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Title: Utilization of lightweight materials made from coal gasification slags. Quarterly report, September 15--November 30, 1994

Abstract

Coal gasification technologies are finding increasing commercial applications for power generation or production of chemical feedstocks. The integrated-gasification-combined-cycle (IGCC) coal conversion process has been demonstrated to be a clean, efficient, and environmentally acceptable method of generating power. However, the gasification process produces relatively large quantities of a solid waste termed slag. Regulatory trends with respect to solid waste disposal, landfill development costs, and public concern make utilization of slag a high-priority issue. Therefore, it is imperative that slag utilization methods be developed, tested, and commercialized in order to offset disposal costs. This project aims to demonstrate the technical and economic viability of the slag utilization technologies developed by Praxis to produce lightweight aggregates (LWA) and ultra-lightweight aggregates (ULWA) from slag in a large-scale pilot operation, followed by total utilization of these aggregates in a number of applications.

Publication Date:
Research Org.:
Praxis Engineers Inc., Milpitas, CA (United States)
Sponsoring Org.:
USDOE Assistant Secretary for Fossil Energy, Washington, DC (United States)
OSTI Identifier:
650103
Report Number(s):
DOE/MC/30056-5747
ON: DE97053935; TRN: AHC2DT04%%14
DOE Contract Number:
FC21-94MC30056
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Jul 1997
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; PROGRESS REPORT; SLAGS; WASTE PRODUCT UTILIZATION; GRANULAR MATERIALS; MATERIALS TESTING; COAL GASIFICATION PLANTS

Citation Formats

NONE. Utilization of lightweight materials made from coal gasification slags. Quarterly report, September 15--November 30, 1994. United States: N. p., 1997. Web. doi:10.2172/650103.
NONE. Utilization of lightweight materials made from coal gasification slags. Quarterly report, September 15--November 30, 1994. United States. doi:10.2172/650103.
NONE. Tue . "Utilization of lightweight materials made from coal gasification slags. Quarterly report, September 15--November 30, 1994". United States. doi:10.2172/650103. https://www.osti.gov/servlets/purl/650103.
@article{osti_650103,
title = {Utilization of lightweight materials made from coal gasification slags. Quarterly report, September 15--November 30, 1994},
author = {NONE},
abstractNote = {Coal gasification technologies are finding increasing commercial applications for power generation or production of chemical feedstocks. The integrated-gasification-combined-cycle (IGCC) coal conversion process has been demonstrated to be a clean, efficient, and environmentally acceptable method of generating power. However, the gasification process produces relatively large quantities of a solid waste termed slag. Regulatory trends with respect to solid waste disposal, landfill development costs, and public concern make utilization of slag a high-priority issue. Therefore, it is imperative that slag utilization methods be developed, tested, and commercialized in order to offset disposal costs. This project aims to demonstrate the technical and economic viability of the slag utilization technologies developed by Praxis to produce lightweight aggregates (LWA) and ultra-lightweight aggregates (ULWA) from slag in a large-scale pilot operation, followed by total utilization of these aggregates in a number of applications.},
doi = {10.2172/650103},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jul 01 00:00:00 EDT 1997},
month = {Tue Jul 01 00:00:00 EDT 1997}
}

Technical Report:

