Sorption Enhanced Water Gas Shift for H2 production using sour gases as feedstock

Even though hydrogen is considered the future of energy carrier, it is still produced from fossil fuels therefore with no benefits for the CO2 emission reduction. This paper discusses an innovative concept for hydrogen production which combines the Acid Gas to Syngas (AG2S (TM)) concept and the Sorption Enhanced Water Gas Shift (SEWGS) process. The AG2S (TM) process produces H-2 and elemental Sulfur from H2S and CO2, then H-2 purification is performed through amine scrubbing. The SEWGS technology is a Pressure Swing Adsorption process where the CO2 and H2S are adsorbed on hydrotalcite-based material. With respect to amine scrubbing, SEWGS takes advantage of a higher operating temperature of 350 degrees C -400 degrees C which reduces temperature swing losses, lower regeneration energy and the possibility to recycle the H2S while capturing the CO2. This study aims at exploring the potential of the SEWGS technology by means of the evaluation of detailed mass and energy balances, showing the potentialities of the AG2S (TM)+SEWGS technologies which more than double the H-2 production efficiency (25.0%) with respect to the amine scrubbing configuration (10.7%). Including the steam production, the overall process efficiency can be higher than 90% which is again more than twice the value of the AG2S (TM) reference case. (C) 2019 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC

Mitigating Carbon Dioxide Impact of Industrial Steam Methane Reformers by Acid Gas to Syngas Technology: Technical and Environmental Feasibility

The aim of this work is to evaluate the potential application of a new sustainable technology, called Acid Gas to Syngas, on steam reforming process in order to reduce the carbon dioxide emissions. Indeed, steam reforming has high emissions of carbon dioxide, at almost 7 kg of carbon dioxide per 1 kg of hydrogen produced. The key idea of the new technology is to convert carbon dioxide and hydrogen sulfide coming from natural gas desulfurization into additional hydrogen. Coupling different software, i.e. Aspen HYSYS and MATLAB, a complete plant model, able to manage the recycle of unconverted acid gases, has been developed. The importance of introduced innovations is highlighted and a comparison between the old process and the new one with Acid Gas to Syngas technology is built up. With Acid Gas to Syngas technology the natural gas consumption and carbon dioxide emissions can be reduced up to 3%

Sulfur rich coal gasification and low impact methanol production

In recent times, the methanol was employed in numerous innovative applications and is a key compound widely used as a building block or intermediate for producing synthetic hydrocarbons, solvents, energy storage medium and fuel. It is a source of clean, sustainable energy that can be produced from traditional and renewable sources: natural gas, coal, biomass, landfill gas and power plant or industrial emissions. An innovative methanol production process from coal gasification is proposed in this work. A suitable comparison between the traditional coal to methanol process and the novel one is provided and deeply discussed. The most important features, with respect to the traditional ones, are the lower carbon dioxide emissions (about 0.3%) and the higher methanol production (about 0.5%) without any addition of primary sources. Moreover, it is demonstrated that a coal feed/fuel with a high sulfur content allows higher reductions of carbon dioxide emissions. The key idea is to convert hydrogen sulfide and carbon dioxide into syngas (a mixture of hydrogen and carbon monoxide) by means of a regenerative thermal reactor. This is the Acid Gas to Syngas technology, a completely new and effective route of processing acid gases. The main concept is to feed an optimal ratio of hydrogen sulphide and carbon monoxide and to preheat the inlet acid gas before the combustion. The reactor is simulated using a detailed kinetic scheme

Catalysts and Processes for H2S Conversion to Sulfur

Today, more stringent regulations on SOx emissions and growing environmental concerns have led to considerable attention on sulfur recovery from hydrogen sulfide (H2S). Hydrogen sulfide is commonly found in raw natural gas and biogas, even if a great amount is obtained through sweetening of sour natural gas and hydrodesulphurization of light hydrocarbons. It is highly toxic, extremely corrosive and flammable, and for these reasons, its elimination is necessary prior to emission in atmosphere. There are different technologies for the removal of H2S, the drawbacks of which are the high costs and limited H2S conversion efficiency. The main focus of this Special Issue will be on catalytic oxidation processes, but the issue is devoted to the development of catalysts able to maximize H2S conversion to sulfur minimizing SO2 formation, pursuing the goal of “zero SO2 emission”.This Special Issue is particularly devoted to the preparation of novel powdered/structured supported catalysts and their physical–chemical characterization, the study of the aspects concerning stability and reusability, as well as the phenomena that could underlie the deactivation of the catalyst.This Special Issue comprises seven articles, one communication, and one review regarding the desulfurization of sour gases and fuel oil, as well as the synthesis of novel adsorbents and catalysts for H2S abatement. In the following, a brief description of the papers included in this issue is provided to serve as an outline to encourage further reading