Plastics recovery manual/Chapter 3: Collection/Collection systems

Collection systems[edit | edit source]

Sensibilisation[edit | edit source]

Experience has shown that the recycling of plastic waste is an activity that can be profitable. This profitability is often compromised when the recycling center must take charge of the own sensibilisation of people regarding the problematic of waste. Sensibilisation requires substantial resources that must not be neglected. Generally, it is advised to separate the two activities and to be imaginative about how to sensibilisation is done: financing research parallel to those funding the project, involvement of local authorities or associations sensitive to the environment, use of communications media (media), ...

a. Sensibilisation of collection agents The sensibilisation of collection agents is essential. They are in fact directly in contact with waste producers and thereby contribute to their sensibilisation. Moreover, they are the ones who handle the waste. They can then judge the quality of the sorting. These agents may be part of the recycling center, work for their own account or belong to an existing collection network. Their sensibilisation can be done through training sessions. They will notably learn:

• Sensibilisation of their role in industry development;
• The extent of the damage plastic waste can do to the environment, but also the benefit that be provided for it;
• To differentiate the recyclable plastics amongst each other and evaluate their quality (fouling, soil, ...);
• To sensibilise the population of the problem of plastic waste.

Do not hesitate to explain in detail the central activity, and the problems encountered throughout the recycling process, especially when the quality of the waste is also put into consideration. It is also important to perform debates to know everyone's problems and find solutions adressing everyone's interests.

b. Sensibilisation of waste producers Education and sensibilisation of the inhabitants or waste producers to separate the plastics from other waste is not done overnight. Indeed, the audience often has other concerns as sorting their daily waste. It is nevertheless important that sorting is done; the supply of plastic recycling centers depend on it. Women and children are most susceptible to environmental problems. Women are the primary concerned ones because it are them who often dominate the daily household tasks, and therefore the cleanliness and waste. Children are more engaged in separate collection from a personal motivation (see Table 3.5), which will bring them an intresting little income. Furthermore, the sensibilisation from an early age has long-term effects.

Communication channels for a good sensibilisation are numerous. The main thing is not to lack imagination. As examples, here are some ideas:

• Articles in local newspapers, posters in the streets;
• Radio and television commercials;
• Meetings in associations sensitive to the environment (including women's associations);
• Fun activities in schools (drawing contests, games on the theme of waste ...);
• Message at religious events, sporting, cultural, ...
• Organized visit to the recycling center for stressing the importance of sorting at the source, ie by the people.

During these campaigns, we seek to empower collection agents that stress the importance of their activity for the safety of their neighborhoods. Sensibilisation is an activity to be renewed perpetually. Good habits get lost quickly. It is always necessary to find new ideas.

Selective collection systems[edit | edit source]

Collection systems are "the way how waste moves from the inhabitant or producer of waste to the collection service".^[1] In the case of the collection of plastic wastes, we speak of separate collection, ie which aims to collect only certain types of waste. The selective collection can be fit into an existing collection system or, conversely, be organized in parallel to it. Before running through the different collection systems that can be implemented, it is important to make some recommendations:

• No ideal collection system exists. Each case needs to be studied to respond to the local context and project objectives. The best collection systems are those that are customised and not those who were simply copied.
• Equip adapted means. In the collection, it is indeed tempting to use so-called "modern" means but these often do not meet the conditions of countries with low and medium incomes. Also, the purchase of expensive vehicles, but immobilized ones because they are not appropriate to road conditions or because the price of maintenance is too high do not make smart investments. Instead, it is often preferable to use methods which use a greater human capital and base technologies better adapted to the conditions.
• For reasons of workhygiene, it is better to focus on maximizing the "Upstream collection", that is to say, at the inhabitant rather than recovery in streets and landfills. Wastes have indeed less soil, and are therefore less fouled. Moreover, washing and sorting will be facilitated.

a. Selective collection inserted into an existing collection network Table 3.4 shows the most common waste collection systems (H.C. Haan, 1999). For each system, some suggestions are proposed to insert a selective plastic waste collection.

