博士学位论文
Mechanism of Low-NOx Emission in Circulating Fluidized-Bed
Decoupling Combustion
作者姓名:
指导教师:
DO HAI SAM
许光文 (研究员,中国科学院过程工程研究所)
高士秋 (研究员,中国科学院过程工程研究所)
学位类别:
工学博士
学科专业:
化学工程
培养单位:
中国科学院过程工程研究所
2018 年 6 月
Mechanism of Low-NOx Emission in Circulating Fluidized-Bed
Decoupling Combustion
A dissertation submitted to
University of Chinese Academy of Sciences
in partial fulfillment of the requirement
for the degree of
Doctor of Philosophy
in Chemical Engineering
By
Hai-Sam Do
Supervisors: Professor Guangwen Xu
Professor Shiqiu Gao
Institute of Process Engineering
Chinese Academy of Sciences
June 2018
摘 要
摘
要
循环流化床解耦燃烧(CFBDC)实现低氮氧化物(NOx)排放的技术可行性
已在处理白酒糟(DSL)的工业示范装置上得到了很好验证。低 NOx 排放被认
为是由包括焦炭,焦油和热解气(py-gas)的 DSL 热解产物在燃烧器中再燃时共
同还原 NOx 的结果。为揭示 CFBDC 系统中还原 NOx 的机理,本研究采用实验
室规模的沉降炉(DTR)反应器,模拟 CFBDC 再燃条件,研究了生物质半焦、
焦油和热解气对 NO 的还原能力,并因此概算了 CFBDC 中各热解产物组分的潜
在作用。
本论文在 500℃下热解 DSL 制备测试用半焦和焦油,py-gas 根据实验所得热
解气的组成采用钢瓶气配制。为确保 NO 被充分还原,大多数实验在反应物总质
量给料速度 0.15g / min 条件下进行。第 4 章首先研究了 NO 还原效率(ηe)随反
应物进料速率、再燃化学计量比(SR)、反应温度、停留时间和初始烟气组成的
变化。结果表明,在相同质量流速条件下,焦油较半焦和热解气更能抑制 NO 的
产生。热解气中 CO 的存在抑制了均相 NO 还原反应,导致热解气的 ηe 较低。对
于由 DSL 制备的半焦和焦油,高温和高的初始 NO、CO 浓度促进其对 NO 的还
原。
本章的主要结论是:
通过热解产物再燃烧获得最高 ηe 的适当 SR 值为 0.6-0.8。
基于上述结果,第 5 章研究了焦炭,焦油和热解气对 NO 还原的协同效应。
结果表明,NO 还原物的总质量流速一定时,焦炭/热解气混合物(二元反应物)
比其它混合物能够实现最佳的协同 NO 还原效果,且还原效率随着热解气比例的
增加而升高。而只有当焦油比例降低至 26%时,焦油/热解气或焦油/半焦混合物
才产生积极作用。此外,热解产物在还原 NO 过程中,焦炭与某些物质(如 H2,
CxHy)之间存在有效的相互作用,其协同效应与反应物中 C,H 元素与进料 NO
的摩尔比密切相关(CH/NO 比)。
第 6 章进一步研究了来源于其他燃料如木屑(SD)和先锋(XF)褐煤的焦
炭和焦油的还原能力。在一定的还原物质量比率下(0.15g/min),SD 焦炭或 XF
褐煤焦由于灰分含量较低(具有催化物质),还原 NO 效率低于 DSL 焦炭,但
SD 焦油在三种焦油中实现的 ηe 最高。值得注意的是,焦油总是表现出比焦炭更
好的 NO 还原能力。以苯酚、苯、乙酸、乙酸甲酯和庚烷等作为模型焦油化合物
I
循环流化床解耦燃烧过程低 NOx 排放机理研究
还原 NO 的实验表明, 焦油中的苯酚发挥的作用显著。无论是生物质焦油还是
煤焦油,含有至少一个芳香环(如苯酚,苯)的化合物组分都是还原 NO 的主要
贡献者。
本研究的结果将对应用 CFBDC 技术处理富 N 燃料在操作运行方面具有重
要指导意义。考虑到热解产生的焦油是降低 CFBDC 中 NOx 排放的主导因素,
建议今后研究集中于焦油还原 NO 的动力学,以及焦油与其他成分的协同作用。
另外,热解温度对不同反应物还原 NO 活性的影响也值得研究。
关键词:热解,NO 还原,再燃,解耦燃烧,循环流化床,生物质,煤,低 NOx
燃烧,下降管反应器。
II
Abstract
Abstract
The technical feasibility of low-NOx circulating fluidized-bed decoupling
combustion (CFBDC) has been well proved in an industrial demonstration plant
treating distilled spirit lees (DSL). The lowered NOx emission was believed to result
from the combined contributions of DSL pyrolysis products including char, tar, and
pyrolysis gas (py-gas) to the reduction of NOx via their reburning in the riser combustor
of the CFBDC system. In order to further understand the mechanism of NOx reduction
in CFBDC, this study is devoted to investigating the capabilities of biomass char, tar
and py-gas for NO reduction through experiments in a lab-scale drop-tube reactor (DTR)
that simulates the reburning conditions occurring in CFBDC.
