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In the present paper, we investigated CO 2 capture with six amine based absorbents, including three formulated solvents. Aqueous solutions of the amines (mass fraction; 30% for single amine and >30% for blended solvents) were used to evaluate the performance for CO 2 capture. Gas scrubbing, vapor-liquid equilibrium (VLE), and reaction calorimetry experiments were conducted in the laboratory to obtain the absorption rate, the amount of CO 2 absorbed, cyclic CO 2 capacity, and heat of reaction for each absorbent. The results of these absorbents were compared with the conventional amine absorbents (MEA, AMP, DEA, and MDEA). Three high performing formulated absorbents (RN-1, RN-2, and RN-3) were developed, and these had lower heats of reaction, higher cyclic capacities, and comparable absorption rates compared with MEA. Some blended solvents were already demonstrated with real blast furnace gas at pilot test plants with capacities of 1 ton-CO 2 /day and 30 ton-CO 2 /day and showed promising results in terms of reducing absorbent regeneration energy.

The iron and steel industry accounts for a considerable percentage of CO2 emissions from industrial sector and is a main application target for promoting the implementation of CCS (Carbon dioxide capture and storage) as a global warming countermeasure technology. RITE has conducted research and development (R&D) on chemical absorption that separates and recovers CO2 from blast furnace gas for more than 10 years, and has been successful in developing new absorbents with low energy consumption. This report presents the results obtained from RITE’s R&D activities.

COURSE50 (ultimate reduction of CO2 in the steelmaking process through innovative technology for Cool Earth 50) aims to capture, separate, and recover CO2 from blast furnace gas. From a practical realization viewpoint, three points are important. The first is energy consumption to regenerate the absorbent, second is the energy cost of the heat for regeneration, and third is the facility cost. The advantage afforded by the COURSE50 approach in relation to the CO2 capture process is the utilization of unused waste heat from the steel mills. Energy consumption to regenerate the absorbent is determined mainly by three factors: the regeneration reaction determined primarily by the structure of the chemical absorbent, the energy required to heat that volume of absorption liquid, which is affected by the absorption rate of the agent, and the heat loss from the processes. The most influential factor is the energy required for the regeneration reaction. We discovered high-performance absorbents with the advantages of high absorption rates, high cyclic capacities, and low heats of reaction, and we then compared these with monoethanolamine (MEA) and N-methyldiethanolamine (MDEA). The newly discovered absorbents performed well in terms of absorption rates and cyclic capacities. Among these absorbents, some showed lower heats of reaction than MDEA. These results provide a basic guideline for the discovery of potential amine-based absorbents that may lead to the development of new absorbent systems for CO2 capture.

Large-scale environmental problems have become prominent byproducts of the interactions between human activities and the biophysical settings in which they occur.

Earth observation has the potential to make significant contributions to policy and society, as we discussed in Chap. 1 of this book.

The result of a workshop bringing together an international advisory board of experts in science, satellite technologies, industry innovations, and public policy, this book addresses the current and future roles of satellite Earth observations in solving large-scale environmental problems. The book showcases the results of engaging distinct communities to enhance our ability to identify emerging problems and to administer international regimes created to solve them. It also reviews the work of the Policy and Earth Observation Innovation Cycle (PEOIC) project, an effort aimed at assessing the impact of satellite observations on environmental policy and to propose a mission going forward that would launch an “innovation cycle”. The achievements of such a mission would feed back to innovations in next-generation observation technology, thus contributing to global policy demand for policy-relevant information.

The Paris Agreement was adopted at UNFCCC COP21 in Paris, France in December 2015 as a new international framework for greenhouse gas reductions for the post-2020 period. It is a fair agreement applicable to all Parties. The Paris Agreement has a long-term objective of holding the increase in global temperatures to well below 2 ℃ above pre-industrial levels, and each Party shall communicate or update its Nationally Determined Contribution (NDC) every five years. Each party is to regularly provide information and to participate in expert reviews and a multilateral consideration of progress.

Earth observations can provide actionable science and information for policy through projections and forecasts; near real-time management or identification of deviations in long-term trends; and improved spatial, spectral, or temporal resolution (and better characterization of uncertainty) in data, observations, and models.

