Energy and environmental assessment of hydrogen from biomass sources: Challenges and perspectives

Hydrogen is considered as one of the pillars of the European decarbonisation strategy, boosting a novel concept of the energy system in line with the EU's commitment to achieve clean energy transition and reach the European Green Deal carbon neutrality goals by 2050. Hydrogen from biomass sources can significantly contribute to integrate the renewable hydrogen supply through electrolysis at large-scale production. Specifically, it can cover the non-continuous production of green hydrogen coming from solar and wind energy, to offer an alternative solution to such industrial sectors necessitating of stable supply. Biomass-derived hydrogen can be produced either from thermochemical pathways (i.e., pyrolysis, liquefaction, and gasification) or from biological routes (i.e., direct or indirect-biophotolysis, biological water–gas shift reaction, photo- and dark-fermentation). The paper reviews several production pathways to produce hydrogen from biomass or biomass-derived sources (biogas, liquid bio-intermediates, sugars) and provides an exhaustive review of the most promising technologies towards commercialisation. While some pathways are still at low technology readiness level, others such as the steam bio-methane reforming and biomass gasification are ready for an immediate market uptake. The various production pathways are evaluated in terms of energy and environmental performances, highlighting the limits and barriers of the available LCA studies. The paper shows that hydrogen production technologies from biomass appears today to be an interesting option, almost ready to constitute a complementing option to electrolysis

Quantification of the carbon intensity of electricity produced and used in Europe

The EU has a comprehensive legislation to facilitate the energy transition towards a low carbon energy system and achieve the EU's Paris Agreement commitments for reducing greenhouse gas emissions. The European Green Deal is an integral part of the EU strategy for a sustainable and climate neutral economy by 2050. The decarbonisation of the power generation is essential to achieve the goal of decarbonising the energy and transport sectors. This paper presents a study conducted to quantify the carbon emissions associated to the production of electricity produced and used in European countries, based on a comprehensive methodology developed for this purpose. A spreadsheet model has been developed that considers the various sources for electricity generation, the type of plants, conversion efficiencies, upstream emissions and emissions from power plant construction, as well as the electricity trade. The results show the greenhouse gas emissions from the production and use of electricity in all European countries, revealing significant variations between countries. The carbon intensity of electricity shows a clear reduction trend since 1990, for most of the European countries. In the European Union, carbon intensity of electricity used at low voltage degreased from 641 gCO2eq/kWh in 1990 to 334 gCO2eq/kWh in 2019, and this trend is expected to continue in the coming years

Potential and limiting factors in the use of alternative fuels in the European maritime sector

The maritime sector is a key asset for the world economy, but its environmental impact represents a major concern. The sector is primarily supplied with Heavy Fuel Oil, which results in high pollutant emissions. The sector has set targets for deacrbonisation, and alternative fuels have been identified as a short-to medium-term option. The paper addresses the complexity related to the activities of the maritime industry, and discusses the possible contribution of alternative fuels. A sector segmentation is proposed to define the consumption of each sub-segment, so to compare it with the current alternative fuel availability at European level. The paper shows that costs and GHG savings are fundamental enablers for the uptake of alternative fuels, but other aspects are also crucial: technical maturity, safety regulation, expertise needed, etc. The demand for alternative fuels has to be supported by an existing, reliable infrastructure, and this is not yet the case for many solutions (i.e. electricity, hydrogen or methanol). Various options are already available for maritime sector, but the future mix of fuels used will depend on technology improvements, availability, costs and the real potential for GHG emissions reduction.(c) 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Renewable energy research progress in Mexico: a review

Mexico ranks 9th in the world in crude oil reserves, 4th in natural gas reserves in America and it is also highly rich in renewable energy sources (solar, wind, biomasss, hydropower and geothermal). However, the potential of this type of energy has not been fully exploited. Hydropower is the renewable energy source with the highest installed capacity within the country (11,603 MW), while geothermal power capacity (958 MW) makes Mexico to be ranked 4th in the use of this energy worldwide. Wind energy potential is concentrated in five different zones, mainly in the state of Oaxaca, and solar energy has a high potential due to Mexico's ideal location in the so called Solar Belt. Biomass energy has the highest potential (2635 to 3771 PJ/year) and has been the subject of the highest number of research publications in the country during the last 30 years (1982-2012). Universidad Nacional Autonoma de Mexico has led research publications in hydropower, wind, solar and biomass energy and Instituto de Investigaciones Electricas in geothermal energy during this period. According to the General Law for Climate Change the country has set the goal of generating 35% of its energy needs from renewable sources by 2024. This paper presents an overview of the renewable energy options available in Mexico, current status, main positive results to date and future potential. It also analyses barriers hindering improvements and proposes pertinent solutions. © 2014 The Authors

