Presentation on theme: "SOLID WASTE MANAGEMENT THROUGH GEOPOLYMER TECHNOLOGY FOR THE DEVELOPMENT OF VALUE ADDED PRODUCTS Prof. (Dr.) N. R. Bose Gandhi Institute of Engineering."— Presentation transcript:
SOLID WASTE MANAGEMENT THROUGH GEOPOLYMER TECHNOLOGY FOR THE DEVELOPMENT OF VALUE ADDED PRODUCTS Prof. (Dr.) N. R. Bose Gandhi Institute of Engineering & Technology, Gunupur, Rayagada, Orissa, India
INTRODUCTION 1.Name : DR. NRIPATI RANJAN BOSE 2.Qualifications : B. Sc. ; B. Tech. (Chemical) ; M.Tech. (Chemical) ; Ph.D.(Tech.) in Polymer Science & Technology 3. Nationality : Indian 4. Past position : Principal Scientist at Central Glass & Ceramic Research Institute under Council of Scientific & Industrial Research (C.S.I.R.), Govt. of India 5. Work Experience : (a) 8 years in Plastics, Paints, Fibreglass Reinforced Plastics (FRP) and Plywood Industries (b) 24 years as Scientist for R & D work having following output : * Publications in International Journals : 25 * Patents : 1 International ; 5 Indian * Presented Papers in International Conferences : 15 * Technical Know-How Transferred to Industries : 2 * -Guided Ph.D. students : 2 6.Present Activities : (a) Director of New Era Polyset Engineering Pvt. Ltd., Kolkata, India (b) Consultant of Sols 4 All Consultants, Kolkata, India (c) Expert for the project “Development of Bullet Resistant Armour Panels “ at Central Glass & Ceramic Research Institute, Kolkata under CSIR, Govt. of India (d) Contract research, Product Development and Commercial Utilisation 7.Author of two Chapters : Books published by Woodhead Publications, U.K. 8.Membership with Professional Scientific bodies : (a) Institute of Materials, U.K., (b) Indian Concrete institute (c) Indian Plastics institute, (d) Indian Science Congress Association
Serious Pollution Hazards Rapid urbanization -----Building industries -----Uses of Diesel & Petrol -----Generation of Solid Waste -----Increase of Population Industrialization -----Increase of Cement Industries -----Generation of Solid Waste such as : * Fly Ash * GGBS * Rice Husk Ash * Red Mud * Food Waste * Wood Dust * Hospital Waste * Radioactive Waste etc. *
Present Scenario(1) 1.One ton cement production require 2 tons of shale and limestone ---- releases 0.87 ton Co 2, 3 Kg. NO and airborne particulate matter that is harmful to the respiratory tract when inhaled. 2.Thermal Power Stations, and Steel Industries are using coal and creating environmental pollution by their by-products (a) Fly Ash (FA), and (b) Ground Granulated Blast Furnace Slag GGBS) 3.Aluminium Industries creating environmental pollution by their by-products ------Red Mud 4. Uranium Industries, Nuclear Power Plants & Atomic Reactors are generating toxic radioactive waste 5.Chemical Industries are creating (a) liquid waste which are polluting river & underground water, (b) Toxic gases from chimneys polluting air in the environment
Present Scenario(2) 6. Food Industries are generating solid & liquid waste 7. Plywood Industries and saw mills are generating wood dust --- creating air pollution 8. Ceramic processing industries are polluting air by releasing carbon dioxide from chimneys 9. Bricks manufacturing industries are polluting air by releasing carbon dioxide from chimneys 10. Surface coating industries are creating air pollution by using solvent based paint and coating resins
Recent trends for controlling pollution Total Quality Management of production processes and to ensure zero pollution hazard in the environment Development of green building materials Production of Geopolymer binder from solid waste Conversion of chimney gases into products or absorpsion of chimney gasses in suitable chemical solution by scrubbers Production of fire resistant composite panels by using Waste-Waste System Encapsulation of radioactive waste & other toxic materials in Geopolymer binder and to produce composite panels
Major industrial wastes in India Fly ash ------------------------- 100 million tonnes Granulated blast furnace slag--- 12 million tonnes Rice husk ash --------Huge quantity Red mud ------------- 4 million tonnes
Composition of waste materials These waste materials contain SiO2 and Al2O3 along with Fe2O3, CaO, MgO, MnO, etc, and have immense potential as man made raw materials for the production of geopolymeric cement and binder.
