China is one of the major producers of chlorodifluoromethane (HCFC-22) in the world. A large amount of fluoroform (HFC-23) is emitted during the production of HCFC-22. Emission factors of HFC-23 were calculated in accordance with the monitoring reports of eleven HFC-23 clean development mechanism (CDM) projects in China and the HFC-23 emissions in 2000–2010 as well as that in 2011–2020 were estimated and projected, respectively. It is expected that, by the end of 2020, emissions of HFC-23 in China will be as much as 230 Mt CO2 -eq. If HCFC-22 producers voluntarily reduced HFC-23 emissions, it would contribute 3.2%–3.6% to the national CO2 emission reduction target for 2020.
greenhouse gas ; HFC-23 ; potential for emission reduction
The fluoroform (HFC-23) is a by-product in production of chlorodifluoromethane (HCFC-22). The HCFC-22 is the substitution for refrigerating fluid in air conditioners of chlorofluorocarbon (CFCs) and for basic raw chemical material in the fluorine industry. China is one of the major producers of chlorodifluoromethane (HCFC-22) in the world and with its potentially high emissions of HFC-23, poses a great threat to the environment. Meanwhile the ozone depletion potential (ODP) of HFC-23 is zero. It is not a controlled matter according to Montreal Protocol on Substances that Deplete the Ozone Layer. Therefore, there is no restriction on emissions of HFC-23 in China.
The hydrofluorocarbons (HFCs) [ UN , 1998 ] is one of the greenhouse gases out of 6 categories causing global warming as listed in the Kyoto Protocol. HFC-23 is one of HFC gases. Its global warming potential (GWP) is 11,700 [ IPCC , 2007 ]. In order to push forward emission reduction of greenhouse gases, China has, since the Kyoto Protocol became effective, been actively developing and successfully registering 11 HFC-23 emission reduction clean development mechanism (CDM) Projects, with an annual registered reduction amounting to 65.65 Mt CO2 -eq. However, the future emissions of HFC-23 in China may increase due to the issue of an European Union (EU) ban① in 2011, amendment [ UNFCCC , 2010 ] of new methodology and ascending trend of HCFC-22 production in China prior to 2020. Therefore, it is of great significance to the control of emissions in China’s fluorine industry that an effort is made to analyze and study the emission trend and emission reduction potential of HFC-23.
In order to accurately calculate emissions, it is of key importance to determine the emission factor (W) of HFC-23 in the HCFC-22 production industry. Prior to implementation of the CDM projects for emission reduction of HFC-23, the HCFC-22 production enterprises directly emitted HFC-23 as waste gas into the atmosphere without specialized monitoring. In the incineration and decomposition of HFC-23 waste gas, using approved baseline methodology AM0001 [ UNFCCC , 2003 ], the W is 1.5%–3.0%. However, according to the registration and design documents of 11 HFC-23 emission reduction CDM projects, 10 enterprises were read to have a W between 2.37% and 5.44% from 2002 to 2004 using fluorine balance calculation and carbon balance calculation. Jiangsu Haike is a Sino-French joint venture. Its W is low, between 1.64% and 1.87%, due to the adoption of new French technology. During the execution of the CDM projects, the W of 10 enterprises during monitoring periods was between 2.31% and 3.64% while the W of the Jiangsu Haike project was between 1.11% and 2.26%. This paper is based on the actual monitored W during execution of 11 HFC-23 emission reduction CDM projects and on yield of HCFC-22. Its aim is to calculate W of HFC-23 in China’s HCFC-22 industry using a weighted average calculation method. The formula is shown below:
where wi ,j is generation rate (%) of HFC-23 of item i during monitoring period j, and Qi ,j is yield of HCFC-22 of item i during monitoring period j.
Waste generation rates during monitoring periods for 11 HFC-23 emission reduction CDM projects in China are shown in Figure 1 .
Waste generation rate W of the 11 HFC-23 projects in China in each monitoring period
After weighted average calculation using the yield of HCFC-22 from the 11 projects and actual yield of HFC-23, the W is 2.85%.
Since 2000, China has been undergoing rapid economic development, especially in its refrigeration and foam industries. This has brought about a rapid increase [ Yang et al., 2010 and Xu et al., 2006 ] in market demand for HCFC-22, and a continuous increase of production capacity and yield. According to statistics from China Association of Fluorine and Silicone Industry, the production data of HCFC-22 in China since 2000 is as shown in Table 1 .
Note: The data of 2010 is obtained through the use of extrapolation method
In this paper, weighted average (2.85%) of W and GWP of HFC-23 are used to estimate emissions of HFC-23 in China from 2000 to 2010 without the implementation of CDM projects. The emissions are shown in Table 2 .
If China had not implemented the HFC-23 emission reduction CDM projects, the accumulated emissions of HFC-23 from 2000 to 2010 would have been 1,110 Mt CO2 -eq. In fact, since the implementation of CDM projects for emission reduction of HFC-23 in 2006 in China, the actual incineration of HFC-23 in these projects was about 30,600 t equivalent to 358 Mt CO2 -eq by May 31, 2012. The Certified Emission Reductions (CERs) of 299 Mt CO2 -eq [ UNFCCC , 2012 ], issued by the United Nations (UN), had been obtained.