CORSIA Lower Carbon Aviation Fuels: An Assessment of the Greenhouse Gas Emission Reduction Potential

Curbing aviation emissions is clear goal for the aviation sector, but it is a challenging task. At international level, the ICAO CORSIA initiative promotes the use of alternative fuels as a means to decarbonise flights. Among alternative fuels, lower carbon aviation fuels (LCAF) have been proposed under CORSIA. LCAF refers to a fossil fuel, which have been produced in a way that results in at least 10% lower lifecycle GHG emissions compared to a benchmark value. This paper analyses potential LCAF solutions for reducing GHG emissions of kerosene production and evaluates them relative to the ICAO baseline of 89.0 gCO2eq/MJ of fuel. The study analyses the levers that can reduce GHG upstream emissions (emissions from crude oil production) and refining emissions as well. This study shows that no one lever can reduce emissions to a sufficient level to meet the requirement of being a CORSIA-eligible fuel, and therefore that the deployment of multiple levers needed. Since jet fuel comprises only around 10% of total refining output, the LCAF measures could support the implementation of large, high-abatement cost changes, such as refinery-wide carbon capture and storage that affects multiple fuels

Are algae ready to take off? GHG emission savings of algae-to-kerosene production

Aviation alternative fuels are perceived as an effective short-term mean to decarbonise our flights. Sustainable aviation fuels from algae have been recently approved for commercial flights, and here we present an assessment of their greenhouse gas (GHG) savings. Three case studies have been investigated with different plant designs and cultivation strategies. The Carbon Offsetting and Reduction Scheme for International Aviation's Life Cycle Assessment methodology is used as a guideline to assess the GHG saving potential of aviation fuels from algae. The approach here presented allows having a sound comparison with other alternative fuel production pathways. We show that the cultivation strategy based on oil maximisation does not necessarily provide significant advantages in terms of GHG savings. The assessed GHG savings fall in a wide range, being dependent on the inputs and cultivation strategy considered. In the best-case scenario, up to 68% of GHG savings can be achieved, therefore offering a substantial advantage over traditional fuels. When compared with the GHG saving of kerosene from other traditional bio-based feedstocks, like rapeseed, the results confirm algae as an interesting alternative, provided that certain conditions for their cultivation, such as high process optimisation, nutrient recycling and use of renewable energy to meet input demand, are met. The study also assessed the area potentially needed for an algae production plant able to supply large volumes of raw material to an existing commercial biorefinery. The findings confirm the potential of this feedstock to mitigate land abandonment on the coasts of the Mediterranean basin

Problems and Solutions Regarding the Centrifugal Casting of Wire Sheave for Heavy Cranes

The centrifugal casting of wire sheave is a technological method that ensures the important quality requirement, the continuity of the material in the active rolling zone of the sheave. However the centrifugal casting has some difficulties: the stability of the casting system, small productivity, gas permeability of the cast mould. The paper shows the problems induced by the centrifugal casting of these parts and the solutions for their solving

Современные взгляды на преждевременный разрыв амниотического мешка

Laboratorul Ştiinţific de Obstetrică şi Ginecologie, Institutul de Cercetări Ştiinţifice în Domeniul Ocrotirii Sănătăţii Mamei şi Copilului, Chişinău, Conferinţa Ştiinţifico-Practică „Medicina modernă, actualităţi şi perspective”, consacrată aniversării de 40 de ani ai Spitalului Clinic al Ministerului Sănătăţii, 27-28 mai, 2010, Chişinău, Republica MoldovaTraditionally, fetal membrane rupture was attributed to increased physical stress, which weakens the membranes. At the molecular level, premature rupture of the amniotic sac occurs as a result of collagen synthesis and alteration of the collagen structure in order to accelerate its degradation. In addition, these biochemical changes can be amplified by biophysical stress as well. The priorities of this research include elucidating the normal biological processes of fetal membranes, including extracellular matrix remodeling and apoptosis.Традиционно считается, что разрыв фетальных оболочек обусловлен увеличением физических нагрузок. На молекулярном уровне, преждевременный разрыв амниотического мешка происходит в результате нарушения синтеза коллагена, изменения структуры коллагена путем ускорения его деградации. Кроме того, биохимические изменения могут быть усилены биофизическим стрессом. Приоритеты этого исследования включают выяснение нормальный биологической активности плодных оболочек, в том числе ремоделирование внеклеточного матрикса и апоптоз

