Day Two - UK AD & Biogas Tradeshow 2016 : R&I Hub

UK AD & BIOGAS TRADESHOW

6-7 JULY 2016NEC BIRMINGHAM

Can research and innovation rescue on-farm AD?

UK AD & BIOGAS TRADESHOW R&I HUB

ANGELA BYWATER & DR CLARE LUKEHURST OBE AD NET IEA TASK 37 UK

Potential viability of small scale AD

Clare T. Lukehurst OBEInternational Energy Agency

Bioenergy Task 37/Task 37 (UK)

Anaerobic Digestion & Biogas Association

July 7th 2016

Origin & purpose of the brochure

Request of the UK REA Biogas Group , farmers, landowners and RICS to establish:

• Types and designs of plant available• Establish factors affecting capital and

operating costs• Benefits of the plants

Role of the IEA Bioenergy Task 37

• Collate scientific and technical • experience worldwide

• Review of findings of both financial and environmental performance as reported in nearly 200 papers of which 120 key cited in the brochure

• Assess implications of the process at small scale for farmer AND policy maker

Small scale: Perceptions‘We know it cannot pay’ ‘Look at the costs’

£ 8,000 – £15,000 per kWeCommon knowledge- source of information?

Who says so?Consultants reports

Bank managers? Media accepts

End of discussion – small farm scale manure AD not an option

Too expensive: capital costs < £250kWe?(Source: IEA (2015) Small scale technical brochure))

SMALL SCALE?Digester (left) 20m3

33 family farms in Brazil?Supports 10 kWe CHP/ 5m3 /hrbiogas upgrading

Brazil Part of 33 - farm cooperative

22 km Gas Pipeline links farms

Norway 20 m3 slurry managementSystem 3,000 t/year Finland farmer built

with recycled partsSee case study

Switzerland co-digestion manure &crop CHP

1998 Finland 150 m3 digester CHPBuilt from recycled materials See Case study)

Switzerland manure +crop CHPGrid control to virtual power stationwww.iea-biogas.net

The Indian scaleManure ADmakes money-

Surplus gas goes to market- a cashcommodity

See Mutzner (2013) Workshop

http://www.iea-biogas.net/

Farmers thinking-structure for analysis

• Costs per kWel ??? No? Is AD for slurry a new money maker - GBP in

the bank? • Money wise I am no worse off -easier budget

forecasts & non monetary benefits

• AD a loss maker – no financial benefit

• Policy makers - no takers - no GHG reduction

The KEY IssuesCapital cost of the whole plantSource and cost of purchase moneyOperating costQuality of feedstock –amount of dirty water ThenSources of income- energy sales. incentives BUT Cash flow – avoided costs as important but but ? taken into account by bank

After 2 yrs operation 7 years laterAvoided expense 29-39k 35-38kNew income 130k-141k

Digester converted from former Heavy duty oil tanker

A key factor

Cash flow – avoided costs as important but ? taken into account by

the bank , finance company, policy advisers

Need to maximise non fiscal benefits

bank

The Way Ahead

Dual Policy approach Government GHG reduction policy

Energy industry for reinforcement of heat, gas and power distribution REWARD TOTAL GHG reduction

Markets - produce what the farmer wants and can afford to buy

SponsorsThe following sponsors through generous donations pay for UK to attend meeting and now bear the full cost of the IEA Bioenergy Task 37 (Energy from Biogas) UK membership subscription

An En, AFBI, AnDigestion, ADBA, Biogas Nord, Bioplex Technologies, Chesterfield Biogas, CNG Services, CLA,Clarke Energy, Edina Group, Envitech, EVH Engineering, Farm Energy, FM Bioenergy, Future Biogas, GOALS, GWE Biogas, J.H.Walter Sustainable Resource Management, Rural Planning Services, Malaby Biogas, Marches Biogas, Methanogen, Lutra, NETZSCH Pumps, Omex Environmental, Red Kite, Rob Heap Consultants, RH & RW Clutton, RICS, Sustraco, University of Southampton, UTS Biogas, Xergi

Avoided costs and self sufficiency

A key for the farmer? Thank you!

