Ref Manual Servicing Technicians Unit 3 (Refrigerant Management)

3.1. Management plans

Refrigerant management has been done in two levels: at a country government level and at installation/application level. Strategies for refrigerant management have been developed at a country level as an action

of the Montreal Protocol implementation in developing countries by UNEP and other implementing agencies in conjunction with National Ozone Units (NOUs) and other governmental institutions.

The Multilateral Fund (MLF) assistance to Article 5 countries in the refrigeration servicing sector started in 1991 when projects for training service technicians and recovering and recycling chlorofluorocarbon (CFC) refrigerants were first approved. In 1997 these standalone projects were replaced by Refrigerant Management Plans (RMP). Refrigerant management is an approach to optimising the use of available refrigerants in the existing equipment and minimising the demand for virgin refrigerants for servicing through technical and regulatory measures. This is aiming to allow the appropriate operation of the equipment throughout its lifecycle at reducing harmful impact to the environment resulting from the emission of refrigerants.

The conditions and resources allocated for the RMPs have been adjusted from time to time. After the RMPs, projects called Terminal Phase-out Management Plans (TPMP) have been developed. Under a TPMP, a country receives funding for a full phase-out of CFC consumption on the understanding that no further funding will be requested.

The majority of the RMPs and TPMPs are carried out in low-volume consuming countries (LVC) with 75%–100% of the CFCs consumption in the servicing sector. Since 2007 with the approval of the acceleration of the phase-out of hydrochlorofluorocarbons (HCFCs), the Multilateral Fund for the Implementation of the Montreal Protocol is supporting the development of HCFC phase-out management plans (HPMPs) in developing countries.

Refrigerant management plans for CFCs (RMP)

An RMP is a comprehensive strategy to phase out the use of ozone depleting refrigerants used to service and maintain refrigeration and air conditioning systems. It may include actions to reduce ODS consumption and emissions, reduce the need for further servicing by controlling new installations and restricting imports of equipment that depend on ODS for their functioning, and promote retrofitting and replacement of existing equipment. Regulations, economic incentives and disincentives, training, and public awareness activities are some of the tools used to achieve these goals.

The successful implementation of RMPs requires the coordination of activities in different ODS-using sectors, including:

•      Manufacturing

•      Servicing

•      End-users sectors

•      Regulatory and trade controls

•      Economic incentives and disincentives

•      Training on good practices in refrigeration for service technicians

•      Training for customs officers

•      Establishing recovery and recycling programmes

•      Public awareness campaign.

Terminal phase-out management plan for CFCs (TPMP)

The TPMP contains the Compliance Strategy and Action Plan for the elimination of the use of the CFCs controlled under Annex A Group I of the Montreal Protocol, until their final phase out on 1st January 2010. It also contains follow up actions, to ensure the necessary compliance monitoring and reporting.

HCFC phase-out management plan (HPMP)

The HPMP includes undertaking a comprehensive survey of the refrigeration and air conditioning sector and all sectors and sub-sectors that use HCFC. It describes the overall strategy that will be followed by the country to meet the complete phase-out of HCFCs. This includes policy instruments to reduce supply of HCFCs, and a plan for implementation of alternatives for new and existing equipment and products. The HPMP needs to take into account the climate impact of the alternatives, and should be coordinated with chemical management and energy policies.

 

To implement a strategy for refrigerant management in a country, it is essential to develop actions at field installations level. Technicians in developing countries have a very important role helping their countries to implement plans to phase-out CFC and HCFC refrigerants, and also to decrease emissions of hydrofluorocarbon (HFC) refrigerants.

This can only be achieved with the adoption of good practices in refrigerant management, in handling and working with refrigerants. This is the role of refrigeration and air conditioning (RAC) technicians, and this is the focus of this manual.

Recovery cylinders

Recovery cylinders are specifically intended for refrigerant that have been removed from refrigeration systems. The recovered refrigerant can then be re-used or sent for reclamation or disposal. The construction of the cylinders is normally very similar to a conventional refillable cylinder, except for two differences: one is that the cylinder valve has the refrigerant filling port enabled, so that refrigerant can be easily fed into the cylinder, and the second being the external marking. The cylinder shoulder and upper part is normally painted yellow, with the remainder of the cylinder body painted grey colour code is also applied to cylinder to indicate the type of recovered refrigerant, as shown in the illustration.

It is important to ensure that the recovery cylinder is only ever used for one type of refrigerant. This rule should be followed for two reasons: first, if different refrigerants are mixed, it may not be possible to separate them again for re-used, and secondly, mixing two or more refrigerants can result in a pressure that exceeds the pressure of either of the refrigerants added into the cylinder.

