N 2 O emissions from nitric acid plants in CDM and JI projects

Transcription

1 N 2 O emissions from nitric acid plants in CDM and JI projects S. Debor, V. Schmidt and Dr M. von Velsen-Zerweck of N.serve Environmental Services GmbH present a summary of a first-of-a-kind comprehensive analysis of N 2 O baseline emissions and reduction results that have been achieved in nitric acid plants that are taking part in the Clean Development Mechanism (CDM) and Joint Implementation (JI) of the Kyoto Protocol. Before the existence of the Kyoto Protocol there was no worldwide regulation and monitoring of N 2 O emissions from the nitric acid industry. All discussions to date with regard to the regulation of the greenhouse gas N 2 O and appropriate benchmarks have been based on sample measurements, estimates and assumptions rather than data from continuous third party audited monitoring procedures. The success of the nitric acid projects under the CDM and JI mechanisms of the United Nations Framework Convention on Climate Change (UNFCCC) changed this situation profoundly. To date, the market incentives provided by the Kyoto emissions markets has led to 58 registered CDM projects in nitric acid plants that benefit from emissions trading. As a result, innovative and expensive state-of-the-art environmental technology to reduce and to monitor N 2 O emissions has been introduced to developing countries years ahead of the technology being used in western industrialised countries. This article summarises a broad analysis that has been conducted by N.serve Environmental Services GmbH, a leading company in the development of N 2 O emission reductions projects in nitric acid plants with 34 plants under contract to date. N 2 O emission monitoring data from CDM projects registered under the UNFCCC are presented. The data are a) third party audited, b) publicly available 1 and c) derived from state-of-the-art monitoring systems & standards. In addition, first N 2 O emission reduction data from JI projects are presented, most of which have just started to reduce emissions. The results from these first emission reduction projects are of high relevance for the policy processes that are currently taking place for the nitric acid plants covered under the European Emission Trading System (EU ETS) for the third trading period ( ). The results will also likely affect regulation in the USA, where regulation for the nitric acid industry and its integration into emission trading systems through benchmarking is being discussed on both a state and national level. The analysis enables the industry and policy makers to balance out the different environmental, technical and economical interests. Technically and financially feasible N 2 O benchmarks can be defined for specific plant categories that at the same time guarantee an effective reduction of greenhouse gas emissions, while incentivising the nitric acid industry to consistently achieve these levels. N 2 O emission reductions in CDM projects The average expectation of N 2 O reductions in CDM projects in nitric acid plants was significantly higher before the first projects were implemented. According to the published Project Design Documents (PDDs) 2 these estimates ranged between l 80% - 90% when implementing secondary abatement technology and l 85% - 95% when implementing tertiary abatement technology. However, based on N 2 O emission data obtained from the monitoring reports the N 2 O emission reductions achieved in existing CDM projects fall significantly short of these expectations (see Table 1): 36% of the presented CDM plants that installed secondary catalyst technology under the United Nations Framework Table 1: Average emission factors and abatement efficiency achieved in operating CDM projects Item AM0028 CDM AM0034 CDM Overall (tertiary catalyst) (secondary catalyst) Average baseline emission factor, kgn Average project emission factor, kgn Average abatement efficiency, % Nitrogen+Syngas 307 September - October

2 Fig 1: CDM reduction projects in nitric acid plants using secondary and tertiary N 2 O abatement technology Baseline emission factor [kgn 2 ] Project emission factor [kgn 2 ] Reduction efficiency [%] 97.7% 99.2% 97.2% 98.1% 97.7% 97.0% 94.9% 94.5% 94.5% 92.7% 87.4% 88.9% 87.5% 85.9% 86.2% 87.0% 77.0% 87.3% 82.8% 83.0% 88.0% 84.3% 78.0% 71.2% 71.7% 64.9% 75.3% 76.2% 67.3% 68.1% 71.1% 69.8% 75.2% 62.6% 56.7% 50.0% 57.7% 54.8% 60.5% 49.8% 55.3% 45.7% 49.6% 34.0% 34.5% 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% AVE AVE AVE ALL 2 Nitrogen+Syngas 307 September - October 2010