In the present paper, we investigated five synthetic amine based absorbents, including three formulated solvents. Aqueous solutions of the amines (mass fraction; 30% for single amine and >30% for blended solvents) were used to evaluate the performance for CO 2 capture. Gas scrubbing, vapor-liquid equilibrium (VLE), and reaction calorimetry experiments were conducted in the laboratory to obtain the absorption rate, the amount of CO 2 absorbed, cyclic CO 2 capacity, and heat of reaction for each absorbent. The results of these absorbents were compared with the conventional absorbent monoethanolamine (MEA). Three high performing synthetic absorbents (IPAE, IPAP and IBAE) were found, and these had lower heats of reaction, higher cyclic capacities, and comparable absorption rates compared with MEA. All formulated absorbents showed excellent cyclic CO 2 capacity and keeping moderately good absorption rate and lower heats of absorption. Some blended solvents were already demonstrated with real blast furnace gas at pilot test plants with capacities of 1 ton-CO 2 /day and 30 ton-CO 2 /day and showed promising results in terms of reducing absorbent regeneration energy.

In the present paper, we investigated CO2 capture with 24 tertiary amine absorbents, including three synthetic amines, with systematic modification of their chemical structures. Aqueous solutions of the amines (mass fraction 30%) were used to evaluate the performance for CO2 capture. Gas scrubbing, vapor–liquid equilibrium (VLE), and reaction calorimetry experiments were conducted in the laboratory to obtain the absorption rate, the amount of CO2 absorbed, cyclic CO2 capacity, and heat of reaction for each absorbent. The results for these absorbents were compared with the conventional tertiary absorbent N-methyldiethanolamine (MDEA). Seven of the investigated absorbents performed well with high absorption rates and cyclic capacities. Among these absorbents, some showed lower heats of reaction than MDEA. These results provide basic guidelines for discovery of potential tertiary amine-based absorbents that may lead to development of new absorbent systems in the CO2 capture area.

Ab initio calculations combined with the continuum solvation model have been conducted to obtain complete reaction pathways involved in the CO2 capture into monoethanol (MEA) aqueous solution. We have investigated the reaction pathways for the decomposition of MEA carbamate into bicarbonate. Although the already known pathways invoke a generation of free CO2(aq), we are concerned with another mechanism which does not involve such an intermediate. The neutral hydrolysis of the MEA carbamate was found to be a slow reaction that has an essentially two-step nature. We propose an alternative pathway that involves the carbamic acid as an intermediate that undergoes an alkaline hydrolysis leading to the formation of bicarbonate. Taking account of the novel reaction pathways elucidated here as well as the established routes for the formation of carbamate and bicarbonate may lead to a comprehensive understanding and a better prediction of the chemical CO2 capture process under specific conditions including pH (concentration of amine) and partial pressure of CO2.

In order to establish energy-saving technology for CO 2 capture from blast furnace gas, novel absorbents were developed in the laboratory and evaluated at a 1 t CO2 /d test plant. At first, CO 2 absorption and desorption behaviors of single-component amine solvents for simulated blast furnace gas (CO 2 /N 2 = 20%/80%) were investigated through a screening test using a small scrubbing bottle. These amine solvents were additionally analyzed using nuclear magnetic resonance ( 13 C NMR) spectroscopy and reaction calorimetry. The results of the laboratory experiments showed that there was a trade-off between absorption rate and enthalpy of absorption but some absorbents had unique features. For example, 2-isopropylaminoethanol (IPAE) had high absorption rate and small enthalpy of absorption. Then, new IPAE-based amine solvents (RITE solvents: RITE-A and RITE-B) were formulated and evaluated at the 1 t CO2 /d test plant. CO 2 regeneration energies of the RITE solvents were 3.3 and 3.1 GJ/t CO2 , respectively. With certain process conditions and plant specifications optimized, RITE-B was estimated to have the potential to achieve 2.5 GJ/t CO2 .

This work focuses on synthesizing and selecting hindered new amine absorbents to reduce the regeneration energy cost for CO2 capture. To achieve this target we synthesized seven secondary and two tertiary amine based CO2 absorbents with systematic modification of their chemical structures by an appropriate placement of substituent functional groups especially the alkyl functions (e.g. methyl, isopropyl, isobutyl, secondary butyl etc.), relative to the position of the amino group. Performances evaluations of these new absorbents in aqueous solutions were carried out based on their CO2 absorption rate, absorption capacity and heat of reaction measurements. Particular attention was paid to absorbents with a potential for high absorption rate and low heats of reaction. The results for the synthesized amino alcohols were then compared with conventional absorbents AMP and MDEA which were chosen as the base case for all comparisons. We found three high performance absorbents with advantages of high absorption rate and low heats of reaction compared with AMP and MDEA. Absorbents higher CO2 absorption rate and lower heat energy consumption characteristics will reduce the regeneration energy cost of CO2 during stripping.