System	Description	Selective collection	Advantages	Disadvantages
Shared	People or waste producers can bring their waste when they so wish.
Deposits on specified places	Inhabitants and other waste producers deposit their waste at a specific location or a masonry enclosure where they are transported.	Possibility to limit a part of the enclosure reserved for waste plastics.	Little investments	Difficult loading. The sorting is little controlled. The plastics are often mixed with other waste, thus soiled. Theft of waste plastics.
Shared container	Residents and other waste producers bring their waste to the container which is frequently moved or emptied.	A container can be reserved to only hold plastic waste.	Possibility to use closed containers that limits thefts.	The sorting is little controlled. The plastics are often mixed with other waste. Fairly expensive.
Individual	Inhabitants and farmers keep their waste at home until the collection
Block collection	The garbage collector waits at the specified places where the inhabitants bring their waste to the collection cars.	The garbage collector can recover the plastics separately and encourage residents to separate their waste. For this, the vehicles must be equipped with a compartment for plastics.	Inexpensive. Good sorting control. Possibility of sensibilisation and payment.	Requires a member of the family to be on-site and thus moves itself.
Sidewalk collection	The waste is deposited in front of the houses and placed in a vehicle or investigated and collected by a garbage collector.	Residents can deposit the plastic waste separatly. These are separately collected.	Convenient for the inhabitants.	Storage of the waste in the street, where it fouls and mixes.
Door-to-door collection	The garbage collector goes to the inhabitants and waits until they bring him the waste.	The inhabitants can deliver their plastic waste separately. The garbage collector will deposit the plastic waste in a container of his vehicle intented for the plastics.	Possibility of sensibilisation and payment. No waste is stored in the street.	Requires the presence of an inhabitant. Little suitable for large buildings.
Collection in the dooryard or garden	The garbage collector enters the property to remove the waste.	Residents can deposit plastic waste separatly. These are collected separately.	Convenient for inhabitants. No waste stored in the street.	Requires some trust between the garbage collector and the inhabitants.

Table 3.4: Insertion possibilities of a selective collection into existing collection systems

The "block" and "door-to-door" collection gives the best results because they bring together inhabitants and the collection agent. This may allow sensibilisation to improve the quality of the supplied plastic waste. It is not always possible to change people's habits by sensibilisation to separate the plastic waste from the other waste. Nevertheless, the collection agent can always sort the waste he picks up daily himself, and this irrespective of the collection system in place. The plastics thus recovered provide him an additional financial return.

Example of a selective collection in Cairo (Egypt) The case of the scavengers in lower Mokattam is one of the most famous in the collection. This neighbourhood of Cairo lives mainly on the collection and recycling of waste. Every day, the trash pickers go into the richer neighborhoods off the central city to collect the garbage (door-to-door, dooryard or garden collection). They divided themselves into neighborhoods buying a collection right and take the waste from their home to dispose of them. The sorting is usually a family affair. The waste is separated by the type of material (organics, wood, cardboard, paper, metals, plastics, ...) but also according to their destination. Also, the plastic waste is divided by color, objects (cans, jars, shoes, ...) and so on. Regarding these different kinds of plastics, there is a terminology that has been created. They speak not of PP, PE, PVC, ... but of hard plastics, soft, tender, ... All obtained objects are sold to recycling workshops or neighborhood intermediaries who undertake the task of recycling them. It is not uncommon for parts of this waste to be directly sold to official factories. Thus, the route from the informal sector to the formal sector is quite common.

b. selective collection established in parallel Some neighborhoods do not always dispose of domestic waste collection approaches or, if they exist, they may not be well enough structured so as to be able to introduce a separate collection of waste plastics. In these conditions, it is necessary to establish a separated collection system for plastic waste. The different options are described in Table 3.5.

System	Description	Advantages	Disadvantages
Door-to-door collection	Collection agents regularly visit the inhabitants or waste producers who wish to get rid of their plastic waste. These collection agents may either be employed by the recycling center or be paid by it according to weight. In some countries, the collection agents pay the inhabitants for the received plastics per kilogram.	Possibility to sensibilise the inhabitants and the waste producers. The collected plastic waste is often of good quality.	Slow job requiring a large number of agents. Requires the presence of inhabitants when the collection agents pass by.
Voluntary contributions	Closed containers are placed at strategic locations in the area targeted by the project: major intersections, near markets, ... The inhabitants or waste producers come to dispose of their used plastics. Containers are regularly removed or emptied.	Cheap system.	No control over the quality. Much other wastes are generally found in these containers (thus fouled). Difficult to implement sensibilisation.
Contribution motivated by payment by weight	Collection agents regularly visit strategic locations called "collection points". They pay the people or waste producers according to the weight of the given plastics. Often, young people perform their own collection from door-to-door and bring the received plastics to the collection points.	Control of the quality of the received plastics. The waste can be paid according to their type if they are already pre-sorted according to the type. A good sensibilisation is then required.	This system can be costly if the collection agents are not adequately trained tn the recognition and the prices of the plastic waste.
Sorting center	These centers typically sort municipal waste into compost. An arrangement is made with the leaders of the sorting center to ensure that they also sort the plastic waste. The collection agents regularly visit the center to collect the plastics and may also pay by weight.	The waste is already gathered in a place. Sorting centers are often interested in getting rid of this non-recycled waste.	The plastic waste is often very soiled and fouled by other wastes (metals, paper, cartons, ...)
Dumpsite sorting (photo 3.12)	The sorting is done when no selective collection system has been established. Sorting is then performed by people who earn their living bringing the plastic waste to the recycling center (or collection points). They are paid according to the weight of the plastics.	The waste is assembled in a place.	Precarious (unhealthy) working conditions. This system is to be avoided at all costs.

