A Slag Management Toolset for Determining Optimal Coal Gasification Temperatures
-
Kyei‐Sing Kwong
and
James P. Bennett
Abstract
Gasifier operation is an intricate process because of the complex relationship between slag chemistry and temperature, limitations of feedstock materials, and operational preference. High gasification temperatures increase refractory degradation, while low gasification temperatures can lead to slag buildup on the gasifier sidewall or exit, either of which are problematic during operation. Maximizing refractory service life and gasifier performance require finding an optimized operating temperature range which is a function of the coal slag chemistry and viscosity. Gasifier operators typically use a slag’s viscosity-temperature relationship and/or ash-fusion fluid temperature to determine the gasification temperature range. NETL has built a slag management toolset to determine the optimal temperature range for gasification of a carbon feedstock. This toolset is based on a viscosity database containing experimental data, and a number of models used to predict slag viscosity as a function of composition and temperature. Gasifier users typically have no scientific basis for selecting an operational temperature range for gasification, instead using experience to select operational conditions. The use of the toolset presented in this paper provides a basis for estimating or modifying carbon feedstock slags generated from ash impurities in carbon feedstock.
Disclaimer
“This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.”
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©2016 by De Gruyter
Articles in the same Issue
- Frontmatter
- An Experimental and Numerical Study on Orthogonal Machining of Ti–6Al–4V Alloy
- Formation of Chromium-Containing Molten Salt Phase during Roasting of Chromite Ore with Sodium and Potassium Hydroxides
- Slag Formation – Thermodynamic Aspects and Experimental Observations
- A Slag Management Toolset for Determining Optimal Coal Gasification Temperatures
- A Review on Strategic Positioning of Bottleneck around the Customer Order Decoupling Point and Issues on Production Planning in Supply Chain
- Investigation on Effect of Machining Parameters of End Milling on Surface Finish and Temperature Using Taguchi Technique
- Multi-Objective Optimization of HAZ Characteristics for Submerged Arc Welding of Micro-Alloyed High Strength Pipeline Steel using GRA-PCA Approach
Articles in the same Issue
- Frontmatter
- An Experimental and Numerical Study on Orthogonal Machining of Ti–6Al–4V Alloy
- Formation of Chromium-Containing Molten Salt Phase during Roasting of Chromite Ore with Sodium and Potassium Hydroxides
- Slag Formation – Thermodynamic Aspects and Experimental Observations
- A Slag Management Toolset for Determining Optimal Coal Gasification Temperatures
- A Review on Strategic Positioning of Bottleneck around the Customer Order Decoupling Point and Issues on Production Planning in Supply Chain
- Investigation on Effect of Machining Parameters of End Milling on Surface Finish and Temperature Using Taguchi Technique
- Multi-Objective Optimization of HAZ Characteristics for Submerged Arc Welding of Micro-Alloyed High Strength Pipeline Steel using GRA-PCA Approach
