Basic research for developing new ecological MgO-based binding systems acting as a carbon sink – LIECO,
CEEX-M1-C2-934

1. Information:

1.1 Client : The Politehnica Management Agency of Scientific Research, Innovation and Technology Transfer, Bucharest

1.2. Project Coordinator : CEPROCIM S.A. Bucuresti

ROMANIA, 6 Bucharest, # 6 blvd. Preciziei, code 062203 phone: +(4021) 318 88 84; 318 88 90; 318 88 93. fax: +(4021) 318 88 76; 318 88 94. E-mail: office@ceprocim.ro; res@ceprocim.ro Web: www.ceprocim.ro

1.3 Partners :

Partner 1: The National Institute of Research and Development for Metals and Radioactive Resources

Partner 2: PROCEMA RESEARCH SRL

Partner 3: University Politehnica of Bucharest, Centre of Research and Expertise for Special Materials

1.4. Duration: 13th September 2006-15th September 2008

1.5. Description

1.5.1. Scope:

The main purpose of the LIECO Project is to generate knowledge by way of unfolding scientific
research activities within national partnerships regarding the development of a new cementitious
system based on OPC-reactive magnesia-pozzolana.

1.5.2. Summary:

The new cementitious systems with high quality and ecological and economical performances will involve lower energy consumption than Portland cement by approx. 25%. Being able to capture and sequestrate the CO2 from the air, the new cementitious systems will have the advantage of being environmentally friendly.
The new cementitious systems will involve lower heat energy consumption than ordinary Portland cement due to a number of aspects:

• Substituting reactive magnesia for Portland cement clinker in varying ratios. Reactive MgO
  retains a large amount of thermal energy.
• Increasing the pozzolana ratio in the binder as compared to the present-day cement sorts. The
  fact allows replacing the clinker up to a considerable ratio.

In recent years, the cement industry around the world is facing a major environmental problem, namely, the emission of CO2 which has a particularly negative impact on the greenhouse effect.
Manufacturing ecological binders in the OPC-reactive magnesia-pozzolana system allows reducing the amount of CO2 in the atmosphere.

Reducing the CO2 emissions due to decreasing the heat consumption, and therefore diminishing the consumption of fuel

Absorption of an amount of CO2 from the air, during the hardening of the cementitious system, by way of the carbonation undergone by Mg(OH)2.

1.5.3. Objectives:

Developing new cement sorts based on other compositional systems than Portland cement. Such systems include reactive magnesia which has proved positive effects on the environment.

1.5.4. Envisaged results:

Manufacturing for the first time in Romania binders in the OPC-reactive magnesia-pozzolana system featuring high quality performances

Dissemination of the obtained results

Filing applications for patents of the obtained products

1.6. Staff involved in the Project :

• Scientific Researchers, Grade 1: Six individuals
• Scientific Researchers, Grade 2: Five individuals
• Scientific Researchers, Grade 3: Three individuals
• Scientific Researchers: Six individuals
• Engineers: Six individuals

In total eleven titles of doctor and eight aspirants at a doctor’s title – 11

2. Stages. Activities. Results

2.1. Stage I – Documentary study regarding the elaboration of new methods, procedures and modalities to manufacture new ecological binding systems containing reactive magnesia

2.2. Stage II – Investigating the materials which are potential sources of ecological binding systems

2.3. Stage III – Establishing a correlation between the chemical and structural composition and the quality of ecological binders in the OPC-reactive magnesia-pozzolana system

2.4. Stage IV – Experimental investigations for developing ecological binders in the system OPC-reactive magnesia-pozzolana

2.5. Stage V – Practical applications of the obtained results

3. Results

3.1. Stage I
The result of the first stage was a study regarding ecological binding systems containing reactive magnesia.

Literature search has materialised into the following information:

• Modern approach in developing binding systems in the building materials industry
• Investigating the composition and structure of the new binding systems over the usual binding systems
• New methods, procedures and ways to obtain binders in the OPC-reactive magnesia-pozzolana system
• Methods of manufacture and characteristics of the reactive magnesia
• Mechanisms of the hardening processes in usual binding systems and in the new systems
• Thermodynamics of the carbonation reactions in the Portland cement and ecological binding systems
• Benefits of manufacturing the new ecological binding systems based on reactive magnesia