Can research and innovation rescue on-farm AD?


PAUL ADAMSDIRECTOR, SYNERTREE

Dr Hafez Abdo and Professor Robert Ackrill

Nottingham Business School – Nottingham Trent University

[email protected]

[email protected] funded by the British Academy/Leverhulme small

research funds

Green energy, fiscal incentive and conflicting signals:

analysing the challenges faced in promoting on-farm waste-

to-energy projects

mailto:[email protected]




• Research Aims and Objectives.

• Research Questions.• Methodological Approach.• Previous Similar Studies.• Analysis• Concluding Remarks

Outlines

UK Renewable Energy policy is nested within EU policy in a multilevel governance (MLG) setting. To gain analytical traction on suchcomplexity, this study analyzes policies promoting the on-farm generation of energy for heat and power, from farm and food waste, via Anaerobic Digestion.

• To illustrate the impact of UK policies on waste-to-energy AD on-farm projects in the East Midlands;

• To investigate the effects of UK energy policy and its instruments on promoting on-farm generation of energy for heat and power; and

• To explore and explain the impact of AD on energy, environmental and social elements in the East Midlands region of England.

Research Aims and Objectives

The first phase of our study will try to answer the following questions:

1. What challenges faces the on-farm waste to energy AD uptake in the East Midlands?

2. Which policy instruments influence the establishment of on-farm waste to energy AD projects on farms in the East Midlands, and how?

3. What incentives and support mechanisms are required to enhance the on-farm waste to energy AD projects on farms in the East Midlands?

Research Questions – Phase One

The next phase of this study will try to answer the following questions:

1. How does the MLG setting of UK RE policy affect policy delivery?

2. What theoretical insights does MLG offer when seeking to reform UK RE policy in order to promote more effective take-up of waste to energy technologies?

3. How does our case study inform the theoretical formulation of coherent multilevel governance in areas characterised by considerable policy complexity?

4. How does our case study, in a policy area that is relatively new, inform the longstanding literature on path dependency and the challenges of switching to new technologies?

Research Questions – Phase Two

• Our research is of an exploratory explanatory nature and our researchquestions have both qualitative and quantitative aspects; therefore answering these questions requires collecting and analysing qualitative and quantitative data.

• Our data will be collected via three main instruments:• Phase one: document analysis and questionnaire survey• Phase Two: document analysis and interviews.• Whilst document analysis and questionnaire methods will aid the

exploratory side of the project, interviews would aid the explanatory aspect.• Government, energy-related, documents will be searched and analysed• Questionnaires were sent to 1,589 farmers in the East Midlands region

of England (Nottinghamshire and Derbyshire). 158 questionnaires were received back.

• 25 interviews are planned with different personals connected to the AD business: Farmers, Policy Makers, AD Consultants and Academics.

Methodological Approach

Results of Questionnaire Survey - Phase One Descriptive Statistics # %

Farm Location Nottinghamshire 78 51

Derbyshire 75 49

Farmer Gender Male 141 92

Female 12 8

Type of FarmArable 56 37

Livestock 51 33

Mixed 46 30

Farm Ownership

Owned by you 88 57

Shared ownership 29 19

Rented 16 10

Other 20 13

Annual Farm Income

Less than £10,000 8 5

£10,000 - £19,999 6 4

£20,000 - £29,999 4 3

£30,000 - 49,999 8 5

£50,000 - £74,999 9 6

£75,000 - 99,999 10 7

£100,000 - £149,999 14 9

£150,000 - £199,999 11 7

£200,000 and over 61 40

Prefer not to answer 22 14

AD Plant Yes 1 1%

No 152 99%

Production of Renewable EnergyTotal*

# %

85 55.5

Biomass 15 14

Wind 16 15

Solar PV 60 57

Other RE 15 14

Our respondents purchase different sources of non-renewable energy.Electricity and diesel are the most popular forms of energy being used in farms.Other forms of energy sources being purchased by farmers in our sample include logs and wood, however this is the least non-renewable sources of energy purchased.