Table 3.5: Possibilities for inserting a collection system in parallel to existing collection systems

When a voluntary contribution collection system is proposed, it is sometimes necessary to use closed containers so as to avoid any risk of theft of the plastic waste. The figure below illustrates a proposed solution for Kinshasa. This is an oil drum above which two steel pipes are welded at an angle. An opening system with a padlock allows collection agents to recover the plastic waste during their daily rounds. The cost of manufacturing this type of dumpster is 75€ (Kinshasa, 2003).

Example of payment motivated collection in Yaounde (Cameroon) In Yaoundé, specifically in the area of Etoug-Ebe, the NGO CIPRE (Centre International de Promotion de la REcuperation) has established a selective payment motivated collection system where the payment is done according to weight. Every fortnight, a dozen collection agents serve the 50 collection points located in this neighbourhood of about 100,000 inhabitants. Their role is to collect the plastic waste, pre-sorted, weigh, and package them and pay the inhabitants who bring them.

This system allows to collect ten tonnes of waste plastics per months, or one tonne per collection agent. In addition, it offers the advantage of a certain flexibility. Indeed, by adapting its compensation schedule, the IPRC can recover the plastics it wishes. So, the PE bottles are paid 25 CFA/kg (0.04 €/kg) while a kilo of PVC soles can reach 100 CFA (0,16 €). This system is not exploited to its full potential as an objective of CIPRE is to reduce the impact of plastic waste on the environment.

Example of a mixed system in Bangalore (India)^[2] India is one of the most active countries in the recycling of plastic waste. In the city of Bangalore, a dual collection system exists. First, 3000-4000 collection agents perform a door-to-door collection and buy plastic waste from the inhabitants. These buyers collect on average 10 kg of plastics per day for 25 days a month. This source collection can obtain waste quality plastics with little fouling, with an intresting market value. On the other hand, 25,000 people sort on the various dumpsites of the city. They extract 15% of the recoverable material of which 4% of plastic waste. On average, each sorter recovers 8 kg of plastic a day and works 20 days a month. The most fouled waste is resold at lower prices than those collected at the source.

'c. Frequency, transmission and transfer Besides the type of collection system in place, it is important to consider three parameters which are the frequency of collection, transport and transfer.

1. The collection frequency of plastic waste is assessed during the implementation of the collection system but must be regularly updated. It is charecterized by various factors such as:

• The quantity of accumulated waste with the inhabitants or in the reunification points. A too infrequent collection causes accumulations of waste and therefore significant nuisance: odor, visual pollution, risk of being eaten by livestock, ... this may discourage the sorting and all efforts in sensibilisation will be destroyed.
• The quality of plastics, which is directly related to the storage time of the waste sorted by the inhabitant, in the streets or in the landfills.
• Habits of the local community. In some communities, waste is collected every day. A less regular collection of sorted plastics can cause a blockage and become irreversable.

The frequency of collection is thus an excellent indicator of the quality of the collection service. It is necessary to make every effort into make it as high as possible.

1. We can not repeat it enough: "Transporting is expensive! And transporting plastic is even more expensive given their low densities (between 0.9 and 1.4, but the density in bulk rarely exceeds 400 kg/m³). It is therefore needed to be very wary about this aspect of the project. To do this, some advices may be followed:

• Shorten up the routes as much as possible, including placing the recycling center as central as possible in the area but also by organizing the pick-up smartly.
• Use of cheap transport, adapted to the local environment
• Atleast condition the waste to densify the content of the collection vehicles. For this, it is sometimes advisable to already perform an initial cut up before placing it in the vehicle.

The choice of the vehicle is very important. There are countless projects that have opted for unsuitable transport means and of which the vehicles (often very sophisticated) are found to stop due to fuel exhaustion, breakdown, unobtainable parts, ... It is therefore essential to thoroughly research the local situation before investing. The volumes of waste to be transported and the distances are known before the evaluation of the deposit made on the area. The table below shows, in order of increase in investment cost, the various means of transport traditionally used to collect urban waste.

