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Cornerstone for a Sustainable Europe

Summary of the technical report

A Competitive

And effiCient

Lime industry

In 2011, the European Commission published a roadmap for moving to a competitive low carbon economy by 2050. It outlines an ambitious CO 2 reduction goal whilst keeping European industry competitive. We operate in a globalised economy, with global competition. Given the difference in energy costs and the rather flat growth curves of the European economies, this a bold goal.

The European lime industry, as energy and carbon intensive sector, looked at a wide range of options to contribute to the 2050 objective and move towards a competitive low carbon economy. Over the past 20 years, the European lime industry has lowered its emissions substantially, mainly by modernising plants and adjusting the fuel mix.

We started an in-depth analysis of how and what is possible now and in the future. We looked at all possible available options: substituting fuels, efficiency measures and even carbon capture.

We identified many areas where we can make a difference. However, lime production is different from many other industries. Although, about a third of emissions are caused by burning fuels to heat the kilns and some electricity is used for grinding and other mechanical operations, the bulk of our emissions come from the raw material used: limestone. When heated, a chemical reaction takes place where limestone is transformed into lime and CO 2 is released.

These process emissions are inevitable and fairly constant per tonne of lime. Unless the carbon is captured, and used or stored, but its economic feasibility has to be looked at.

Lime is enabling key material for many sectors. Its unique properties enable other industries to reduce their carbon footprint. For example hydrated lime in asphalt makes transport more energy efficient transport. However, in this roadmap, we focused our research on what we can do ourselves.

Our industry is closely interconnected with other industries. We, therefore, looked at external factors and how they could impact us. Lime is used in a variety of industrial processes and its sustainability is intrinsically linked to that of others. We also examined the potential impact of the cost of carbon on the European lime industry and the risk of carbon leakage.

The priority of the sector is to deliver quality products manufactured in a sustainable way and respectful of the environment. The lime industry would like to call upon the EU to put in place the necessary instruments that will allow th economy to become a low carbon one, whilst maintaining the competitiveness of the European industry by supporting its role in a complete value chain. We outlined a series of possible policy measures to support the development of innovative technologies and keep Europe’s industrial landscape economically vibrant.

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LIME INDUSTRY

Introduction

Introduction

Lime is an essential but often unseen ingredient. Not only does it help the construction and manufacturing industries optimise their products, but it also supports the drinking water, food and farming sectors with its versatile and unique characteristics.

It is the only mineral product that can be used to produce steel and sugar in the same day! Lime is a highly important and diverse substance, due to its alkalinity and ability to purify and neutralise.

Lime is an important, and often irreplaceable component of many industrial sectors; from steel manufacturing to the construction materials, chemical industries and paper pulp.

Even though it was discovered in ancient times, today it is manufactured using the latest industrial processes and techniques. Lime products are used in a wide variety of applications in Europe, and worldwide. The average EU citizen indirectly uses around 150 g/day of lime products.

“It is the only mineral

product that can be used

to produce steel and

sugar in the same day!

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LIME INDUSTRY

What is Lime?

What is Lime?

”

OVERVIEW OF CUSTOMER MARKETS AND FUNCTIONALITY OF LIME PRODUCTS

IRON AND STEEL

**- Removing impurities

• Enhancing productivity**

OTHER INDUSTRIAL

CUSTOMERS

**- Removing impurities from sugar

• Glass and paper production**

CHEMICAL INDUSTRY

- Feedstock for calcium

carbide

- Versatile filler in paint,

pharmaceutical and PVC

- PH Correction

AGRICULTURE

**- Nutrient in fertilizer

• Animal nutrition
• Animal hygiene: Prevent**

diseases

EXPORT

CONSTRUCTION

Lightweight and high

insulation construction

materials aggregate, filler

and bonding agent

CIVIL ENGINEERING

- Improving stability and load bearing

capacity of soil

- Improve durability asphalt

ENVIRONMENTAL

PROTECTION

- Drinking water treatment:

remove heavy metals

- Wastewater treatment:

remove impurities

- Flue gas purification

38%

11% 7%

16%

3%

7%

14%

4%

“Used in many products

for everyday life, lime is

probably the most versatile

natural mineral product.

”

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LIME INDUSTRY

What is Lime used for?

How is Lime made?

