Kayasand RC7. Concrete Recycling, but not as you know it

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1 Kayasand RC7 Concrete Recycling, but not as you know it

2 Introducing the RC7 The only recycling equipment in the world that can economically recover fine aggregate from recycled concrete as a COMPLETE replacement for natural sand in concrete. If you have A significant source of Concrete to be recycled and there is A local requirement to include an increasingly higher proportion of recycled aggregates in concrete or; A significant cost for disposal of waste concrete Then the Kayasand RC7 offers you a unique opportunity

3 The RC7 Difference Concrete Feed RC7 Cementicious Filler by-product (can be as low as 30%) 30% High Quality Fine Aggregate High Quality Coarse Aggregate Road base Drainage granules Agriculture (lime alternative) Self levelling concrete Green Concrete

4 The RC7 Difference Unique combined crushing and separation system Cement paste and fines removal Dramatic reduction in water absorption Substantial increase in density Shaping right down to 150 microns

5 Kayasand RC7 Technology

6 Air Screen (RCAS) 4 screen decks Multi function - classification, screening and surface cleaning of the aggregate by air screen.

7 Coarse Aggregate Number of Passes Density and Water absorption Density (g/cm 3 ) JIS High grade 3 passes attain High grade Water absorption(%) 2.1 Density Virgin Numbers of passes Aggregate Water absorption 3 passes can attain more than 2.5g/cm3 density and less than 3 % water absorption. i.e. High grade required by Japanese Standards.

8 Fine Aggregate Comparison of Density and Water Absorption Density (g/cm 3 ) Density Water absorption IMPROVEMENT OF DENSITY & WATER ABSORPTION Water absorption (%) 1.8 Natural sand Unprocessed recycled sand 3 passes with air classification 0 3 passes with air classification provides high quality fine aggregate component for concrete

9 W/C ratio vs. compressive strength, replacing all of the Coarse Aggregate with RC7 recycled Aggregate 45 (7-day result) 55 (28-day result) Compressive strength (N/mm 2 ) Natural 40 Unprocessed 35 3passes Compressive strength (N/mm 2 ) Natural 50 Unprocessed 45 3passes Water/cement ratio Water/cement ratio W/C ratio and compressive strength for each sample are related as shown. The strength of unprocessed aggregate is much lower than the others The strength of the 3-passes sample is equivalent to that of natural aggregate.

10 Dry shrinkage for 3 fine aggregate samples 2500 Natural Drying shrinkage( 10-6 ) Unprocessed 3pass 2.2 times The dry shrinkage of 3 passes sample is equivalent to that of natural sand. Unprocessed aggregate has 2.2 times greater dry shrinkage than recycled sand Age of concrete (days)

11 Images of Product Feed Material Coarse Product Sand Product

12 Summary of Differences 1. The RC7 has a highly effective system to remove cement paste from recycled concrete 2. The RC7 both recovers and shapes the original aggregates 3. The RC7 products are separated into coarse and fine aggregates according to requirements, through the RCAS screen 4. The RC7 separates the minus 150 micron filler on each pass, storing the by-product as a dry material RC7 filler consists of hydrated cement, rock dust and unhydrated cement in varying proportions

13 Kayasand RC7 Economics

14 RC7 Economics (40tph feed (incl. 3 passes)) Capital Cost : Euro 2.5m Feed: 40 tph Concrete Waste Product: 10tph Coarse Agg 12tph Fine Agg 18tph Cementicious filler Capex recovery per tonne: Depreciated over 10 years 150,000 tonnes per annum Euro 1.67 per tonne of feed Or Euro 3.0 per tonne of aggregate product

15 RC7 Economics (40tph feed (incl. 3 passes)) Operating Costs Power (~Euro 0.12/kwhr) 9.5kwh per tonne feed = Euro 1.14 per tonne or 17kwh per tonne aggregate = Euro 2.04 per tonne Wear parts and maintenance Euro 3 per tonne feed or Euro 5.45 per tonne aggregate Typical Opex ~ Euro 4.14/t of Feed or Euro 7.50/t of Aggregate (Coarse + Fine)

16 Economics (includes 3 Passes) Total cost per tonne of Aggregate produced, including all opex and capital recovery = Euro 10.5 per tonne Around 45% of the output will be filler that is cementicious and has value in: Road base Self levelling concrete Agriculture (lime alternative) Drainage, underground pipe and wire surrounds (Granulated with water and cement (~5%) = pelletized product)

17 Summary There is finally a process to recover ALL of the aggregate from recycled concrete. The level of profitability of the new process depends upon: The value of the aggregate recovered The premium attached to the recycled products The ability to obtain value from the cementicious filler Alternative disposal costs

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