Purchase of off-farm sources of non-renewable energy

0 20

40

60

80

100

120

140

Coal

Gas

Electricity

Diesel

Petrol

Other

In terms of renewable energy, our respondents purchase energy generated by solar PV the most, followed by energy generated by biomass.Biomass sources include wood and logs

Purchase of off-farm sources of renewable energy

0

2

4

6

8

10

12

14

16

PV Solar

Wind

Biomass

Other

Apart from using AD, the majority of our respondent farmers generate energy using PV solar.They generate renewable energy using other means such as wind and biomass.Feedstock used for biomass includes oil seed, slurry, wood, maize and woodchip.Other forms of on-farm generation of renewable energy includes ground heat source pumps, air source heat pump and timber.

On-Farm generation of Renewable Energy

0

10

20

30

40

50

60

70

Biomass PV Solar Wind Other

Of our sample respondents, 100 farmers produce renewable energy. Of those, 34 make off-farm sale of part ofthe renewable energy they produce on-farm

Off-Farm Sale of Energy Generated

35%

11%

54% Regularly

Occasionally

No

Awareness of UK Renewable Energy Policy

• The majority of our respondents (127) believe that renewable energy promotion is the most important rational.

• Respondents suggested that some of the other underpinning reasons of the government policy to promote AD are: complying with EU Directives, controlling emissions, diversifying energy sources and to show that the UK government is ‘doing something’, to please their EU cronies, lack of investment by government in power generation for over a decade, to tick the ‘we are doing something about global warming’ box, and to meet UK renewable energy targets.

Rationales underpin governmental policy to promote AD

127

53

20

19

0 20 40 60 80 100 120140

Renewable energy promotion

Waste-disposal

Income-generation

Other

0 10 20 30 40 50 60 70 80 90

Not suitable for farming activities

Lack of information about AD technologies

Inadequate financial incentives

Overly-burdensome regulations

Unstable policy or uncertain future policy

Problem with connectivity to the National Grid

Taxation Policy

Access to Finance

Controls over the use of waste products

The off-farm movement of food waste and digestate

Other

Reasons for not adopting on-farm AD Technology

• concerns over increasing labour force in the farm and possible need for dependence on contractors to run the AD business.

• lack of trust in the stability of FiT.

• lack of governmental involvement in connecting AD energy products to the grid.

• planning complication.

• smell of the process in a residential area. • AD is too expensive to be invested in by farmers.

• location of farm near built area. • availability of finance to start-up AD projects.

• local objection to planning permission. • unclear and insecure income from AD.

• lack of sufficient feedstock.• age of farmers that do not allow the

adoption of AD.

• size of farm does not justify the significant investment in AD.

• type of ownership of farm as being rented does not justify investing in AD.

• focusing on building and enhancing farming business rather than shifting focus to a new investment in AD.

• AD power and heat products are not of usefulness to farm.

Other Reasons for non-adoption of AD

• Government policy is fragmented on energy/ transport/food

• I would say grant aid to help smaller farmers work together

• We need cooperation between farmers and bigger incentives, as in Germany

• smaller models of AD units to suit smaller farms

• Grants, interest-free loans• More security of support to

allow banks to fund AD• tax advantages• Perhaps if somehow the

feedstock production could be subsidised this would take some risk out

• Higher and more long term stable FITs

• kick-starting is good but must not be subsidy dependant

Required Incentives for AD Uptake

Awareness

• “does anyone know the cost effectiveness of maize fed AD without subsidy. The amount ofdiesel burnt/energy spent on maize growing and supply surely cannot equate to the small amount of gas produced?”

• “Costs for start-up seem too high. Is this because of new technology?”

