Potencialidades de logística reversa do resíduo de gesso da indústria da construção civil

Abstract

The present study, had as general objective to design the current construction and demolition waste (CDW) and the generation of gypsum waste (WG) in the state of Paraná, identifying the main potential of the use of plaster residue in relation to reverse logistics. At the same time, the diagnosis of CDW and GW management was carried out in the 20 largest municipalities that generate waste in the State of Paraná, through the application of self-filled questionnaires.The CDW of Cascavel was characterized according to NBR 10.004 and the WG, was characterized as physicochemical properties (Chemical Composition, Specific Mass, Unit Mass, Particle Size Analysis, Thermogravimetric Analysis, and Water Absorption). Through a bibliographical survey was made the compilation of the main studies related to the use / recycling of the GW. Based on the survey on the potential receptors for WG in the State of Paraná, which could absorb GW as feedstock, was elaborated flows for the reverse logistics of gypsum, made the economic analysis for the use of WG as raw material in the production of cement. Based on the study, the CDW management landscape in the state of Paraná leads to the conclusion that the management of CDW is still a challenge in the state. In most municipalities only a portion of the CDW are collected and destined to adequate disposal units, and CDW recycling is incipient and the policies aimed at the management of CDW are in the process of maturing. There is no separation of GW and reverse logistics followed by reuse / recycling is practically non-existent. The CDW sampling generated in the municipality of Cascavel showed an CWD composition similar to most Brazilian municipalities (Class A 86.29%, Class B 12.36%, Class C 0.29% and Class D 1.05%).In relation to the characterization of the WG, the results indicate that have physicochemical properties compatible with the natural Gypsum, which can be reused as construction material from simple treatment processes. Among the main forms of reuse / recycling identified in the present study, the use as in the cement industry is the best alternative at the moment, since the cement plants show interest in the use of this material and are located in regions close to the generation sites studied here. At the same time, this alternative has a certain consumer market (cement industries) that demands large volumes. Economic viability studies have demonstrated that the WG processing received in Cascavel for use in cement manufacturing may be a viable alternative.However, there is a need for regularity in the send of WG loads to cement plants, with a guarantee of supply of this material, in volume and periodicity of shipment. In this sense, larger volumes being received and processed could dilute costs and reduce the price of the tonne of recycled gypsum, which demonstrates the need to work with regions as well as consider the alternative of local reuse.