Details

Autor(en) / Beteiligte

• Chen, Zhichao
• Tian, Xiaodong
• Hou, Jian
• Li, Zhengqi
• Xu, Yongwei
• Feng, Yuanyuan

Titel

Sustainable preparation of high-calorific value and low-N and S energy products through the low-temperature alkali fusion of coal gasification fine ash

Ist Teil von

• Environmental research, 2023-11, Vol.236 (Pt 2), p.116802-116802, Article 116802

Ort / Verlag

Netherlands: Elsevier Inc

Erscheinungsjahr

2023

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Coal gasification fine ash (CGFA) is characterized by high yield, high carbon content, and difficult recovery. This results in waste of coal resources and serious environmental pollution. To address this issue, a novel green deashing process is proposed in this study to modify CGFA into deashed carbon (DAC) with a high calorific value and an ash content of less than 5% through a low-temperature alkaline fusion process. Compared with traditional alkaline fusion (which is carried out at 600–1000 °C), low-temperature alkaline fusion treatment can efficiently remove ash minerals in the temperature range of 300–450 °C, which is beneficial to the efficient recovery of residual carbon in DA, while simultaneously improving the physicochemical properties and energy characteristics of DAC, thereby improving its combustion performance. At an alkali fusion temperature of 350 °C, a NaOH:DA ratio of 4.5:1, and a reaction time of 40 min, the resulting DAC product had ash content of 2.28%, combustible material recovery (CMR) of 82.03%, higher heating value (HHV) of 31.07 MJ kg−1, and SBET of 445.43 m2 g−1. In comparison, it was found that low-temperature alkali fusion significantly improved the deashing of CGFA when compared to existing deashing technologies. These results strongly suggest that this innovative deashing method can modify CGFA into a high-calorific value and low-N and S fuel, thereby providing a cost-effective and sustainable utilization method for CGFA. [Display omitted] •Low-temperature alkaline fusion can achieve green and efficient deashing of CGFA.•The combustible recovery rate of DAC is up to 82.03% and the ash content is 2.28%.•CGFA can be modified into high-calorific value and low-N and S content fuel.•Low-temperature alkali fusion is beneficial to the sustainable treatment of CGFA.