1. Extraction

• In the quarry, controlled explosions used to break up limestone or chalk rock. This can dislodge up to 30,000 tonnes of rock in one explosion.
• The broken rock is then picked up at the quarry face by huge, mechanised excavators.

How Lime is Made

2. Crushing and Screening

• Trucks then tip the rock into crushers, which break down the rock into smaller pieces.
• Screeners sort and separate the rock pieces into different sizes.

5. The Kiln

• The rock is heated to 800ºC in the preheater and then from 1200ºC to 2000ºC to make lime.
• The burn temperature and time in the kiln depends on the type of rock that is used as the raw material.
• The kiln can either be horizontal or vertical.

6. Cooling

• The lime that leaves the kiln is cooled with air.

8. Storage and

Dispatch

• Finished lime products are safely wrapped, packaged and stored on site.
• They are then sent to the customer by road, rail and even boats overseas.

7. Hydration

• Sometimes after cooling, water is added to lime to make hydrated lime.
• The type of lime that is made depends on what the customer is using it for.

4. Fuels

• Different types of fuel are added to power the kiln.

3. Emissions Control

• A number of filters and scrubbers control the dust and gases generated from

1. Extraction burning the rock.

• In the quarry, controlled explosions used to break up limestone or chalk rock. This can dislodge up to 30,000 tonnes of rock in one explosion.
• The broken rock is then picked up at the quarry face by huge, mechanised excavators.

How Lime is Made

2. Crushing and Screening

• Trucks then tip the rock into crushers, which break down the rock into smaller pieces.
• Screeners sort and separate the rock pieces into different sizes.

5. The Kiln

• The rock is heated to 800ºC in the preheater and then from 1200ºC to 2000ºC to make lime.
• The burn temperature and time in the kiln depends on the type of rock that is used as the raw material.
• The kiln can either be horizontal or vertical.

6. Cooling

• The lime that leaves the kiln is cooled with air.

8. Storage and

Dispatch

• Finished lime products are safely wrapped, packaged and stored on site.
• They are then sent to the customer by road, rail and even boats overseas.

7. Hydration

• Sometimes after cooling, water is added to lime to make hydrated lime.
• The type of lime that is made depends on what the customer is using it for.

4. Fuels

• Different types of fuel are added to power the kiln.

3. Emissions Control

• A number of filters and scrubbers control the dust and gases generated from burning the rock.

1. Extraction

• In the quarry, controlled explosions used to break up limestone or chalk rock. This can dislodge up to 30,000 tonnes of rock in one explosion.
• The broken rock is then picked up at the quarry face by huge, mechanised excavators.

How Lime is Made

2. Crushing and Screening

• Trucks then tip the rock into crushers, which break down the rock into smaller pieces.
• Screeners sort and separate the rock pieces into different sizes.

5. The Kiln

• The rock is heated to 800ºC in the preheater and then from 1200ºC to 2000ºC to make lime.
• The burn temperature and time in the kiln depends on the type of rock that is used as the raw material.
• The kiln can either be horizontal or vertical.

6. Cooling

• The lime that leaves the kiln is cooled with air.

8. Storage and

Dispatch

• Finished lime products are safely wrapped, packaged and stored on site.
• They are then sent to the customer by road, rail and even boats overseas.

7. Hydration

• Sometimes after cooling, water is added to lime to make hydrated lime.
• The type of lime that is made depends on what the customer is using it for.

4. Fuels

• Different types of fuel are added to power the kiln.

3. Emissions Control

• A number of filters and scrubbers control the dust and gases generated from burning the rock.

1. Extraction

• In the quarry, controlled explosions used to break up limestone or chalk rock. This can dislodge up to 30,000 tonnes of rock in one explosion.
• The broken rock is then picked up at the quarry face by huge, mechanised excavators.

How Lime is Made

2. Crushing and Screening

• Trucks then tip the rock into crushers, which break down the rock into smaller pieces.
• Screeners sort and separate the rock pieces into different sizes.

5. The Kiln

• The rock is heated to 800ºC in the preheater and then from 1200ºC to 2000ºC to make lime.
• The burn temperature and time in the kiln depends on the type of rock that is used as the raw material.
• The kiln can either be horizontal or vertical.

6. Cooling

• The lime that leaves the kiln is cooled with air.

8. Storage and

Dispatch

• Finished lime products are safely wrapped, packaged and stored on site.
• They are then sent to the customer by road, rail and even boats overseas.

