This report focuses on the feasibility of the power-to-ammonia concept. Power-to-ammonia uses produced excess renewable electricity to electrolyze water, and then to react the obtained hydrogen with nitrogen, which is obtained through air separation, to produce ammonia. This process may be used as a “balancing load” to consume excess electricity on the grid and maintain grid stability. The product, ammonia, plays the role of a chemical storage option for excess renewable energy. This excess energy in the form of ammonia can be stored for long periods of time using mature technologies and an existing global infrastructure, and can further be used either as a fuel or a chemical commodity. Ammonia has a higher energy density than hydrogen; it is easier to store and transport than hydrogen, and it is much easier to liquefy than methane, and offers an energy chain with low carbon emissions.The objective of this study is to analyze technical, institutional and economic aspects of power-to-ammonia and the usage of ammonia as a flexible energy carrier.
The COVID–19 pandemic led to local oxygen shortages worldwide. To gain a better understanding of oxygen consumption with different respiratory supportive therapies, we conducted an international multicenter observational study to determine the precise amount of oxygen consumption with high-flow nasal oxygen (HFNO) and with mechanical ventilation. A retrospective observational study was conducted in three intensive care units (ICUs) in the Netherlands and Spain. Patients were classified as HFNO patients or ventilated patients, according to the mode of oxygen supplementation with which a patient started. The primary endpoint was actual oxygen consumption; secondary endpoints were hourly and total oxygen consumption during the first two full calendar days. Of 275 patients, 147 started with HFNO and 128 with mechanical ventilation. Actual oxygen use was 4.9-fold higher in patients who started with HFNO than in patients who started with ventilation (median 14.2 [8.4–18.4] versus 2.9 [1.8–4.1] L/minute; mean difference 5 11.3 [95% CI 11.0–11.6] L/minute; P, 0.01). Hourly and total oxygen consumption were 4.8-fold (P, 0.01) and 4.8-fold (P, 0.01) higher. Actual oxygen consumption, hourly oxygen consumption, and total oxygen consumption are substantially higher in patients that start with HFNO compared with patients that start with mechanical ventilation. This information may help hospitals and ICUs predicting oxygen needs during high-demand periods and could guide decisions regarding the source of distribution of medical oxygen.
MULTIFILE
Arsenic contamination of groundwater is a major public health concern worldwide. The problem has been reported mainly in southern Asia and, especially, in Bangladesh. Slow-sand filters (SSF) augmented with iron were proven to be a simple, low-cost and decentralized technique for the treatment of arsenic-contaminated sources. In this research, three pilot-scale SSF (flowrate 6 L·h−1) were tested regarding their capability of removing arsenic from groundwater in conditions similar to those found in countries like Bangladesh (70 µg As(III) L−1, 26 °C). From the three, two filters were prepared with mixed media, i.e., sand mixed with corrosive iron matter (CIM filter) and iron-coated sand (ICS filter), and a third conventional SSF was used as a reference. The results obtained showed that the CIM filter could remove arsenic below the World Health Organization (WHO) guideline concentration of 10 µg·L−1, even for inlet concentrations above 150 µg·L−1. After 230 days of continuous operation the arsenic concentration in the effluent started increasing, indicating depletion or saturation of the CIM layer. The effluent arsenic concentration, however, never exceeded the Bangladeshi standard of 50 µg·L−1 throughout the whole duration of the experiments.
MULTIFILE
The ENCHANT project aims to clarify the differences between circular Calcium Carbonate (CCC) and grounded Calcium Carbonate (GCC), in order to expand the applications of the circular alternative CCC in the paint and coating industry. CCC is produced by pyrolysis from paper waste in an innovative process developed by the company Alucha Works B.V., and it can be applied again as filler or binder in consumer products (e.g. plastics, rubbers, paints and coatings) in a cost-effective manner. Products containing CCC have a higher content of circular resources, which minimizes their carbon footprint, and reduces the exploitation of primary resources. Performances of CCC in oil-based paints, however, is not optimal, due to a larger oil adsorption as compared to GCC. A physical and chemical characterization of CCC and GCC samples, including competitive oil-water adsorption measurements, would help Alucha to formulate a solution to match the properties of CCC and GCC, either adjusting the recycling process or applying a surface modification treatment to CCC. This would enable Alucha to expand the market for CCC, making oil-based formulation products more circular.
Sustainable energy production relies on smart design of functional nanomaterials with controllable sizes and structures. Core-shell nanoparticles are highly functional materials with properties arising from the core or shell materials or a combination of both. Changing the electronic properties of the shell by tailored design or induced by the underlying core lead to enhanced catalytic performances, especially in electrocatalysis. Tailoring the structure and functions of core and shell materials simultaneously often involves complex chemical methods. In this KIEM GoChem project, University of Amsterdam will work together with VSParticle, Spark904 and Inholland University of Applied Sciences to develop a novel and environmentally friendly method for the gas-phase synthesis of core-shell nanoparticles. A physical process will be used to control the growth and the mean size of the core whilst the structure and thickness of the shell will be tuned via selective adsorption and thermal processes. Core-shell nanoparticles produced by the proposed method can be directly incorporated into the next process step, e.g. at electrode surface or in (conductive) composites.