Technology & Technology Transfer Techniques for Low-Cost Sustainable Ecomaterials for Reconstruction

Transcription

1 10 th East Asia Pacific Conference on Structural Engineering & Construction Mini-Symposium: Hazard Mitigation and Infrastructure Renewal Technology & Technology Transfer Techniques for Low-Cost Sustainable Ecomaterials for Reconstruction Robert Day & Fernando Martirena University of Calgary & Universidad Central de Las Villas

2 SHELTER AS AN URGENT NEED IN THE DEVELOPING WORLD Large social sectors cannot access decent housing and municipal facilities... millions of people live in shacks...

3 VULNERABILITY AGAINST NATURAL CATASTROPHES The needy are the most susceptible to: Tsunamis, Earthquakes, Hurricanes Floods

4 The Problem The Problem Many building materials use a lot of Portland cement Portland cement manufacture consumes much energy & releases greenhouse gases Thus, building materials cost a lot; putting satisfactory housing and house-rebuilding beyond the reach of many people, NGOs and governments

5 Some ashes from natural and waste materials can be made to be reactive Use them to replace some or all of the Portland cement A Solution

6 Why Waste Materials for Rebuilding lower cost -- $ go further for reconstruction potentially better quality, more resistant to storms, earthquakes, etc. rebuild at lower cost and with revised methods to produce safer houses Development $$ go further reduces impact on natural resources coral reefs use of waste materials useful energy production

7 Industrial Types of Waste Ashes fly ash coal fired generating stations blast furnace slag steel manufacture Natural volcanic ashes ash from agricultural waste incineration Urban straw, wheat, tea, sugar cane, rice, etc., etc. municipal solid wastes

8 Worldwide Deposits of Volcanic Ashes and other Reactive Surface Deposits

9 Traditional Building Materials Raw ingredients Chemical Reaction Products Result CALCIUM SILICATES in PORTLAND CEMENT + WATER STONE (AGGREGATE) TIME CALCIUM-SILICATE HYDRATE (THE CEMENT) CALCIUM HYDROXIDE (LIME) CONCRETE BLOCK BRICK ROOF TILE ETC. SAND

10 Building Materials From Wastes Raw ingredients Chemical Reaction Products Result CALCIUM SILICATES in PORTLAND CEMENT + reduced amount TIME CALCIUM-SILICATE HYDRATE (THE CEMENT) LOWER COST MORE SUSTAINABLE CONCRETE BLOCK BRICK ROOF TILE ETC. WATER STONE (AGGREGATE) SAND WASTE ASH CALCIUM HYDROXIDE (LIME) + SILICATES IN WASTE ASH TIME MORE CALCIUM-SILICATE HYDRATE (THE CEMENT)

11 Challenges Ashes can be highly variable in reactivity because of variations in combustion / cooling Chemical activators Production process has to be simple local communities Social issues acceptance in communities overcome status symbol of Portland cement Gender

12 WHAT IS NEEDED FOR SHELTER? Labor cost can take up to 40% of the construction budget... COMMUNITY PARTICIPATION as a means to decrease construction costs...

13 Methodology establish centres of knowledge and application excellence within each country for building materials especially ecomaterials and housing establish ecomaterials workshops (entrepreneurships) that have excellent quality control and management reach out to the community through extensive advertising and by building demonstration houses and housing projects using the ecomaterials Presence of a strong NGO establishes a strong connection between Centres of Excellence (Universities) and the Workshops & Community

14 HOW TO ORGANIZE A LOW COST HOUSING PROJECT? MCR tiles Manufacture of ecomaterials Bricks House construction Building materials supply Pozzolan cement CP-40 SALE Blocks, pavement bricks Building materials supply Paid labor SALE Self-help Housing delivery Local BM Market Other housing projects Social projects Alternative financing schemes Low sale prices CROSS FINANCING!! Housing market Higher sale prices Traditional bank loan schemes It must be commercially viable, and socially and ecologically sustainable...

15 Technical development centred in Cuba Economic Development focused around a strong participative NGO Latin America Case Study

16 THE ECOMATERIALS WORKSHOP Biomass Limestone Clay, admixture Pozzolan, lime OPC, aggregates OPC, aggregates OPC, aggregate, steel RAW MATERIALS Densification (Briquetting) Burning (Limekiln) Burning (Brick kiln) Grinding Ball mill MB- 600) Compacting (block machine) vibrating (vib table) Pre-stressing TECHNOLOGY + KNOW-HOW Solid Fuel Block Cal Hidratada LPB CP-40 BASIC PRODUCTS Lime mortar Fired clay brick Masonry mortar Hollow concrete block Pavement brick Shells MCR tile Floor tiles Support structure, roof and floors FINAL PRODUCTS LOCAL ECOMATERIAL MARKET SOCIAL HOUSING PROGRAMS COMMERCIAL HOUSING PROGRAMS HOUSING RENOVATION AND REPAIR THE PRODUCTION GOES TO Production wastes are recycled as raw materials for other productions...

