Briquetting of waste glass cullet fine particles for energy saving glass manufacture

Abstract

Briquetting of waste glass cullet fine particles for energy-saving glass manufacture.

Exploratory research in alternative raw material sources and reformulation for industrial soda‐lime‐silica glass batches

“…The spectra indicate that the reformulated CC glass composition is almost the same, in terms of optical transmission properties, as the benchmark glass. A weak optical absorption band centered at 380 nm appears in all three spectra, which can be attributed to the 6 A 1 (S) → 4 E(D) transition of tetrahedrally coordinated Fe 3+ cations . Theoretically, network modifiers in silicate glass can produce a significant shift of the UV edge to longer wavelengths .…”

“…The presence of high levels of amorphous content suggests that these materials may form liquid phases more readily than the crystalline materials they partially replace during glass melting, and thus may require less energy to melt (owing to the absence of latent heats of melting associated with changes of state, combined with no decomposition reactions to drive) compared with the standard raw materials such as silica sand, soda ash, or limestone. This could conceivably enable specific energy consumption savings through reducing the time the raw materials need to spend in the furnace in order to fully dissolve sand grains and completely form the liquid phase …”

Melting behavior of waste glass cullet briquettes in soda‐lime‐silica container glass batch

“…Consequently, up to 20 wt% of all recycled cullet is currently land filled as a waste. To extend and secure glass batch sources, by recycling cullet fines and alleviating uptake of landfill facilities (of which there are shortages), a primary study of the recycling of cullet fines through briquetting and re‐introduction into representative container glass batches and products, and its effects therein, has been described recently by the present authors . Briquettes consisting of 82 wt% recycled cullet fines were made with additions of sodium silicate, sodium carbonate, and water.…”

“…The compressive strength of briquettes was shown to increase linearly with time, increasing from 2 MPa to 60‐65 MPa after 33 days at room temperature (ca. 20°C) and ambient humidity . With compensation of the other glass batch materials to maintain a consistent nominal final glass composition, it was demonstrated that up to 15 wt% briquettes could be added to a representative green container glass batch, and produce glasses with comparable compositions and properties to glasses produced using briquette‐free batches, supporting the potential use of this technology for enhanced energy and resource efficiency, and lower CO 2 emissions, from commercial glass manufacture through increased cullet usage.…”

“…Their calculations indicated that the activation energy for decomposition of carbonate in granulated batch is lower than that of loose batch: granulation promoted the decomposition of carbonate raw materials during melting and the activation energy decreased with increasing binder (carboxyl methyl cellulose) solution concentration. Few investigations have been carried out on the melting behavior of briquetted glass raw materials and, to our knowledge, none had previously studied briquetted glass fines prior to our recent study …”