rivers. This system is based on the same principles as our
current pneumatic waste collection systems. The Roman sanitation was considered
the best-known artifact for its innovation, complexity in design and
effectiveness.
The first
pneumatic waste collection system originated in Sweden, with the first installation in Sollefteå Hospital in 1961.
It was the first time that the vacuum system was used in order to transport
waste in the multi-story hospital. With the great success of the system, an
1100-unit system was built for a multi-story housing complex in Sundbyberg (Stockholm, Sweden), which
was active by 1967. (Automated Vacuum
Collection, Wikipedia, 2013)
1.4 Current Situation
Currently, there
are numerous ways in which we chose to dispose off our waste. Some of these
systems, which have been around for centuries now are beginning to fail as they
pose an irreversible threat to our environment. People are currently more aware
about the ill effects of waste and the need for a solid waste disposal system
in all countries, as to ensure the overall sanity and hygiene of the population.
Some of the most common methods of waste disposal include landfills,
incinerators and composting.
Landfills: This system includes the waste being
transported to large open areas where it is then buried in landfill “sites”.
Typically, all forms of waste can be buried in these sites, which are then left
many layers underneath the surface of the ground. It is one of the oldest and
most commonly known methods implemented till date.
However,
landfills pose many harmful effects on the environment. The largest problem is
that landfills occupy too much space. Also they contaminate the groundwater and
leave the land barren, henceforth making it worthless
Incinerators: As discussed earlier, the earliest known
form of incineration came from the Mayans. Waste is loaded into huge
containers, which burn at high temperatures. This clears the waste fast, but
adds to air pollution and also is dangerous to operate.
Composting: This includes re-using organic,
degradable waste to add nutrition to the soils and act as natural manure.
Though this method poses no environmental damage, its shortcoming is that it
can be used only for biodegradable waste and not anything else.
1.5 What is a pneumatic waste collection
system?
The pneumatic
waste collection system, also known as Automated Vacuum Waste Collection
(AVAC), is a high-speed, underground waste transporting system.
This is a system
based on a network of fixed collection stations through indoor/ or outdoor
collection points. With the help of connected pipes, the waste deposited at the
drop-offs can be transported to the collection units. Exhausters create air
pressure in the ducts, and hence the air stream transports the waste through
the main line to the collection center. (Luiten
P., 1976)
Drop off
points
These are the
substitutes to dustbins. They are the starting point to the AVAC, and are very
vital, as it must be ensured that these drop off points are of the right size
and are well sealed to offer best efficiency and no wastage. These drop-off
points can’t be found inside or outside. They can be separated based on the
following grounds:
-
Size
-
Wet
and Dry
-
Recyclable
and Non-Recyclable
It is important
that these drop off points are sealed as to ensure that the garbage is not
smelly and hence ensures clean surroundings as compared to the original style
of collecting garbage (through dumpsters and drainages)
Figure 2. Difference in garbage
collection points
OLD
Figure 2. (a) Traditional waste
collection points
Reproduced from The Guardian Gowthorpe,
A. (Photographer) (2012).
NEW
Figure 2. (b) Pneumatic
system collection points.
Reproduced from The
Architects Newspaper Envac. (Photographer) 2012
Vacuum Air
ducts
These
are the ducts that help in the transportation of the waste from the garbage
drop off points till the refuse containers. Vacuum systems first originated in
the United States to collect hospital laundry during the 1950’s. (Luiten P.,
1976). They are made up of lateral and vertical metal sheets chutes, where the
air intake is at the top of these chutes.
Since these are gravity-type chutes, as soon as the waste is dropped in,
it automatically falls down to the bottom of the pit where a collection valve is
open. This collection valve then connects to the mainline where there is a high
intensity airflow, which draws the garbage through the main line. For the
vacuum air ducts to be effective, certain criteria must be fulfilled. For
example, the number of ducts in a system, the total capacity of waste the
system can hold, the distance along which the system is spread, etc.
Figure 3. The large
interconnected underground pipe system.
Reproduced from Nederman (2013)
Large Refuse
Containers and Final Transportation
The large refuse
containers can be found at the end point of all pneumatic systems. It is the
collection point of all the refuse. Usually large in size and kept in locations
where they can be loaded and unloaded easily, and large space for them to be
stored. The cross section of these refuse containers are square in shape to
provide maximum surface area to store the waste. The waste can then be
transferred to the vehicles, through bypass pipes, or the trucks can transport
the entire container to
the
final disposal site. In the case of recyclable waste, these containers can be
present at the sites where the waste is recycled within the city. All the waste
can be channeled to these locations. However, when it comes to disposing other
solid wastes, transportation of the containers will be needed to the disposal
sites, as they present outside the cities in large open land areas.
