SLIDE 1 An overview of fibre crop cultivation and multi-product value chains for post-mining industrial development
CENTRE FOR BIOPROCESS ENGINEERING RESEARCH
STL Harrison, S Rumjeet, X Mabasa, M Solomon, B Verster
MINERALS TO METALS INITIATIVE
JL Broadhurst, T Chimbganda, G Hangone
SLIDE 2
Over 5900 abandoned mines in SA Over 300, 000 job losses since 1987 Significant loss of biodiversity
Problem lem statem emen ent
SLIDE 3
Fib Fibre c crop p po potent ential
Exploring the potential of fibrous plants
Land and remedia ediatio ion pote tenti tial Met etal reco covery pote tenti tial Fibre- deriv ived ed product ucts
SLIDE 4
fibre-rich plant
? ?
What are the downstream processing options for the recovery of value from fibre plants? Can fibre-rich plants serve the joint role of remediation of degraded mine land and fuelling of a multi-product value chain? Ke Key ques questions ns?
?
SLIDE 5
Proposed ed solut lution Explo lorin ing g the he poten entia ial o l of fibr fibrous pla plants Land d remedia ediatio ion n and m nd met etal re recovery
Phytoremediation & Phyto-mining
Metal ions
SLIDE 6 Proposed ed solut lution Explo lorin ing g the he poten entia ial o l of fibr fibrous pla plants Fib Fibre- deri derived d pr produ ducts
Fibre re Addi dditional pr produ ducts Fibre Woody tissue Chemicals Energy
fabric cordage piping
bio-char thermoplastics bio- composites pharmaceuticals shives
SLIDE 7 Conversion
Lead products
Cultivation Harvest Pre- treatment Product recovery Conversion
Plant biomass Fibrous- Part By-products Seed Water Non-Fibrous- part Fibrous- Part Additional products
Conversion
Proces essing ng Manufa fact cturin ring Manufa fact cturin ring
Biorefinery
Bioref efin iner ery
High-end by-products
Potent ntia ial l Sy Syste tem m Flo Flowshe heet
SLIDE 8 Scopi ping g study dy an and d investiga gation in n Carle letonvill ille, Rustenbu burg g & Wi Witba bank minin ing areas
Example site selection
Soil pH: 5.5 - 7 Average rainfall: 100 – 200 mm per annum Average temperature: 7 – 32 ℃
Gold Coal Platinum
Topsoil texture: Clay- sandy-loamy
SLIDE 9 Scopi ping g study dy an and d investiga gation in n Sout uth h Afric frican minin ing areas
Overview and selection of fibrous plants in South Africa
Fibre re plants ts Bast st
Leaf af
Seed eed
Fruit it
Wood
Grass ss
- Bamboo
- Non-invasive and/or indigenous
- Preferred soil type
- T
emperature tolerance
- pH tolerance
- Multi-product possibility
Crit iter eria ia f for plant nt selec lectio ion f for e example s le sites es
SLIDE 10 Fibrous plants selection
Bamboo balcooa, flax, hemp, kenaf and sisal
- Higher metal concentration ability
- Metal selectivity
- More specific metal bioconcentration sites
- Wider range of fibre and seed based products
- Grow in warmer temperatures
- Relatively easier to cultivate
Pl Plan ant selec ectio ion n crit iteri eria
SLIDE 11
Bambusa balcooa 400 – 5400 mm 9 – 35 ° C 12 – 18 tons/ha M Pb, Zn, Cr, Fe 5 – 6 years Flax Pb, Zn, Cd 450 – 750 mm 10 – 27 ° C ~ 2 tons/ha 100 days Hemp Ni, Pb, Cd, Zn, Cu 500 – 700 mm 19 – 23 ° C 2.2 – 8 tons/ha 120 days Kenaf 240 – 490 mm 15 – 27 ° C 5 – 7 tons/ha Pb, Zn, Cd 90 – 125 days Sisal 500 – 1500 mm 10 – 32 ° C 1 – 4 tons/ha Zn, Cd, Cu 2 – 4 years
SLIDE 12 Selected fibrous plants for detailed study
- A wider range of products
- Stronger fibre (tensile
strength)
Bamboo Hemp Kenaf
Hemp & Kenaf – Bast fibres Bamboo – Woody grass
SLIDE 13 Scopi ping g study dy an and d inves esti tigati tion in So n Sout uth Afri frican mi minin ing ar g areas eas