• “If we had a unit it would have to be very small scale. There is very little information about this”

• “The public have no idea about AD. When they learn anything they are invariably suspicious”

• Information about the cost of having an AD unit installed, payback period, cost of feedstock, taxes and subsidies and the required fuel to run the AD unit are some of the information required by farmers to make decisions on AD uptake

Awareness of AD

Awareness of UK Governmental RE Incentives and Measures

0

20

40

60

80

100

120

140

UK Renewable Energy Roadmap

Renewable Obligation (RO)

Feed-in Tariffs (FiTs) Renewable Heat Incentive (RHI)

Renewable Transport Fuel Obligation

(RTFO)

Electricity Market Reform (EMR)

'Connect and Manage'

Transmission Access Regime

Very Aware Somewhat Aware Know the name only Not at all aware

• FiTs is a key incentive measure for AD uptake in the UK.

• Stability of FiTs rates is a key for easing investment uncertainty in AD technologies.

• Financial support and access to finance is essential to promote AD uptake and hence renewable energy generation.

• Planning permission and complexity of regulations are still main barriers for AD uptake and the government is required to review these in order to boost generation of renewable energy from AD technologies.

• Spreading awareness of AD technology and governmental renewable energy policy’s objectives and tools is key for on-farm AD uptake.

Concluding Remarks

QUESTIONS?

THANKYOU

The next phase of our research is focused on in-depth analysing incentives and disincentives of AD uptake, and on the impact government renewable policy and taxation measures on the uptake of on-farm AD.

We would like invite you to take part in this phase of the research by means of an interview. If you would like to participate in this study please contact us.

Professor Rob AckrillEmail: [email protected]

Dr Hafez Abdo618, Newton Building Nottingham Business School Burton StreetNottingham, NG1 4BU Email: [email protected] Tel: 0115 848 6098Mobile: 07872113763

A Call for Participation



Towards digestible plastics: The impact of plastic bin liners on Anaerobic Digestion

Dr Tanja Radu, Dr Richard Blanchard, Prof Andrew Wheatley

Introduction

Plastics Food waste Plastic separation Biodegradable plastics experiments Conclusions

Plastics

Plastics Europe

Plastic Markets

Post Consumer Waste

Plastic Problems

www.plasticpollutioncoalition.org

awesomeoceans.com

Food Waste

Losses in supply chain fields, processing, transport, shops, catering, home.

Food waste

UK around 14M tonnes per year Lovefoodhatewaste.com

How to deal with food waste and plastic packaging?

Plastic waste/food waste collection

Monday 1 May 2023

• Every year, over 10 Mt of packaging is placed on the UK market. About half that amount (5 Mt) goes to households, where it accounts for about 20% of the waste stream. The other half is used in the Commercial and Industrial sectors, where it accounts for about 10% of the waste stream.

(Source: Defra http://www.defra.gov.uk/news/2010/10/26/uk-packaging-recycling-targets/)

• Plastic waste (packaging, containers, bags, lids, cups) accounts for 10-15% of total waste

• Food waste collection using plastic bin liners is becoming increasingly popular

Plastic bags in AD industry

Monday 1 May 2023

The bags or fragments of them can entirely or partially follow three different paths in an AD plant:

Route 1: Bioplastic fragments fed into the digester along with the food waste. After digestion, the digestate with possible remains of the plastics are composted for aerobic stabilization and mature compost production.

Route 2: Bioplastic fragments sorted out during the pretreatment stage, skipping the digestion stage and re-joining the aerobic composting stage of the digestate.

Route 3: Bioplastic fragments sorted out during the pretreatment stage and sent to disposal because of high contamination of the pretreatment residues by non-compostable materials (e.g. conventional plastics) or because of the lack of a final aerobic stage for compost production.

Source: Christian Garaffa and Rhodes Yepsen, BioCycle September 2012, Vol. 53, No. 9, p. 37

Regardless of separation method, some of the plastic will inevitably end up in AD digester

Plastic Separation

Stage 1 hammer mill Stage 2 hammer mill

Food slurry

To AD

Biodegradable plastics

Alternative, based on biological materials such as corn or potato starch and polymer-alcohols

But do they biodegrade? Plastics, in general, often degrade and weather when

exposed to UV light. Some biodegradable plastics need prolonged exposure of temperatures above 50oC to fully break down.

