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<p><span style="FONT-SIZE: 12pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;"><font size="6"> 制粉系统和煤尘爆炸及基反事故措施</font></span></p><span style="FONT-SIZE: 12pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;"><font size="6"><p class="MsoNormal" align="left" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-pagination: widow-orphan;"><span style="FONT-SIZE: 12pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-font-kerning: 0pt;">(一)制粉系统和煤尘爆炸的发生<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-pagination: widow-orphan;"><span style="FONT-SIZE: 12pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-font-kerning: 0pt;">引起煤尘爆炸有三方面的因素,燃料和助燃空气的积存;燃料和空气的混合物达到了爆燃的浓度(混合比)、有足够的点火能源。避免三因素的合可以避免煤尘爆炸。电厂锅炉制粉系统运行时,空气煤尘混合物的浓度在爆炸浓度范围之内,点火源可以是积粉自燃,也可以民金属撞击的结果。以下是制粉系统或煤尘爆炸的案例。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-pagination: widow-orphan;"><span style="FONT-SIZE: 12pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-font-kerning: 0pt;">某电厂<span lang="EN-US">3</span>号炉(<span lang="EN-US">670t/h</span>)<span lang="EN-US">2</span>号磨煤机,<span lang="EN-US">32</span>号给煤机销子断,此给煤机因检修而停用。给煤机销子换好后,启动运行时一声巨响发生爆炸,所有也爆门(<span lang="EN-US">21</span>个)全部爆破,排粉机出口风门被打坏掉下,将排粉机叶轮打坏。事故原因是由于磨煤机停运前,未将制粉系统中的煤粉充分清理干净,煤粉自燃,启动时引起制粉系统爆炸。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-pagination: widow-orphan;"><span style="FONT-SIZE: 12pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-font-kerning: 0pt;">某电厂<span lang="EN-US">2</span>号炉停炉小修,停炉后转动给粉机将煤粉仓放空,但未再检查和清扫积粉,结束小修后点火启动。在启动<span lang="EN-US">1</span>、<span lang="EN-US">2</span>号磨煤机向甲煤粉仓进粉过程中未发现异常,但在第二天启动<span lang="EN-US">4</span>号磨煤机向乙煤粉仓进粉时(当时粉仓温度计指示<span lang="EN-US">50℃</span>),<span lang="EN-US">9min</span>后一声巨响,乙煤粉仓爆炸,温度升高到<span lang="EN-US">150℃</span>,仓顶一部分混凝土预制板被掀开,煤粉仓防爆门膜板从边腐蚀处撕开(咬口处爆开),一名输煤值班工被粉仓顶部喷出的火焰和红粉煤烧伤致死。事故直接原因:煤粉仓内壁、栅栏及角落处有少量积粉,检修期间发生自燃,排粉机启动后,自燃加剧,接着启动<span lang="EN-US">4</span>号磨煤机,粉仓内粉尘达到爆炸浓度,遇到自燃煤粉引起爆炸。<span lang="EN-US"><p></p></span></span></p><p></p></font></span> |
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