Abstract:
The iron and steel-making industries have garnered significant attention in research related to low-carbon transitions and the reuse of steel slag. This industry is known for its high carbon emissions and the substantial amount of steel slag it generates. To address these challenges, a waste heat recovery process route has been developed for molten steel slag, which integrates CO2 capture and fixation as well as efficient utilization of steel slag. This process involves the use of lime kiln flue gas from the steel plant as the gas quenching agent, thereby mitigating carbon emissions and facilitating carbonation conversion of steel slag while simultaneously recovering waste heat. The established carbonation model of steel slag reveals that the insufficient diffusion of CO2 gas molecules within the product layer is the underlying mechanism hindering the carbonation performance of steel slag. This finding forms the basis for enhancing the carbonation performance of steel slag. The results of Aspen Plus simulation indicate that 1 t of steel slag (with a carbonation conversion rate of 15.169 %) can fix 55.19 kg of CO2, process 6.08 kmol of flue gas (with a carbon capture rate of 92.733 %), and recover 2.04 GJ of heat, 0.43 GJ of exergy, and 0.68 MWh of operating cost. These findings contribute to the development of sustainable and efficient solutions for steel slag management, with potential applications in the steel production industry and other relevant fields.
摘要:
钢铁工业在与低碳过渡和钢渣再利用有关的研究中引起了极大的关注。该行业以其高碳排放和其产生的大量钢渣而闻名。为了应对这些挑战,开发了钢渣余热回收工艺路线,它集成了CO2捕获和固定以及钢渣的有效利用。该工艺涉及使用钢铁厂的石灰窑烟气作为气体淬火剂,从而减少碳排放并促进钢渣的碳化转化,同时回收废热。所建立的钢渣碳化模型揭示了CO2气体分子在产品层内扩散不足是阻碍钢渣碳化性能的潜在机理。这一发现为提高钢渣的碳化性能奠定了基础。AspenPlus模拟结果表明,1t钢渣(碳酸化转化率为15.169%)可以固定55.19kgCO2,处理6.08kmol烟气(碳捕获率为92.733%),并回收2.04GJ的热量,0.43GJ的火用,和0.68兆瓦的运行成本。这些发现有助于开发可持续和有效的钢渣管理解决方案,在钢铁生产行业和其他相关领域具有潜在的应用。