7. Hydration

• Sometimes after cooling, water is added to lime to make hydrated lime.
• The type of lime that is made depends on what the customer is using it for.

4. Fuels

• Different types of fuel are added to power the kiln.

3. Emissions Control

• A number of filters and scrubbers control the dust and gases generated from burning the rock.

1. Extraction

• In the quarry, controlled explosions used to break up limestone or chalk rock. This can dislodge up to 30,000 tonnes of rock in one explosion.
• The broken rock is then picked up at the quarry face by huge, mechanised excavators.

How Lime is Made

2. Crushing and Screening

• Trucks then tip the rock into crushers, which break down the rock into smaller pieces.
• Screeners sort and separate the rock pieces into different sizes.

5. The Kiln

• The rock is heated to 800ºC in the preheater and then from 1200ºC to 2000ºC to make lime.
• The burn temperature and time in the kiln depends on the type of rock that is used as the raw material.
• The kiln can either be horizontal or vertical.

6. Cooling

• The lime that leaves the kiln is cooled with air.

8. Storage and

Dispatch

• Finished lime products are safely wrapped, packaged and stored on site.
• They are then sent to the customer by road, rail and even boats overseas.

7. Hydration

• Sometimes after cooling, water is added to lime to make hydrated lime.
• The type of lime that is made depends on what the customer is using it for.

4. Fuels

• Different types of fuel are added to power the kiln.

3. Emissions Control

• A number of filters and scrubbers control the dust and gases generated from burning the rock.

1. Extraction

• In the quarry, controlled explosions used to break up limestone or chalk rock. This can dislodge up to 30,000 tonnes of rock in one explosion.
• The broken rock is then picked up at the quarry face by huge, mechanised excavators.

How Lime is Made

2. Crushing and Screening

• Trucks then tip the rock into crushers, which break down the rock into smaller pieces.
• Screeners sort and separate the rock pieces into different sizes.

5. The Kiln

• The rock is heated to 800ºC in the preheater and then from 1200ºC to 2000ºC to make lime.
• The burn temperature and time in the kiln depends on the type of rock that is used as the raw material.
• The kiln can either be horizontal or vertical.

6. Cooling

• The lime that leaves the kiln is cooled with air.

8. Storage and

Dispatch

• Finished lime products are safely wrapped, packaged and stored on site.
• They are then sent to the customer by road, rail and even boats overseas.

7. Hydration

• Sometimes after cooling, water is added to lime to make hydrated lime.
• The type of lime that is made depends on what the customer is using it for.

4. Fuels

• Different types of fuel are added to power the kiln.

3. Emissions Control

• A number of filters and scrubbers control the dust and gases generated from burning the rock.

1. Extraction

• In the quarry, controlled explosions used to break up limestone or chalk rock. This can dislodge up to 30,000 tonnes of rock in one explosion.
• The broken rock is then picked up at the quarry face by huge, mechanised excavators.

How Lime is Made

2. Crushing and Screening

• Trucks then tip the rock into crushers, which break down the rock into smaller pieces.
• Screeners sort and separate the rock pieces into different sizes.

5. The Kiln

• The rock is heated to 800ºC in the preheater and then from 1200ºC to 2000ºC to make lime.
• The burn temperature and time in the kiln depends on the type of rock that is used as the raw material.
• The kiln can either be horizontal or vertical.

6. Cooling

• The lime that leaves the kiln is cooled with air.

8. Storage and

Dispatch

• Finished lime products are safely wrapped, packaged and stored on site.
• They are then sent to the customer by road, rail and even boats overseas.

7. Hydration

• Sometimes after cooling, water is added to lime to make hydrated lime.
• The type of lime that is made depends on what the customer is using it for.

4. Fuels

• Different types of fuel are added to power the kiln.

3. Emissions Control

• A number of filters and scrubbers control the dust and gases generated from burning the rock.

eXtrACtion

rAW mAteriALs

CrusHinG And

sCreeninG

WeiGH Hopper

reversinG

system

CooLinG

to storAGe

CALCininG

preHeAtinG

Lime dispAtCH By roAd

Lime storAGe

And BAGGed

produCts

dust

CLeAninG

fueL

LAnCes

CooLinG

Air

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LIME INDUSTRY

How is Lime made?

Energy Use

HEAT CONSUMPTION

Producing lime requires heating limestone between 900°C and 1200°C. Maintaining these kinds of temperatures requires a substantial amount of energy. In 2010, the average fuel consumption is 4.25 GJ/tonne of quicklime.