There has been increased interest in the development of innovative carbon dioxide (CO2) capture and storage (CCS) applicable to the integrated coal gasification combined cycle (IGCC) equipped with a water−gas shift reaction, to reduce greenhouse gas emissions to almost zero (IGCC-CCS). We studied the heats of reaction (ΔHr) and vapor−liquid equilibria for N-methyldiethanolamine and novel absorbents [1,2-dimethylimidazole, 2-methylimidazole, 1-methylimidazole, imidazole, and 4-(2-hydroxyethyl)morpholine] obtained by the pKa-based screening method in our previous work and found a proportional relationship between pKa and ΔHr values. This allows estimation of ΔHr values by measuring their pKa. Measurements of vapor−liquid equilibria of novel absorbents provided important information on the CO2 capacity per absorption/recovery cycle. 1,2-Dimethylimidazole and 4-(2-hydroxyethyl)morpholine would be nominated as candidates suitable to absorb/recover CO2 with partial pressures at 1.6 MPa or higher without loss of...

Carbon dioxide (CO2) capture and storage (CCS) technology has emerged and become a promising tool for the control of greenhouse gas emissions. CCS is applicable to the integrated coal gasification combined cycle (IGCC) equipped with a water-gas shift reaction (IGCC−CCS). In our previous studies, we obtained novel chemical absorbents suitable for IGCC−CCS and examined vapor−liquid equilibria of the absorbents. However, the mechanisms of dissolution of pressurized CO2 into the solvents (e.g., determination of the fractions of CO2 absorbed chemically and physically under high CO2 pressure conditions) were not clear, even though this information is very important for estimation of the energy requirements for the CCS process. We examined the usefulness of 13C NMR spectroscopy to determine CO2 solubility and the components of inorganic carbon species (bicarbonate/carbonate and molecular CO2) in six different amine-containing aqueous solvents, at temperatures ranging from 40 to 70 °C and CO2 pressures ranging fr...

The COCS (Cost Saving CO2 Capture System) Project is concerned with the R&D of CO2 capture from gas streams using a chemical absorption process and has been conducted since 2004 as a five year project. Three high performance absorbents (Solvents A, B and C) with different characteristics have been developed to date in this project. The best energy performance as estimated by mathematical analysis was 2.57 GJ/t- CO2 in terms of regeneration energy. This value is far lower than the value for the commercially used absorbent (monoethanolamine, MEA; 4.0 GJ/t- CO2). These values were found in bench-scale tests (MEA: 4.1, Solvent-C: 2.8 GJ/t- CO2). If these new absorbents could be applied to CO2 capture the cost can be reduced by 40%.

The managerial model of treaty compliance theory suggests that the flow of information in the United Nations Convention on Climate Change/Kyoto Protocol regime is designed in two ways: monitoring environmental conditions (systematic observation) and monitoring compliance (self-reporting and review). The significance of satellite Earth observation is that it provides an integral part of systematic observation, although not directly responding to procedural treaty obligations such as report and review. If we are to use satellite data as a potential global common measurement tool, there is a need to bridge the gaps between observation methods and the policy framework.

A case of gastrointestinal cancer-associated antigen (CA19-9)-positive bronchioloalveolar carcinoma accompanied by bronchorrhea and respiratory failure successfully treated with corticosteroids is reported. The patient was treated with pulse methylprednisolone at a dose of 1,000 mg/day for three days, followed by oral prednisolone (60 mg/day). Within 2 days, the sputum volume decreased from >100 ml/day to 20 ml/day and it was finally controlled to 0-10 ml/day. The reduction in the sputum volume was associated with alleviation of dyspnea and hypoxemia. The levels of CA19-9 in the serum and the sputum were extremely high and an immunocytochemical study showed that the tumor cells were stained by CA19-9 antibody. This case demonstrates the therapeutic value of corticosteroids in the treatment of bronchorrhea in subjects with bronchioloalveolar carcinoma.