The work performed pyrolysis of DSL at 500 °C to produce the tested char and tar
reactants while py-gas was prepared by mixing pure gases from cylinders according to
the analyzed py-gas composition. In order to ensure the sufficient reduction of NO, a
total mass feeding rate of reagents, which is 0.15 g/min, was adopted for most
experiments. We first investigated in Chapter 4 the variations of acquired NO reduction
efficiency (ηe) with major parameters including reagent feeding rate, reburning
stoichiometric ratio (SR), reaction temperature, residence time, and initial flue gas
composition. It was found that tar enabled the best NO reduction in comparison to char
and py-gas did at the same mass feeding rate of reagent (0.15 g/min). The presence of
CO in py-gas inhibited the homogeneous NO reduction reactions to cause lower ηe. For
DSL-derived char and tar, their realized ηe were facilitated through by higher
temperatures and higher initial NO and CO concentrations. The main conclusion of this
chapter is that the suitable SR values for obtaining the highest ηe by reburning of
pyrolysis products were found to be 0.6 − 0.8.
Based on preceding results, the synergetic effects among char, tar and py-gas
reagents on NO reduction were evaluated and discussed in Chapter 5. The comparison
at given total mass flow rate of NO-reduction reagent indicated that the char/py-gas
(binary reagent) enabled the best synergetic NO reduction than the others did. Its
realized efficiency elevated with increasing of the py-gas proportion. The tar/py-gas or
tar/char mixture caused a positive effect only when the tar proportion was necessarily
lowered to about 26%. In addition, there existed obvious interactions between char and
some species in py-gas (i.e., H2, CxHy) for NO reduction by pyrolysis products. The
III
Mechanism of Low-NOx Emission in Circulating Fluidized-Bed Decoupling Combustion
synergetic effects were closely related to the molar ratio of C and H elements in reagents
over the fed NO (CH/NO ratio).
The NO reduction capabilities of char and tar reagents derived from other fuels
such as sawdust (SD) and Xianfeng (XF) lignite were further investigated in Chapter 6.
At the specified mass flow rate of reductant, say, 0.15 g/min, the SD char or XF lignite
char were less efficient than the DSL char did for reducing NO because of the lower
contents of ash (containing catalytic matters) in the SD and XF lignite chars. However,
the SD tar enabled the highest ηe among the three tested tars. Above all, tar as an
attractive reagent always exhibits the better NO reduction than char does. Testing model
tar compounds including phenol, benzene, acetic acid, methyl acetate and heptane for
NO removal revealed that phenol plays an important role in enabling the good NO
reduction by the SD tar. Our major understanding from testing the NO reduction by tar
is that the compounds containing at least one aromatic ring (e.g. phenol, benzene) are
the major contributor for reducing NO in either biomass tar or coal tar.
In conclusion, the results of this study would be significant in the operation of
CFBDC technology treating N-rich fuel. By considering the pyrolysis-generated tar as
a dominant factor in lowering NOx emission in a CFBDC system, further studies are
suggested to focus on kinetic analysis of the NO reduction by tars and also on the
combined action of tar with other reagents. Additionally, the effect of pyrolysis
temperature on NO reduction activity by various reagents should be investigated.
Key words: pyrolysis, NO reduction, reburning, decoupling combustion, circulating
fluidized bed, biomass, coal, low-NOx combustion, drop-tube reactor.
