Reproduced, with permission, from:
United Nations Environment Programme. 1991. Controlled substances. Chapter 2 in Montreal Protocol on Substances that Deplete the Ozone Layer: 1991 Assessment: Report of the Technology and Economic Assessment Panel. Nairobi: United Nations Environment Programme.
Substances controlled under the Montreal Protocol are used in a number of applications, including refrigeration and air conditioning, rigid and flexible foam, solvent cleaning, aerosol products, sterilisation, and a number of other miscellaneous uses.
Estimates provided to the U.S. EPA by chemical companies and estimates of the Technical Options Committees show that CFC production is now 60% of the base 1986 level. The data, shown in Tables 2.1 and 2.2, are the best available at this time. Data for Eastern Europe and some developing countries are not yet accurately compiled. Each sector has calculated approximate end use CFC reductions which may not exactly match CFC producer estimates.
2.2 REFRIGERATION
2.2.1 Current Use of CFCs in Refrigeration
Chlorofluorocarbons are used worldwide in many refrigeration applications. The commonly used CFC refrigerants are CFC-11, CFC-12, CFC-13, CFC-114, and CFC-115.
In 1991, 260,000 tonnes of CFCs were used in refrigeration, air conditioning, and heat pumps worldwide. Forty percent of this was used in refrigeration. Slightly more than 10,000 tonnes have been recovered from equipment upon service and disposal in 1991.
2.2.2 Principal Substitutes and Alternatives for CFC Use in Refrigeration, Air Conditioning, and Heat Pumps
Several options exist to reduce and eliminate CFCs in new refrigeration, air conditioning, and heat pump equipment. The options can be grouped according to the different sectors and to the expected time frame of their use. Table 2.3 presents the main alternatives in this sector.
2.2.3 Anticipated Phaseout Timetable for Refrigeration, air Conditioning, and Heat Pumps
Several CFC alternatives are being evaluated for refrigeration, air conditioning, and heat pumps. Key factors which will influence the timing and the rate of CFC replacement include:
The phaseout dates shown in Table 2.4 are anticipated for the developed countries, if HFCs and HCFCs are commercially available in sufficient quantities.
2.2.4 Implications of an Accelerated Phaseout
An earlier phaseout than 2000 will cause problems for the servicing of existing equipment, but aggressive recycling programs and retrofit can minimise the cost of obsolescence of equipment. A 1997 phaseout is estimated to cost about an additional US$ 6.2 billion (of which US$2.8 billion is attributed to automotive air conditioning) compared to a 2000 phaseout. Earlier phaseouts than 1997 would cost disproportionately more.
2.3 FOAMS
2.3.1 Production and Use of CFCs in Foam
CFC-11, CFC-12, CFC-113, and CFC-114 are all used to some extent in the manufacture of the four main types of foam:
These foams are used in a variety of foam plastic products. Building and appliance insulation represents 88 percent of CFCs in foams. Other products include cushioning materials, packaging, and microcellular foams.
The foam industry used approximately 267,400 metric tonnes of CFCs worldwide in 1986 to produce these four types of foam. Global CFC consumption in all foam sectors declined by 35 percent between 1986 and 1990, to 174,150 metric tonnes.
2.3.2 Principal Substitutes for CFC Use in Foam
Table 2.6 summarises the alternatives available and currently under research by the foam industry.
2.3.3 Anticipated CFC Phaseout Timetable and Implications for an Earlier Phaseout
The use of HCFCs in foam plastics presents the quickest path to elimination of CFCs, in developed countries in 1995, while some developing countries may require additional time to achieve CFC reductions. The applications that will rely most on HCFCs include polyurethane, phenolic and extruded polystyrene insulation products, and certain polyolefin packaging and polyurethane integral skin for automotive product applications. It is estimated that approximately 150,000 tonnes of HCFCs per year would be required to achieve a CFC phaseout in foam plastics in developed countries in 1995 .
There are considerable uncertainties affecting the timing and the rate of CFC replacement. These include: toxicity, flammability, environmental acceptability, and product energy efficiency.
Based on current technology, many foam manufacturers have few options other than HCFCs. Foam insulation products without CFC or HCFC would have poorer physical properties, poorer fire performance properties, higher cost, and poorer insulating value compared to those made with CFCs.
Table 2.5 presents the projected phaseout dates for CFC use in the foam sector.
2.4 SOLVENTS
2.4.1 Production and Use of CFCs in Solvent Applications
CFC-113 is used in electronics, metal, precision and dry cleaning, and for aerosol solvent products. The level of usage and the amounts of CFC-113 used vary with each application. In 1990, the worldwide consumption of CFC-113 was approximately 178,000 metric tonnes.