Complete biodegradation of plastic occurs when none of the original polymer remains, a process involving microbial action; i.e. it has been broken down to carbon dioxide, methane and water.

http://www.unep.org/gpa/documents/publications/BiodegradablePlastics.pdf

PLA





Motivations

Plastic bags are an ideal material for the collection of wet wastes, but poor biodegradability.

Accumulations of plastic residues in the environment are an urgent and serious concern.

AD is the most common process for the treatment and conversion of wet organic waste to energy.

Biodegradable plastic would encourage the hygienic collection of household food waste for AD.

Current practice: separation of bags from the food waste prior to digestion, a difficult operation causing loss of organic material and increased costs.

Some of the plastic material inevitably ends up in the digesters and potentially on land.

Experimental Set-up

Standard 10 litre vertically stirred bioreactors at 37oC. Plastic bags were used as a sole substrate and digesters

performance was compared with the control digester fed by sewage sludge only.

pre-treated at 70oC for 1hr, according to the Animal By-product Regulations.

feeding 5 days per week, no feeding at weekends. The organic loading rate was 2.65 g VS/l/day. Monitoring: Cumulative gas production (on line), gas quality

(manually by infra-red). Stability indicators (Ripley’s Ratio, volatile fatty acids, pH and ammonia).

Materials: Alcohol and starch-based bag samples used for the production of biodegradable bags.

Cumulative Biogas Production

Capillary Suction Time

Methane Yield

Conclusions

CONCLUSIONS:

• Poor biodegradability for both types of bags at both temperatures of pre-treatment

• Using bags as sole substrate, biogas production stalls and methane percentage in biogas decreases

• Stability indicators remain stable, indicating that material is inert rather than toxic to digestion.

• Alcohol polymer-based bags completely dissolved when treated at 70oC whereas the starch ones did not, and in this case only digester viscosity rapidly increased (CST)

• An increase in total solids in all test reactors was observed as the plastic accumulated. This may have implications for the mixing of the digesters, with an increase in torque on the stirrer blades, resulting in greater energy consumption.

Thank you

ACKNOWLEDGEMENT: This research is funded by Engineering and Physical Sciences Research Council (EPSRC) grant EP/J000361

For further details please contact Tanja Radu at [email protected] or +44 (0)1509 223808

Digesting the indigestible: plastic and indigestible bags in food waste and how to manage them


TONY CLUTTENPROCESS SALES MANAGER, HUBER TECHNOLOGY

DIGESTING THE INDIGESTIBLEORGANIC RECOVERY AND LANDFILL REDUCTION

Grit ,glass. Bone, eggshell heavy and light plastics are not Digestible. But why throw the baby out with the bath water.

Digesting the indigestible-organic recovery and landfill

reduction July 2016 www.huber.uk

Household and supermarket waste Ball Milled MSW

HUBER’S EXPERTISE

• Huber are Liquid / Solid Separation Engineers and have a wealth of experience gained in Municipal and Industrial applications throughout the world.

• However many of the problems created in Anaerobic Digestion have required different solutions based on Huber’s expertise but adapted to suit.

In this paper we look at:- Removal of oversize Washing oversize to reduce volume and recover organics Removal of Grit and glass Washing Grit and Glass to recover organics Starch Bags Removal of floating debris Removal of Plastics both Pre and Post Digestion



HUBER TECHNOLOGY . www.huber.UK

Digesting the indigestible-organic recovery and landfill reduction July 2016

SIMPLIFIED FLOW DIAGRAM

Screen Grit Removal

Sludge Handling

Digestate Cleaning

Fibre and plastics removal

Grit washing

Screenings washing

INDIGESTIBLE DRIVERS• Waste operators wishing to dispose of waste at landfill sites in England,

Wales and Northern Ireland will need to pay £84.40 per tonne from 1 April 2016

• With gate fees dropping and disposal costs rising the rejects need to be reduced.