IV
Table of Contents
Table of Contents
Chapter 1 Introduction ..........................................................................1
1.1
Background .................................................................................................... 1
1.2
Objectives and Significance ........................................................................... 3
1.3
Thesis Outline ................................................................................................ 4
Chapter 2 Literature Review .................................................................7
2.1
Nitric Oxides .................................................................................................. 7
2.1.1 Sources of NOx .......................................................................................... 7
2.1.2 NOx Emission in China ............................................................................. 7
2.2
Low-NOx Emission Strategy ......................................................................... 9
2.2.1 NOx Formation During Fuel Combustion ................................................. 9
2.2.2 NOx Reduction Technologies .................................................................. 11
2.3
Decoupling Combustion (DC) for Lowering NOx Emission ...................... 14
2.3.1 Principle of Decoupling and DC Technology .......................................... 14
2.3.2 Low-NOx Emission in Grate-Based DC.................................................. 16
2.3.3 Low-NOx Emission in CFBDC ............................................................... 18
Chapter 3 Material and Methodology ................................................25
3.1
Preparation of NO-Reduction Reagents....................................................... 25
3.1.1 Feedstock Material ................................................................................... 25
3.1.2 Pyrolysis Setup and Procedure................................................................. 25
3.1.3 Characteristics of NO-Reduction Reagents ............................................. 28
3.2
Experimental Drop-Tube Reactor for NO-Reduction Evaluation ............... 30
3.2.1 Main Chamber ......................................................................................... 30
3.2.2 Heating Control System ........................................................................... 31
3.2.3 Reagent-Feeding System ......................................................................... 32
3.2.4 Flue-Gas Supplying System ..................................................................... 35
3.2.5 Sampling and Analyzing System ............................................................. 36
3.3
Experimental Procedure ............................................................................... 37
3.3.1 Procedure and Analysis ............................................................................ 37
3.3.2 Validation of Experimental Setup Conditions.......................................... 39
Chapter 4 NO Reduction by Biomass Pyrolysis Products ................45
4.1
Introduction .................................................................................................. 45
4.2
Experimental Conditions ............................................................................. 45
V
Mechanism of Low-NOx Emission in Circulating Fluidized-Bed Decoupling Combustion
4.3
Results and Discussion ................................................................................ 46
4.3.1 NO Reduction Varying with Reagent Feeding Rate ................................ 46
4.3.2 NO Reduction Varying with SR ............................................................... 49
4.3.3 NO Reduction Varying with Reaction Temperature ................................ 53
4.3.4 NO Reduction Varying with Residence Time .......................................... 54
4.3.5 NO Reduction Varying with Flue Gas Composition................................ 55
4.4
Conclusions .................................................................................................. 61
Chapter 5 Synergetic Effect Among Pyrolysis Products in
Reducing NO .......................................................................63
5.1
Introduction .................................................................................................. 63
5.2
Experimental Conditions ............................................................................. 63
5.3
Results and Discussion ................................................................................ 65
5.3.1 Synergetic Effect of Binary Reagent ....................................................... 65
5.3.2 Synergetic NO Reduction Varying with Reaction Temperature .............. 70
5.3.3 Synergetic NO Reduction Varying with Residence Time ........................ 71
5.3.4 Synergetic NO Reduction Varying with Gas Species .............................. 72
5.4
Conclusion ................................................................................................... 76
Chapter 6 NO Reduction by Reagents Derived from Different Fuels.
..............................................................................................77
6.1
Introduction .................................................................................................. 77
6.2
Materials and Experimental Conditions....................................................... 77
6.2.1 Materials .................................................................................................. 77
6.2.2 Experimental Conditions ......................................................................... 79
6.3
Results and Discussion ................................................................................ 81
6.3.1 NO Reduction by Char Reagents and Effect of Ash Content .................. 81
6.3.2 NO Reduction by Tar Reagents and Model Tar Compounds ................... 88
6.4
Conclusions .................................................................................................. 98
Chapter 7 Conclusions and Recommendations .................................99
7.1
Conclusions .................................................................................................. 99
7.2
Innovation .................................................................................................. 101
7.3
Recommendations for Future Work ........................................................... 101
Nomenclatures .......................................................................................103
References ..............................................................................................105
Appendix A
Chemical Compositions of Tested Tar Reagents ...... 115
A.1 GC–MS Spectra .............................................................................................. 115
VI
Table of Contents
A.2 Identified Compounds of Tar .......................................................................... 116
Appendix B
Calibration Curves of Feeders for Different Reagents .
......................................................................................... 119
Acknowledgement .................................................................................121
Résumé ...................................................................................................123
VII
Chapter 1 Introduction
Chapter 1 Introduction
1.1 Background
Since the 20th century, the world has been improving so fast with the rapid
development of industries and technologies, as a result huge amounts of industrial
wastes are produced. For example, distilled spirit lees from beverage industries,
sawdust from the wood industries, mycelial wastes from medicine industries, sewage
sludge from wastewater plant and so on have already been the major resource of
biomass named industrial biomass wastes. Most of them are of similar properties with
high organic matter, high nitrogen and water contents, which cause a lot of
environmental problems and have very few effective utilization ways until now.
