Banca de DEFESA: JORSIELE DAMASCENO CERQUEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : JORSIELE DAMASCENO CERQUEIRA
DATA : 24/04/2020
HORA: 14:00
LOCAL: Ambiente Virtual
TÍTULO:

OPTICAL DETECTOR FOR IDENTIFICATION OF WATER ADULTERATION IN AUTOMOTIVE NITROGEN LIQUID LIQUID REDUCING AGENT (ARLA 32)

PALAVRAS-CHAVES:

ARLA 32; Adulteration of ARLA 32; Infrared spectroscopy; Optical Detector

PÁGINAS: 100
GRANDE ÁREA: Outra
ÁREA: Robótica, Mecatrônica e Automação
RESUMO:

The Automotive Liquid Reducing Agent, known as ARLA 32 (aqueous solution containing 32.5% urea) is injected into the exhaust gas flow of Diesel vehicles that have Selective Reduction Catalyst (SCR) to reduce emissions of nitrogen oxides ( NOx). As a guarantee of effectiveness in reducing NOx and that the SCR is not deteriorated, it is essential to control the chemical composition of the ARLA. Adulteration of this compound by dilution in water has often been found, due to the high availability and low cost of the diluent element. This work proposes a new optical detector for in situ analysis of ARLA 32 adulterated with water in fuel stations, through spectroscopy in the near infrared. The preliminary tests carried out used a commercial LED in the near infrared (1050 nm, 1300 nm and 1450 nm) and a silicon photodetector, with a non-linear behavior of the transmitted radiation in relation to the water concentration. Thus, a dedicated spectrometer prototype was developed, using a wavelength of 1650 nm, in addition to the implementation of the InGaAs photodetector and a pulsating feeder circuit through a quartz crystal. A precision voltmeter with 0.1 mV resolution (display) was incorporated to read the measurements. Offset and sensitivity adjustment buttons were also implemented to calibrate the optical instrumentation. ARLA samples adulterated with specific percentages of water concentration were tested, showing the direct relationship of adulteration with the concentration of water in the sample and its molar absorptivity. Additional tests were carried out aiming at validating the equipment in the detection of adulterations. Thus, bulk ARLA samples collected from 5 different filling stations in the Metropolitan Region of Salvador were investigated for water adulteration. Urea values above 32.5% were found in all analyzed samples, which can be justified by the evaporation of demineralized water during storage. The results confirmed that the portable prototype developed for field measurement of ARLA samples at fuel stations, presents a quick analysis to identify and quantify the ARLA adulteration with water, and an affordable cost to provide diesel vehicle owners and inspection agencies with an innovative alternative for quality control of ARLA 32.

MEMBROS DA BANCA:
Externo à Instituição - DION BARBOSA DOS SANTOS RIBEIRO
Interno - 1194490 - IURI MUNIZ PEPE
Externo à Instituição - VALÉRIA LOUREIRO DA SILVA - Senai
Externo ao Programa - 1743075 - VITOR PINHEIRO FERREIRA