目的:腺房細胞癌のgrowth pattern別の細胞像について述べた.方法:組織診の確定した4つのgrowth patternについて細胞像を検討した.成績:1) Solid pattern: ライトグリーンに淡染する泡沫状, 顆粒状の広い細胞質を有する細胞が, 集塊状あるいは単離細胞として認められる. 核は小型円形で) 大小不同や核形不整はみられない. 小型核小体もみられるが, クロマチン増量は軽度である.2) Microcystic pattern: 細胞の少ない空胞状の構造として認識される. 細胞の形態は腺房様で, 核の異型は乏しい.3) Papillary-cystic pattern: 乳頭状の集塊が主体で, 単離細胞は少ない. 集塊の辺縁には腺房様構造が観察される. 2) および3) では砂粒体やvacuolated cellがみられる.4) Follicular pattern: 甲状腺濾胞に似た構造がみられ, 腔内には好酸性の物質がみられる.結論:papillary-cystic patternを除いてgrowth patternと予後や臨床態度との相関関係はみられないといわれている. しかし) 4つのgrowth patternにみられる腺房様構造, 乳頭状構造, vacuolated cell) 砂粒体は腺房細胞癌の細胞診断において重要である.

Ab initio molecular orbital calculations combined with the polarizable continuum model (PCM) formalism have been carried out for a comprehensive understanding of the mechanism of carbon dioxide (CO2) absorption by aqueous amine solutions. CO2 is captured by amines to generate carbamates and bicarbonate. We have examined the direct interconversion pathways of these two species (collectively represented by a reversible hydrolysis of carbamate) with the prototypical amine, monoethanolamine (MEA). We evaluate both a concerted and a stepwise mechanism for the neutral hydrolysis of MEA carbamate. Large activation energies (ca. 36 kcal/mol) and lack of increase in catalytic efficiency with the inclusion of additional water molecules are predicted in both the mechanisms. We also examined the mechanism of alkaline hydrolysis of MEA carbamate at high concentrations of amine (high pH). The addition of OH(-) ion to carbamate anion was theoretically not allowed due to the reduction in the nucleophilicity of the former as a result of microsolvation. We propose an alternative pathway for hydrolysis: a proton transfer from protonated MEA to carbamate to generate the carbamic acid that initially undergoes a nucleophilic addition of OH(-) and subsequent low-barrier reactions leading to the formation of bicarbonate and free MEA. On the basis of the calculated activation energies, this pathway would be the most efficient route for the direct interconversion of carbamate and bicarbonate without the intermediacy of the free CO2, while the actual contributions will be dependent on the concentrations of protonated MEA and OH(-) ions.

To elucidate the morphological feature of portal hypertensive colopathy (PHC), the macroscopic and microscopic vascular alterations of colonic mucosa was observed in rats with thioacetamide-induced liver cirrhosis. The colored latex was injected into the portal vein and filled the peripheral veins on the colonic mucosa. Histologic study revealed an increased in the number of the cross sections of venous vessels containing the colored lactices in the lamina propria mucosa(LP), lamina submucosal(SM) and muscularis propria(MP) in the cirrhotic rats. Stereoscopic results of the vascular cast obtained from the cirrhotic rats showed the presence of two characteristic vascular sings, i.e., winding and tree like dilated vessels (WT) and vascular ectasia (VE). WT was characterized by tortuosity, dilatation and increase of the venous vessels in the LP, SM and MP, and VE was vascular spider-like lesion mainly in the LP or a clump of tortuous vessels in LP, SM and MP. In the clinical study, 38 patients with liver cirrhosis and 40 normal control received colonoscopic examinations. The vascular lesions similar to WT and VE were seen in 78.9% and 65.8% of cirrhotic patients, compared to 10.0% and 7.5% in the control. The differences were statistically significant indicated that WT and VE were thought to be the typical experimental models of PHC. Since the cirrhotic rats used the present study were administered thioacetamide for only 12 weeks, it was suggested that PHC could occurred even in early stage of liver cirrhosis with mild portal hypertension. Neither WT nor VE were associated with the Child-Pugh's grade of cirrhosis.

We describe an acid dissociation constant (pKa)-based screening of chemical absorbents to treat a gas stream containing carbon dioxide (CO2) in a wide range of partial pressures (0.1–4 MPa). The so...

In the framework of the COCS (Cost Saving CO 2 Capture System) project we continue to develop high performance CO 2 absorbents to reduce the regeneration energy cost to almost half the current cost. To achieve this target we investigated twenty five tertiary amine based CO 2 absorbents with different chemical structures. Solvent selection procedures were carried out based on their CO 2 absorption rate, loading capacity and heat of reaction measurements. We found several high performance absorbents with advantages of high absorption rate and low heats of reaction compared to MDEA.