Pollution Prevention and Abatement Handbook WORLD BANK GROUP Effective July 1998 Ozone-Depleting Substances: Alternatives Surrounding the earth at a height of about 25 international environmental agreement, and its kilometers is the stratosphere, rich in ozone, signing by so many nations represented a major which prevents the sun’s harmful ultraviolet accomplishment, and a major shift in the ap- (UV-B) rays from reaching the earth. UV-B rays proach to handling global environmental prob- have an adverse effect on all living organisms, lems. The Protocol called for a freeze on the including marine life, crops, animals and birds, production of halons and a requirement to reduce and humans. In humans, UV-B is known to af- the production of CFCs by 50% by 1999. How- fect the immune system; to cause skin cancer, eye ever, new scientific evidence surfaced after the damage, and cataracts; and to increase suscepti- entry into force of the Protocol, indicating that bility to infectious diseases such as malaria. ozone depletion was more serious than originally In 1974, it was hypothesized that chlorinated thought. Accordingly, in 1990 (London), 1992 compounds were able to persist in the atmo- (Copenhagen), and 1995 (Vienna), amendments sphere long enough to reach the stratosphere, were made to the Protocol to regulate the phase- where solar radiation would break up the mol- out of the original chemicals and the control and ecules and release chlorine atoms that would phase-out of additional chemicals. destroy the ozone. Mounting evidence and the discovery of the Antarctic ozone hole in 1985 led to the global program to control chlorofluorocar- Table 1. Ozone Depletion Potential (ODP) of the bons (CFCs) and other ozone-destroying chemi- Principal Ozone-Depleting Substances (ODSs) cals. In addition to Antarctica, ozone loss is now ODS ODP present over New Zealand, Australia, southern Argentina and Chile, North America, Europe, CFC-11 1.0 and Russia. CFC-12 1.0 The ozone-depleting chemicals or substances CFC-113 0.8 CFC-114 1.0 (ODSs) of concern are CFCs, halons, methyl chlo- CFC-115 0.6 roform (1,1,1,-trichloroethane; MCF), carbon tet- CFC-111, -112, -13, -211, -212, rachloride (CTC), hydrochlorofluorocarbons -213, -214, -215, -216, -217 1.0 (HCFCs), and methyl bromide. The ozone deple- Halon 1211 3.0 tion potential (ODP) for these chemicals is shown Halon 1301 10.0 in Table 1. CFC-11 was assigned an ODP of 1.0; Halon 2402 6.0 all other chemicals have an ODP relative to that Carbon tetrachloride (CTC) 1.1 Methyl chloroform (MCF); of CFC-11. An ODP higher than 1.0 means that 1,1,1-trichloroethane 0.1 the chemical has a greater ability than CFC-11 to HCFC-22 0.05 destroy the ozone layer; an ODP lower than 1.0 HCFC-123 0.02 means that the chemical’s ability to destroy the HCFC-124 0.02 ozone layer is less than that of CFC-11. HCFC-141b 0.15 In September 1987, the Montreal Protocol on HCFC-142b 0.06 Substances That Deplete the Ozone Layer (the HCFC-225ca 0.01 HCFC-225cb 0.04 Protocol) was signed by 25 nations and the Eu- Methyl bromide 0.7 ropean Community. The Protocol was the first 250 Ozone-Depleting Substances: Alternatives 251 The principal provisions of the Montreal Pro- preinvestment studies, training and work- tocol as it now stands are as follows: shops, demonstration projects, investment project design, and country programs. • Production of CFCs, halons, methyl chloro- • The United Nations Industrial Development Or- form, and CTC ceased at the end of 1995 in ganization (UNIDO) implements small and me- industrial countries and will cease by 2010 in dium-scale projects, feasibility studies at the developing countries. Developing countries plant level, technical assistance and training, are defined in the Protocol as those that use and country programs. less than 0.3 kilograms (kg) of ODS per capita per year. They are often called Article 5 coun- Uses of ODSs tries in reference to the defining article in the Montreal Protocol. In general, ODSs are most often used in the fol- • HCFCs, originally developed as a less harm- lowing applications: ful class of CFC alternatives, will be phased out by 2020 in industrial countries, with some • As propellants in aerosols (CFCs and HCFCs) provisions for servicing equipment to 2030. • In refrigeration, air conditioning, chillers, and Developing countries are to freeze consump- other cooling equipment (CFCs and HCFCs) tion by 2016 (base year 2015) and phase out • To extinguish fires (halons) use by 2040. • In the manufacture of foams (CFCs and • Consumption and production of methyl bro- HCFCs) mide will end in 2005 in industrial countries • As solvents for cleaning printed circuit boards (subject to phase-out stages and exemptions) and precision parts and degreasing metal parts and in 2015 in developing countries. (CFCs, HCFCs, methyl chloroform, and CTC) • In a variety of other areas, such as inks and It was early recognized that undue hardships coatings and medical applications (CFCs, might be experienced by industry in developing HCFCs, methyl chloroform, and