• Wear is high due to grit and glass• The bugs can’t digest inorganics.• Downtime is high due to inorganics settling in the system• Gas yield is down if the digester is partly full of inorganics• Greenhouse gas reduction• Vermin control• Legislation• Landfill shortage• NPK recovery• Plastics recovery (tomorrow)



https://www.bing.com/images/search?q=Picture+refuse+site&id=806C2C7D075E4858EE106B40C4767B439E8E141D&FORM=IQFRBA

DE-PACKAGING

De-Packaging can be done in numerous ways and each handles the plastic , grit and oversize content differently:-• Hammer mills- reject oversize. Rejects often containing organic biosolids.• Pulverisers- May just send all parts forward in the soup cut up or

segregate light and heavy Fraction from soup• Turbo Separators such as Tiger and Attritor spin out oversize.• Slitters –slit all contents and wind sift off plastics.• Squeezers- Squeeze the food from the packaging• Autoclaves- pressure cook total feed. • High pressure water to wash out organics

Every type provides a different soup including different contaminants





THE QUALITY AND QUANTITY OF PLASTICS REJECTS DEPENDS ON THE DE-PACKAGING PROCESS AND

FEEDSTOCK. WE HAVE FIGURES VARYING FROM 7 TO 22% FROM SOURCE SEGREGATED AND SUPERMARKET WASTE.

LETS GET THE ORGANICS BACK IN THE SOUP

RECOVER ORGANICS FROM REJECTS

TIGER DEPACKAGING-TRIAL WASHPRESS UNDER DISCHARGE

TIGER REJECT 7.5% WASHED AND DEWATERED ORGANICS RETURNED OF FEED SCREENINGS TO SOUP 40-60% REDUCTION



GERMAN TRIALS –Behind a MEWA Depackaging unit

Pulped food waste feed

Washpress size 6 under MEWA rake discharge

Washed screenings



Having undertaken several Lab and full scale trials we have concluded that each de-packaging machine type and feedstock gives us varying results so more trials are necessary. However simple wash trials indicate potential to:-

1. Reduce tonnage to landfill and costs.2. Give cleaner solids3. Recover volatile solids and COD

Screenings Wash trials

Unwashed screenings from Press

Hand Washed screenings No Pressing.

Settled washwater. Left 30minutes settling right 2 minutes



Combination unit of screen and Longitudinal Grit Trap

Huber have a range of combination units handling 6 to 120TPH of Digester feed at 6 to 14% Dry solids.

SCREEN AND GRIT TRAP

Screen

Dewatering unit

Longtitudinal Grit Trap



An Inlet Screen (Ro 1 BIO) is included in the design incorporating extra rakes, reinforced 10 or 15mm screensLarger drives and higher solids removal rates to cater for the higher solids loading

This screen incorporates screening washing, dewatering, and elevating oversize utilising 1 drive.

Oversize screen

If the de-Packaging unit incorporates its own screen this is not required. However oversize is often contaminated.

SCREENINGS WASHING-Swedish Plant

• Loss of digestible material (Biomass) is to be avoided and Huber have incorporated screenings washing within the auger of the Ro1 Bio with some success, however the plastic content and the size of the pulped solids make washing in the auger more difficult so we would advocate using a wash press. Retrofitting is possible.

Wash Press in Sweden working on screenings from screen

Screenings before washing

Screenings after washing

The weight deduction to Landfill is 10-14% but this depends on the upstream process. Digesting the indigestible-

organic recovery and landfill reduction July 2016

www.huber.uk



German sewage trials

Trials in Germany on sewage screenings gave up to 20% increase in gas yield by washing the screenings of Faeces and returning the organic carbon to the Anaerobic digester

The photo shows a UK site where 2 washpresses are installed to give clean screenings but return the organics back to feed the bugs downstream

Powerful agitation drive

Clean Dry screenings

PLC controlled valve



GRIT AND GLASS

Grit and Glass are a major problem to the Operations and Maintenance department causing wear, blockages and mixing power increases. But the other hidden enemy is sedimentation in the digester. If your Digester is say 30% full of grit then that’s 30% less retention time with subsequent gas losses, heating costs etc.