2.4.2 Production and Use of 1,1,1-Trichloroethane
1,1,1-trichloroethane is widely used in solvent, coatings, and adhesive applications. In 1988, the consumption of 1,1,1-trichloroethane in the U.S., Western Europe, and Japan was approximately 582,000 metric tonnes. The solvent uses of 1,1,1-trichloroethane are metal, precision and dry cleaning.
2.4.3 Principal Substitutes and alternatives for CFC-113 and 1,1,1-Trichloroethane
The substitutes and alternative processes which can be used to eliminate the use of CFC-113 and 1,1,1-trichloroethane in solvent applications are presented in Table 2.7.
2.4.4 Anticipated Phaseout Schedule and Implications for CFC-113 and 1,1,1-Trichloroethane Use in Solvents
The consensus findings of the UNEP Solvents, Coatings, and Adhesives Technical Options Committee on the technical feasibility of phasing out the use of CFC-113 and 1,1,1-trichloroethane are presented in Table 2.8.
All dates imply phaseout by December 31 of the year stated. The range of technically feasible phaseout dates reflect uncertainties in the commercial availability of some alternatives and substitutes and differences in the expert judgements of committee members. Accelerated phaseouts will require the development of some new technologies.
Early phaseout of 1,1,1-trichloroethane will depend on the very rapid dissemination and adoption of technologies for the replacement among many thousands of small users.
2. 5 AEROSOL PRODUCTS
2.5.1 Production and Use
CFCs have been used extensively as a propellant in aerosol products; CFCs and 1,1,1-trichloroethane have also been used as a solvent and as the active ingredient. In the mid-1970s the use of CFC-11 and -12 in aerosols accounted for about 60 percent of the total use of these chemicals worldwide. Due to mandatory and voluntary reduction programmes in various countries, this use has been substantially reduced. However, use in aerosol products is still substantial, accounting for some 115,000 metric tonnes, a reduction of some 58 percent from 1986 (approximately 20 percent of current use of controlled CFCs).
In countries which have implemented phaseout programmes, the remaining aerosol uses are principally in the industrial and pharmaceutical sectors.
2.5.2 Alternatives and Substitutes
There is a wide variety of alternatives and substitutes available for CFCs and 1,1,1-trichloroethane in aerosol products. The optimal choice will vary with the product under consideration. Each alternative has its own unique set of properties such as solvency, performance characteristics and costs.
The majority of aerosol producers have or are likely to turn to hydrocarbons. This requires reformulation, retrofitting and sometimes plant relocation (because of the increased explosion and fire risk associated with the use of these chemicals). In most countries the conversion to non-CFC propellant products is well underway. The most difficult challenge is to eliminate CFC propellants from oral inhalant drug products. Powder administration methods have been commercialized for some drugs, however, for many patients, powder inhalers are not a satisfactory alternative to the pressurized inhaler. The amount of CFCs currently used in oral inhalant drug products worldwide is 5,000-6,000 metric tonnes per year.
It is also considered difficult to eliminate CFCs from certain aerosol products used in specialized industrial or technical applications. Substitution with hydrocarbons, dimethyl ether, compressed gases, HCFCs or HFCs should be possible; however, flammability risks must be fully considered.
Table 2.9 presents various alternatives for the aerosols sector.
2.5.3 Anticipated Phaseout Time Frame
A reduction to some 15,000 tonnes of CFCs used in aerosol products worldwide should be technically possible by 1995.
Table 2.10 summarizes the technically feasible phaseout dates for specific aerosol products.
2.5.4 Implications of an Accelerated Phaseout
With the exception of oral inhalant drug products and certain small uses in developing countries, acceleration of the CFC phaseout from the year 2000 to 1997 would have a negligible impact providing transitional substances are available.
In the majority of developing countries, there is an economic incentive to use hydrocarbon propellants rather than CFCs. Lack of economic resources, land and trained personnel may constitute the main local obstacles for replacement of CFCs.
The grace period for Article 5 countries should ensure that new propellants will be introduced where flammability currently limits the use of hydrocarbons as propellants.
2.6 STERILANTS
2.6.1 Production and Use
A mixture of CFC-12 and ethylene oxide (EO) (88 percent CFC-12 and 12 percent EO) termed 12/88 is widely used by medical device manufacturers, contract services, and hospitals for gas sterilisation of medical equipment and devices.
Using CFC-12 reduces the flammability and explosion risks of EO. The total use of CFC-12 worldwide for sterilisation is estimated to be approximately 18-20,000 tonnes.
2.6.2 Alternatives and Substitutes
Table 2.11 presents currently available and emerging alternatives for replacing CFC-12 use in sterilants.
2.6.3 Anticipated Phaseout Time Frame
The use of CFC for sterilisation in developed countries can be phased out during the first half of the 1990s and not later than the end of 1995. In developing countries the substitution will probably be slower unless special efforts are made.