Fig. 1.1 Distilled spirit lees (DSL) disposal.
In term of beverage industries, China is a large spirits-producing country.
Therefore, the output of solid residue such as distilled spirit lees (DSL) generated in the
unique solid-state fermentation process (Fig. 1.1) is enormous all over the country. In
fact, DSL amounts to 20 million tons per year (Deng and Luo, 2004) and can be
considered as a good biomass resource due to its being rich in cellulose and
hemicellulose. Traditionally, the DSL have sufficiently high nutrition content for being
feedstuff or protein substrate of animals such as pig. With progress in the biotechnology,
the digestible nutrition in the lees becomes so low that it cannot meet the requirement
of animal feedstuff. Nowadays, except for apart used as the filler material for animal
feedstuff or as fertilizer, the DSL is mainly landfilled or discharged to the open air
1
Mechanism of Low-NOx Emission in Circulating Fluidized-Bed Decoupling Combustion
(Deng and Luo, 2004; Zhang et al., 1997). However, the high moisture in DSL, even
up to 60 wt. %, and the properties of easy putrescibility and strong acidity can cause
serious environmental problems, such as smelly gas release and underground water
pollution (Xu et al., 2009a). Therefore, highly reliable technologies for clean, rapid and
large-scale utilization of DSL are in a great demand in the spirits industry of China,
especially for large distiller factories.
The nature of rich in cellulose in DSL makes it hardly treated via biological
conversion technologies. The thermal conversion of the lees into the energy usable in
the distiller factories, such as steam or fuel gas, is thus considered to be viable. Burning
DSL to produce steam in fact not only limits the pollution as a result of DSL disposal
but also offers a part of energy required by distilled spirits production (Xu et al., 2007).
However, as a result of its relatively high N content (about 3 – 5 wt. % on a dry basis),
direct combustion of DSL via the traditional way has to release high NOx emission,
which is one of the main gas-phase pollutants released in fuel combustion, not only
injures human health but also forms acid rain and photochemical smog (Winter et al.,
1999; Calvert, 1997). The NOx content in the flue gas can even reach up to 550 ppm
during burning this material in a laboratory fluidized bed (Zhu et al., 2015).
In order to reduce NOx emission in combusting high-N biomass waste and also
improve the combustion efficiency of a conventional circulating fluidized bed, the
so-called circulating fluidized-bed decoupling combustion (CFBDC) technology has
been investigated and developed by our Advanced Energy Technology Laboratory
(AET Lab), Institute of Process Engineering (IPE), Chinese Academy of Sciences
(CAS). The technology has been well proven by an industrial system treating DSL. The
actual running data show that the NOx emission was lowered by about 70% comparing
to the traditional CFB combustion (Han et al., 2015; Yao et al., 2011; Xu et al., 2010),
making the NO content in its flue gas be 120 – 170 mg/Nm3 for the DSL containing N
of about 4.0 wt.%. This kind of technologies can also be applied to many other lees and
residues such as vinegar lees and Chinese herb residues generated in various light
industrial processes (Yao et al., 2011).
The CFBDC technology is based on the reaction decoupling concept which
separates the combustion process into drying/pyrolysis of fuel and combustion of
pyrolysis-generated char and volatile. Thus, the system is composed of a fluidized-bed
pyrolysis reactor and a riser combustor, the pyrolysis-generated volatile consisting of
non-condensable pyrolysis gas (py-gas) and condensable tar is sent to an intermediate
2
Chapter 1 Introduction
position of the riser combustor to allow its co-burning with char, as conceptualized in
Fig. 1.2. The co-burning of fuel pyrolysis products in such an intermediate position can
be considered as a reburning way that effectively reduces the NOx formed by burning
char in the bottom zone. Therefore, more fundamental studies refer to reburning
chemistry are suggested to further understand the low-NOx emission mechanism in
CFBDC system. This would facilitate the technology scale-up and also contribute to
update the technical designs for CFBDC.
Flue gas
Heated HCPs + unburnt char
Distilled
spirit lees
Py-gas & Tar
Riser
Combustor
Air
Fluidized
Bed
Pyrolyzer
Temperature-lowered
HCPs + char
N2 / Air
Fig. 1.2 Principle conception of circulating fluidized bed decoupling combustion (CFBDC).