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  • Coal gasification technologies are finding increasing commercial applications for power generation or production of chemical feedstocks. The integrated-gasification-combined-cycle coal conversion process has been demonstrated to be a clean, efficient, and environmentally acceptable method of generating power. However, the gasfication process produces relatively large quantities of a solid waste termed slag. Regulatory trends with respect to solid waste disposal, landfill development costs, and public concern make utilization of slag a high-priority issue. Therefore, it is imperative that slag utilization methods be developed, tested, and commercialized in order to offset disposal costs. In previous projects, Praxis investigated the utilization of ``as-generated`` slagsmore » for a wide variety of applications in road construction, cement and concrete production, agricultural applications, and landfill. We determined that it would be extremely difficult for ``as-generated`` slag to find acceptance in the marketplace even at no cost because the materials it could replace were abundantly available at very low cost. It became apparent that a more promising approach would be to develop a variety of value-added products from slag that would meet specific industry requirements. This approach was made feasible by the discovery that slag could be made into a lightweight material by heating it to between 1600 and 1900{degree}F in a kiln, which indicated the potential for using such materials as substitutes for lightweight aggregates. Between 1987 and 1993, the technologies to produce these materials from slag were developed by Praxis with funding from the Electric Power Research Institute, Illinois Clean Coal Institute, and internal resources.« less
  • In previous projects, Praxis investigated the utilization of as-generated slags for a wide variety of applications in road construction, cement and concrete production, agricultural applications, and as a landfill material. From these studies, the authors found that it would be extremely difficult for as-generated slag to find large-scale acceptance in the marketplace even at no cost because the materials it could replace were abundantly available at very low cost. It became apparent that a more promising approach would be to develop a variety of value-added products from slag that meet specific industry requirements. This approach was made feasible by themore » discovery that slag undergoes expansion and forms a lightweight material when subjected to controlled heating in a kiln at temperatures between 1,400 and 1,700 F. These results confirmed the potential for using expanded slag as a substitute for conventional lightweight aggregates (LWA). The technology to produce lightweight and ultra-lightweight aggregates (ULWA) from slag was subsequently developed by Praxis. The major objectives of the subject project are to demonstrate the technical and economic viability of commercial production of LWA and ULWA from slag and to test the suitability of these aggregates for various applications. The project goals are to be accomplished in two phases: Phase 1, comprising the production of LWA and ULWA from slag at the large pilot scale, and Phase 2, which involves commercial evaluation of these aggregates in a number of applications. This document summarizes the Phase 2 accomplishments to date along with the major accomplishments from Phase 1.« less
  • Integrated-gasification combined-cycle (IGCC) technology is an emerging technology that utilizes coal for power generation and production of chemical feedstocks. However, the process generates large amounts of solid waste, consisting of vitrified ash (slag) and some unconverted carbon. In previous projects, Praxis investigated the utilization of {open_quotes}as-generated{close_quotes} slags for a wide variety of applications in road construction, cement and concrete production, agricultural applications, and as a landfill material. From these studies, we found that it would be extremely difficult for {open_quotes}as-generated{close_quotes} slag to find large-scale acceptance in the marketplace even at no cost because the materials it could replace were abundantlymore » available at very low cost. It was further determined that the unconverted carbon, or char, in the slag is detrimental to its utilization as sand or fine aggregate. It became apparent that a more promising approach would be to develop a variety of value-added products from slag that meet specific industry requirements. This approach was made feasible by the discovery that slag undergoes expansion and forms a lightweight material when subjected to controlled heating in a kiln at temperatures between 1400 and 1700{degrees}F. These results confirmed the potential for using expanded slag as a substitute for conventional lightweight aggregates (LWA). The major objectives of the subject project are to demonstrate the technical and economic viability of commercial production of LWA and ULWA from slag and to test the suitability of these aggregates for various applications.« less
  • Integrated-gasification combined-cycle (IGCC) technology is an emerging technology that utilizes coal for power generation and production of chemical feedstocks. However, the process generates large amounts of solid waste, consisting of vitrified ash (slag) and some unconverted carbon. Slag undergoes expansion and forms a lightweight material when subjected to controlled heating in a kiln. The potential exists for using expanded slag as a substitute for conventional lightweight aggregates (LWA). The technology to produce lightweight and ultra-lightweight aggregates (ULWA) from slag was subsequently developed. The project scope consists of collecting a 20-ton sample of slag (primary slag), processing it for char removal,more » and subjecting it to pyroprocessing to produce expanded slag aggregates of various size gradations and unit weights, ranging from 12 to 50 lb/ft{sup 3}. A second smaller slag sample will be used for confirmatory testing. The expanded slag aggregates will then be tested for their suitability in manufacturing precast concrete products (e.g., masonry blocks and roof tiles) and insulating concrete, first at the laboratory scale and subsequently in commercial manufacturing plants. These products will be evaluated using ASTM and industry test methods. Technical data generated during production and testing of the products will be used to assess the overall technical viability of expanded slag production. In addition, a market assessment will be made based on an evaluation of both the expanded slag aggregates and the final products, and market prices for these products will be established in order to assess the economic viability of these utilization technologies.« less
  • Integrated-gasification combined-cycle (IGCC) technology is an emerging technology that utilizes coal for power generation and production of chemical feedstocks. However, this process generates large amounts of solid waste, consisting of vitrified ash (slag) along with some unconverted carbon, which is disposed of as solid waste. The objectives of this project is to demonstrate the technical and economic viability of slag utilization technologies for commercial production of lightweight aggregates (LWA) and ultra-lightweight aggregates (ULWA) from slag and to test the suitability of these aggregates for various applications. The scheduled date for completing Phase I, which includes production of LWA and ULWAmore » from slag at the large pilot-scale, is 14 December 1995. The scheduled start date for Phase II, which involves commercial utilization of these aggregates in a number of applications, is 15 December 1995, and the scheduled completion date of the project is 14 March 1997.« less