Volume 23, No. 3 (2017)

LABORATORY APPLICATIONS IN WASTEWATER TREATMENT BY USING FLOCCULATION PROCESS

NARCIS BARSAN(*1), MARIANA TURCU(2), VALENTIN NEDEFF(1,3), EMILIAN MOSNEGUTU(1), DANA CHITIMUS(1)

In the application of coagulation and flocculation process in the wastewater treatment, the laboratory activities are very important and sometime even indispensable. These activities provides some solutions to the efficiency that can be obtained and offer the possibly of results extrapolation to the industrial applications. The present study attempted to verify some possible laboratory application of the Acefloc organic flocculants series to the municipal waste leachate treatment. In these sense, some laboratory techniques were implemented to evaluate de flocculants efficiency by analyzing some quality parameters. In the case of Acefloc 00303L flocculants use were obtained the best performances regarding the analyzed quality indicators reduction. By using the flocculation process, the COD concentration decrease with 85.35 % in the case of Acefloc 00303L flocculants use

MODELING AND OPTIMIZATION OF BAKERY YEAST (SACCHAROMYCES CEREVISIAE) VIABILITY BY USING EXPERIMENTAL DESIGN PROCEDURE

ANA-MARIA GEORGESCU(1), DUMITRA RADUCANU(1*)

This paper presents the application of kn experiment design procedure for simulation and optimization of growth capacity for baker’s yeast, Saccharomyces cerevisiae. There were performed 27 experiments according to the experimental design procedure. The input variables were: the amount of carbohydrates (X1), temperature (X2) and pH (X3) and the output variable was the autolyzed cells (Y). The optimal conditions for growth parameters of Saccharomyces cerevisiae were obtained for an amount of carbohydrates (glucose) of 46.8 g·L-1, a temperature of 30oC and a pH of 5.7.

ORIENTATION SYSTEM OF PV PANELS AFTER SUN

GEORGE EDUARD HOLMAN(*1), CIPRIAN AFANASOV(1)

The purpose of the project is create a PV panels orientation system after the sun, with return to home position when dark is coming. The system must be energetically autonomous, and also have the ability to constantly provide power. The orientation of photovoltaic panels is an important factor that we must take into account in the design of energy production systems based on solar radiation. Solar guidance systems increase the efficiency of the power generation system by keeping the panels in a position perpendicular to the light rays. The two-axis orientation method was used. The wiring diagram has been designed so that the guidance system works in both manual and automatic modes. For the system to be energy-independent and, linked to the power supply of the drive motors for the two axis, we used a MPPT charger for the battery used as a energy source. Finding the best solutions for increasing system efficiency and energy independence will be presented in this paper.

NEW TRANSITION METAL OXALATO COMPLEXES WITH DABCOH22+ AS ADVERSE CATION: SYNTHESIS AND INFRARED STUDY

MAMADOU NDIAYE(1), ABDOULAYE SAMB(1), LIBASSE DIOP(*2)

On allowing DABCOH2(HC2O4)2 to react with transition metal dihalides in ethanol, a new series of complexes of general formula M(oxalate)2 DABCOH22+. nDABCOH22+.2X- (n=1/2;1) have been obtained. When (n=1) a dimeric structure is suggested, the two monomeric species being hold together by biprotonated DABCO through N-H…O hydrogen bonds. In the case of the complex M(oxalate)2DABCOH22+ .1/2 DABCOH22+.2X- -M = Ni, Cu- the structure is an infinite chain. The environment around the metallic centers is octahedral or square pyramidal. The oxalate behaves as a monochelating and hydrogen bonds involved ligand or is only concerned by hydrogen bonds.

NEW ZINC OXALATO AND HYDROGENOXALATO COMPLEXES: SYNTHESIS AND INFRARED STUDY

GORGUI AWA SECK(1), LIBASSE DIOP(1*), ABOUBACRY SENE(1)

Five new oxalato and hydrogenoxalato complexes with ZnBr2 have been synthesized and studied by infrared. Discrete structures have been suggested in the basis of spectroscopic data. The environments around the zinc centre being trigonal bipyramidal, tetrahedral, octahedral or monocapped octahedral. The anions behave as monochelating ligands. When the cations and OH group are involved in extra hydrogen bonds, a supramolecular architecture may be obtained.

THE MODELING OF GRAPHICAL AND ANALYTICAL DRYING PROCESS PARAMETERS RELATIONS IN CO2 ENVIRONMENT

NATALIA TISLINSCAIA(1), MIRCEA BERNIC(1*) , ANDREI LUPASCO(1), VLADIMIR ZAVIALOV(2), MIHAIL MELENCIUC(1), IANA TISLINSCAIA(1)

The engineering calculation of such dryer could be approximately done using Id-diagrams. There is such a diagram for air based dryers graphical and analytical calculation. The use of this diagram for CO2 modified environment is impossible; because it shows the thermo-physical characteristics for air which significantly differs from those of CO2. We made a tentative of modeling and calculate all the necessary parameters based on which there was created an Id-diagram for CO2 modified environment. Obtained graphical relations for temperature, enthalpy, moisture content and partial pressure will allow one to use them for CO2 modified environment based dryers.