Fundamentals of Geopolymer Geopolymer is essentially a mineral chemical compound or mixture of compounds consisting of repeating units, for example silico-oxide (-Si-O-Si-O-), silico-aluminate (-Si- O-Al-O-), ferro-silico-aluminate (-Fe-O-Si-O-Al- O-) or alumino-phosphate (-Al-O-P-O-)---------- -----------------------created through a process of geopolymerization
Applications of Geopolymer Geopolymers are new materials for : Fire- and heat-resistant coatings Adhesives & medicinal applications High-temperature ceramics New binders for fire-resistant fiber composites Toxic and radioactive waste encapsulation New cements for concrete.
Methods of making geopolymers(1) A novel three-dimensional mineral polymers named as geopolymers are designated in IUPAC International Symposium on Macromolecules, Stockholm in 1976, Topic III; and PACTEC IV, 1979, Society of Plastic Engineers, USA, preprint page 151. These mineral polymers are called polysialates, and have this empirical formula : Mn[(-Si-O2)z -Al-O2-]n, wH2O Wherein z is 1,2 or 3; M is a monovalent cation such as potassium or sodium, and n is the degree of polycondensation. When z is 2, the polysialate has the formula : Mn(-Si-O-Al-O- Si-O -)n,,wH2O O O O and is called poly(sialate-siloxo) or PSS for short. These new polymers are of the PSS type where M is sodium or a mixture of sodium and potassium. In the latter case, the polymer is called (sodium, potassium) poly(sialate-siloxo) or (Na, K) - PSS. The chemical formula of (Na, K) - PSS may be written as : (Na, K)n (-Si-O-Al-O- Si-O -)n,,wH2O O O O
Method of making geopolymers(2) The method of making (Na, K) - PSS comprises preparing a sodium silico-aluminate / potassium silico-aluminate and water mixture where the composition of the reactant mixture, in terms of oxide-mole ratios, falls within the ranges shown in Table 1 below. Table1. Oxide-Mole-Ratios of the Reactant Mixture _____________________________________ (Na2O, K2O) / SiO2 0.20 to 0.28 SiO2 / Al 2O3 3.50 to 4.50 H2O / (Na2O, K2O) 15.00 to 17.50 (Na2O, K2O) / Al 2O3 0.80 to 1.20 ______________________________________
Geopolymer binder from Fly Ash ____________________________________________________________ Amount of component (grams) Wt % ____________________________________________________________ 50 % Sodium Hydroxide Solution 741 14.82 37.60 % Sodium Silicate Solution 702 14.03 Class F Fly Ash 3557 71.15 Additional water Nil Nil ___________________________________________________________
Preparation of specimens & test results Two samples of Fly Ash based GP binder mixture of are casted in a mould and heat cured at 90 oC for 18 hours, and then removed to ambient conditions. After two days, the specimens are prepared in accordance with ASTM C-192 and ASTM C-617 for measurement of compressive strength. The specimens are then tested for compressive strength according to ASTM C-39. ________________________________________________________ Preparation of specimens & test results ________________________________________________________ Example No. Curing Curing Compressive Temp. (oC) Time (hrs.) Strength (MPa) ________________________________________________________ 1 90 18 86.80 2 90 18 77.00 _________________________________________________________ There is an enormous scope for the development of various value added products by reinforcing fibres and fillers in Fly Ash based geopolymer binder mixture. Notable value added products such as bricks, pavement tiles, fire resistant panels etc. can be manufactured
GGBS based Geopolymers Conventional iron manufactures leaves slag as a crystalline stone that is dispersed as waste or used as road-railway-track base material in replacement of crushed basalt or granite Such crystalline structure does not provide geopolymeric reactivity. Only those slags that are glassy and have been prevented from crystallization can be used as geopolymer precursor The blast furnace slag is a molten material that is formed from the smelting of the siliceous gangue found in iron core, the residue of coke combustion, the limestone and other added ingredients. Its temperature is in the range between 1400o and 1600oC and is close to that of the molten iron.