As shown in Figure 2 , the yield of HCFC-22 in 2010 increased by 236,000 t as compared with that of 2005. However, the emissions of HFC-23 in 2010 were slightly lowered as compared with those of 2005 due to the implementation of CDM projects in China since 2006. About 6,907 t HFC-23 had been incinerated. The incinerated HFC-23 offset the emissions due to an increase in yield of HCFC-22.
HFC-23 emissions in China from 2000 to 2010
The emissions of HFC-23 in China in the future will be affected by many factors such as international conventions, the carbon market, domestic greenhouse gas reduction policies and industrial policies. Various restrictions and influences should be taken into consideration for the estimation and prediction of China’s emission trend of HFC-23.
The EU prohibited the emission reduction of CDM projects using industrial exhaust gas to deduct the emission reduction obligation of EU enterprises and trading of EU Emission Trading System (EUETS) from May 1, 2013. Major buyers of China’s HFC-23 emission reduction CDM projects are EU enterprises and the World Bank. Currently, there are 8 projects facing expiration of purchase agreement or termination of purchase agreement by buyers, though with the exception of the Changshu San’aifu Project, Jiangsu Meilan Project and first season of Juhua Stage-I Project which were bought by the World Bank have expired. The issuance of the EU ban stopped the trading of 90% emission reductions of 11 HFC-23 emission reduction CDM projects in China. Loss of economic incentives caused direct emissions of the gases.
In November, 2011, the 65th session of Executive Board of UN Clean Development Mechanism passed a new methodology [ UNFCCC , 2010 ] for HFC-23 emission reduction CDM projects. The amendment of the methodology not only lowered the W to 1/3 of its original value, but also reduced the maximum value of yield of qualified HCFC-22 in three successive years from 2000 to 2004 to the average value. Currently, the annual emission reduction of the 11 HFC-23 emission reduction CDM projects in China is 80.81 Mt CO2 -eq, of which 65.91 Mt CO2 -eq is qualified emission reduction and may apply for trading, and the emission reduction of the remaining 14.9 Mt CO2 -eq are obtained through voluntary incineration by enterprises. The projects will finish first-season operation in 2013 and 2014 successively. New methodology is required if enterprises apply for second-season operation. According to requirements of the new methodology, the qualified emission reductions of the 11 projects in China will be lowered to 23.41 Mt CO2 -eq, in other words, lowered by 65% as compared with the first-season operation. Though the W is lowered, the actual generation rate of HFC-23 is difficult to lower. Therefore, enterprises will incinerate HFC-23 of 80.81 Mt CO2 -eq, which significantly lowers profit for the country and enterprises.
In December, 2011, the National Development and Reform Commission issued Notice on Carrying out Carbon Emission Trading Pilot Program (hereinafter referred to as Notice). The Notice introduced the requirements on the domestic carbon emission trading market to be implemented in the twelfth Five-Year Plan. Carbon emission trading pilot③ will be carried out in seven provinces and cities such as Beijing, Tianjjin and Shanghai. In July, 2012, the National Development and Reform Commission issued Temporary Method for Management of Voluntary Emission Reduction Trading of Greenhouse Gases, which stated that the greenhouse gases of 6 categories under the Kyoto Protocol may be used involuntary emission reduction trading④ of domestic greenhouse gases. Up to now, Guangzhou Carbon Emission Exchange has finished the first order of carbon trading. Four enterprises in Guangdong spent 67.99 million RMB to subscribe emission quota of 1.3 Mt CO2 , becoming the first quota trading⑤ based on control of carbon emissions in China. Under the condition that the emission reduction of HFC-23 CDM project loses the international market, the establishment of a domestic carbon trading market will open up a new path for China to use market mechanism to reduce emissions of HFC-23.
In December, 2008, the Ministry of Environmental Protection issued Notice on Strict Control of New Projects, Transformation Projects and Extension Projects for Production of HCFC, which states that the new projects, transformation projects and extension projects for production of HCFC must be approved by the Ministry of Environmental Protection [ MEP , 2008 ]. In 2010, the production capacity of HCFC-22 in China was 700,000 t [ CAFSI , 2011 ]. With elimination progress of HCFC-22 production and application according to the Montreal Protocol on Sub-stances that Deplete the Ozone Layer, China will not approve new projects, transformation projects and extension projects of HCFC-22 by 2020. This may stabilize the production capacity of HCFC-22 at the 2010 level, thus controlling emissions of HFC-23. The estimated yield of HCFC-22 in China by 2020 is shown in Table 3 . The yield will increase to 700,000 t in 2020. The yield of HCFC-22 from 2010 to 2020 shows an increasing trend.
