Multi Absorber Research Articles

A pilot study comparing MEA and AEEA solvents in carbon capture

The goal of reducing the energy consumption of the CO2 removal process from flue gas may be pursued by modifying the process flow system, insertion of new technical solutions or developing new solvents. This paper provides data and discussion of the pilot plant experimental results using an aqueous 2-(2-aminoethylamino)ethanol (AEEA) compared to ethanolamine (MEA) solution. The post-combustion carbon capture pilot plant study was conducted with stripper inter-heating for advanced various flow systems, mainly for multi absorber feed (MAF) process setups, namely one with the lean amine stream being split 50/50 and served at different heights of the absorption column. A comparison with the standard (S) and split flow (SF) process flow modification has been also performed. The test showed that unskillful running of the process with AEEA solution can lead to excessive heat consumption, higher than for MEA.

Technical Assessment of Post-Combustion Carbon Capture using MEA through Process Modifications (Multi Absorber Feed and Inter-heating Stripper) for Large Scale Combined Cycle Gas Turbine Power Plant

Technical Assessment of Post-Combustion Carbon Capture using MEA through Process Modifications (Multi Absorber Feed and Inter-heating Stripper) for Large Scale Combined Cycle Gas Turbine Power Plant

Multi absorber made from rice husk and CaCl2-KMnO4 in absorbing water vapor and ethylene

The excessive ethylene gas and water vapor are not desired particularly in the fruit post-harvest handling, since the substances can shorten the shelf life and accelerate the rooting of the fruits thus its presence in the fruit handing is needed to be control. In this research, a multi absorber has been manufactured from calcium chloride (CaCl2) and potassium permanganate (KMnO4) with active rice husk as a matrix. The purpose of this study is to observe the capability of multi absorber of CaCl2 and KMnO4 trapped into rice hush matrix in absorbing water vapor and ethylene. In this study, CaCl2 and KMnO4 solutions with mol ratio of 1 : 2; 2 : 1; 1 : 3 and control (with CaCl2(1 mol) or KMnO4(1 mol)) were impregnated into the matrix. The experiment resulted that the ratio of CaCl2 (1 mol): KMnO4 (3mol) was able to absorb KMnO4 as much as 0.89 mg ethylene per 3 g absorber for 1 h of exposure. It also worked for absorbing water vapor as much as 1.03 g/g absorber for 7 days of storage at RH97%. Based on this experiment, the multi absorber resulted from this research is potential to be applied as ethylene and water vapor absorber.

Experimental results of advanced technological modifications for a CO2 capture process using amine scrubbing

This paper provides a discussion of the experimental results obtained at the amine-based carbon capture pilot plant having the capacity of 200 m3n/h of flue gas, using 30 wt% ethanolamine solution as a solvent. The objective was to prove the superiority of application of advanced amine flow systems as well as of the novel stripper internal heater fulfilling pilot Technology Readiness Level. Standard process flow sheet, multi absorber feed and split-flow process modifications with and without stripper interheating were examined. A vast number of process parameters were recorded during the trials. The data were critically analysed, compared and presented in the paper. Demonstrated process flow modifications resulted in a reduction of the reboiler heat duty by about 5%, while using internal stripper interheatingby 9÷11 %, comparing to standard amine-based carbon capture plant.

Design Considerations of Efficient Photo-Electrosynthetic Cells and its Realization Using Buried Junction Si Thin Film Multi Absorber Cells

AbstractAs is obvious from previous work on semiconductor photoelectrochemistry, single junction semiconductors do not provide either the required maximum photovoltage or a high photocurrent for solar water splitting, which is required for efficient stand-alone devices. From these experiences we conclude, that multi-junction devices must be developed for bias-free water splitting. In this article we present our design considerations needed for the development of efficient photo-electro-synthetic cells, which have guided us during the DFG priority program 1613. At first, we discuss the fundamental requirements, which must be fulfilled to lead to effective solar water splitting devices. Buried junction and photoelectrochemical arrangements are compared. It will become clear, that the photovoltaic (PV) and electrochemical (EC) components can be optimized separately, but that maximized conversion efficiencies need photovoltages produced in the photovoltaic part of the device, which are adapted to the electrochemical performance of the electrolyzer components without energetic losses in their coupling across the involved interfaces. Therefore, in part 2 we will present the needs to develop appropriate interface engineering layers for proper chemical and electronic surface passivation. In addition, highly efficient electrocatalysts, either for the hydrogen or oxygen evolution reaction (HER, OER), must be adjusted in their energetic coupling to the semiconductor band edges and to the redox potentials in the electrolyte with minimized losses in the chemical potentials. The third part of our paper describes at first the demands and achievements on developing multijunction thin-film silicon solar cells. With different arrangements of silicon stacks a wide range of photovoltages and photocurrents can be provided. These solar cells are applied as photocathodes in integrated directly coupled PV-EC devices. For this purpose thin Pt and Ni catalyst layers are used on top of the solar cells for the HER and a wire connected RuO2counter electrode is used for the OER. Electrochemical stability has been successfully tested for up to 10,000 s in 0.1 M KOH. Furthermore, we will illustrate our experimental results on interface engineering strategies using TiO2as buffer layer and Pt nanostructures as HER catalyst. Based on the obtained results the observed improvements, but also the still given limitations, can be related to clearly identified non-idealities in surface engineering either related to recombination losses at the semiconductor surface reducing photocurrents or due to not properly-aligned energy states leading to potential losses across the interfaces.