For refrigeration technicians using recycling machines, it is suggested that the refrigeration technician utilise a ‘CLEAN’ recovery cylinder for recycled refrigerant and a ‘DIRTY’ recovery tank for recovered, but not recycled refrigerant. Marking the recovery tanks as clean and dirty will avoid contamination of otherwise clean refrigerant by putting clean refrigerant into a recovery tank that once held dirty refrigerant

In the end, one can say that we should apply to refrigerants a general concept that starts to be used

in waste management is the 4R principle: Reduce the use, Recovery, Recycling and Reuse. This can

be achieved through technology development, making systems more hermetic and with lower refrigerant charge and through good practices on refrigerant management. The last is refrigeration technicians’ task and this section provides some guidance on that. We start with handling of refrigerants.

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Handling of refrigerants

Below are presented some aspects of the management of refrigerant cylinders. Specific considerations about safety and care precautions concerning the manipulation and direct contact with refrigerant itself are

presented in	Chapter 6	4

Refrigerant cylinders

Refrigerants are packed in both disposable and returnable (refillable) shipping containers, commonly called “cylinders”. Disposables are manufactured in sizes from 0.5 litres to 22 litres capacity (corresponding to approximately 0.5 to 25 kg of CFC, HCFC or HFC refrigerant). They are considered pressure vessels, and in most countries therefore are subject to national regulations.

Containers are designed for pressurised and liquefied gases, and are labelled accordingly. Some refrigerants are gases at atmospheric pressure and room temperature, and are therefore transported and stored as liquefied compressed gases in pressurised cylinders. Other refrigerants are liquids at room temperature and contained in drums, barrels or other standard containers.

Numerous regulations are in force worldwide for the manufacture, handling and maintenance of pressurised containers. Cylinders are manufactured to specifications established by countries regulatory authorities.

There are different types of cylinder:

Disposable and non-refillable cylinders	4
Refillable cylinders	4
Recovery cylinders	4

Normally, each cylinder is equipped with a safety-relief device that will vent pressure from the cylinder before it reaches the rupture point, in the event of, say, overheating. When temperatures increase, the liquid refrigerant expands into the vapour space above the liquid causing the pressure to rise gradually as long as a vapour space is available for expansion. However, if no vapour space is available due to an overfilled cylinder and no pressure-relief valve is available, the liquid will continue to expand with no room for the expanding liquid and will result in extremely high pressures with the consequence

of the cylinder rupturing. When the cylinder ruptures, the pressure drop causes the liquid refrigerant to flash into vapour and sustains explosive behaviour. The rupture of a refrigerant cylinder containing liquid refrigerant that flashes into vapour is far worse than the rupture of a compressed-air cylinder of the same pressure. The next pages include information on cylinder management plans.

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Disposable and non-refillable cylinders

Available on the market are a type of cylinder called “non-refillable” or “disposable” cylinders. These are sometimes used where the supply infrastructure is less comprehensive, and it is less costly for refrigerant suppliers who may expect their cylinders to become lost. From both an environmental and safety perspective, the use of disposable cylinders is considered to be very bad practice.

These containers are generally discharged after use, resulting in a lot of refrigerant being released to the atmosphere. Furthermore, there are often attempts to re-use these cylinders (for example, through brazing new valves onto them to enable re-filling with refrigerant), despite such practices being forbidden. Also, they tend to be manufactured from thinner metal than the conventional, re-usable cylinders, rendering them more susceptible to rusting and mechanical damage over time. As such, their use is not recommended under any circumstances.

In fact they are already prohibited in many countries, such as the European Union member states and Australia and Canada. Other countries are also working to implement similar rules. Mandating the use of returnable, refillable containers was implemented as a key measure to reduce GHG emissions by eliminating the possibility of the eventual release of the residual product that unavoidably remains in disposable refrigerant containers. These regulations had support from the major refrigerant manufacturers and industry trade associations.

If a disposable cylinder has been used, before disposing of it, it should be properly emptied. This requires the remaining refrigerant

to be recovered until the pressure has been reduced to pressure of approximately 0.3 bar (absolute). The container’s valve must be closed at this time and the container marked as empty. The container is then ready for disposal. It is recommended that the cylinder valve should then be opened to allow air to enter, and the cylinder should be rendered useless (with the valve still open) by breaking off the valve or puncturing the container. This will avoid misuse of the container by untrained individuals. Used cylinders can be recycled with other scrap metal. Never leave used cylinders with residual refrigerant outdoors where the cylinder can rust. An abandoned cylinder will eventually deteriorate and could potentially explode.

Refillable cylinders

Refillable cylinders are the standard receptacles available for the storage and transportation of smaller quantities of refrigerant. They normally range in size from about 5 litres to 110 litres (approximately 5 to 100 kg of CFC, HCFC or HFC refrigerant). The cylinders are normally constructed from steel and have a combination valve, with separate ports for refrigerant removal, refrigerant filling and

a pressure relief device. The port for refrigerant filling is normally locked so that only the refrigerant supplier can gain access. Some cylinders also have two separate removal ports: one for liquid and another for vapour, if the cylinder is fitted with a dip-tube. There is usually a metal collar around to the top of the cylinder to protect the valve from mechanical damage. Both the cylinder itself and the valve are usually subject to national regulations for their design, fabrication, and testing.