Grit and glass and heavy plastic can be settled out on a Huber longitudinal grit trap

GritGlass



LONGTITUDINAL GRIT TRAP TO REMOVE HEAVY FRACTION

12.5% DS Food Waste Soup Ro5 Bio 50 in UK

Trapezoidal channel Grit and glass removed

GRIT WASHING• Simarly biodegradeable material around the grit can be

washed out using a grit washer to increase gas yield

Digesting the indigestible-organic recoveryand landfill


RETROFITTING A GRIT TRAP AND WASHER



An existing Anaerobic Digestion plant in Northern Ireland takes in a mixture of Food waste and green waste. In order to reduce the volume of grit in the system which causes a lot of blockages, sedimentation and wear issues, Huber were asked to look at the installing a Grit removal plant between the Hammer mill’s and the soup stock tank.

No pumps between grit trap and washer



RESULTS

Clean grit, glass eggshell bone and sea shells Removed from soup(Indigestables)

Organics back in the soup

1. Reduced Landfill2. Recovered organics



Strainpress Plastics removal

For plastics and packaging removalwe have fitted a Strainpress prior to digestion to remove as much fibre and plastics as

possible or after digestion to separate liquid and solids and protect down stream product.

Strain press opened for inspection

STAND J502



PLASTICS REMOVALStrainpress – where is it applied

Delivery by TruckSludge / Scum

Sand trap

Primary tank

Secondary tank

Secondary sludge

Primary sludge

Scum / Grease

CourseStrainpress ®

DewateredScreenings

Drying

Dewatering

Alternative applicationStrainpress ®

Heat exchanger

Disposal

Digester

DewateredScreenings



The Press works under 1 bar pressure and the slurry is pumped or gravity fed into the inlet drum. The free liquor drains through the mesh and the solids are squeezed and turned by the auger towards the discharge cone.

The discharge cone and auger is tapered to compact the screenings against a pneumatically controlled plug which releases the screenings when the pressure is reached

CakeSlurry Inlet Filtrate out

Compaction zoneDewatering Pneumatic cone

Strainpress



PRE-DIGESTION

Removal of plastics pre-digestion needs careful thought to avoid heavy disposal charges of oversize and loss of gas production.Throughput can be low due to rheology.Gas yield can be reduced. We can remove all + say 10mm wash and return Organics



6 off Strainpresses fitted with 5 and 6mm baskets handling 20M3/h at 8-10%DS producing 50% DS cake.

Fibres glass and plastics are removed from MSW before Digestion

BIFFA WANLIP RDF REMOVAL



POST DIGESTION SHANKS-WESTCOTT PARK STRAINPRESS

At Westcott Park we have a Strainpress fitted with a 3mm mesh screening digestate between the digester and the 3 Pastuerisers

Screenings removed which otherwise would be on the fields



Thermally treated food waste trials

BEFORE AND AFTER



Without Strainpress With Strainpress

Results of trials in Italy

Tel.: 01249 765050eMail: [email protected]

Thank you very much for

your attention



Networking Lunch


12:30 – 13:30

The digestate challenge: research to maximise nutrient use efficiency


ANDREW MCLEODCRANFIELD UNIVERSITY

Digestate processing Using membranes: breaking the barriers to valorisation

Dr Robert W LovittMembranology Ltd / Swansea University

The challenges The problems of digestate:

– Environmental Hazardous– Difficult to handle– Dilute

• Storage• Transport

– Variable composition– Seasonal use

Slurry

Energy crops

Food waste

Anearobic Digester

Digestate storage

Biogas CHP Unit

Electricity

Heat

Digestate to land

Slurry

Energy crops

Food waste

Anearobic Digester

Digestate storage

Biogas CHP Unit

Electricity

Heat

Digestate to land

Concentration

Water

Nutrient Formulation

FertiliserGrowth media

PHBProteinFats/oilChemicals

Current situation

Added value possibilities

Reduced storage

Reduced transport and distribution costs

Membrane technology• Membrane technology now a mature process with many large

scale applications– Low cost simple processes easily intgerated with digestate processing