Currently, the
pneumatic waste collection systems are being implemented in over 30 countries,
but only in urban areas and not on a large scale.
Figure 4. Transportation trucks used in the
final transporting of the waste.
Reproduced from: Autoevolution
(2010)
1.6 Future
considerations
There is an
increasing awareness about the importance of effective waste management, and
hence many companies and countries are moving towards implementing the
pneumatic waste collection systems. As development projects are rising in
Europe and Asia, countries like Japan, Taiwan and Hong Kong are leading the way
for implementation. The city of Helsinki,
Finland is planning to include this system in its latest development
project- the construction of Jätkäsaari residential area
This system is
not only being implemented in new upcoming urban areas, but also in historical
and cultural areas such as the famous city of Leon, in Castilla y Leon (Spain).
(Gonzalo B., 2002). Due to the solid waste being a huge
problem, which is interfering with the preservation of this historical site,
the government of Spain is now looking to install this system.
As far of the
design of the system goes, the new Movac system is said to contain two new
compartments, third
generation mobile vacuum vehicle, the VL-5, and the patented screw tank
concept. This allows the emptying time to be cut in half and the collection
capacity doubled. This increases the scope for liquid and wet waste and well.
With this type of system, we would be able to segregate the liquid waste, only
enlarging the horizon of this system. All these innovations in the technology
will definitely help the AVAC become more sustainable, eco-friendly and not to
forget, efficient.
The leading
companies that are into this technology are TransVac Solutions, USA (inventor
of the system), Envac, Sweden and Ecosir, Finland. Apart form these, there do
exist many more companies that are investing their time and money into research
and implementation of this technology. (Kwang B.L., 2004/2005).
Figure 5. The new
Movac System.
Reproduced from:
Cleanvac (2012)
1.7
Conclusion
The pneumatic
waste collection system has a bright future laid out in front of it. This
entire paper has clearly outlined the scope this system has in bringing about a
revolutionary change in our waste management techniques. Some of the major
advantages of this system would be that we would be dealing with a fully
automated and mechanized system, including hardly any manpower in the entire
process. This increases the efficiency and ensures full-time functioning. The
limited manpower that would be necessary will be deployed only at a supervising
stage, and no less. This machine offers high safety standards and poses no
direct threat as an incinerator would. The complete sealing of the system
ensures no smell and odor to attract rats and other pests. Not only does this
improve the aesthetics of the surrounding environment, it eradicates all
possible infectious diseases increasing the health standards and sanitation
among the population.
This system would wipe out the need
to throw solid or wet waste into water bodies, thereby improving water quality
and ensuring safe drinking water for everyone. With everything being automated,
there would be no need for the daily garbage trucks, thereby reducing sound
pollution in the cities. This would overall ensure quiet, clean and hygienic
neighborhoods, with more free space to concentrate more on social and cultural
activities. The amount of land resources this system can help save is enormous.
The largest impacts however, will be the benefits this system has to offer to our
environment. Lesser noise pollution, contamination, air pollution and
destruction. Cleaner and healthier environments will promote social, cultural
and economic growth among countries.
However, every
coin has two faces Sides. With the numerous benefits that this system does
offer, we must understand that there are certain drawbacks as well. For
starters, it has large start up costs, making it an expensive investment which
most less economically developed countries would not be looking to adopt. Also
in countries, which are densely populated like China and India, it will be
extremely hard to implement these underground systems, as it would include lots
of construction, effort, time and money.
Most
importantly, this system does require some amount of expertise and knowledge as
far as research goes. Many developing countries may not have access to these
types of resources in the immediate future.
However, this is
an investment that has greater pros than cons. It is an investment to a
brighter, healthier environment. It is one step closer to saving our natural
resources and preserving our Earth.
The
AVAC system could be the possible solution to a large number of our problems.
Though it will require thorough research and heavy investments, it is best if governments
around the world begin to consider this method as being the best technique in
effective waste management.
In reference to
sustainability,
"We do not inherit
the Earth from our Ancestors, we borrow it from our Children"
-Ancient
Indian Proverb
References