Nick Cheffins, Peakhill Associates

1. HOW WILL THE DIGESTATE MARKET DEVELOP?
CHAIR:
DR DAVID TOMPKINS, WRAP
PANEL:
ANNA BECVAR, EARTHCARE TECHNICAL LTD
DR NICK CHEFFINS, PEAKHILL ASSOCIATES LTD
DR PAUL GIBBS, 4R GROUP LTD
MATT TAYLOR, ADAS UK LTD

2. Potential use of AD digestate fibre in Commercial Horticulture
Feasibility studies on the use of AD Digestate fibre as a peat replacement

5. Components of the peat replacement test media
used in the Hardy Nursery Stock trial
Supplier Feedstock Process type Separation
technology
A Potato wastes Mesophyllic continuous
flow
Centrifuge
B Source-segregated
Biowaste producing SSB
Digestate
Mesophyllic continuous
flow
Flotation skimmer
C Maize Based energy
crops producing MB
Digestate
Mesophyllic continuous
flow
Screw press
CGW Composted non woody
and woody Green
Waste (CGW)
Open windrow aerobic
composting
Screened to 10mm

6. 0.00
20.00
40.00
60.00
80.00
100.00
120.00
T = 0
T = 4
T = 7
T = 11
g
Pelargonium Fwt -g
Tr1
Tr2
Tr3
Tr4
Tr5
0.0
5.0
10.0
15.0
20.0
25.0
30.0
T=0
T=4
T=7
T=11
sgi
Pelargonium SGI
Tr1
Tr2
Tr3
Tr4
Tr5
Tr1 = Commercial peat media
Tr2 = Commercial peat free media
Tr3= 50:50 Potato waste AD Fibre:CGW
Tr4= 50:50 SSB AD Fibre:CGW
Tr5= 50:50 MB AD Fibre:CGW

7. 0
5
10
15
20
25
30
35
40
45
1
2
3
4
g
HeucheraFwt-g
Tr1
Tr2
Tr3
Tr4
Tr5
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
T=0
T=4
T=7
T=11
sgi
Heuchera SGI
Tr1
Tr2
Tr3
Tr4
Tr5
Tr1 = Commercial peat media
Tr2 = Commercial peat free media
Tr3= 50:50 Potato waste AD Fibre:CGW
Tr4= 50:50 SSB AD Fibre:CGW
Tr5= 50:50 MB AD Fibre:CGW

8. T = 4 weeks
T = 7 weeks

11. This study is part of a WRAP programme of feasibility studies into the potential for AD Digestate in Commercial Horticulturenick.cheffins@peakhill- associates.co.uk

12. A footnote to the future(?)