• We have applied this to digestate sludge processing– Solid liquid separations– MF/UF/NF/RO

Hollow fibre filters

Spiral wound membrane

Concentrating Nutrient

• Reverse Osmosis

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwium5fxu9LNAhWLD8AKHeZiBB0QjRwIBw&url=http://reverseosmosissystemsreview.com/how-does-reverse-osmosis-work&psig=AFQjCNF2vab2IKaiXansR8dGghpOBoWFiA&ust=1467469445734028

Recovery of nutreints

• Phosphate– Critical resource

• Ammonia– Large carbon footprint

• Metals– Essential and important

micronutrients

• Water– Clean decontaminated

water

Reformulation of nutrients

• Fertilizers – Precise formulation, solid or concentrated form

• Algae growth media– Protein, Oils

• Microbial growth media– PHB, Oils, Protein, Platform chemicals

• Plant growth media– Hydroponics

The digestate challenge: research to maximise nutrient use efficiency


DAVID STYLESLECTURER, UNIVERSITY OF BANGOR

98

Dr David Styles (Bangor University)

Dr Paul Adams (Bath University)

Environmental balance of digestate upgrade

© Tim Scrivener

METHOD

RESULTS (GWP)

RESULTS (AP)

RESULTS (FRDP)

CONCLUSIONS

Climate change

Water qualityAir quality

Nutrient cyclingEnergy balance

Economics…

Thanks for your attention!

Email: [email protected]

01/05/2023 104LCAD EcoBalance: ADBA Forum 2015


Dr Richard Wadsworth; Dr Ruben Sakrabani; Dr Stephen Hallett

Phosphate acceptance map: A tool to determine suitable land for the application of biosolids – potential for AD

Many modern agricultural soils are significantly degraded

Increase in Inorganic Fertilisers

Higher CropProductivityPopulation2

Increases

Increased requirements for

food

Reduction in SOM

Reduction in Nutrient

Retention

Introduction

Rickson RJ, Deeks LK, Graves A, Harris JA, Kibblewhite MG, Sakrabani R (2015). Input constraints to food production: the impact of soil degradation. Food Security (accepted). DOI 10.1007/s12571-015-0437-x

Biosolids/Anaerobic digestates

Research Question ?

• Where can we target application of biosolids to meet crop nutrient demand using national geo-temporal environmental ‘Big Data’ ?

Project Overview

Three test locations : Silsoe, Shropshire and North Wales

NUE

CU : LandIS – Data on soil and crop

Water Utilities : Data on biosolids

UKCP09 : Data on climate – past and future projections

Digital Map + protocol and user guide

Crop uptake for at least 3 years after application of biosolids

Data Flow

Stakeholder groups and physical constraints

Constraint Group 1 Group 2 Group 3 Group 4 Group 5

Protected Area - pollution * *Protected Area - biodiversity * *Protected Area - landscape * *Heavy metal accumulation * *Erosion > soil formation * *Distance transported * *

PAM data and maps organised in ESRI ArcGIS Online

Lessons from biosolids to AD

• Data availability is challenging – sensitive matter• Validation to other locations• Industry engagement

• Locations of AD plants • Volume of AD generated • Nutrient (P) content of AD and its variation depending on feedstock

used• Land bank applied with AD currently and future projections • Yield response of crops applied with AD – Nutrient Use Efficiency• Data is required for the above • PAM for biosolids can be adapted for AD

Summary

• PAM offers new tool to manage biosolids use in sustainable agriculture

• A water treatment works is a P ‘mine’ – can utilise PAM to target suitable crop / landbank

• PAM utilises stakeholders interests and constraints

• PAM – needs to be further exploited with additional dataset and other application such as AD sector

Thank you, any questions?
