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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Drying behavior of dense refractory castables. Part 2-Drying agents and design of heating schedules

Texto completo
Autor(es):
Luz, A. P. [1] ; Moreira, M. H. [1] ; Salomao, R. [2] ; Braulio, M. A. L. [3] ; Pandolfelli, V. C. [1]
Número total de Autores: 5
Afiliação do(s) autor(es):
[1] Univ Fed Sao Carlos, Grad Program Mat Sci & Engn PPGCEM, Rod Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Sao Paulo, Sao Carlos Sch Engn, Mat Engn Dept, Ave Trabalhador Sao Carlense 400, Sao Carlos, SP - Brazil
[3] Tech Assistance & Consultancy Refractories, Rua Aristides de Santi 6, Un 48, BR-13571150 Sao Carlos, SP - Brazil
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: CERAMICS INTERNATIONAL; v. 48, n. 3, p. 2965-2987, FEB 1 2022.
Citações Web of Science: 0
Resumo

Drying is the most critical process of the first heating cycle of monolithic dense refractories, as the reduced permeability of the resulting microstructure may lead to explosive spalling and mechanical damage associated with dewatering. The first part of this review series pointed out the various drying stages, the role of the binder components and the techniques that can be used to follow the water release in as-cast refractory materials, when they are exposed to heat. Although defining a suitable heating schedule is a great challenge, some tools can be applied to minimize the spalling risks associated with steam pressurization. In this context, this second review article points out (i) the main drying agents and how they affect the resulting castables' microstructure (organic fibers, metallic powders, permeability enhancing active compounds, silica-based additives and chelating agents), and (ii) the effects related to the procedures commonly applied during the designing of heating routine (i.e., the role of the heating rate, ramp versus holding time), as well as the influence of the castable's dimension on the overall drying behavior. Considering the recent advances regarding the design of refractory formulations and their processing, one may expect that incorporating suitable drying additives into the prepared composition should lead to a suitable and safer water release in such dense consolidated structures. Besides that, novel engineering opportunities, such as the use of in-situ based experimental techniques (i.e., neutron and X-ray tomography) to obtain more accurate data and the development of numerical models, might help in simulating and predicting the steam pressure developed in refractory systems during their first heating. Consequently, instead of designing conservative drying schedules based on empirical knowledge, the novel optimized heating procedures should be based on technical and scientific information. (AU)

Processo FAPESP: 18/19773-3 - Refratários microporosos moldáveis no sistema Al2O3-MgO-CaO para isolamento térmico acima de 1200ºC
Beneficiário:Rafael Salomão
Modalidade de apoio: Bolsas no Exterior - Pesquisa
Processo FAPESP: 19/07996-0 - Otimização do processo de secagem de concretos refratários avançados
Beneficiário:Ana Paula da Luz
Modalidade de apoio: Auxílio à Pesquisa - Regular