CTC) countries as they implemented replacement tech- • As a fumigant (methyl bromide). nologies. Therefore, a fund was established un- der the Montreal Protocol to pay for incremental Alternative Technologies, Processes, costs such as technical expertise and new technolo- and Chemicals gies, processes, and equipment associated with the phase-out. The Multilateral Fund of the Montreal Protocol is managed by an executive committee The following discussion provides a brief over- consisting of delegates from seven developing view of the alternatives to ODSs that have been countries and seven industrial countries. The fol- developed in various sectors. It is not intended lowing international organizations have been to be an exhaustive listing of all alternatives, but made Implementing Agencies of the Multilateral it does summarize some proven alternatives and Fund for the purpose of helping governments give an indication of future development trends. and industries in developing countries with their The selection of any alternative should be made programs to eliminate ODSs. (The roles outlined with due consideration of other issues that could here are not intended to be exhaustive.) affect the final choice. Identification, development, and commercial- • The World Bank assists developing coun- ization of alternatives to ODSs are going on con- tries with investment projects, country stantly. For this reason it is important to seek programs, workshops, training, and institu- information on the latest alternatives from the tional strengthening. World Bank’s Global Environment Coordination • The United Nations Environment Programme Division. Technological updates are provided by (UNEP) has a clearinghouse function that in- the World Bank’s Ozone Operations Resource cludes information exchange, country pro- Group, which is made up of experts in halons, grams, training, and workshops. solvents, aerosols, refrigerants, mobile air con- • The United Nations Development Programme ditioning, foam blowing, and chemical produc- (UNDP) is responsible for feasibility and tion. For any alternative, consideration needs to 252 PROJECT GUIDELINES: POLLUTANT CONTROL TECHNOLOGIES be given to, for example, its compatibility with Rigid polyurethane for other appliances. Alterna- existing equipment, its health and safety aspects, tives include HCFC-141b, HCFC-22, blends of its direct global-warming potential, whether it in- -22 and HCFC-142b, pentane, and carbon diox- creases or decreases energy consumption, and the ide/water blowing. In the long term, the alter- costs that may be incurred in eventual conversion natives include HFCs. to a non-ODS technology if an interim HCFC al- ternative is chosen. New ways of doing business Rigid polyurethane used for boardstock and flex- may also develop in the course of review and se- ible-faced laminations. Alternatives include HCFC- lection of alternatives. For example, many elec- 141b and pentane; in the long term, the use of tronics companies have now converted their HFCs should be developed. manufacturing plants to “no-clean” technology. The benefits include elimination of circuit board Sandwich panels of rigid polyurethane. HCFC- cleaning after soldering, savings in chemical costs 141b, HCFC-22, blends of HCFC-22 and -141b, and waste disposal costs, savings in maintenance pentane, and HFC-134a are now used as alterna- and energy consumption, improved product qual- tives to CFCs in this application. In the long term, ity, and advances toward new technologies such HFCs and carbon dioxide/water will be the re- as fluxless soldering. The selection of any alterna- placement technologies. tive should not be made in isolation from the fac- tors listed above. Spray applications of rigid polyurethane. Alterna- tives currently in use for spray applications in- Flexible and Rigid Foams clude carbon dioxide/water and HCFC-141b. Long-term alternatives will be HFCs. Zero-ODP alternatives are the substitutes of choice in many foam-manufacturing applica- Slabstock of rigid polyurethane. Alternatives in- tions. However, the use of HCFCs is sometimes clude HCFC-141b; long-term alternatives include necessary in order to meet some product specifi- HFCs and carbon dioxide/water. Pentane may cations. The viability of liquid hydrofluorocarbon also be used. (HFC) isomers in this industry remains to be proved, and hydrocarbon alternatives need to be Rigid polyurethane pipe construction. CFCs in this better qualified, as well. The issues in these evalu- application are being replaced by carbon dioxide/ ations are safety (toxicity and flammability), en- water, HCFC-22, blends of HCFC-22 and -142b, vironmental impact (generation of volatile HCFC-141b, and pentanes. Long-term alternatives organic compounds and global warming), prod- will include HFCs and carbon dioxide/water. For uct performance (insulating properties, confor- district central heating pipes, pentane and carbon mity to fire codes, and the like), cost and dioxide/water are the preferred technologies. availability, and regulatory requirements.