WO2011089292A1

WO2011089292A1 - Capture and sequestration of co2 by means of the carbonatation of ceramic waste

Info

Publication number: WO2011089292A1
Application number: PCT/ES2011/000015
Authority: WO
Inventors: Emilio Galan Huertos; Patricia Aparicio Fernandez
Original assignee: Universidad De Sevilla
Priority date: 2010-01-25
Filing date: 2011-01-25
Publication date: 2011-07-28
Also published as: ES2364421B2; ES2364421A1

Abstract

The invention disclosed has as the objective thereof the capture and sequestration of CO₂ in ceramic materials proceeding from construction waste. Such materials react directly with CO₂ in the presence of water producing carbonates, such that the CO₂ is stabilised in a permanent manner. The present invention has dual environmental application: on the one hand, reduction in atmospheric CO₂ is produced by virtue of the injection thereof into ceramic construction waste and, on the other hand, reduction in the negative landscape impact caused by ceramic construction waste.

Description

Title

Capture and sequestration of C0 ₂ by carbonation of ceramic waste Object of the invention

The invention is aimed at capturing and sequestering C0 ₂ in ceramic materials from construction waste. These materials react directly with C0 ₂ in the presence of water producing carbonates, so that C0 ₂ is permanently stabilized.

The present invention has a double environmental application: on the one hand, there is a reduction in atmospheric C0 ₂ since it would be injected into ceramic waste from the construction and on the other, the negative landscape impact caused by the ceramic waste from the construction would be reduced .

State of the art

The use of fossil fuels widespread since the beginning of the Industrial Revolution (referring to the Northern Hemisphere above all), causes the release of approximately 7,000 million tons of coal into the atmosphere each year, in the form of carbon dioxide. This gas has also been generated as a side effect of deforestation and the concomitant destruction of soils, which releases the carbon retained in them temporarily in the form of organic matter. On the other hand, natural activities of the Planet, such as the emission of large amounts of gases by volcanism, contribute significantly to this increase in gases in the atmosphere. It is estimated that if the proportion of the C0 ₂ in the atmosphere doubling would increase of 2.5 ° C of the average temperature of the Earth.

The United Nations, through the Intergovernmental Panel on Climate Change, IPCC, considers in Report of Working Group 1, in the Fourth Assessment Report Climate Change 2007, that climate change is a reality with devastating consequences for Humanity , and it is argued as the main anthropogenic cause the influence of "greenhouse gases" (C0 ₂ , CH ₄ , NO _x , water vapor) in the atmosphere. The greenhouse effect of C0 ₂ is so important that it is estimated that if the proportion of C0 ₂ in the atmosphere is doubled it would mean an increase of 2.5 ° C in the average temperature of the Earth.

Given that the generation of these gases is linked to the development of countries, production and accumulation is increasing and their decrease is unlikely globally. The International Energy Agency (IPA) predicts an increase in the demand for primary energy until 2030. In electricity, demand is expected to double, requiring the installation of 5000 GWe of new power. C0 ₂ is the industrial gas mostly emitted in developed countries, due to the use of fossil fuels, which are the main energy generators. As indicated in the Third Evaluation Report (TIE) of the Intergovernmental Panel on Climate Change (IPCC) (Metz et al. 2005) "most of the results of the models indicate that the known technological options could allow to achieve very diverse levels of atmospheric C0 ₂ stabilization ", but that" no technological option alone can achieve the necessary emission reductions ". Rather, a combination of mitigation measures will be needed to achieve stabilization.

The capture and storage of C0 ₂ (CAC or CCS "carbon capture sequestration") is considered one of the options to reduce the emissions of C0 ₂ generated by human activities. Other technological options are the following: 1) the reduction of energy demand by increasing the efficiency of energy conversion and / or use devices; 2) the decarbonisation of the energy supply (opting for fuels with less carbon, for example, replacing coal with natural gas), and / or increasing the use of renewable energy sources and / or nuclear energy (which, in definitively, they emit scarce amounts, if any, of C0 ₂ ); 3) the sequestration of C0 ₂ through the improvement of natural sinks through biological fixation; and 4) the reduction of greenhouse gases other than C0 ₂ .

