Рекомендации по снижению абразивного износа гидротранспортных трубопроводов систем золошлакоудаления ТЭС

Abstract

In the vast majority of cases, hydraulic ash and slag removal systems are used for conveying ash and slag at the coal-fired thermal power plants (TPPs) in Russia. Such technical solutions related to the evacuation of slag from boilers and transportation of fly ash after electrostatic precipitators have been replicated since the Soviet times. Hydraulic ash and slag removal systems cause significant damage to the natural environment in the area of coal-fired TPPs location. It should be noted, that the average age of TPPs is about 45-50 years. The inter-repair period and reliable operation of pipelines of TPP ash and slag removal systems significantly depend on abrasive wear, which is one of the main problems when transporting fine bulk materials like ash and slag. Abrasive wear or erosion in pipelines leads to a decrease in the reliability of the entire wet ash removal system; there is a need for the unplanned downtime caused by fistulas in pipelines, resulting in the release of ash and slag slurry into the environment. In addition, the thinning of the c'u'u pipeline wall thickness leads to the increase in the diameter of pipes, which, in turn, leads to deterioration in the eco- au'a nomic efficiency of transporting the ash and slag slurry. The article deals with the problem of abrasive wear of slurry pipelines of TPP ash and slag removal systems. Based on the research results, the main measures for extending the service life of straight and shaped sections of pipelines of TPP wet ash and slag removal systems are described. In order to reduce the intensity of abrasive wear, it is possible to apply regime measures that do not require investment in the reconstruction of existing hydrotransport installations. These measures include: turning the straight horizontal and inclined sections of pipelines around their axis; transporting the slurry with optimal parameters. In addition to the mentioned group of measures, constructive measures are considered that require investment in the reconstruction of hydrotransport installations to varying degrees, such as: optimizing the shape of curvilinear sections of pipelines; performing sections of hydrodynamic flow stabilization at the entrance and exit of the curvilinear (shaped) sections of pipelines, taking into account the zone of maximum wear; anti-abrasive inserts in the shaped sections of pipelines; stone-cast products; pipes with an aluminum-thermal coating. The maximum effectiveness of implementing anti-abrasive recommendations is achieved by combining regime and constructive measures.