1. Sources

The present Combustion File is part of the cluster of CFs produced within the literature survey phase of the industrial sponsored research and development project PowerFlam1 and is confidential to the participants registered for that project.

This CF is specifically concerned with the research project:

Heinzel T., Siegle, V., Spliethoff H., and Hein, K.R.G. (1998): Investigation of slagging in pulverized fuel co-combustion of biomass and coal at a pilot-scale test facility which is published within the Journal of Fuel Processing Technology, Vol. 54, pp. 109-125.

2. Background

·         This combustion file is concerned with the provision of combustion related data to the sponsors.

·         In this html file the source of the data is summarised in section 4 below, in order to give the reader a general overview of the way the data was collected.

·         Fuel and related data, prepared for calculation, are presented in individual Microsoft Excel Worksheets, all contained within a Workbook.

·         Please note that in some cases, the worksheet tabs within a workbook are not all visible without scrolling horizontally.

·         This workbook can be down-loaded by the reader and saved to her/his hard disk.

·         To achieve this click on the “xls” icon on the left hand side of the banner above. The file will be retrieved from the server, and with up-to-date versions of the browser, will appear in a separate window, from which it may be saved to the user’s hard disk.

·         The data in these worksheets are protected – thus the reader cannot change the worksheet without knowledge of the protection password.

·         However the reader can copy and paste the data into his/her own project work book as required – at this point the accuracy and integrity of the data becomes the responsibility of the reader. Included in this workbook are copies of the abstract and synopsis for reference purposes.

·         All credits and sources, and where necessary, instructions/advice for data use, are presented in this html file. These are not necessarily reproduced in the Excel Work Sheets.

3. Abstract

One option to reduce the CO₂ emissions is biomass used for energy production. Co-combustion of biomass in existing coal-fired power stations offers a great potential. In pulverized coal combustion facilities, one implementation problem is the tendency of slagging and fouling of biomass. At the IVD, experiments were carried out to obtain information about biomass deposit characteristics in pulverized fuel pf co-combustion. This paper presents results from the IVD 0.5 MW pf combustion experimental facility obtained from different tests with coal–biomass mixtures ranging from small biomass shares up to a pure biomass firing. Samples of fuels, the fly ash path, deposition and slagging probes, and slags on furnace walls were taken. The amounts of deposits found on probes inserted into the combustion chamber, their macroscopic characteristics, elemental composition and fusion temperatures were analyzed and compared. Generally, the deposits from the co-combustion experiments softened in ash fusion tests like the main component (coal ash) rather than like a mixture. When co-firing biomass with 25% of thermal input, no slagging was detected on cooled probes at 650 ^oC in the flue gas at 1050 ^oC. Most deposit samples from the probes softened at higher temperatures compared to the laboratory-made ash and as expected for a mixture, but melted as mixtures are expected to. Slagging occurred on uncooled refractory samples, at higher biomass shares, and when the biomass particles were not completely burnt out and sticky when reaching the probes.

4. Synopsis