The CAC, or CCS (Carbon Capture and Storage) is probably the biggest geotechnological challenge of the 21st century. The CAC first involves the use of technologies to collect and concentrate the C0 ₂ produced in industrial sources, then transport it to an appropriate storage location and then store it isolating it from the atmosphere for a long period of time.

The possible storage methods that arise are the following:

a) Injection of C0 ₂ into the deep layers of the oceans. It has the disadvantage that the technology is immature and there are studies that indicate that it can affect marine ecosystems.

b) Mineral carbonation (in streamers). It has the disadvantage that it is a process of high energy costs, in addition to being too local at regional level. c) Geological storage. It has the disadvantage that there is a lack of knowledge of the storage potential of different types of rock. On the other hand, it has the advantages that the estimated retention time is hundreds to millions of years and the technology is directly applicable due to the experience in exploration and production of oil, gas, coal, waste injection and groundwater protection.

The types of geological formations and structures most conducive to the deep storage of C0 ₂ have been widely documented in the scientific and technical literature generated in recent years: 1) coal layers rich in methane, 2) depleted or depleted deposits of hydrocarbons (oil and gas), 3) deep saline aquifers, and 4) cavities in salt formations. The first three types are postulated as more prominent objectives, although their presence and storage capacity, that is, their dimensions, are conditioned by the specific geological features of each territory. Other possible formations or geological structures (such as basalts, bituminous slates and abandoned mines) represent storage options that have not yet been studied enough to be able to assess their potential today.

It is generally expected that the storage of C0 ₂ in hydrocarbon deposits or in deep saline aquifers will take place at depths below 800 m, where the pressure and temperature will result in the C0 ₂ being in a liquid or supercritical state . Under these conditions the density of C0 ₂ will range between 50 and 80% of the density of water, a percentage that approximates the density of certain crude oils, so that ascending forces originate that tend to drive C0 ₂ upwards . It is for this reason it is necessary that there is a rock seal on the reservoir rock for the C0 ₂ remains retained underground.

On the other hand, preliminary investigations by the inventors have shown that construction materials that contain calcium and / or magnesium in their composition can react with carbon dioxide to give rise to carbonates, thus constituting a possible alternative to mineral carbonation at from waste, as an alternative for the capture and storage of C0 ₂ (Coal Capture Sequestration, CCS).

It should be noted that in Spain 35 million tons of waste from construction and demolition (DRC) are produced every year, of which only one million are reused, while another 25 million are deposited in landfills not controlled. The environmental impact generated by the RDCs is well known because the vast majority are taken to landfills without any prior selection. Although RDCs are considered to be mostly inert or assimilable to inert and that do not pollute, they produce a great visual and landscape impact, due to the large volume they occupy and the poor environmental control exercised over the land chosen for deposit. .

The negative visual and landscape effect produced by DRCs is not only a consequence of poor management, but also that during the open-pit extraction of raw materials, which are used for the production of materials construction, there is a great visual impact. It should be noted that Article 13 of Royal Decree 105/2008 on the production and management of DRC (BOE 02/13/08), makes a special mention to the regulation of the use of DRC in restoration, conditioning or filling works, what can be considered as a valuation operation.

The purpose of this invention is to propose the injection of C0 ₂ into quarries and gravels recovered with RDC. For it is part of laboratory experiments on ceramic materials and C0 ₂ in different environmental conditions. It has been shown that in the presence of water carbonation process is a direct flow of C0 ₂ at low pressure (<20 bar). Experiences have been carried out with CC½ in a supercritical state and it has been proven that the carbonation process has a lower yield.