Contd. The slag becomes suitable for geopolymeric reaction when quenched from the melt. It is called granulated slag or ground granulated blast furnace slag (GGBS) The glassy material is obtained either poured into pits filled with water or by high-pressure water jets at the blast furnace, when it flows out of the spout A modern system of granulation, the pelletizer, has been developed in Canada (Margesson ) and in England during the year 1971. From a geopolymeric chemistry point of view, gehlenite [Ca-poly(alumino-sialate) based blast furnace slag is the reactive molecule with effective potential as geopolymeric precursor
Composition of gehlenite based GGBS The average composition of gehlenite based blast furnace slag with the main oxides of different countries is given in the following Table ____________________________________________________________ Slag origin SiO2 % Al 2O3 % CaO % MgO % ____________________________________________________________ Australia 35.00 11.50 41.50 6-12 USA 32.83 11.59 41.43 8.03 Germany 33.27 10.90 44.77 5.27 Czeh. Rep. 36.18 9.61 35.39 14.49 Canada 35.30 9.90 34.70 14.60 France 35.00 12.20 43.20 8.10 ____________________________________________________________
Mole ratios of oxides For making GGBS based geopolymer composite For making GGBS based geopolymer composite, the following oxide mole ratios are optimized at the laboratory of Prof. Joseph Davidovits at Saint Quentin, France. The mole ratios of oxides are given in the following Table Mole ratios of oxides _____________________________________________ Oxides Mole-ratio _____________________________________________ M2O / SiO2 : 0.21 to 0.36 SiO2 / Al 2O3 : 3.00 to 4.12 H2O / M2O : 12 to 20 M2O / Al 2O3 : 0.60 to 1.36 ______________________________________________ where M2O represents either Na2O, or K2O, or the mixture of Na2O and K2O. To 100g of the oxide mixture given in the above Table about 15g to 26g of a finely ground blast furnace slag is used. High early compressive strength of more than 250 MPa is obtained by using this mineral polymer composition with filler and /or fibres.
Rice husk ash based geopolymers Rice milling generates a by-product known as husk. This surrounds the paddy grain. During the milling about 78 % of weight is received as rice and bran. The remaining 22 % is the husk The latter is used as fuel in the rice mills to generate steam. The husk contains about 75 % organic volatile matter and 25 % of the weight is converted into ash during the firing process, known as rice husk ash Rice husk ash in turn contains around 85 % - 90 % amorphous silica SiO2. For every 1000 kg. of paddy milled, about 220 Kg. (22 %) husk is produced, and when the husk is burnt in the boilers, about 55 Kg. (25 %) of rice husk ash is generated The most profitable use of silica fume and rice husk ash is in the cement and concrete industries Geopolymer binder is made by mixing rice husk ash and silica fumes with NaOH or KOH solution. For the development of geopolymer concrete Al(OH)3 powder is used up to 10 % as activator and 1 % Boric acid as stabilizer at 115o C The compressive strength of rice husk ash mortar is 20.0 MPa High compressive strength value added products can also be developed by incorporating fibres in this geopolymer cement binder.
Geopolymer Technology Developed By Prof. Davidovids, Founder of Geopolymer Institute, Saint Quentin, France (Paper presented in July, 2013)
New Avenues For The Development of High Value Composite Materials Fibre Reinforced Geopolymer Cement Based Composite Materials 1. Fire Resistant Structural Panels 2. Insulated Foamed Roof Panels 3. Chemical Resistant Panels 4. Door Panels 5. Bricks 6. Tiles
Importance of Geopolymer PART-1 Geopolymer has great potential to reduce the environmental pollution in two ways : 1 Fulfillment of the demand of portland cement by using Geopolymer cement without going for new cement industries 2. Fruitful utilisation of waste materials such as FA and GGBS for the production of good quality Geopolymer cement by chemical transformation of Al and Si
Importance of Geopolymer PART-2 Properties of GPCC mixes : 1.Compressive strength in 24 hours : 25-35 MPa 2.Compressive strength in 28 days : 60-70 MPa 3.Modulus of Elasticity : Marginally lower than cement concrete 4.High stiffness 5.Acid, Alkali, Heat and Fire Resistant 6.Bond Strength with Steel is higher than cement concrete ( IS : 456-2000 ) 7.Durability as per ASTM 1202 C : Better protection of steel as compared to cement concrete
