Banca de DEFESA: CINTHIA DE SOUZA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : CINTHIA DE SOUZA
DATE: 21/08/2024
TIME: 14:00
LOCAL: meet.google.com/sjv-bvzh-tck
TITLE:

TECHNICAL AND ECONOMIC FEASIBILITY STUDY OF THE USE OF SLUDGE NEUTRAL AS AN ALTERNATIVE PRODUCT TO PLASTER BASED IN CONSTRUCTION

KEY WORDS:

Gypsum; Neutral Sludge; Coating; Civil Construction.

PAGES: 172
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Cerâmicos
SUMMARY:

The main materials used in this work were neutral sludge produced by the company Nexa in one of its plants in Cajamaquilla, Peru and commercial gypsum. The technical and economic feasibility of reusing neutral sludge in the form of a blend (mixture of neutral sludge and commercial plaster) as a coating for civil construction was evaluated. According to Nexa (2022), neutral sludge refers to a type of waste generated in wastewater treatment processes, being a product originating from the biological and physical-chemical purification process, where most contaminants are eliminated. present in wastewater. The studies carried out with this material consisted of evaluating the physical-chemical and mechanical properties of mixtures of sludge and commercial gypsum, with percentages by weight of sludge in relation to pure commercial gypsum (control material) that varied between 10%, 20%, 30%, 40% and 50%. The samples were characterized in powder form through thermal, mineralogical and granulometric analyses. In the fresh state, the samples underwent setting time analysis. In the hardened state, the compressive and tensile strengths were evaluated. To carry out the economic viability analysis, consultancy was hired from the company FEA Junior from USP - SP, which through specialists carried out the gypsum market study, considering the Peruvian market. The results suggest that all traits were within the American Standard C28/C28M for compressive strength, and within NBR 13528-2 and the European Standard EN 13279-1 for tensile adhesion strength. Although the 30% mix without additive met these standards, there were difficulties during testing due to the reduced setting time. When applying the blend to the wall, according to the considerations of the applicator hired to do the service, the 20% percentage without additive was easy to apply, but it dried quickly, this quick drying according to a professional is an advantage in relation to plaster commercial. With a percentage of 50% with Blok Gesso additive, the applicator reported the occurrence of accelerated drying, but stated that this characteristic made the finish easier compared to commercial plaster. Given the results, it was possible to conclude that it is technically viable to use a blend of neutral sludge and commercial plaster as wall coverings in civil construction, with a percentage of 20% without additive and percentages of 30% to 50% with an additive being able to be used. However, for use on large scales, especially for mixes with higher percentages of neutral sludge (40% and 50%), it may be necessary to adjust the amount of additive to obtain better setting times. According to the economic viability analysis carried out by FEA Junior at USP - SP, it was observed that civil construction is a promising market to direct the production of the blend, using as a parameter mainly the correlation between the two markets and the indication that the demand for plaster in civil construction overlaps with the sum of other markets that use plaster for other purposes, however, according to studies, the application of the blend as an alternative product to plaster should not be limited to wall coverings, it should be considered also the hypotheses of application in the production of Drywall and in the cement industry, thus adding value to the product produced.

COMMITTEE MEMBERS:
Presidente - 1337089 - FABRÍCIO VIEIRA DE ANDRADE
Interno - 395189 - ANTONIO JOSE FARIA BOMBARD
Externo ao Programa - 1535075 - CARLOS AUGUSTO DE SOUZA OLIVEIRA - UNIFEIExterno à Instituição - FERNANDO SOARES LAMEIRAS - CDTN