Vehicle	Volume	Range	Accessibility	Remarks
Handcart	0.25 to 1 m³	~ 1 km	Everywhere	Cheap, no negative effects on the environment
Tricycle with pedals	1.5 m³	1 to 3 km	passable trails	Faster, no negative impacts on the environment, lifetime sometimes limited.
Animal-pulled cart	1.5 m³~7 km	passable trails of a with larger than 2.5m	Greater investment cost (purchase, nutrition and animal care). Little impact on the environment, except for the excrement.
Small motor vehicles (motorcycles, tractors, freight motorbike, ...)	1.5 to 4 m³	Up to 10km	Passable trails	Lifetime often limited because they are pushed to their maximum capacity. Fuel expenses.
Pick-up	3 to 6 m³	Very far	Passable roads and tracks	High investment cost (purchase, insurance, fuel, maintenance, ...)
Truck	Up to 12 m³	Very far	Passable roads of a minimum width	Very high investment cost, expensive and sometimes difficult obtainable spares, great delay of delivery for these parts, ...

Table 3.6: Types of collection vehicles

Accessibility is a qualitative type of data. The streets in some neighborhoods are too narrow, congested or unpassable for large vehicles to pass. We evaluate the accessibility by identifying the streets of the area and classifying them according to their ease of access:

• For large vehicles: truck, pickup
• For light vehicles: pickup, van, small motorized vehicles, ...
• For non-motorized vehicles: freight motorbike, cart, carts, ...
• Only on foot.

1. The notion of transfer occurs when the collection system in place requires different means of transport. We then talk of different levels of collection:

• The primary collection. This is the collection at the place of waste production, notably at the inhabitants, at the enterprises, at the merchants, ... When travel distances permit and when the quantities of waste to be collected do not exceed the capacity of the used vehicle, the waste is directly transferred to the recycling center.
• The secondary collection. The distances from collection sites to landfill or recycling center is sometimes too long, notably for cart- or freight-motorbike-type vehicles. It is better to conduct a waste collection run and then transferring the collected waste into a larger vehicle which is better suited for long trips. We call these stopovers "transfer sites".
• The tertiary, quaternary, ... collection. And so, we can multiply the methods of transport and the transfer sites. The waste may also be transferred to sorting centers. The recyclable matter is then transported to the recycling centers while the leftover waste is going to the landfill.

The main thing is know whether to proceed from a primary to a secundairy waste collection and the costs of this transfer must be evaluated according to the material used in each phase.

Moreover, we must carefully determine the best method for unloading the primary vehicles and the loading of the secondary vehicles. For this, there are two ways in which to proceed:

• The direct transfer consists of simply loading the waste by hand or by using tools from the primary or secundary vehicle. This technique, unfortunately too often used, is very inefficient and not hygienic. The transfer is very slow. We are wasting time (and money) because we need to synchronize the vehicles. The environment is often polluted by any waste falling off during operations.

• The transfer at two levels consists of raising the primary collection vehicle sufficiently high so as to be able to dump the waste into the vehicle or in a secondary container using the force of gravity. This can be done by constructing ramps, pits, or simply by using the natural elevation of a slope. The transfer is so much faster and more hygienic. The economic performance is obviously much greater.

Note: A too gentle slope takes up a lot of space. A too steep slope limits the weight contained in the primary vehicle.

To learn more about waste management: H.C. Haan, A. Coad, I. Lardinois, 1999, Gestions de déchets municipaux: Engager des micro- et petites entreprises, translation by F. Weijters-Bage, SKAT, Switzerland. Book intented to managers of municipal solid waste who seek to improve their service or save money. He answers the questions "why" and "how" to engage small groups in community-based collection of solid waste from streets, households and businesses. The authors look mainly on the situations encountered in countries with low and medium incomes and derive many lessons from experiences that were made in Latin America, South-East Asia and Africa. This book can be obtained at: Intermediate Technology Publications Ltd. 103-105 Southampton Row, London WCIB 4HH, UK tel. : + 44 171 436 9761 fax. : + 44 171 436 2013 e-mail: itpubss@gn.apc.org website: www.waste.nl Website of the dutch ngo WASTE; which specializes in the management of solid waste in developing countries. Some publications (in English) can be directly downloaded from the website (Integrated Sustainable Waste Management, UWEP). Others may be ordered by contacting Verele de Vreede, information officer (fax: + 31 182 5503 13 e-mail: vdevreede@waste.nl). The prices vary between 5 and 25 €.

References[edit | edit source]