1.2 Objectives and Significance
The approaches of the decoupling principle for innovating combustion
technologies were unquestionably effective, namely in term of lowering NOx emission.
The NOx reduction mechanisms in the developed coal/biomass combustion devices
have been systematically studied by AET Lab to determine better control strategies
associated with the technologies involving decoupling conception. Thereby, the
reduction effects of char and reducing gas on NO (as the main component of NOx in
most practical flue gas) were analyzed in detail (Cai et al., 2013; Dong et al., 2010,
2009, 2007; He et al., 2006). Recently, tar species derived from the pyrolysis of DSL
was found to reduce NOx significantly by the analysis in micro-fluidized bed reactor
(Song et al., 2014). However, the experimental conditions in earlier investigations were
actually not close enough to the reburning condition in CFBDC due to the limitations
3
Mechanism of Low-NOx Emission in Circulating Fluidized-Bed Decoupling Combustion
of batch or semi-batch reactors adopted. In addition, those studies are still far from fully
understanding the interactions occurred within the practice system since the combined
actions of NOx reduction in the reburning zone by different agents including char, tar
and py-gas have not been previously considered. Above all, the complexity of the NO
reduction reactions required that further experimental work must be carried out in order
to understand some key aspects of the process. Therefore, it is highly worthwhile to
deepen such studies for further understanding the mechanism of low-NOx emission in
CFBDC treating not only DSL but also other fuels such as sawdust or coal. To
implement this plan, a continuous drop-tube reactor (DTR) was indeed adopted to
facilitate the investigations on the characteristics of NO reduction using char, tar and
py-gas from pyrolysis of different fuels as reagents, these aim to
(i)
figure out the dominant NO reduction reactions for CFBDC,
(ii) provide the optimal conditions for operating CFBDC system in term of
achieving high NOx reduction,
(iii) reveal the synergetic effect among char, tar and py-gas on NO reduction
occurring during their reburning in CFBDC,
(iv) understand the combined homogeneous–heterogeneous reaction mechanism
for NO reduction,
(v) understand the different NO reductions for tars, chars derived from different
fuels and the contributions of their constituents to the achieved NO reduction.
1.3 Thesis Outline
This thesis discusses basically on two following topics
(i)
reduction of NO by DSL pyrolysis products including char, tar and py-gas in
both individual and combined actions,
(ii) reduction of NO by reagents derived from different fuels in comparison with
that by DSL-derived products.
The contents are divided into seven chapters. The first chapter served as an
introduction where the brief background of CFBDC are given, followed by the research
objectives and approach.
Chapter 2 provides a literature review about the theoretical background and
current state of research essential for the discussion of experiment results.
Chapter 3 introduces the materials and the main experimental techniques used in
4
Chapter 1 Introduction
this study. Namely, the preparation of NO-reduction reagents from DSL, the design of
experimental apparatus, the procedure and analysis of experiments were described
in detail.
Chapter 4 begins presenting the results of this study. The NO reduction
characteristics of DSL-derived char, tar and py-gas are shown and discussed, from
which the influences of reagent feeding rate, reburning stoichiometric ratio (SR),
reaction temperature, residence time, initial composition of flue gas on NO reduction
by each reagent are put into evidence.
Chapter 5 covers the synergetic effect of reagents on NO reduction. The results of
NO reduction tests using the mixtures of binary reagents among char, tar and py-gas
derived from DSL are given and discussed in function of SR, temperature and residence
time. Moreover, the effects of gas species in py-gas such as CO, H2, CH4 on NO
reduction by char/py-gas mixture are presented.
Chapter 6 examines the NO reduction by tars, chars derived from different fuels
such as such as SD and XF coal. The results in this chapter are brought together with
those in Chapter 4 in order to compare the capabilities of different reagents for reducing
NO. The difference in NO reduction by chars is discussed based on the analysis of
catalytic matter in ashes, while the contribution of some components in tars to the
overall NO reduction is provided in addition to explain the reactivity of tars for NO
removal.
Chapter 7 briefly summarizes the key conclusions of this study and provides a few
recommendations for future research directions.
5
Chapter 2 Literature Review
Chapter 2 Literature Review
2.1 Nitric Oxides
Nitrogen oxides (NOx), some of the main gas-phase pollutants released in fuel
combustion, are a very interesting and important family of air pollutant. NOx not only
injures human health but also forms acid rain and photochemical smog (Winter et al.,
1999; Calvert, 1997). Therefore, a strict legislation is thus being considered or has been
implemented by many countries, including China, to lower the emission of NOx.