Description of the figures

Figure 1. X-ray diffraction diagrams showing the variation of the calcite content from the initial sample (black diagram), to the final sample (blue diagram) after 65 h of reaction with C0 ₂ in the presence of 10% water

Description of the invention

The present invention aims at capturing and sequestering C0 ₂ in ceramic materials from construction waste. In the presence of water, at varying pressures of C0 ₂ and depending on their initial mineralogical composition, these materials react directly with C0 ₂ producing carbonates, so that carbon dioxide is fixed permanently. The presence of water is essential for such a carbonation reaction to occur in ceramic materials, the proportion of water having to vary between 5 and 30% by weight depending on the composition and manufacturing temperature of the structural ceramics. These ceramic materials are manufactured from common clays in a temperature range of 800 ° C-1100 ° C.

For the capture of C0 _2, we start from ceramic construction residues that are being used for the recovery of quarries and gravels and that are characterized by containing calcium and magnesium at least in a proportion greater than 5%, mainly in the form of oxides and / or hydroxides.

These ceramic materials are injected with low pressure C0 ₂ (with an injection pressure of C0 ₂ varying between 0.5 and 80 bar, the highest yields at pressures of C0 ₂ <20 bar) with which it reacts chemically always in the presence of water giving rise to carbonates, so it is permanently fixed.

The reaction yield is higher at low pressures of C0 _2, so it is not necessary to reach large pressures of C0 ₂ and therefore, to store at 800m depth as required by other C0 ₂ capture alternatives

It is a process of direct carbonation of low cost, since it is not necessary to perform a classification and grinding of the material and therefore it is not necessary to consume energy to favor the process.

You can raise the capture of C0 ₂ directly from the chimneys of the ceramic industries, or any other that produces C0 ₂ emissions and lead it to the recovered quarries. In the first case the cost would be considerably reduced. In addition, the life cycle of common clays would be completed. Thus extracted clay used to produce structural ceramics stage during which C0 ₂ emissions occur, this gas is captured and inserted in quarries exploited when recovering waste bricks and other building materials.

Embodiment of the invention

A preferred and non-limiting embodiment of the invention is described below. The raw material is based on a mixture of common clays containing 30% carbonates (calcite and dolomite), 30% quartz, 37% phyllosilicates and 3% feldspars. This raw material is cooked at 850 ° C, the result being a ceramic product structural that contains 5% calcite, together with high temperature minerals and oxides of Ca and Mg.

A mixture of this ceramic product is prepared with water (10% by weight) and a current of 1 bar of C0 ₂ is applied at a temperature of 30 ° C for 65 hours.

After this process the content of calcite increases from 5% to more than 15% by weight, due to the carbonation produced after reacting the calcium present (obviously not in the form of calcite) with C0 ₂ in the presence of water.

To evaluate the variations of the calcite content, this reaction should be reproduced in an X-ray diffractometer equipped with a reaction chamber and a phase quantification procedure based on Rietveld refinement (for example TOPAS) be applied. In Figure 1 the first diagram corresponds to that of the original sample (in black). The following diagrams correspond to the products formed after adding water and injecting the current of C0 ₂ . Specifically, the pink diagram corresponds to a reaction time of 24 hours. The following were obtained every 1.5 hours, and so on until the total reaction time was 65 hours (blue diagram). The results of the quantitative analysis appear in Table 1.

Table 1.- Evolution of the calcite content in the presence of C0 ₂ as a function of the reaction time.

Claims

1. Capture and sequestration of C0 ₂ by carbonation of ceramic waste characterized in that it consists of the injection of C0 ₂ in ceramic waste from the construction at a variable pressure between 0.5 bar and 80 bar (preferably <20 bar), in presence of water between 5% and 30% by weight according to the composition, which must be greater than 5% in Ca and Mg and for the time necessary for all available Ca and Mg to be transformed into carbonates.

2. Capture and sequestration of C0 ₂ by carbonation of ceramic waste according to claim 1 characterized in that the ceramic waste has a composition in Ca and Mg of more than 5% by weight and the injection time of C0 ₂ will be necessary for all available Ca and Mg are transformed into carbonates.

3. Capture and sequestration of C0 ₂ in quarries and gravels rehabilitated or in recovery with ceramic waste according to the previous claims, characterized in that it constitutes an alternative of low economic cost, since it is not necessary to work with C0 ₂ in supercritical state or carry out storage at 800m of depth.