A Novel Stacked Rotary Cup Atomizer Toward Efficient Centrifugal Granulation of Molten Blast Furnace Slag

Abstract

Atomizer is one of the most important facilities in molten slag centrifugal granulation heat recovery system, which concerns the heat recovery rate of the system as well as the quality of slag particles. Aim to large slag flow rate in industrial application, a novel stacked rotary cup atomizer (SRCA) is proposed to achieve high‐quality centrifugal granulation performance. The authentic molten slag is adopted as working medium and the centrifugal granulation phenomena are visually investigated including the molten slag fragmentation on the surface of atomizer and the impacting of slag droplets on the water cooled wall. A film perforation fragmentation mode is found in the experiments under high slag flow rate. The granulated particle size distribution, average particle size, and slagging mass fraction produced by the atomizer are obtained. Moreover, the granulation performances of the SRCA with divergent structures are tested. The results demonstrate that the SRCA has excellent granulation performance in large slag flow rate to produce smaller particles and suppress slagging. Comparing with the typical rotary cup atomizer, the largest decrement in average particle size and slagging mass fraction for the SRCA is ascertained as 28.1% and 71.1%, respectively.

Exploiting the Molten Slag to Decarbonize Iron and Steel Industry: Feasibility Analysis of Centrifugal Granulation‐Assisted Thermal Energy Recovery System beyond Pilot Scale

“…Encouragingly, a high glassy content over 95% inside the slag particle was achieved after air cooling, which rivals that of water-quenching slag. Since then, many efforts have been undertaken to understand the fundamental physics of centrifugal granulation, [14,15] slag granule cooling, [16,17] and heat transfer of slag granules. [18,19] More recently, some pilot-scale CGATER plants have been demonstrated in Australia, [20] Europe, [21] and China.…”