2022, Issue 68(72), Fasc. 1 (March)

Contents

pages 1- 8   Download

Syngas as a Viable Solution for Liquid Waste Capitalization

MARIA OANA AGAVRILOAIE, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania, agavriloaie.oana@gmail.com
MARIA HARJA, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania

pages 9 - 23   Download
Abstract
The use of finite resources for obtaining syngas and the accumulation of large amounts of liquid wastes give place to discussions and researches about new technologies and approaches to waste capitalization. Gasification is gaining attention as an efficient process for the conversion of waste. This paper highlights the advantages of using liquid waste as a feedstock for the gasification process. Syngas can be converted to numerous valuable chemical compounds, to olefins by Fischer-Tropsch synthesis in the presence of catalysts, to methanol or to dimethyl ether by direct synthesis and indirect synthesis by methanol dehydration in the same plant. Ammonia is another important chemical compound obtain from syngas. Hydrogen can be separated from hydrogen rich syngas and is a priced fuel of this days. The synthesis gas can be also utilized directly as fuel in the stationary engines of heavy equipment from manufacturing industries and for power plants or as a subsidiary for diesel fuels in transportation.
Keywords: liquid waste, syngas, gasification, fuel, clean energy.

The Impact of Climate Change on the Natural Reservation „Poiana cu Schit" from Iaşi County

CRISTINA CARMEN STINGU (PALICI), "Vasile Alecsandri" University of Bacău, Department of Environmental Engineering and Mechanical Engineering, Bacău, Romania, cristina.7422@yahoo.com
VALENTIN NEDEFF, "Vasile Alecsandri" University of Bacău, Department of Environmental Engineering and Mechanical Engineering, Bacău, Romania
ION SANDU, "Alexandru Ioan Cuza" University of Iaşi, Institute of Interdisciplinary Research, Department of Science, ARHEOINVEST Centre, Iaşi, Romania
VIORICA VASILACHE, "Alexandru Ioan Cuza" University of Iaşi, Institute of Interdisciplinary Research, Department of Science, ARHEOINVEST Centre, Iaşi, Romania
MIHAELA ORLANDA ANTONOVICI (MUNTEANU), "Alexandru Ioan Cuza" University of Iaşi, Faculty of Geography and Geology, Doctoral School of Geosciences, Iaşi, Romania

pages 25 - 41   Download
Abstract
The global climate change affects the future of our plant, due to the disastrous effects it produces. Romania is vulnerable against a series of natural and geological climate dangers, such as: floods, landslides, strong winds, droughts, extreme temperatures, as well as earthquakes which can cause numerous human and economic losses. The simulations that have been made using the global climate models indicate the fact that the main factors which determine this phenomenon are both natural (variations in the solar radiation and in the volcanic activity), and anthropogenic (changes in the composition of the atmosphere due to human activities). The cumulative effect of these two factors can explain the changes in the average global temperature we have been able to observe during the last 150 years. In order to diminish the damage produced by the climate change, we need to take prevention and safety measures. To do this, it is essential that we monitor the factors which determine these changes, that we evaluate the risks and that we establish measures in order to diminish the damage they might produce. Having these considerations in mind, our proposal is to monitor the natural and anthropogenic factors in the area surrounding the Poiana cu Schit natural reservation and to establish preventive and protection measures in order to keep this natural reservation unaltered.
Keywords: environmental factors, global temperature, protected areas.

Assessment of the Impact of Changes in the Combustion Process in a Brick-Making Plant which the Manufacturing Mix Changes

COSTEL ANTON, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania, costel.anton@gmail.com
SILVIA CURTEANU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania

pages 43 - 50   Download
Abstract
In this paper, the influence of the use of two auxiliary raw materials – sawdust and sunflower seed husks – on the oxygen consumption of the air brought in the process and the impact on the combustion products was analyzed on an industrial installation in real working conditions. It has been found that although in the case of recipes that use sunflower seed husks a smaller amount of gas with energy potential is released, it is preferable to use them because the amount of nitrogen oxides exhausted in the chimney of the furnace is lower.
Keywords: brick, waste added, reducing energy consumption, exhaust gases analysis.