Gas leak due to a damaged GE Disposable Multi Absorber Canister used with an EZchange Module following its reinstallation during anesthesia

Gas leak due to a damaged GE Disposable Multi Absorber Canister used with an EZchange Module following its reinstallation during anesthesia

Massive gas leak following misconnection of a Datex-Ohmeda Multi Absorber Disposable canister

Massive gas leak following misconnection of a Datex-Ohmeda Multi Absorber Disposable canister

Unusual Cause of Leak in Datex Aisys

To the Editor: We wish to report a serious incident encountered while using the Aisys Carestation (Datex-Ohmeda, GE Health Care, Finland, through GE India). While delivering anesthesia to a young male undergoing craniotomy, we noticed that the soda lime exhausted. The Aisys Reusable Multi Absorber canister was removed, refilled with fresh soda lime, and then replaced on the Carestation. The water trap was also drained at this time. After replacement of the canister on the Carestation, a large leak was noted in the circle breathing system. The canister was removed and refitted, but the leak persisted and it was impossible to ventilate the patient’s lungs manually or in ventilator mode, even with a high fresh gas flow. Changing the breathing system to a Bain coaxial circuit connected to the alternate common gas outlet of the Aisys eliminated the leak and allowed ventilation of the patient’s lungs. A subsequent thorough examination of the Carestation revealed a soda lime granule trapped in the flap valve of the water trap, rendering that valve incompetent (Fig. 1). Removal of the granule eliminated the leak when the Carestation was checked out with a circle system. It is unclear how the soda lime granule reached the drain valve of the water trap. One possible explanation is that some brands of soda lime have a high content of dust and flowing gas may have carried that dust through the breathing system, leading to deposits caking in the condenser reservoir. Despite following the manufacturer’s instructions for refilling absorber canisters and in particular replacing the filters, we have noticed clogged dust collecting in the condenser reservoir. Choosing a brand of soda lime with low dust content may prevent this mishap.Figure 1.: (a) Water trap of Aisys with granule stuck in rubber flap valve; (b) canister with water trap.As the anesthesia workstation evolves, it becomes more complicated and less intuitive for the user attempting to troubleshoot a malfunction. The circle breathing systems on many of the new anesthesia workstations have become more complex, and some of the components may be hidden or at least not obvious. The condenser and water trap are integral components of the Aisys circle system. Education and in service training when using a new anesthesia workstation will enable early recognition of system failure. Prashant Kummar, MD Grace Korula, MD, DA Sathish Kumar, MD, DA P. A. Saravanan, MD, DA Christian Medical College and Hospital Vellore, Tamil Nadu, India [email protected]

Multi absorber stand alone liquid desiccant air-conditioning systems for higher performance

Achieving comfortable environment with the use of renewable energy or waste heat without creating the hazardous effects over the earth atmosphere are major challenges in the field of air-conditioning. Liquid desiccant technology is a promising option. For the past few decades research is going on worldwide to commercialize such systems. Hybrid liquid desiccant systems (combination of vapor compression (V-C) and liquid desiccant system) have got more attention probably due to higher COPs and lower regeneration temperature for such systems. In the present communication the steady-state performance of stand alone liquid desiccant systems has been simulated and analyzed. Falling film designs of absorber and regenerator have been selected for the study due to their lower pressure drops. The simulation of these components has been carried out by solving the basic mass and energy balance equations. These are nonlinear coupled first order differential equations, which have been solved by using fourth order finite difference Runge–Kutta method. The overall system has been simulated using Warner’s technique. Two new stand alone liquid desiccant cycles utilizing the potential of desiccant fully through multiple absorbers have been proposed. The proposed new cycles improve the COP of stand alone systems significantly. A parametric study has also been carried out on these liquid desiccant cycles to identify the key design parameters affecting the performance of the system.