3 Table 2: Overview emission factors in AM0034 projects (secondary technology) Plant type Baseline emission factor Project emission factor Reduction efficiency (kgn 2 ) (kgn 2 ) (%) Low pressure Medium pressure High pressure Table 3: Overview emission factors in AM0028 projects (tertiary technology) Plant type Historic emission factor Project emission factor Reduction efficiency (kgn 2 ) (kgn 2 ) (%) Low pressure Medium pressure High pressure Table 4: Existing CDM N 2 O nitric acid reduction projects Overview of CDM N 2 O reduction projects Number of projects Number of plants Third party validated and registered CDM N 2 O reduction under UNFCCC AM0034 CDM AM0028 CDM 8 14 CDM N 2 O reduction for which monitoring reports are publicly available AM0034 CDM AM0028 CDM 8 14 Convention on Climate Change (UNFCCC) approved methodology (AM) AM0034 were actually able to achieve a reduction of N 2 O emissions within the expected range of 80-90%. 71% of the presented CDM plants that installed tertiary technology under the UNFCCC methodology AM0028 were able to achieve a reduction of N 2 O emissions within the expected range of 85-95%. The reduction levels achieved show that N 2 O reduction technology is not yet in a state of development where consistent results are delivered due to the early stages of technology and technical differences between plants. The graph in Fig. 1 provides an overview of the current emission factors and abatement efficiency achieved in operating CDM projects. Historic and current CDM N 2 O emissions Tables 2 and 3 summarise the historic baseline and current emission levels of CDM N 2 O projects that installed secondary technology (under AM0034) or tertiary technology (under AM0028). CDM N 2 O emission reduction database The N 2 O emission data provided are third party audited concluding a) N 2 O baseline emissions from nitric acid plants and b) N 2 O emission reduction levels achieved with secondary and tertiary abatement technology in these plants. The data used in the first graph are obtained from CDM N 2 O emission reduction projects in nitric acid plants realised under the UNFCCC approved methodologies ( l AM0034: Catalytic reduction of N 2 O inside the ammonia burner of nitric acid plants l AM0028: Catalytic N 2 O destruction in the tail gas of nitric acid plants Projects that installed secondary technology under the AM0034 methodology not only need to comply with the UNFCCC auditing procedure (validation, verification), but in addition need to comply with a second monitoring standard, the European Norm EN This results in an exceptional high quality and credibility of the established database. Table 4 shows the number of existing CDM N 2 O nitric acid reduction projects and plants. Emission reductions generated by JI projects As with CDM projects, the average expectations for JI N 2 O reduction projects as stated in the PDDs range from 80% to 90% for secondary technology and 85% to 95% for tertiary technology. To date, only a limited number of JI projects have completed a full campaign with installed abatement technology and it is therefore too early to draw final conclusions about emission reductions realised in JI projects. Historic & current JI N 2 O emissions Table 5 summarises the historic and current emission levels of JI N 2 O nitric acid projects that installed secondary (under AM0034) or tertiary N 2 O abatement technology (under AM0028). It is important to note that, due to the incomplete datasets of many JI projects, both in terms of length Nitrogen+Syngas 307 September - October

4 Fig 2: JI projects in nitric acid plants using secondary and tertiary N 2 O abatement technology Baseline emission factor - JI [kgn 2 ] Project emission factor - JI [kgn 2 ] Abatement efficiency - JI [%] 99.9% 96.2% 95.7% 90.3% 85.3% 94.5% 95.8% 94.7% 92.0% 92.5% 89.3% 91.9% 90.4% 90.6% 87.9% 88.3% 82.3% 83.6% 80.8% 80.2% 69.2% 69.0% 64.6% 61.5% 46.7% 52.2% 36.5% 20.0% 0.0% = monitoring report available X of Y: X= number of days for which monitoring data are available Y= average number of days of design production campaign Plants that have not run a full campaign do not provide representative data yet. Red graphs = plants with tertiary technology 79.2% 75.7% 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% 11 of 345; tertiary 6 of of of of of of of of 170 ; sec & tertiary 394 of of 360 verified average JI all average JI only & full campaign 4 Nitrogen+Syngas 307 September - October 2010

5 of monitoring periods and incomplete auditing procedures, it is not yet possible to draw the same kind of conclusions about achieved emission reductions and abatement efficiencies compared with the quality of data available for CDM N 2 O nitric acid projects. To date, only one monitoring report is available for a JI project with tertiary technology, thus averages of plants using tertiary technology under JI cannot be provided. JI N 2 O emission reduction database In contrast to CDM projects, JI project data do not yet provide the same quality of N 2 O emission data due to the two main reasons: only 11 out of 20 JI projects have produced publicly available and third party audited data to date and the majority of track-one JI projects in western European countries must apply a benchmark emission factor of between 1.85 kgn 2 and 2.5 kgn 2. Only emission reductions below the benchmark are eligible for tradable credits. Therefore, high qualitative baseline emission data do not Table 5: Average emission factors and abatement efficiency in JI projects Item Overall Average baseline emission factor, kgn Average project emission factor, kgn Average abatement efficiency, % 75.7% Table 6: Overview of existing JI N 2 O nitric acid reduction projects Overview of JI N 2 O reduction projects Number of projects Number of plants Third party validated JI N 2 O reductions AM0034 (or equivalent) JI AM0028 (or equivalent) JI 2 2 JI N 2 O reductions for which monitoring reports are publicly available AM0034 (or equivalent) JI AM0028 (or equivalent) JI 1 1 exist, since actual baseline measurements are not required. Table 6 provides an overview of existing JI N 2 O nitric acid reduction projects. The graph in Fig. 2 provides an overview of the current emission factors and abatement efficiency achieved in operating JI projects. All plants for which monitoring reports () are available are marked with in the graphs. n References Nitrogen+Syngas 307 September - October