Performance Evaluation of Refractory Composite Coatings in Potassium Rich Environment

Kristina Brinkienė,Irena Lukošiūtė,Regina Kalpokaitė-Dičkuvienė,Jūratė Čėsnienė

doi:10.5755/j01.ms.22.3.8348

Kristina Brinkienė, Irena Lukošiūtė + Show 2 more

Open Access

https://doi.org/10.5755/j01.ms.22.3.8348

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Journal: Materials Science	Publication Date: Sep 1, 2016
License type: publisher-specific-oa

Affiliation: Lithuanian Energy Institute

Abstract

A laboratory scale method was used to study the performance of reinforced cement composites in potassium rich environment of biomass combustion. Buckwheat husk (BH) was used as potential source of unexploited biomass product applicable as biomass derived fuel. In order to enhance the alkali effect on the properties of the investigated materials, the solution of potassium carbonate (K2CO3) was selected as potassium rich aggressive environment. Two reinforced cement composites as potential repair coatings for restoration of damaged refractory surfaces with different composition of aggregate were used in corrosion tests. Performance of refractory coatings was evaluated by analysing the microstructure of the treated composites as well as mechanical properties. Energy-dispersive X-ray spectroscopy (SEM/EDS) and optical microscopy were used to study the microstructure in the corroded region of the refractory coatings. Long term studies in the solution of 1M K2CO3 for 56 months have demonstrated that composite with the additive of fluid cracking catalyst of oil refinery and petrochemical industries is more durable in the potassium rich environment.DOI: http://dx.doi.org/10.5755/j01.ms.22.3.8348

Highlights

Refractory materials are widely used in various high temperature environments to insulate and protect internal linings of heat equipments [1 – 3]
The termogravimetric curve (TG) presents the first event of the thermal decomposition in the temperature interval of 25 – 180 °C, which corresponds to the dehydration of the material
At the depth of 0.5 mm from contact zone up to 17 – 20 % higher concentration of potassium was detected for R1 and R2, respectively, than after the test in Buckwheat husk (BH) combustion environment

Summary

Introduction

Refractory materials are widely used in various high temperature environments to insulate and protect internal linings of heat equipments [1 – 3]. High temperature and chemically aggressive environment, even in presence of small amount of corrodients, may cause a damage of the lining. Co-firing of fossil fuels with agro-biomass can significantly reduce CO2 emissions. According to [5, 6], calcium (Ca) and magnesium (Mg) usually increase the ash melting point, while potassium (K) decreases it. This causes sintering or slag formation as well as hard deposit formation on cooled furnace walls [5]

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