17 WORKSHOPS IN OPERATION CUBA

18 WORKSHOPS IN OPERATION REST OF THE WORLD

19 Sugar Cane Bagasse

20 THE PROCESS of CAPACITY BUILDING Academic financing scholarships Universities in the developed world Fundamental research Market commercial applications Cuban University Applied R&D Consulting Technology development ECOSUR coordination Social projects pilot scale applications Legend Machine manufacture commercial contracts Partnership Flow of resources Development agencies financing Network of Centres of Excellence in Satellite Countries

21 ALTERNATIVES FOR POZZOLANS IN CUBA 3 The heat generated in the combustion can be recovered and used when burning occurs at temperatures over 700 o C.. Ashes from the solid fuel block (Sugar cane straw and clay mixed and burnt at 900 o C) 2 1 Ashes burnt without control (Sugar cane bagasse and straw) Ashes burnt under control in incinerators (Sugar cane straw burnt at 700 o C)

22 The SFB is made out of clay and biomass (rice husk, sugar cane straw, recycled paper, etc.)... The ratio clay/biomass ranges from 20/80% (wt.)... THE SOLID FUEL BLOCK

23 THE SOLID FUEL BLOCK SOLID FUEL BLOCK Lime Kiln Lime burning Brick Kiln Brick firing Cooking stove Food cooking Combustion device Quicklime Production Ash pozzolana Fired clay bricks Food Primary Products Lime-pozzolana cement End Products Small Format Precast Concrete Elements The SFB is an excellent fuel whose ashes are likely reactive...

24 USE OF LIME-POZZOLAN MIXTURES IN THE MANUFACTURE OF HOLLOW CONCRETE BLOCKS The concrete used in the manufacture of hollow concrete shows a strength in the range 9-12 MPa and has a dry consistency it does not require superplasticizers

25 Manufacture Lime-Pozzolan Cement (zero Portland cement) intergrinding 70% by mass of ash with 30% by mass of hydrated lime found to be optimum Lower costs for some applications can be achieved by using only 20% lime some grinding to produce a finer, more reactive powder is usually necessary grinding times of minutes, minimize energy requirement, have been found to be adequate

26 Building Units most Lime-Pozzolan cements made from biomass are slow reacting for practical manufacture of units some Portland cement or chemical activator or both blocks can be cured in a warm, moist environment in hot countries, placement in plastic tents provides good curing conditions

27 Use of Chemical Activators ACTIVATOR 1 ACTIVATOR 2 ACTIVATOR 3 ACTIVATOR 4

28 IMPACTS OF THE TECHNOLOGY DEVELOPED Scientific (Full cycle research) Economic (Resource savings/technology trading/project financing) Social (Job creation) (Wealth generation) Ecologic (Green house gases reduction/waste recycling ) The technology transfer is done as a South to South endeavor...

29 As Community Leaders, Women play a very active role IMPACT: GENDER

30 IMPACT: OPTIMAL USE OF RESOURCES

31 IMPACT: LOAN SCHEMES Total payment Interest $14, $14, $12, $12, $10, $10, $US dollars $8, $6, Family 1 Family 2 Family 3 $US dollars $8, $6, Family 1 Family 2 Family 3 $4, $4, $2, $2, $0.00 1st year 5th year 10th year $0.00 1st year 5th year 10th year Cost of house Upfront Mortgage Years Interest Monthly paym Family 1 $9, $4, $5, % $ Family 2 $9, $4, $5, % $77.63 Family 3 $9, $4, $5, % $ Alternative financing schemes have been set into practice to benefit those families which do not qualify for traditional bank loans...

32 IMPACT: BUILDING CAPACITY Establishment of Local Centres of Excellence promotes the occurrence of Critical Mass Hundreds of persons have been trained in the manufacture and use of ecomaterials...

33 IMPACT: HOUSE UPGRADING

34 IMPACT: JOB OPPORTUNITIES

35 IMPACT: IMPROVING DISASTER VULNERABILITY

36 IMPACT. MASS SOLUTIONS The project has provided decent housing to thousands of people in Latin America

37 IMPACT. MARKET POTENTIAL MCR 10,000 s.q.m. Roof in Dhaka, Bangladesh New markets for the ecomaterials are envisioned for the forthcoming years

38 Impact: North American Market

39 Thank you For additional information: Robert Day