2.1.1 Sources of NOx
There are two sources of NOx emission generated by human activities such as
mobile sources and stationary sources. Automobiles and other mobile sources
contribute about half of the NOx that is emitted, while electric power plant boilers
produce about 40% of the NOx emissions from stationary sources (United States
Environmental Protection Agency, 1999). The substantial emissions are also added by
such sources as industrial boilers, incinerators, gas turbines, reciprocating spark ignition
and diesel engines in stationary sources, iron and steel mills, cement manufacture, glass
manufacture, petroleum refineries, and nitric acid manufacture. In addition, biogenic or
natural sources of nitrogen oxides including lightning, forest fires, grass fires, trees,
bushes, grasses, and yeasts are also involved in the global NOx emission. These various
sources produce differing amounts of NOx but almost three-quarters of the total amount
of NOx emission is contributed by human activities through combustion of fossil and
alternative fuels (including field burning and forest fires) (Topsoe, 1997; Bosch and
Janssen, 1988).
2.1.2 NOx Emission in China
China is the largest NOx emission country in Asia contributing 41% – 57% of
Asian NOx emissions (Fei et al., 2016; Wang et al., 2014; Wang and Hao, 2012; Zhao
et al., 2008; Ohara et al., 2007; Mauzerall et al., 2005). With the rapid growth of energy
consumption, NOx emissions were estimated to more than double from 11.0 Mt in 1995
to 26.1 Mt in 2010, with an annual growth rate of 5.9%. Power plants, industry and
transportation were major sources of NOx emissions, accounting for 28.4%, 34.0%, and
25.4% of the total NOx emissions in 2010, respectively (Zhao et al., 2013b). In 2014,
7
Mechanism of Low-NOx Emission in Circulating Fluidized-Bed Decoupling Combustion
2.5 million tons of NOx were emitted from industrial boilers, which accounted for
12.3% of total Chinese NOx emissions. Industrial boilers are the third largest emission
source, after power plants and vehicles (Ministry of Environmental Protection of the
People’s Republic of China, 2014). Based on current legislation and implementation
status, defined as a business as usual (BAU) scenario according to Zhao et al. (2013b),
NOx emissions in China are estimated to increase by 36% in 2030 from 2010 level. In
detail, the trend in NOx emissions and that prediction for 2020 and 2030 of each
province in China are listed in Table 2.1.
Table 2.1 Provincial NOx emissions during 2005 – 2030 (Mt) in China (Zhao et al., 2013b).
8
Province
2005
2010
Beijing
Tianjin
Hebei
Shanxi
Inner Mongolia
Liaoning
Jilin
Heilongjiang
Shanghai
Jiangsu
Zhejiang
Anhui
Fujian
Jiangxi
Shandong
Henan
Hubei
Hunan
Guangdong
Guangxi
Hainan
Chongqing
Sichuan
Guizhou
Yunnan
Tibet
Shaanxi
Gansu
Qinghai
Ningxia
Xinjiang
Total
0.41
0.31
1.35
0.84
0.70
0.90
0.46
0.60
0.41
1.49
1.08
0.68
0.43
0.36
1.97
1.40
0.65
0.64
1.35
0.39
0.06
0.27
0.60
0.42
0.36
0.01
0.46
0.32
0.06
0.18
0.34
19.48
0.48
0.41
1.62
1.05
1.16
1.15
0.64
0.72
0.47
1.75
1.27
0.99
0.73
0.50
2.52
1.86
0.96
0.84
1.76
0.58
0.09
0.46
0.98
0.52
0.52
0.02
0.68
0.46
0.09
0.30
0.49
26.05
Business as Usual (BAU) Scenario
2020
2030
0.47
0.46
0.46
0.49
2.11
2.30
1.35
1.50
1.52
1.70
1.40
1.56
0.68
0.78
0.88
0.97
0.59
0.65
2.07
2.22
1.54
1.63
1.21
1.40
1.02
1.16
0.62
0.74
3.01
3.13
2.16
2.45
1.09
1.24
1.04
1.21
2.16
2.40
0.72
0.84
0.12
0.14
0.52
0.61
1.10
1.27
0.69
0.81
0.63
0.75
0.03
0.03
0.86
1.02
0.59
0.70
0.10
0.12
0.40
0.46
0.56
0.63
31.69
35.35
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