Water Retention Characteristics of Porous Ceramics Produced from Waste Diatomite and Coal Fly Ash

Abstract

Abstract-This study examines potential waste diatomite and coal fly ash reuse to prepare water absorption and retain porous ceramics. The operating conditions are constant pressure (5 MPa), sintering temperature (1000-1270°C), sintering time (2 h), waste diatomite containing coal fly ash at different proportions (0-20%), respectively. The porous ceramic samples containing coal fly ash show low thermal conductivity properties (0.278-0.349 W/mK), probably owing to the more pores than those in the concrete (1.458 W/mK). Water release (t1/2 value) by the porous ceramic samples is decelerated by porous ceramic samples containing coal fly ash, due to the synergy effect of high water absorption by the coal fly ash and better than in the foamed glass material (4 h). Porous ceramic samples containing coal fly ash is highly promising for use in water absorption and retention applications.

Fabrication of Porous Ceramic-Geopolymer Based Material to Improve Water Absorption and Retention in Construction Materials: A Review

“…The microstructure and mechanical properties are known to depend strongly on the chemical compositions of the starting materials [2,5,6]. Geopolymers exhibit a wide variety of properties and characteristics, including high compressive strength, low shrinkage, high temperature resistance [8] and acid and fire resistance [9,10], and seem to be a desirable alternative to ordinary Portland cement and environmentally sustainable characteristics [10,11].…”

“…The compressive strength is the crucial index of the engineering quality of porous ceramic material. The sintering temperatures were varied to obtain the optimum temperature for fabricating the porous ceramic [2]. Table I shows the compressive strength test results for porous ceramics made from diatomite and coal fly ash mixtures.…”

“…The compressive strength of the mixed porous ceramic samples of diatomite that contained the coal fly ash decreased slightly when the sintering temperature increased above 1200°C. The porous diatomite ceramic strength decreased when up to 20% of the coal fly ash was added to the porous ceramics that were heated to 1200°C [2]. Table 1.…”

“…The large amounts of coal fly ash in the porous ceramic samples also facilitated a slow water release, which yielded acceptable water-retention properties. These properties make the porous ceramic samples containing coal fly ash samples promising for use as water-retaining materials to combat this rising temperatures effects [2]. Li L et al also reported about the use of vermiculite as a cementitious material in agricultural field which also known as 'planting concrete'.…”

“…Porous ceramics finds it a lot of new applications in industrial areas, however, because the porosity of ceramic material can be arranged in a well-defined and homogeneous manner or heterogeneously on the other hand and offers the ceramic material many special characteristics ranging from an increased surface area, to permeability, to the control of heat transport within the structure, to the maximization of the strength and density ratio. Materials containing tailored porosity exhibit special properties and features that usually cannot be achieved by their conventional dense counterparts [2]. Water absorption and retention of porous ceramics as building materials are characterized by their permanence, heat insulation and water retention.…”