Banca de DEFESA: MAELSON MENDONCA DE SOUZA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : MAELSON MENDONCA DE SOUZA
DATA : 30/10/2019
HORA: 10:00
LOCAL: Auditório do CT
TÍTULO:

DEVELOPMENT OF LIGHTWEIGHT AGGREGATES FROM
SCHEELITE WASTE, SEWAGE SLUDGE AND RICE HUSK ASH


PALAVRAS-CHAVES:

Lightweight aggregate; Scheelite residue; Sewage sludge; Rice husk ash;

reuse.


PÁGINAS: 132
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Civil
RESUMO:

The use of lightweight aggregates (LWAs) is a consolidated practice in
the construction industry. Its characteristics are relevant to various
engineering services. However, commercial manufacture of this product
is still quite limited. Brazil, for example, has only one LWA factory.
Over the years, the use of expandable clays has been supporting national
production; however, the gradual scarcity of natural resources requires
the use of more sustainable practices. Thus, this research aims to develop
LWAs suitable for use in engineering works and services, from the reuse
of scheelite residue (RPS), sewage sludge (SS), and rice husk ash (RHA).
Recent studies have shown that the production of these three wastes is

increasing in several countries. However, in opposition to this scenario,
the control agencies have been increasing the strictness of environmental
laws, making various traditional methods of disposal unfeasible. Thus,
this research can help in the preservation of natural resources and in
reducing the environmental impacts caused by such residues. It is also
intended to establish comparative analysis between manufactured and
commercially available LWAs, and to evaluate the effects of sintering
temperature and raw materials on the properties of sustainable LWAs.
All the raw materials were benefited and later analyzed by laser
granulometry, scanning electron microscopy (SEM), X-ray fluorescence
(FRX), X-ray diffraction (XRD) and simultaneous thermal analysis
(STA). Then 50 distinct mixtures were formulated from the substitution
of clay for up to 100% of residues. The samples were dried and then
sintered at 1100, 1150, 1200 and 1250 ° C. The manufactured aggregates
were then characterized by analysis of swelling index (BI), mass loss
(LOI), particle density (ρd), water absorption (WA24H), crush strength
(S), mineralogical composition, thermogravimetric behavior and
microstructure. Finally, the feasibility of using manufactured LWAs was
evaluated by comparative analysis with commercial LWAs. The
resulting aggregates showed a maximum (BI) of 77.44%, (LOI) of up to
43.6%, (ρd) ranging from 0.63 to 2.01 g / cm³, (WA24H) of a minimum
of 0.7%. and (S) up to 17.3 MPa. In all, 102 specimens have
demonstrated properties at least similar to those found in commercial
LWAs, showing the possibility of use in at least 1 major application of
this product in engineering works and services. The results obtained in
this experimental program reveal that it is technically feasible to use
RPS, SS and RHA to produce lightweight aggregates with properties
suitable for major commercial LWA applications. In addition, it was
found that sintering temperature and raw material proportions exert a
strong influence on the main properties of LWAs, and that the prediction
of swelling based on the chemical composition of the mixtures proved to
be unreliable when applied to elaborated LWAs. with RPS, SS and RHA.


MEMBROS DA BANCA:
Presidente - 022.621.844-96 - MARCOS ALYSSANDRO SOARES DOS ANJOS - IFRN
Interno - 028.307.994-02 - ENIO FERNANDES AMORIM - IFRN
Externo à Instituição - NORMANDO PERAZZO BARBOSA - UFPB
Notícia cadastrada em: 17/10/2019 13:54
SIGAA | Superintendência de Tecnologia da Informação - (84) 3342 2210 | Copyright © 2006-2024 - UFRN - sigaa03-producao.info.ufrn.br.sigaa03-producao