DESIGN AND CONSTRUCTION OF A PCI RIG FOR EVALUATION OF PULVERIZED FUELS COMBUSTION: EQUIPMENT FEATURES
PROJETO E CONSTRUÇÃO DE UM SIMULADOR DE PCI PARA COMBUSTÍVEIS SÓLIDOS PULVERIZADOS: CARACTERÍSTICAS DO EQUIPAMENTO
René Lúcio Rech, André da Silveira Machado, Claudia Caroline Teixeira Barbieri, Juliana Gonçalves Pohlmann, Janaina Gonçalves Maria da Silva Machado, Maurício Covcevich Bagatini, Nilson Romeu Marcílio, Antônio Eduardo Clark Peres, Antônio César Faria Vilela, Eduardo Osório
Abstract
Pulverized coal injection (PCI) is a technique worldwide used in blast furnaces (BFs) to reduce coke consumption. Burning of pulverized coal injected into tuyeres of BFs takes place under medium pressure (up to 450 kPa), high flame temperatures (around 2500 K), very fast heating rates (105 –106 K/s) and very short residence times, less than 40 ms. Since there are no standard tests for evaluation of coal combustibility at PCI conditions, lab scale injection rigs are usually employed for this purpose. This work shows relevant characteristics of the injection rig developed by LASID-UFRGS, which operates at automated injection mode. The main rig features are direct measurement of pressure and temperature inside the combustion zone during combustion process, temperature measurement with ultra-fast thermocouples (ms), high speed control and data acquisition (ms) and collection of both solid and gaseous combustion products. First results showed pressure and temperature evolution along throughout the combustion test, with and without sample, combustion gas composition and coal burnout for different coals. Experimental data statistics showed good repeatability for all tested coals.
Keywords
Resumo
A injeção de carvão pulverizado (PCI) é uma técnica utilizada em altos-fornos (AFs) para reduzir o consumo de coque. A queima do carvão pulverizado injetado nas ventaneiras do AF ocorre em pressões médias (até 450 kPa), temperaturas de chama elevadas (cerca de 2500 K), taxas de aquecimento muito elevadas (105 –106 K/s) e tempos de residência muito curtos, abaixo de 40 ms. Como não há testes padronizados para avaliação da combustibilidade de carvões nas condições de PCI, simuladores de combustão em PCI são comumente utilizados para esse fim. Este trabalho apresenta as características relevantes do simulador de PCI desenvolvido pelo LASID-UFRGS, que opera com pulso automatizado de injeção. As características principais do simulador são a medida direta de pressão e temperatura dentro da zona de combustão durante o, a medição de temperatura com termopares ultrarrápidos (ms), a aquisição de dados e controle em alta velocidade (ms) e a coleta dos produtos sólidos e gasosos da combustão. Os primeiros resultados mostraram a evolução da pressão e temperatura durante o pulso de injeção, com ou sem amostra, o grau de conversão (burnout) do carvão e a composição dos gases de combustão para diferentes carvões. A análise estatística dos dados experimentais demonstrou uma boa repetitividade para todos os carvões testados.
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Referências
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