Calcination is the most energy intensive step in the lime production process, thus the energy efficiency of the kiln has a large impact on emissions. Thanks to the optimisation of the production process, the lime industry has made a lot of progress in terms of energy efficiency, nevertheless, we looked at a multitude of ways to reduce energy consumption even further.

However, we are limited by the laws of physics and chemistry. The theoretical minimum energy required for the chemical reaction that transforms limestone to take place, is 3.18 GJ/ tonne of quicklime. This number assumes complete conversion of limestone into lime. In reality, not all limestone is converted to lime. For example, limestone typically contains 1% of water which evaporates in the kiln and leads to increased energy use.

Other aspects, such as the specification of the desired lime, grain size, humidity of the limestone, fuel quality and residual CO 2 content in the lime product all play a role as well.

Nevertheless, the type of kiln has a major impact on the energy consumption per tonne of lime.

The vast majority of plants in Europe are equipped with modern, energy efficient kilns and the less efficient ones are continually improved or will be replaced over time. However, as plants modernise

and technology evolves, we will achieve improved thermal efficiency but options are very limited, not least by the theoretical minimum energy input.

Kiln orientation: Kiln type:

Heat use / consumption for quicklime production (GJ/tonne):

Vertical

Parallel flow regenerative kilns (PFRK) 3.2-4.

Annular shaft Kilns (ASK) 3.3-4.

Mixed Feed Shaft Kilns (MFSK) 3.4-4.

Horizontal

Long Rotary Kilns (LRK) 6.0-9.

Rotary Kilns with preheater (PRK) 5.1-7.

Other Kilns 3.5-7.

OVERVIEW OF THE MINIMUM AND MAxIMUM HEAT CONSUMPTION PER KILN TYPE FOR qUICKLIME PRODUCTION (JRC, 2013 (BREF))

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LIME INDUSTRY

Energy Use

FUELS

Currently, the European Lime industry uses

a wide variety of fuels, including fossil fuels

(natural gas, fossil solid fuels and oil), waste

or biomass.

Fuel use can influence the product quality.

Certain fuels can not be used for specifics application.

ELECTRICITY CONSUMPTION

The electricity consumption in lime manufacturing is relatively low. Electricity is mainly used for operating some of the kiln equipment and mechanically crushing the limestone. Electricity consumption varies, but it is estimated at ±60 kWh/t.

NATURAL GAS

BIOMASS

WASTE

OIL

FOSSIL SOLID FUELS

34%

51%

5%

8%

2%

FUEL MIX 2010, (EULA, 2012).

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LIME INDUSTRY

Energy Use

Theoretical reduction potential of fuel use and

projected combined effect in 2050 for quicklime

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LIME INDUSTRY

Reducing our emissions

FUEL SAVINGS

Over the past decades, the European lime industry has invested heavily in energy savings technology and continuously improved plants to reduce their energy consumption.

While the heat of reaction, the energy required for the chemical reaction to take place – for a typical quicklime quality – is 3.03 GJ/tonne. Theoretically, the potential for energy efficiency improvement is, therefore, limited to 29%; the rest of the fuel is needed to provide the energy

for the chemical reaction. Limestone always contains impurities and a driving force is always required to get the reaction going.

We estimate that implementing existing technology and future innovation could lead to a reduction of 16% in fuel intensity by 2050. This would be achieved mainly by building new

• highly efficient – kilns, and retrofitting existing kilns. By 2030, the projected total decrease of fuel intensity is estimated to be 8%.

Reducing our emissions

The main methods of this increased fuel

efficiency would be

Switching from horizontal to vertical kilns

Lime can be produced in different kinds of kilns.

Over the past decades, new kiln types have been

developed and existing kilns have been improved.

Newer vertical kilns are considerably more energy

efficient than horizontal kilns. In Europe, 80% of

lime is produced in vertical kilns. Some existing

horizontal kilns have been refurbished, but they

cannot achieve the same energy efficiency as a new vertical kiln. In the coming years, old kilns are likely to be replaced by new, more efficient ones.

Installing heat exchangers in horizontal kilns

In horizontal kilns heat exchangers can be used to recover some of the heat from the flue gases produced in the kiln and use this heat to preheat the feed limestone. This could generate – on average – a fuel saving of around 25%. However, this potential reduction is only applicable to horizontal kilns.

