Abstract The paper presents the comparative study regarding the turbidity removal using aluminium sulphate Al2(SO4)3*18H2O and polyaluminum chlorides, Aln(OH)mCl3n-m, commercial name, Sachtoklarr 39, in water treatment plant from Covasna City. The parameters that influence the treatment process and the efficiency of turbidity removal were studied. The water characteristic parameters of Basca Mare and Covasna rivers - the two sources of water alimentation for Covasna water treatment plant were...
Autori: Daniela Simina Stefan, Cristina Costache, Viorica Ruxandu, Monica Balas, Mircea Stefan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25462

AbstractWashing black aluminum (Al) slag to obtain soluble salts is an important stage of the smelting slag treatment at technologicalprocess. This process is used to recover Al as a coagulant for water purification. This research aims at establishing the optimalconditions for washing (e.g. temperature (T), solid: liquid ratio (S : L), time, the recirculation waters in the system). The goal ofresearch was to determine: a) the removal with maximum efficiency of the soluble salts from black Al sla...
Autori: Romanita Teodorescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26243

AbstractThis paper continues the previous investigations regarding the technology for the Aluminum (Al) recovery as Al sulfate fromblack Al slag. Leaching is the next compulsory step in the Al extraction process. The paper studies the influence of mothersolutions´ (MS) recirculation resulted from the process within the system over the quality of Al sulfate and the siliceous residue(R) and, the aluminum nitride (AlN) hydrolyses in the leaching process. The optimum parameters determined are: *the ...
Autori: Romanita Teodorescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26250

Abstract Planktonic algal samples were collected from lakes with different salinity (Salt Lake Brăila, Amara Lake, Fundata Lake, Techirghiol Lake and Black Lake-Sovata), in which mud used in balneary therapy is formed. A total of 189 species were recorded: 35 Cyanobacteria, 10 Euglenophyceae, 96 Bacillariophyceae, 33 Chlorophyceae, 3 Chrysophyceae, 2 Cryptophyceae, 1 Xantophyceae and 9 Dinophyceae. The highest number of phytoplankton species was recorded in Techirghiol lake (127 species...
Autori: Liana Gheorghievici
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26719

Abstract The juglone (5-hydroxy-1,4-naphthalenedione) can be found in the leaves and fruits of the black walnut (Juglans nigra L.). This substance has an inhibitory effect on the growth of the vegetal species, phenomenon which is named allelopathy. The inhibitory effect of the 50-100% concentration of this water extract, prepared from the black walnut fruits, on the seeds germination, plantlets growth and peroxidasic activity – registered in the seedlings roots – was poor, compar...
Autori: Dorina Cachiţă-Cosma
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26730

The Amara Lake is located at the south-eastern part of Romania. It is a shallow lake with an average depth of 3m and average extent of 1.32 km2, having a particular importance for the area in which is situated. This importance derives from its main functions in the ecosystem, namely: source of food, shelter and breeding place for almost 54 bird, balneary tourism attraction and jobs for the residents of Amara who live in the northern part of the lake. Under these conditions, the sustainable devel...
Autori: Ofelia Axinte
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27282

These days many works analyse air pollution, sources of air pollution, the impact of air pollution on human health, and ways to reduce air pollution. Since air pollution is affected by many factors, this paper presents a multi-attribute decision-making approach to assess air pollution. The proposed approach comprises four steps: selecting the attributes for the assessment, applying the TOPSIS-F method (the Technique for Order of Preference by Similarity to Ideal Solution with fuzzy sets) in the ...
Autori: Edmundas Kazimieras Zavadskas
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27733

The efficiency of drainage installed in clay soils using ditch backfill of soil mixed with lime is presented in this paper. The drainage ditch backfill was mixed with lime where 0.6% of soil matter consists of active CaO. The paper proposes a methodology that determines an optimal amount of lime. The experimental site was set in Kalnujai, Raseiniai district, Lithuania. The measurement of filtration in drainage trench, the arable layer and the soil between drains was performed using a double r...
Autori: Mindaugas KlimaĹĄauskas
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28177