Importance of Geopolymer PART-3 Geopolymer Cement Concrete (GPCC) materials are inorganic polymer composites using Geopolymer Cement prepared by alkali activation of industrial aluminosilicate waste materials such as FA & GGBS
Proposed Design of Fire Resistant Composite Panels 1.Impregnation of Ceramic Blanket with Geopolymer Cement Slurry Blended with Water Settable Polyester Resin + Redox Catalyst + SBR Latex + Fillers + Water as required : Formed into Prepreg Layers 2.Assembly of Multiple Prepreg Layers as per desired thickness in between two Aluminium Metal Sheets 3, Pressing in Cold Hydraulic Press The above design is based on ESTERCRETE USES : * Blast Resistant Structural Panels for Defense Sector * Bridge Decks & Industrial Flooring Compressive Strength : More than Ordinary Concrete
Proposed Design of Insulated Foamed Roof Panels 1. Geopolymer Cement Slurry + Water Settable Phenolic Resole Resin + SBR Latex + PTSA Catalyst + Sand + Stone aggregates + Super- plasticizer + Polypropylene Fibre + Water as required 2.Polyurethane Foam System (Part A & Part B) 3.Silicone Rubber Mould 4.Anti Sticking Silicone Spray 5.Compacting Box System to Hold Silicone Rubber Mould Production Process : After Mixing Part A & Part B of item No. 2 then add Item No. 1 ------------- -After mixing -------------pour into the closed Mould properly coated with anti sticking Silicone Spray
Proposed Design of Chemical Resistant Floor 1.Water Settable Isophthalic Polyester Resin 2.Geopolymer Slurry 3.Redox Catalyst System 4.SBR Latex 5.Sand 6.Stone (6-8 mm) Aggregates 7.Polypropylene Fibre 8.Water as required Application : After Mixing item Nos. 1-8 in a Gear Mixer it is to be pumped through Hose Pipe inside the Framed workplace. Curing for 12 hours will develop high compressive strength.
Proposed Design For Doors and Windows 1.Fibre Reinforced Plastics (FRP) Casings as per size of the doors and windows 2. Geopolymer Slurry + PU Foam System + Water Settable Polyester Resin + Redox Catalyst + SBR Latex + Polypropylene Fibre + Superplasticizer + Water as required Production : 1. Mixing all ingredients of item No. 2 and then injection into individual FRP casings 2. Curing time : 12 hours
PROPER SOLUTION 1. Production of Geopolymer for gainful utilisation of FA and GGBS and to save the environment by reducing stockpiles 2. Use of Geopolymer cement as a right substitute of Portland Cement for the production of value added composite products
Possibilities for New Research Projects 1.Nano fibre development from Geopolymer Gel by using Electrospinning Equipment 2.Anti Rust and High Heat Resistant Inorganic Waterbase Geopolymer-Zinc Rich Coating for Cathodic Protection of Steel 3.Development of Advanced Nano Ceramic Composites Based on Geopolymer Gel
Conclusion Geopolymer concrete shows significant potential to be a material for the future because it is not only environmentally friendly but also possesses excellent mechanical properties Recommendations on use of geopolymer concrete technology in practical applications such as precast concrete products and waste encapsulation need to be developed * Geopolymeric binder can be utilized for fire resistant panels and coatings on different substrates, advanced nano-ceramic composites, development of foam concrete, encapsulation of radioactive waste, low cost bricks etc.
Conclusion Because of lower internal energy (almost 20% to 30 % less) and lower CO2 emission contents of ingredients of geopolymer based composites compared to those of conventional Portland cement concretes, the new composites can be considered to be more eco-friendly and hence their utility in practical applications needs to be developed and encouraged. Geopolymer based cement is having high early strength and high setting characteristics. These characteristics of geopolymer cement based products are ideal for patching or resurfacing of highways and airport runways.
Conclusion * It is possible to utilize various solid waste materials ( FA, GGBS, RHA and Red Mud ) through Geopolymer Chemistry for the development of binder and cement * It is poosible to formulate mixing compound with semi solid waste materials, geopolymer binder and water soluble polymer for the development of high value products
Future course of action * To involve myself in collaborative or sponsored Research Project To work jointly with suitable organization for the development of new products by utilizing any kind of waste materials To save the environment through techno-commercial waste management To substitute prefabricated cement based concrete with geopolymer based concrete * To develop blast resistant composite panels for defence sectors --------------- Thank you all ---------------