A container Identification System

Waste management costs are escalating across Europe and this trend is putting more and more pressure on municipalities' budgets. There are four main reasons for this:

One possible way to handle this problem is to implement an identification system. The system automatically identifies individual waste containers during collection. This allows data exchange, transmission and processing for:

How An Identification System Works

Each container is equipped with a microchip containing specific information as to its identity and where it is located.

Every time it is lifted

Information contained in the chip is read by a system installed on the lifting device. The containers are weighed at the same time and the weight of the waste emptied is associated with the container that has been identified.

All the data is systematically and automatically recorded by the on-board computer installed in the collection vehicle's cab. Elements relating to the collection (data, presentation counter etc.) are sent to the microchip and stored in the memory. The total process is illustrated in Figure 1 and the stages are described in the following sections.

Figure 1. A diagram of the complete process

On each collection round

The link between the chronotachograph and the on-board computer gathers different elements relating to the collection rounds, i.e. times, mileage, mileage from the depot to the beginning of the round, number of containers emptied, etc.

After the collection

The on-board computer's removable tape is transferred to the garage. All the information collected is then sent to the central computing system via a specially installed line.

Exploitation of the data

Each participating local authority service is directly connected in real time to the central computing system where all the data is stored.

The software has two main functions:

Equipment

The wheeled bin

Figure 2. The wheeled bin and the placing of the
microchip and the bar-coded address label

Each wheeled bin is equipped with a microchip and an address label with a bar code (Figure 2). The chip is fitted into a standardized position under the flange. It can be used with a front or side grip. The address label is fixed on the back of the bin.

The microchip

The chip is encased in a plastic, weatherproof cylinder 29.7 mm in diameter and 14 mm thick. Its position under the flange of the bin makes it practically invisible, thus decreasing risks of malicious intent. It can only be removed with a special tool.

Functional Presentation

The microchip used operates in Read-Write remote mode and contains an EEPROM type memory. The memory is read and written by high-frequency communication without any physical contact. The main characteristics of the microchip are given in Table 1.

The microchip has a unique identification number. Information concerning the identification of the container is loaded into the chip's memory when it is initialized. Information concerning the presentation of the bin is automatically updated at every collection. Results relating to the last 32 collections are recorded in the unit. Information is kept for ten years.

Reliability - Regulations

The principle of exchanging information by radio waves enables the electronic components to be completely isolated from their surroundings as they are enclosed in a plastic case. This approach has been carefully selected for the waste disposal environment to protect the chip from dirt, moisture and chemical agents (protection factor IP 67).

The chip is also protected from shocks and vibrations that occur when the bins are handled and collected. The chip operates within a temperature range from -30°C to +70°C.

The electronic circuit integrated in the chip is a transponder, which works by induction when the chip is placed in front of the scanning device. The chip does not contain a battery.

The wave frequency and the low power used mean that the microchip identification system complies with current telecommunication regulations.

On-Board Systems

The on-board systems enable collections to be permanently and automatically monitored. They consist of three main interconnected elements (Figure 4):

Figure 4. The on-board systems

The Identification System

The identification system consists of the following elements:

The scanning sensors are two aerials installed on the lifting-device comb. They enable the chip number to be automatically read as soon as the container is placed on the tipper. The identification system is perfectly adapted to the waste environment.

Three sensors that detect the bin's presence are installed on the lifting device. When they detect the presence of bins, they send information to the tipper as to its operating mode.

There are also lifting and emptying sensors at the rear of the vehicle. These inform the on-board computer that the bins are correctly positioned and raised.

The Weighing System

The system automatically weighs the refuse containers placed on the collection vehicle's lifting device.

The weighing cells (strength sensors) are installed on the lifting device. Each cell is fitted between the comb and the rest of the lifting device body. It transforms the mechanical force that the bin exerts on the comb into an electrical signal. A calculator to work out the weight of the bin collected then exploits this signal.

The system works on a double-weighing principle. The bin is weighed when it is raised (full) and again when it is lowered (empty). For each weighing cycle, several samples are taken into account. The calculator thus establishes the net weight of refuse collected.

Weighing is dynamic and the system installed does not modify the lifting device cycle. The weight collected is automatically associated with the bin's identification number and then recorded.

The On-Board Computer

The on-board computer has been specially developed to record data in the field of road haulage. It consists of a membrane keyboard and an LCD screen. It is installed in the cab of the vehicle next to the driver. It can be taken out of its bracket and carried by hand.

In association with the identification and weighing system, the on-board computer records the information contained in the chips and the net weight of the bins collected and therefore creates a refuse collection file.

The connection to the vehicle's tachometer records information concerning the vehicle, i.e. the circuit number, the time the collection started, the time the collection finished, the mileage covered for each vehicle during the collection, the mileage covered from the depot to the start of the collection round, etc.

Data collected is stored in the removable cartridge in the on-board computer. This cartridge enables data to be transferred between the vehicle and the garage. It is personal to the driver.

The collection management unit

This unit is integrated and performs the following functions:

Gathering And Processing Information Recorded By The Refuse Compactor

When the identification system is installed on the vehicle, all the containers presented during the collection are identified. The vehicle records the following information:

Analysis Of The Collection Rounds

For each collection circuit on a given date or over a set period, the following information can be displayed or issued:

Analysis For Each Waste Producer

The following information is available:

Individual billing

An identification system is a precise tool that can reliably identify everyone involved in waste production, with no exceptions. The database can be regularly and quickly updated to show, for example, whether the waste producer moves address, if the containers are removed or replaced and if more are needed.

A tariff mode can be based on two methods, the number of times the bin is emptied in a given period or the weight of waste collected. The system provides:

Real-time equipment management

Detailed research that should be conducted on households before installing containers achieves two objectives:

All these parameters are collated and downloaded onto a main server, which can be accessed at any time by the municipality.

This easy access facilitates the exchange of a variety of data, to indicate:

A Successful Experience

The following are the effects that have been achieved in Huissen in The Netherlands:

Conclusion

An identification system encourages each householder both to generate as little waste as possible and to participate in selective collection programmes.

With a billing charge directly linked to the volume of waste produced, individual billing systems have a rapid influence on the amount of waste produced by householders. Consumer habits change and priority is given to using recyclable packaging. People make a conscious effort to produce less waste.

François Salmon is in the Marketing Department at Plastic Omnium Urban Systems, 1 rue du Parc, 92593 Levallois Perret Cedex, France. Tel.: +33 1408 76400 Fax: +33 147304 253