Research activities of the Department of Metallurgical and Materials Engineering related to waste treatment

Transcription

1 University of São Paulo Polytechnic School Dept. of Metallurgical and Materials Engineering Research activities of the Department of Metallurgical and Materials Engineering related to waste treatment Samuel M. Toffoli May 26,

2 Summary Introduction Laboratories Researchers Previous work Current work 2

3 : Public University (State of São Paulo) Escola Politécnica Introduction 3

4 Introduction Department of Metallurgical and Materials Engineering (Escola Politécnica): Ø Twenty-four faculty members (all PhD s): metallurgy, ceramics, polymers, inorganic raw-materials, thin films, clay technology, and carbon composites. Ø Metallurgical Engineering: 75 years old Ø Materials Enginering: 20 years old Ø Graduate students: ; Undergraduates: 40 every year 4

5 Introduction Tradition in conducting research work in the field of recycling materials since early 1990 s Focus on: Commodity and engineering polymers Polymer matrix composites Glass technology Traditional ceramics (pottery, tiles, glass, etc.) Besides recycling materials, a few lines dedicated to: Improving degradability of polymers Clay technology (from traditional ceramics to nano-fillers) Immobilization of toxic wastes in clays and cements 5

6 Summary Introduction Laboratories Researchers Previous work Current work 6

7 Laboratories Ceramics & Plastics: v Formerly: LMPSol Laboratory of Particulate Raw- Materials and Non-Metallic Solids v Current: LPSS Laboratory of Non-Metallic Materials Prof. Pérsio de Souza Santos Polymers: v Polymer Materials Processing and Rheology 7

8 Personnel Current permanent personnel Hélio Wiebeck: Ph.D. (Chemical Engineering, USP, 1991) Samuel M. Toffoli: Ph.D. (Ceramic Science and Engineering - Rutgers University, USA, 1996) Antonio Carlos V. Coelho: Ph.D. (Sciences Naturelles Appliquées - Université Catholique de Louvain, 1991) Francisco R. Valenzuela-Diaz: Ph.D. (Chemical Engineering, USP, 1994) Ticiane Sanches Valera: Ph.D. (Chemical Engineering, USP, 2005) 8

9 Summary Introduction Laboratories Researchers Previous work Current work 9

10 Previous Work Projects that have been discontinued (end of the project or end of the funding) Use of rice hull ash (RHA) in polypropylene: Brazil has huge amounts of RHA: environment problem RHA may be used as a replacement for talc or kaolin, as an inorganic filler in the reinforcement of nylon (polyamide-6) Substitution of the traditional filler by RHA yielded similar mechanical and thermal properties (for filler contents up to 30 wt%) Limitation: color possible (due to variable iron content) 10

11 Previous Work Projects that have been discontinued (end of the project or end of the funding) Formation of people working in landfills, collecting recyclables: Underpriviliged people from the city of São Bernardo do Campo (metropolitan area of São Paulo) Classes on the very basics of materials (~100 persons) Organizing a cooperative (in a city s warehouse) Training in separating and classifying urban colectable materials, aggregating value and selling for better profit 11

12 Previous Work Projects that have been discontinued (end of the project or end of the funding) Use of glass and PVB from recycling postconsumer windshields: Coarse glass is easilly returned to re-melt. Fine waste glass unwanted by glass factories PVB (polyvinyl butyral) is thermoplastic, expansive, but contaminated with glass particles Several research lines were conducted: 12

13 Previous Work Projects that have been discontinued (end of the project or end of the funding) Use of glass and PVB from recycling postconsumer windshields 1: Use of the particulate glass in wood floor varnishes for high traffic applications Used in compositions already containing aluminum oxide Improved abrasion resistance for filler contents of 10 wt % (5% glass particles + 5% Al 2 O 3 ) 13

14 Previous Work Projects that have been discontinued (end of the project or end of the funding) Use of glass and PVB from recycling postconsumer windshields 2: Simultaneous use of the glass and the PVB in PA-6 (nylon) matrices Recycled glass particles replace glass microspheres. PVB acts as a toughening agent for PA-6 Very good toughness for up to 30 wt% of PVB and 10 wt% of glass, although strength decreased Brazilian patent 14

15 Previous Work Projects that have been discontinued (end of the project or end of the funding) Use of glass and PVB from recycling postconsumer windshields 3: Use of the glass particles in a traditional ceramic roof tile composition Tested in amounts from 5 to 25 wt%, in two particle size distributions At the high processing temperatures, the main rawmaterial, a common clay, sinterizes, and the glass melts, reducing total porosity and improving strength 15

16 Summary Introduction Laboratories Researchers Previous work Current work 16

17 Current Work Main active research projects: Use of glass and polymeric components from postconsumer computer LCD monitors Two approaches: 1. Disassembling the monitor and using up to 10 wt% of the ground screen, as-is (containing at least 10% of polymers, etc.), in nylon-6: mechanical properties comparable to the ones obtained using (uncoated) microspheres as fillers 2. Up to 30 wt% of the ground screen as a filler. Polymer matrix: the frame of the LCD screen (blend PC-ABS). In progress 17

18 Current Work Main active research projects: Ordinary glasses prepared with chromium-rich ashes from the incineration of tannery sludge Brazil is the second largest world producer of bovine leather. The tanning process generates great amounts of chromium-containing sludges (Cr 6+ is carcinogenic) Chromium (III) is regularly used in the coloration of commercial green glass for beer and wine containers The stability of the chromium ions during calcination and their effects on the glass were studied To be also investigated: the use of the same chromiumrich ashes in the fabrication of chromium refractories 18

19 Main active research projects: Use of basalt rock fines Current Work In the production of basalt crushed stone (for concretes, e.g.), the fines are rejected The melting of basalt fines result in a lustrous black silicate glass Adequate high-temperature thermal treatment of the glass allows the growth of crystalline phases in the glass, resulting in a very abrasion-resistant glass-ceramic Use: coating of tubes, pipes and bins for mineral ores, submitted to high abrasion and/or chemical attack 19

20 Current Work Main active research projects: Thermoplastic corn starch (TPS) and recycled-pp blends for better degradable packaging Up to 50 wt% of TPS mixed with post-consumer polypropylene (PP) Results so far indicated that tensile and impact strength of some compositions are similar to the ones for virgin PP On the other hand, TPS is easily biodegradable, whereas PP is not (in a composting environment, TPS is decomposed within 6 months) 20

21 Closing Remarks Today s main financing sources: public agencies or companies (CNPq, FAPESP, Sabesp, etc.). Little help from private companies or groups Researchers willing to develop joint projects with Brazilian and/or international partners Collaboration most wanted because all the basic laboratory infra-structure is available, but access to high-end techniques is more difficult, and... 21

22 Closing Remarks Already available: Expertise: professors & research background Hi-level human resources: graduate students (M.Sci. and Dr.), post-doc researchers, and technicians Strong demand for technical solutions: Brazil is a developing country Política Nacional de Resíduos Sólidos (PNRS): National Policy on Solid Wastes (2010). Federal law that establishes shared responsabilities on the wastes and reverse logistics 22

23 University of São Paulo Polytechnic School Dept. of Metallurgical and Materials Engineering Research activities of the Department of Metallurgical and Materials Engineering related to waste treatment Thank you!! Samuel M. Toffoli 23