Desulfurization Characteristics of Rapidly Hydrated Sorbents with Various Adhesive Carrier Particles for a Semidry CFB-FGD System

Abstract

Semidry flue gas desulfurization (FGD) experiments were conducted using rapidly hydrated sorbents with four different adhesive carrier particles: circulation ash from a circulating fluidized bed boiler (CFBB circulation ash), fly ash from the first electrical field of the electrostatic precipitator of a circulating fluidized bed boiler (CFBB ESP ash), fly ash from a chain boiler (chain boiler ash), and river sand smaller than 1 mm. The influences of various adhesive carrier particles and operating conditions on the desulfurization characteristics of the sorbents were investigated, including sprayed water, reaction temperature, and the ratio of calcium to sulfur (Ca/S). The experimental results indicated that the rapidly hydrated sorbents had better desulfurization characteristics by using adhesive carrier particles which possessed better pore, adhesion, and fluidization characteristics. The desulfurization efficiency of the system increased as the reaction temperature decreased, it improved from 35% to 90% as the mass flow rate of the sprayed water increased from 0 to 10 kg/h, and it increased from 65.6% to 82.7% as Ca/S increased from 1.0 to 2.0. Based on these findings, a new semidry circulating fluidized bed (CFB)-FGD system using rapidly hydrated sorbent was developed. Using the rapidly hydrated sorbent, this system uses a cyclone separator instead of an ESP or a bag filter to recycle the sorbent particles, thereby decreasing the system flow resistance, saving investment and operating costs of the solids collection equipment.

Study on the Flow Characteristics of Desulfurization Ash Fine Particles in a Circulating Fluidized Bed

“…As shown in Table 1, many scholars have studied the flue gas desulfurization process by experiment or simulation [25][26][27][28][29]. Table 1 shows that research on circulating fluidized bed flue gas desulfurization is mostly focused on improving the adsorbent's adsorbability [30][31][32][33][34][35][36][37], improving the pore structure of the adsorbent [31,[38][39][40], and establishing different desulfurization models [41][42][43] to improve the utilization rate of the desulfurizing agent. Li et al [42] established a mass balance model using fast hydrating adsorbents, and predicted the system status from the aspects of particle wear, particle residence time, particle segregation, and the desulfurization process, and optimized operating conditions.…”

Supported Polytertiary Amines: Highly Efficient and Selective SO2 Adsorbents

“…Furthermore, as demonstrated by Uyanga et al and Supap et al, monoethanolamines deactivate during the FGD process via formation of heat stable sulfate. Although other methods including semidry FGD, dry FGD, ammonium FGD, and electron beam FGD have some unique advantages, they always suffer from low desulfurization efficiency, high operation cost, difficulty of SO 2 recovery, or undesirable secondary pollution …”

Synthesis and Desulfurization Performance of Functional Silica Gel Modified by Polymeric 1-Vinyl-3-ethylimidazolium Tetrafluoroborate Ionic Liquids

“…8−11 Besides, HDS is carried out under high temperature and pressure and with high energy costs. 12, 13 Consequently, it is essential to develop novel non-HDS technologies, which involve extractive desulfurization, 8,12 oxidation desulfurization, 14,15 adsorption desulfurization, 16,17 biodesulfurization, 18, 19 and oxidation−extractive desulfurization, 10,20−22 etc. Recently, ionic liquids (ILs) have been widely studied as a type of novel solvent, 23,24 catalysis, 25,26 gas separation, 27,28 electrochemistry, 29,30 and so on as their satisfactory physical and chemistry properties. As a new style of green solvent, ILs are environmentally and moderate extraction agent for aromatic sulfur-containing compounds because of their unique properties, such as negligible vapor pressure, high thermal and chemical stability and immiscibility with most of nonpolar organic solvents, etc.…”

“…The traditional industrial method for removing organic sulfur-containing compounds from fuels is catalytic hydrodesulfurization (HDS), which is highly efficient in removing aliphatic and alicyclic sulfur compounds but less effective for aromatic sulfur compounds such as thiophene (TS), benzothiophene (BT), dibenzothiophene (DBT), and their derivatives. − Besides, HDS is carried out under high temperature and pressure and with high energy costs. , Consequently, it is essential to develop novel non-HDS technologies, which involve extractive desulfurization, , oxidation desulfurization, , adsorption desulfurization, , biodesulfurization, , and oxidation–extractive desulfurization, ,− etc.…”