The baseline scenario and emission reduction scenario are designed according to analysis of change in international and domestic policies and the carbon market, estimated yield of HCFC-22 and implementation of HFC-23 emission reduction CDM projects in China. Non-adoption of measures by China’s HCFC-22 production enterprises after 2013 is used as a baseline scenario. The emissions of HFC-23 in China by 2020 will reach 230 Mt CO2 -eq, increasing by 130% than that of 2010. Four emission reduction scenarios are designed. Scenario 1: the HFC-23 emission reduction CDM projects have finished the first-season operation, and then enterprises stop incineration of HFC-23 due to lack of economic incentives. Scenario 2: domestic carbon trading begins in 2013 and 11 existing HFC-23 emission reduction CDM projects continue to incinerate HFC-23 with trading of emission reduction carried out domestically. Scenario 3: domestic carbon trading began in 2013. Trading of emission reduction for 11 existing HFC-23 emission reduction CDM projects is carried out domestically; after 2015, the enterprises without HFC-23 emission reduction CDM projects will establish HFC-23 incineration facilities due to economic incentives. All HFC-23 emitted by China’s HCFC-22 production enterprises are incinerated. Scenario 4: the profit brought about by the domestic carbon market is not sufficient to encourage enterprises to incinerate HFC-23, and the state invests funds to introduce advanced technology and reduce value W of HFC-23 to 2.0%. The estimated emissions of HFC-23 based on the baseline scenario and emission reduction scenarios from 2011 to 2020 is shown in Figure 3 .
Prediction of HFC-23 emissions in China from 2011 to 2020
According to analysis of above scenarios, the yield of HCFC-22 in 2020 will be 700,000 t with yield of HFC-23 about 20,000 t. If the 11 HFC-23 emission reduction CDM projects are continued, 7,000 t HFC-23 may be incinerated with actual emissions of 13,000 t approximating to 150 Mt CO2 -eq. If HCFC-22 production enterprises can achieve voluntary emissions reduction, the maximum emission reduction potential in China’s fluorine industry in 2020 will reach 230 Mt CO2 -eq. The routine meeting of the State Council held on November 25, 2009 made the decision that the carbon emissions of per unit GDP in China in 2020 will decrease by 40%–45% as compared with that of 2005. This index is incorporated into long-and-medium planning of national economic development and social development. According to the requirements, the emissions of CO2 per GDP (10,000 RMB) in China will be lowered to 1.64–1.51 t CO2 . The prediction is made according to an increase rate of GDP of 7% during the Twelfth Five-Year Plan and an increase rate of GDP of 6% during the Thirteenth Five-Year Plan. Emission reduction will be 6.46–7.27 Gt CO2 in 2020 based on that of 2005. If calculated according to the scenario of maximum emission reduction of HFC-23, it will equal to 3.2%–3.6% of national emission reduction target in 2020.
As a result of international policies, the trading of HFC-23 emission reduction CDM projects has been obstructed and the qualified emission reductions drop sharply. From 2013 enterprises face the problem of choosing whether the emission reduction should be continued. However, according to above analysis, there is great potential for emission reduction of the by-product HFC-23 during production of HCFC-22. The maximum emission reduction potential may reach 230 Mt CO2 -eq. The incineration of HFC-23 is of great significance to emission reduction of greenhouse gases in China. Thus it is proposed that the following measures should be taken:
(1) As for enterprises that can not carry out trading in the first-season operation due to EU ban, the CDM funds will be used to support the incineration of HFC-23 until completion of first-season operation. The implementation of the policy will reduce emissions of 110 Mt CO2 -eq.
(2) Encourage enterprises to continue incineration of HFC-23. Firstly, continue to use CDM funds under the Kyoto Protocol to reduce emissions of HFC-23.
The state will cancel the minimum price-limitation requirements on certified emission reductions for HFC-23 emission reduction CDM projects. The tax preferential policies of 3-Year Free and 3-Year Half will be provided to the enterprises with HFC-23 emission reduction projects. Reference to other CDM projects will be made to lower the profit proportion to 2% paid by enterprises to CDM funds. Secondly, use the incinerated amount to offset energy consumption of enterprise.
(3) Carry out domestic carbon trading as soon as possible, so as to realize domestic trading of emission reductions of HFC-23 projects which cannot be carried out in international trading, thus reducing total cost of carbon emission reduction.
(4) Use CDM funds to purchase emission reductions of HFC-23 projects which cannot be carried out through international trading, so as to complete emission reduction goal of industries with higher cost in emission reduction.
(5) Use CDM funds to support HCFC-22 production enterprises in carrying out technical transformation to reduce the generation rate of HFC-23 to about 2%, thus reducing emissions of HFC-23 by 1/3. If the technical transformation can be completed during the Twelfth Five-Year Plan, the emission reduction of 330 Mt CO2 -eq during the Thirteenth Five-Year Plan may be achieved.
(6) Actively carry out international cooperation to seek various methods to reduce emissions of HFC-23 which does not conform to CDM project requirements.
This work is supported by Special Fund for Public Environmental Research “Study of the Characterization of Non-CO2 Green House Gases Emissions and the Framework for Policy Control” (No. 201009052).
②. The data is sourced from website of UNFCCC: http://cdm.unfccc.int/filestorage/Y/K/R/YKRDQPIGXZ7J12A46HUS9BTCF53NOM/HCFC-22%20Production%20Data%20and%20Market%20in%20China.pdf?t=d3p8bTdwZGI3fDBYkxFh1ao7-OepkO7oJ_AZ