Innovation

Projected

combined

effect for

quicklime

13% in 2050

Theoretical potential

- Can partially be avoided

Heat of reaction

- Cannot be avoided

29%

71%

Fuel use (GJ/tonne quicklime)

Horizontal kilns

PFRK

Preheater

Vertical kilns PFRK

Improvents in all kilns

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LIME INDUSTRY

Reducing our emissions

Switching from vertical kilns to vertical kilns Parallel flow regenerative kilns

There are several types of vertical kilns. The Parallel Flow Regenerative (PFRK) type is the most efficient one. However, they cannot always produce all types of products to fully satisfy market needs and sometimes cannot process the smallest particles; therefore, they are not always the best solution from a resource efficiency point of view.

Further innovation could increase the applicability of PFRKs enabling them to handle smaller particles and, thus, making them more resource efficient.

Improved use of Waste Heat

Waste heat from the kiln can be used to dry limestone or in the milling process. In addition, the waste heat can be used in other industrial processes, in other sectors with a heat demand or they can be used to heat buildings and generate electricity. However, many lime plants are located in remote rural areas, which makes distributing the excess heat to other industries or as a residential heating source difficult at times.

Energy recovery in hydration

The production of hydrated lime and dolime is an exothermal reaction, i.e. it generates heat. The heat resulting from the production of hydrated lime amounts to about 1.2 GJ/tonne of CaO. This heat could be used in industrial processes or heating buildings if there is such a demand in the remote areas where the plants operate. This option will require further R&D to work out how to extract the heat without affecting the production process and quality of the product.

Other Measures

A range of other measures could also lead to increased fuel efficiency. These include efficient kiln insulation lining, optimised combustion processes improved process and input control, optimal change-over and further improved maintenance procedures.

Electricity Savings

Significant steps have been taken over the years to reduce our electricity consumption. Increasingly efficient engines and other technological progress have made a real difference but more stringent environmental legislation and increased controls in modern plants have offset some of these gains. Nerveless, we remain committed to finding ways to reduce our power consumption. The efficiency of motor systems is – conservatively - assumed to have a saving potential of 10%. Optimizing cooling and grinding for instance could lead to further energy efficiency gains.

“Optimizing cooling and

grinding for instance could

lead to further energy

efficiency gains.

”

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LIME INDUSTRY

Reducing our emissions

Use of gas instead of solid fossil fuels

The European lime industry currently uses

natural gas for about one third of its energy

needs. Switching from solid fossil fuels to

natural gas would reduce the CO 2 intensity of

lime production although the gas network may

be a concern, given the location of our plants.

Within the framework of this exercise, we

assumed that all solid fuels used today would

be replaced by natural gas. This can potentially

reduce the average emission factor of the fuel

mix by 30%.

This switch is dependent on a steady, secure

and affordable supply of natural gas and will be

affected by on a series of external factors such

as potential price hikes caused by a switch to

natural gas by the power sector or, inversely,

lower gas prices, as European unconventional

gas becomes available.

Use of waste as a fuel

Certain types of lime kilns are suited for the use

of waste as a fuel source. The European lime

industry is committed to remaining an important

factor in the circular economy. The use of waste

as a fuel source will continue but is conditional

upon the availability of the right kind of waste

and a regulatory environment that permits the

use of waste as a fuel.

Use of biomass as fuel

Different forms of biomass can be used as a fuel

in kilns. There are some technical restrictions,

especially in the fuel efficient vertical kilns, as to

the type of biomass that can be used, but ongoing innovation could ensure biomass will remain a fuel source of the European lime industry.

One of the ways to overcome the difficulties using biomass would be to convert it to syngas first. Using similar technology kilns could even be fuelled by biogas, sewage gas or landfill gas.

Use of electricity to heat kilns

Electricity could theoretically be used in the future to heat kilns. The European Commission’s Energy Roadmap plans a total decarbonisation of power, so this would result in a substantial reduction of our emissions. However, with current and foreseen power prices, this option is not economically viable. Moreover, this option is not yet technically feasible for the moment and will require further R&D.

However, the situation would be different in times of oversupply of electricity, resulting in cheap or even free electricity. Using electricity to heat the kilns might then be feasible and could help to bring supply and demand in equilibrium.