Limitations and challenges
- Metal accumulation in fibrous plants tend to
be low
- Lack of top soil, organic matter and good
microbial dynamics on degraded land
- Metals can accumulate in harvestable parts of
plants
- Product quality & safety would be an issue
- Return on investment may take long for some
- f the crops
SLIDE 14 Conversion
Lead products
Cultivation Harvest Pre- treatment Product recovery Conversion
Plant biomass Fibrous- Part By-products Seed Water Non-Fibrous- part (twigs, leaves, seeds etc) Fibrous- Part Additional products
Conversion
Proces essing ng Manufa fact cturin ring Manufa fact cturin ring
Biorefinery
Bioref efin iner ery
High-end by-products
Potent ntia ial l Sy Syste tem m Flo Flowshe heet
SLIDE 15 STEM ENTIRE PLANT SEEDS LEAVES Example: Hemp
Example - Bioethanol
Energy Fibre + Woody tissue Leaves
Medicine
Bas Bast fibr ibre pla plant proces essing ing
Bast fibre crop-to-product profile
Seeds Oil
SLIDE 16
Woody tissue Shives Construction materials Short Fibre Cordage Paper Pulp Long Fibre Bio-composites Bast Fibre Hurd & & Bast fibre stem cross-section Conventional textiles Intermediates End-products
SLIDE 17 Plant Textiles Woody tissue Stem Fibre Stem Harvest Pre- treatment Product recovery Spinning Conversion Long Short Carding Pulping Cordage Composites Paper Sorting Pulping Paper Conversion Shives Seed oil Cleaning Compression Construction materials Leaves Cleaning Conversion Whole leaves Seeds Whole seeds Fibre products Woody tissue products By- products By- products Medicine
Bast fibre multi-product flowsheet options
Spinning Conversion Carding Pulping
SLIDE 18
STEM/CULM ENTIRE PLANT BRANCHES Example - Biochar SHOOTS Energy Wood or Fibre or Pulp Household wood products Vegetable
Bam Bamboo pla plants and nd proces essing ing
Bamboo crop-to-product profile
SLIDE 19
Fibre Natural Rayon Pulp Cardboard Paper Pulp Wood OR OR Poles Wood products Bamboo culm/stem Intermediates End-products
SLIDE 20 Harvest Plant Plybamboo/ Burning Pulping Energy Board making Splitting Opti ption 1 1a Low quality stems/wastes from
Whole plant (100%) T
Culm (80%) High- end products Strand woven boards Bamboo mats Particle board Low- End or bulk products Fibre recovery Weaving Board-making High quality stems Opti ption 1 1b Opti ption 2 2a Board making Natural fibre Opti ption 2 2b MDF boards/ Poles Medium quality stems Pre-treatment Bamboo mat boards Paper pulp Opti ption 3 3a Opti ption 3 3b Opti ption 3 3c Medium
products
Bamboo multi-product processing scenarios
SLIDE 21
Lead products
Cultivation Harvest Pre- treatment Fibre- recovery
Plant Fibrous- Part Soil Water Fibre Fibrous- Part Additional products
Manufacturing
Non-fibrous parts
Potential integrated metal recovery process
Leachate (metals) (metals)
Ashing
Bio-ore
Hydrometallurgical/ pyrometallurgical extraction
Metals
Plant-synthesised nano-catalysts Manufacturing
SLIDE 22 Summar mmary o
f fi fibr bre e pr proces essing g an and pr d produ duct sel elec ectio ion
- Selection of product recovery and treatment processes is highly dependent on desired
lead and additional product types.
- All the fibre-producing plants can generate multiple products however, the range of
products differ for the different plant types.
- Exploitation of fibre-based plants and industry development will also depend on the
socio-economic and environmental drivers.
- Integrating metal recovery may limit product quality and the capability of the fibre
products.
Summary
SLIDE 23
Acknowledgements
