David Lovett, Perceptive Engineering

1. THE FUTURE OF SMALL
SCALE AD
#UKADBiogas @adbioresources
CHAIR:
SOPHIE GOODALL, HARPER ADAMS UNIVERSITY
PANEL:
DAVID LOVETT, PERCEPTIVE ENGINEERING
MICHAEL THOMPSON, RARE TECHNOLOGIES
DAVID KANER, ADVANCED ANAEROBICS
MARK CLAYTON, QUBE RENEWABLES

2. Optimisation of Small Scale Anaerobic Digesters
for improved operability
David Lovett MD Perceptive Engineering Ltd
WRAP-Perceptive Engineering Collaborative Project

3. Optimisation of Small Scale Anaerobic Digesters
Overview

4. Optimisation of Small Scale Anaerobic Digesters
The problem…..

5. Optimisation of Small Scale Anaerobic Digesters
The solution….

6. Optimisation of Small Scale Anaerobic Digesters
Minimal Operational Parameters – required for Optimisation
8/9 key parameters chosen to be representative of typical data available
Optimum
Operating
Conditions
Organic Loading Rate
Reactor Temperature
Gas Production Rate
% Methane
Anaerobic Biogasification
Potential %VSD
ORP pH
Agitator On/Off time

7. Optimisation of Small Scale Anaerobic Digesters
Solution Overview

8. Optimisation of Small Scale Anaerobic Digesters
Operational Modes of Optimisation
O There isn’t a single “Optimum” operational mode for Anaerobic Digesters. The
“Optimum” often relates balancing the overall financial operating cost with the
financial return achieved through Gate fees, biogas/Power produced and
fertiliser sales. However doing so when faced with many changing operational
constraints (feedstock availability, feedstock type, ambient temperature) and
changing economic variables such as Power tariffs, Digestate prices, is not
trivial.
O Operational Modes – defined at the onset of this study.
1. Maximise Organic Loading Rate (Ample substrate available)
2. Maximise Methane Yield (in parallel with maximising biogas flow)
3. Maximise Overall System Efficiency (Heat/Electricity balance
AD/CHP interaction)
4. Stabilisation i.e. Operate in “Tick Over” mode if little slurry
available, maintain plentiful buffer in anticipation of new variable
load.

9. Optimisation of Small Scale Anaerobic Digesters
Results….

10. Optimisation of Small Scale Anaerobic Digesters
Results….

11. WRAP, for funding this feasibility assessment
CPI, (Michelle Morrison, Len Potts and Steven Broome) for providing the operational data and
supporting the initiative
Optimisation of Small Scale Anaerobic Digesters
Acknowledgements

12. Optimisation of Small Scale Anaerobic Digesters
Vertical Digester - Statistical Monitoring
Real-Time Process Data
Digester
Real-Time Process Data
Empirical
Process Model
x1
x2
x3
.
.
xn
Compare
ŷ1
ŷ2
ŷn
ŷ3
.
.
Real-Time Process Disturbances
Process Monitor

13. 350kW Anaerobic Digester
ADvisorMVTM Dashboard
Key Performance
Information
1. Annualised
Income
2. Biogas Volume
3. Methane %
4. Methane Yield
5. Totalised
ODM/day
6. Calculated VSD
7. CHP Output
Electrical
8. FOS/TAC

14. 350kW Anaerobic Digester
ADvisorMVTM Sampled Data Entry
Sample ID
Sample
Entry
Acceptance
of Sample
Value
Automatic
Record of
Sample
Timestamp
Operator
comment for
each sample

15. 350kW Anaerobic Digester
ADvisorMVTM Fault Detection Log + Advisor
Process
Faults
Automatically
Detected
From Expert
System
Each fault
has a set of
recovery
Actions
Alarm
Manager
Automatically
records and
can send
emails to
Operators

16. Anaerobic Digester
ADvisorMVTM Statistical Monitoring Alerts
Process Faults
Automatically
Detected
using statistical
monitors
All important
Process
measurements
pre-configured
within the
ADvisorMV
software

17. Optimisation of Small Scale Anaerobic Digesters
Converting Data into meaningful information!
Outside Operational Constraints
Efficiency Reduction
Breaching Operational Guidelines
Unstable Operation
Through the removal of outliers, appropriate filtering and statistical classification it is possible
to present useful information to enable correct Operator Adjustments

18. Optimisation of Small Scale Anaerobic Digesters
Real Time Operational Supervisor
Performance Indicators, with Optimum Feed
rate suggestions
Sampled measurements and key process
measurements amalgamated to reveal
process character and health of the Digester
Provide remote connectivity to provide Essential Operational Information
Performance Indicators with Optimum
Feed Rate Guidance
Robust statistical monitor, providing
early warning of unusual behaviour

19. THE FUTURE OF SMALL
SCALE AD
#UKADBiogas @adbioresources
CHAIR:
SOPHIE GOODALL, HARPER ADAMS UNIVERSITY
PANEL:
DAVID LOVETT, PERCEPTIVE ENGINEERING
MICHAEL THOMPSON, RARE TECHNOLOGIES
DAVID KANER, ADVANCED ANAEROBICS
MARK CLAYTON, QUBE RENEWABLES