VATS anatomic pulmonary resections - first operations

IMSP SCR ,,Timofei Moșneaga”, Chișinău, Republica Moldova, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Tendința de bază în evoluția chirurgiei toracice în ultimii 20 ani constă în micșorarea traumei operatorii folosind diferite tehnici minim invasive (VATS) fără micșorarea calității și eficacității actului medical. Dezvoltarea chirurgiei VATS permite efectuarea intervențiilor în diferite patologii pleuro-pulmonare și mediastinale cu reabilitarea postoperatorie mult mai rapidă ceea ce permite începerea etapelor ulterioare în tratamentul combinat mult mai precoce. Material și metode: Prezentăm primele 3 cazuri de rezecție pulmonara anatomică (Lobectomie, Bilobectomie) efectuate în premieră în cadrul secției chirurgie toracică SCR ”Timofei Moșneaga”. Rezultate: Au fost efectuate 2 lobectomii și o bilobectomie inferioară VATS prin triplu-port, dublu-port și uniportal. Durata intervenției a fost în mediu 220 min. În 2 cazuri evoluția postoperatorie a decurs fără complicații, tubul de dren extras la a 3 zi și pacienții externați la a 6-a zi postoperator. Un caz (bilobectomie inferioara pe dreapta) a evoluat cu pierderi de aer prelungite. Tubul de dren fiind menținut până la 2 săptămîni. Concluzii: VATS este un progres clar în dezvoltarea chirurgiei toracice și ofera un avantaj real pacienților fără micșorarea calității și eficacității actului chirurgical.Introduction: The basic trend in the evolution of thoracic surgery over the last 20 years is the reduction of surgical trauma using different minimally invasive techniques (VATS) without reducing the quality and effectiveness of the medical act. The development of the VATS surgery allows interventions in various pleuro-pulmonary and mediastinal pathologies with a much faster postoperative rehabilitation which allows the start of subsequent stages in the combination therapy much earlier. Material and methods: We present the first 3 cases of anatomical pulmonary resection (Lobectomy, Bilobectomy) performed for the first time in the department of thoracic surgery of CRH "Timofei Mosneaga". Results: Two lobectomies and a lower VATS bilobectomy were performed by triple-port, double-port and uniportal. Average duration of the interventions was 220 minutes. In 2 cases the postoperative evolution was without complications, extraction of the drainage tube was at the 3rd day and patients discharged at 6th postoperative day. One case (lower right bileobectomy) evolved with prolonged air loss. The drainage tube was kept for up to 2 weeks. Conclusions: VATS is a clear breakthrough in the development of thoracic surgery and offers a real benefit to patients without reducing the quality and effectiveness of surgical intervention

Esofageal diverticulum: classical vs mini-invasive surgical approach

IMSP SCR ,,Timofei Moșneaga”, Chișinău, Republica Moldova, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Diverticulii esofagieni – patologie cu o incidență relativ rară atît in cadrul patologiei tubului digestiv,în general, dar și a esofagului,în particular. Acuzele mai frecvente sunt disfagia, eructațiile, sialorea (triada Leger) și manifestările pulmonare ale aspirației. Material și metode: Autorii analizează experiența Secției Chirurgie Toracică IMSP SCR ”Timofei Moșneaga” în tratamentul a 78 (anii 2000-2017) pacienți cu diverticuli esofagieni de diversă localizare. Examenul radiologic cu contrast și cel endoscopic sunt prioritare la stabilirea diagnosticului iar manometria esofagiană relevă tulburările de motilitate. Rezultate: Sunt prezentate aspectele principale ale tehnicii chirurgicale, complicațiile (17,88%) și mortalitatea (3,19%). Experiența diverticulectomiei videotoracoscopice cuprinde 11 cazuri cu evoluție postoperatorie necomplicată. Concluzii: O abordare minim invazivă trebue efectuată atunci când este posibil și necesita a fi adaptată la ficare pacient individual.Introduction: Esophageal diverticulum - disease with a relatively rare incidence in the pathology of the digestive tract, in general, but also in the esophagus, in particular. The most frequent symptoms are dysphagia, eructations, sialorrhoea (Leger triad) and pulmonary manifestations of aspiration. Material and methods: The authors analyze the experience of the Department of Thoracic Surgery, Republican Clinical Hospital ”Timofei Mosneaga”, in the treatment of 78 patients with esophageal diverticulum of diferent lacalization in the period 2000-2017 years. Radiological examination with contrast and endoscopy are the main methods in diagnosis of this pathology, but esophageal manometry reveals motility disorders. Results: The main aspects of surgical technique, complications (17.88%) and mortality (3.19%) are presented. The experience of videotoracoscopic diverticulectomy includes 11 cases with uncomplicated postoperative development. Conclusions: A minimally-invasive approach should be carried when possible and need to be adapted to patient individually