3.2. Stage II
This study presents in detail the natural materials used to obtain reactive magnesia and, also, pozzolana and clinker.
It was obtained the following information:
– a natural material which can be obtained reactive magnesia are:
– brucite which can be found in deposits along with other minerals such as calcite or dolomite.
The proportion of MgO varies from 16% to 65%, depending on the deposit composition;
– magnesite: MgO content can reach 42-46% in the representative deposits as that from Screechowl Creek – west mount Hut;
– dolomite, which contains18-22% MgO, depending on the nature of the deposit.
Pozzolana may be:
– natural – volcanic tuff with a content of 40-64% SiO2 reactive;
– Diatomite, with 40-69% SiO2 reactive;
– Bentonite, with 25-49% SiO2 reactive;
– Porcelain, with 35-50% SiO2 reactive.
– artificial – fly ash, with over 25% SiO2 reactive;
The portland clinker: his hydraulic activity is influenced by:
– the chimico-mineralogical nature of the raw materials;
– composition, homogeneity and fineness of the raw mixture;
– the existance of the mineralizator;
– termotechnological regime of obtaining clinker

3.3. Stage III

Was obtained binders in the following systems:
– portland cement – reactive MgO;
– portland cement – reactive MgO – pozzolana;
– portland cement – calcar brucitic calcinat;
– portland cement – calcined brucitic limestone- pozzolana.

Binder masses were characterized from physical point of view (water of standard consistence, setting time and stability, according SR EN 196-3:1995), chemical (water chemical bounded, according to CEPROCIM method), mineralogical (diffraction of X radius) and mechanical (mechanical strengths at bending and compression up to 90 days). Chemical and mineralogical analysis were performed at different terms (2 hours, 5 hours, 2 days, 7 days, 28 days, 90 days) in order to observe mechanism of hydration-hardening.

The binder masses with above 20% MgO absorb CO2 from atmosphere by reason of the magnesiun hydroxide carbonatation process, present in the system.

3.4. Stage IV

• Was obtained the binder masses with the following characteristics:

– class of resistance 32,5R-42,5R, for the binders with 5% reactive MgO content
– class of resistance 32,5R, for the binders with 10% reactive MgO content

• In the portland cement – reactive MgO – pozzolana system:

– class of resistance 32,5R-42,5R, for the binders with 5% reactive MgO and 10% fly ash content
– class of resistance 32,5R, for the binders with 10% reactive MgO and 10% fly ash content

• In the portland cement – calcined brucitic limestone – pozzolana system

– class of resistance 32,5R, for the binders with 5% reactive MgO and 20% burnt brucite limestone content

• In the portland cement – calcined brucitic limestone – pozzolana system
  – class of resistance 32,5R, for the binders with 20% burnt brucite limestone and up to 10% pozzolana content
• SWOT analysis performed to obtain binder mass with 20 % calcined brucitic limestone (the portland cement- calcined brucitic limestone system) has highlighted the advantages of making it compared to a portland cement with addition:
  – fuel consumption reduced by cca.15%
  – energy consumption reduced by approx. 9%
  – CO2 emission decreases with approx. 20%
  – manufacturing price lower (considering the energy consumption)
  – organic binder is that the strengthening of the atmosphere absorbs a quantity of CO2
  – broadening the range of binders for construction materials.

3.5. Stage V

A patent application for the new types of ecological binders: “Portland Cement obtained from nonconventional raw materials”, OSIM registration numero A/00687/05.09.2008
Round Table to disseminate the knowledge

4. Dissemination of information:

• Noi sisteme liante ecologice continand MgO -The 5th National Conference “NEW RESEARCH TRENDS IN MATERIAL SCIENCE” – ARM-54 Sibiu, Romania 5-7 September 2007
• Sisteme liante cu continut de MgO multifunctionale -1st Conference “NANOSTRUCTURED MULTIFUNCTIONAL MATERIALS” – Sinaia, Romania 18-20 Octombrie 2007
• Novel construction binders – EUROPEAN CONGRESS ON ADVANCED MATERIALS AND PROCESSES, Nurnberg, Germania, 10-13 septembrie 2007
• New ecological binding systems containing magnesium oxide – INTERNATIONAL CONFERENCE ON STRUCTURAL ANALYSIS OF ADVANCED MATERIALS, Patras Grecia, 2-6 Septembrie 2007
• Complex technologies of brucitic limestone capitalization in environmental protection – XII BALKAN MINERAL CONGRESS, Delphi, Grecia, 10-14 iunie 2007
• Cercetari pentru realizarea unor noi sisteme liante ecologice pe baza de MgO cu proprietati absorbante de CO2 din atmosfera -Conferinta EXCELLENCE RESEARCH – A WAY TO E.R.A., Brasov, 24-26octombrie 2007.
• Investigations for obtaining new ecological binding systems based on MgO – XV International Conference, Mechanics of composite materials, 26-30 May, 2008, Riga, Latvia
• Cercetari pentru realizarea unor noi sisteme cimentoide cu continut ridicat de MgO – Conferinta EXCELLENCE RESEARCH – A WAY TO INNOVATION, Brasov, 27-29 iulie 2008.