Avaliação de desempenho e emissões de caldeiras de vapor híbridas aplicada à biomassa

Abstract

The use of hybrid boilers, resulting from the conjunction of the flame-tube design model with the water-tube one, has been widely spread in the industrial environment as a technological alternative proper to solid biomass combustion to be more efficient and for producing lower emission of pollutants. However, few data are available on the actual operating conditions of this type of boiler in the industrial environment, concerning the performance and emissions, such as: carbon monoxide, nitrogen oxides, unburned hydrocarbons and particulate matter, among others. For this reason, there exist interest in evaluating this question on the spot, especially focusing the performance and emissions, but also on operational safety aspects, the light of applicable regulatory standards. In this context, this Completion Work of Renewable Energy Engineering Course lends itself to identify non-compliances of a steam thermal facilities, through case study, where it is possible to apply some principles of Classical Thermodynamics to the process analysis and Standards of Building and Operation for steam boiler (NRs) as a reference to characterize the facility conditions, in terms of assets. For this reason, it was opted by a detailed data survey on the use of such equipment in the industry, divided into two parts: i) visits to several heating systems, checking if possible the assembled and disassembled systems for analysis of structural conditions; and ii) study of a thermal system of steam generation biomass into a relatively modern facility, owned by a large business organization, to serve as a benchmark for comparative assessment. From this work, it was possible to have a relatively consistent view on operational problems and risks, which are present in this type of industrial facility, focused on the use of solid biomass, encompassing the components of the installation accessories, on scope of Ceará province. Some irregularities were checked out, especially concerning the preventive maintenance routine and compliance with NR-13, particularly regarding instrument calibration, as well as CO and NOx emissions exceeding the specifications of the manufacturer and international standards were detected, based on ISO standard.