S4 explorer

A low-rank coal sample was collected from Pingshuo power generation plant in Shanxi Province, China. Proximate analysis and ultimate analysis of the coal sample were performed using a thermogravimetric analyzer (TGA-701, LECO) and an elemental analyzer (vario Macro CHNS, Elementar), respectively, and the calorific value was determined by an adiabatic bomb calorimetry (Parr 6400 Calorimeter, Parr). The results obtained are summarized in Table 2. Additionally, the chemical compositions of the coal ash were determined by X-ray fluorescence (XRF) spectrometer (S4-Explorer, Bruker) and the results are detailed in Table 2. The coal sample was first dried for 24h at 105 ^oC and then crushed and ground to a size smaller than 150 um.
Industrial steel slags were acquired from Shougang Corporation in Beijing, China, the chemical compositions of which were measured by XRF (S4-Explorer, Bruker) and displayed in Table 2. The slag was first crushed into small particles after drying, and then thoroughly mixed with the coal powder using a ball grinder for the subsequent gasification. Three samples were prepared using the foregoing materials, i.e., a raw steel slag sample (S0), a raw coal sample (S1) and a mixture with the mass ratio of coal sample to steel slags of 1:1 (S2), respectively.

The deposited particles were characterized using scanning electron microscopy (SEM, JSM-6400, Jeol, Japan), X-ray diffraction (XRD, Rigaku, Rint2200, Japan) and X-ray fluorescence (XRF, S4-Explorer, Bruker, Germany). The nitrate and nitrite in the supernatant were determined by ion chromatography (881 Pro, Metrohm, Switzerland). The pH value and total organic carbon (TOC) were measured using a pH meter (S210-S, Mettler Toledo, USA) and a TOC analyzer (TOC 500, Shimadzu, Japan), respectively.