Current Trends in the Recovery of Precious Metals from Electrical and Electronic Waste

NICOLAE APOSTOLESCU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
MIHAELA AURELIA VIZITIU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
CORINA CERNĂTESCU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
RAMONA ELENA TĂTARU-FĂRMUȘ, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
CLAUDIA COBZARU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
GABRIELA ANTOANETA APOSTOLESCU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania, ganto@ch.tuiasi.ro

pages 51 - 74   Download
Abstract
The recovery of precious metals can be efficiently done from waste. This method is considered a secondary source of raw materials, minimizing the need for exploitation and processing raw materials, while reducing energy and water consumption. Waste from electrical and electronic industry, used photographic film or waste from the jewelry manufacturing industry, fall into this category and lead to the recovery of approximately 25% of the annual requirement of gold and 20% of the annual requirement of silver. The paper presents the advantages of recycling waste containing precious metals, the difficulties of the recycling process and methods of recovering noble metals by processing electrical and electronic waste, focusing on technologies launched in recent years (bio-hydro-metallurgical processes, bio-oxidation static processes, adsorption on activated carbon or polymeric membranes, selective extraction).
Keywords: e-waste, gold and silver recovery, responsible recycling, recycling benefits.

Screening of the Amino Acid-Based Solvents for Carbon Dioxide Absorption

RAMONA ELENA TĂTARU-FĂRMUȘ, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
NICOLAE APOSTOLESCU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
CORINA CERNĂTESCU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
CLAUDIA COBZARU, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
MIHAELA POROCH, "Grigore T. Popa" University of Medicine and Pharmacy Iaşi, Faculty of Medicine, Department of Preventive Medicine and Interdisciplinarity, Iaşi, Romania, boanca.mihaela@umfiasi.ro

pages 75 - 89   Download
Abstract
Post-combustion separation and capture of CO2 from flue gases resulting from the burning of fossil fuels is a challenging technique due to the low pressure and low concentration of carbon dioxide, the impurities in the flue gases and the cost of regenerating the absorber. Researchers have developed various CO2 capture technologies such as absorption, adsorption, and membrane separation cryogenic technology. Of these, absorption was the most widely used. A wide variety of organic and inorganic substances have been proposed as solvents for CO2 uptake. But, these solvents have some major disadvantage such as: low absorption rate for K2CO3 solutions, high energy consumption for the amine solutions, high volatility and toxicity of ammonia. These can be solved by using another selective solvent for carbon dioxide. This paper provides information available in the literature on current solvents and the potential for amino acid salts to be used as absorbent for CO2 capture.
Keywords: acid gas, chemisorption, energy efficiency, equimolar blend, greenhouse gases.

Ex-Situ Remediation of a Petroleum Hydrocarbons Contaminated Soil

CARMEN ZAHARIA, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania, czah@ch.tuiasi.ro
MIRELA SIMION, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania
IRINA VOLF, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania

pages 91 - 106   Download
Abstract
The remediation of polluted soils is a key concern of modern society due to importance of this natural resource for present and its conservation for future. Intensive anthropic activities facilitate sometimes the discharge of wastes or hazardous pollutants (like petroleum hydrocarbons) that lead to the soil contamination. The aim of this research is to summarize the experimental data resulted in the assessment of the quality indicators for a hydrocarbon contaminated soil (at depth of 5 cm and 30 cm) as well as results from an ex-situ remediation technology at laboratory scale performed using extraction with organic solvents (carbon tetrachloride, glacial acetic acid and hexane) and repeated water washes. The wastewaters containing traces of pollutant were collected and also treated by adsorption (with pine sawdust as adsorbent) followed by sedimentation.
The proposed ex-situ remediation was found efficient (>79% petroleum hydrocarbons removal) if the amount of excavated contaminated soil is limited and the proposed working conditions could be applied.
Keywords: ex-situ remediation, chemical extraction, organic solvent, hydrocarbons, adsorption.