Solar heat

Solar heat could potentially be used, in some countries, to heat the kilns but they have to be heated to at least 900°C. In the future, high- temperature Central Receiver Systems (CRS) with pressurised air could reach temperatures up to 1000°C. However, this technology is still in an experimental phase, would require further research, and is only suitable for Southern Europe.

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LIME INDUSTRY

“The European lime industry is committed to

remaining an important part of the value chain

contributing to the circular economy.

”

Reducing our emissions

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LIME INDUSTRY

Reducing our emissions

A lime producer partnered in the Agical+ research project (financed under the European Commission LIFE+) that aimed at making use of the lime and glass sectors CO2 emissions. This project looked into an innovative solution, based on algae culture and biomass production, which would allow for the CO2 capture of lime or glass furnace fumes and the production of biofuel that could be used within the furnaces during the production process.

If applied at full-scale, such technology might significantly reduce CO2 emissions and consumption of fossil fuels related to lime and glass production industries. However, the economic analysis done in the project revealed that the cost of the biofuel produced would be around €650/GJ, or around 100-times more expensive than commercially traditional energy resources (natural gas, heavy fuel).

BIOFUEL PRODUCTION FROM CO2 EMISSIONS FROM LIME PRODUCTION

Storage or Utilization?

Assuming that the barriers of technical and

economic feasibility as well as social acceptance

have been overcome, the other big question is

what to do with captured CO 2. Two options are

available: storage or utilisation:

Storage

Storage involves transporting the CO 2 to a

geographically suitable location and storing it

underground. Currently, lime plants are typically

located right next to the limestone quarry, not

clustered in large industrial agglomerations. Transport

costs – to overcome the distance between the lime

plant where it is captured and the location where it is

stored – as well as any additional piping infrastructure

can add significantly to the capture costs.

Storage locations would need to be developed and

maintained and public and regulatory acceptance of

CO 2 storage still needs to be overcome.

Utilization The business case for capturing carbon, could be improved in case the captured CO 2 could be used, rather than stored. Storage costs could be saved, and it might get a financial value. The lime industry itself will not be able to use the it, but the business case to capture the CO 2 could benefit from others using it. A lot of research is currently devoted to developing new uses of CO 2 , including:

• Using it to produce fuels/hydrocarbons.
• Transforming CO 2 into inert carbonates, to be used, for example, as construction material.
• Using it as a feedstock for the production of polymers.
• Applying CO 2 to enhance recovery of fossil fuels (oil, gas).

Many of these applications are, however, only at research stage for the moment.

“If capturing carbon is the key to substantially

lower emissions, it does represent a real challenge

in terms of cost.

”

CARBONATION

Although not a traditional abatement measure, and not within the scope of our analysis, it is important to note that during the lifetime of products in which lime is applied, CO 2 from the atmosphere is captured (basically reversing the reaction in which lime is produced from limestone).

If atmospheric CO 2 has good access to the material, as is the case for example in some building materials, the lime, or the new material can reabsorb CO 2. This so-called “carbonation” partly closes the loop starting with CO 2 process emissions during lime production.

Carbonation is highly dependent on the application; in some applications the main carbonation takes place within five years, in other applications it takes longer. For example, for lime mortars, it is estimated that within 100 years, 80-92% carbonation will take place.

Pathway to 2050

Taking into account the unique emission profile of the lime industry, the type of plants in operation today and the possible savings, we have mapped a possible carbon reduction roadmap from 2010 to 2030 and 2050.

Possible development of the carbon intensities of lime production for 2030 and 2050, compared to 2010. Direct emissions

only, which form about 99% of total emissions. Green bars reflect process emissions, blue bars reflect fuel emissions and the

striped blue block indicates energy efficiency abatement. The orange bar reflects the – unknown – effect of natural carbonation.

The arrows (apart from the arrows in the carbonation part) indicate the technical potential of emission reduction options.

DECARBONISATION TOWARDS 2050: RELATIVE DIRECT CARBON INTENSITY (99% OF TOTAL EMISSIONS)

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%

0%

?

? Carbonation??

Fuel switch fossil

solid fuels to gas

Fuel switch fossil

solid fuels to gas

Further

decarbonisation

of the fuel mix

Arrows indicate a hypothetical deployment of Fuel emissions abatement options, intended as a thought experiment

Process emissions Energy efficiency improvement

CCU AND CCS

Relative direct carbon intensity (%)

2010 2030 2050

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LIME INDUSTRY

Reducing our emissions