Treatment and Use of Treatment and Use of Sewage Sludge Sewage - - PowerPoint PPT Presentation

Workshop on Knowledge and Practices of Using Treated Sewage Sludge on Land

Treatment and Use of Treatment and Use of Sewage Sludge Sewage Sludge Review of COST 68/681 Review of COST 68/681

Developments around the Developments around the Sludge to Land Directive Sludge to Land Directive Jeremy Hall Jeremy Hall

Development of Sludge Use Development of Sludge Use

1859 1859 John Mechi John Mechi ‘ ‘sewage is the life sewage is the life-

• blood of the nation

blood of the nation’ ’ 200 t London sewage = 3 200 t London sewage = 3½ ½ cwt (178 kg) of guano cwt (178 kg) of guano 1908 1908 Royal Commission on Sewage Disposal Royal Commission on Sewage Disposal – – sludge sludge considered as relatively poor source of plant nutrients considered as relatively poor source of plant nutrients 1909 1909 Board of Agriculture and Fisheries recommends sludge Board of Agriculture and Fisheries recommends sludge as a very slow acting manure as a very slow acting manure 1937 1937 MAFF advises sewage sludges are not very promising MAFF advises sewage sludges are not very promising as a source of plant food as a source of plant food 1940s 1940s Rothamsted pessimistic about agronomic value Rothamsted pessimistic about agronomic value 1946 1946 USA Federation of Sewage Works Authorities USA Federation of Sewage Works Authorities Manual of Practice No. 2 on Manual of Practice No. 2 on ‘ ‘Utilization of Sewage Utilization of Sewage Sludge as Fertilizer Sludge as Fertilizer’ ’ 1954 1954 Ministry of Housing and Local Government recommends Ministry of Housing and Local Government recommends liquid sludge application to land liquid sludge application to land 1950/60s 1950/60s Marked increase in mineral N use and rapid Marked increase in mineral N use and rapid expansion of sludge use on farmland expansion of sludge use on farmland

1960 1960 Fertiliser replacement advice Fertiliser replacement advice -

• 250 kg N/ha in 25 t/ha raw

250 kg N/ha in 25 t/ha raw sludge, N fertiliser adjusted assuming 50 sludge, N fertiliser adjusted assuming 50-

• 60% availability

60% availability 1966 1966 Coker demonstrated N value of liquid sludge Coker demonstrated N value of liquid sludge 1970 1970 ‘ ‘Taken for Granted Taken for Granted’ ’ report report Working Party on Sewage Disposal Working Party on Sewage Disposal 1971 1971 ADAS 10 Guidelines ADAS 10 Guidelines 1972 1972 EC DGXII initiates COST 68 EC DGXII initiates COST 68 1977 1977 Working Party on Disposal of Sewage Sludge to Land Working Party on Disposal of Sewage Sludge to Land 1979 1979 Royal Commission on Environmental Pollution, Royal Commission on Environmental Pollution, Seventh Report Seventh Report ‘ ‘Agriculture and Pollution Agriculture and Pollution’ ’ 1981 1981 Report of Committee on the Disposal of Sewage Sludge Report of Committee on the Disposal of Sewage Sludge 1982 1982 EC Directive proposal EC Directive proposal 1986 1986 Publication of EC Directive Publication of EC Directive 1989 1989 Implementation of EC Directive Implementation of EC Directive 1990 1990 COST 681 ends COST 681 ends

Development of Sludge Use Development of Sludge Use

What is COST What is COST

• European Cooperation in the Field of Scientific and

European Cooperation in the Field of Scientific and Technical Research Technical Research

• An intergovernmental European framework for international

An intergovernmental European framework for international co co-

• operation between nationally funded research activities
• peration between nationally funded research activities
• Add value to non

Add value to non-

• competitive and pre

competitive and pre-

• normative research

normative research

• Secretariat provided by EC (originally DGXII)

Secretariat provided by EC (originally DGXII)

• The oldest European networking system in research,

The oldest European networking system in research, established in 1971 established in 1971

• Still going, currently consists of 34

Still going, currently consists of 34 Member Countries and Member Countries and

• ne cooperating state
• ne cooperating state

COST 68 COST 68

• Origin in 1967

Origin in 1967 (PRESETT Group)

(PRESETT Group)

• COST 68 from 1972

COST 68 from 1972

(33 labs, 13 countries, 3 study groups) (33 labs, 13 countries, 3 study groups)

• COST 68 bis from 1977

COST 68 bis from 1977 (14 countries)

(14 countries)

• COST 68 ter from 1981

COST 68 ter from 1981 (15 countries)

(15 countries)

Five working parties: Five working parties:

1.

• 1. Sludge Processing

Sludge Processing 2.

• 2. Chemical Pollution of Sludge

Chemical Pollution of Sludge 3.

• 3. Biological Pollution of Sludge

Biological Pollution of Sludge 4.

• 4. Valorisation of Sludge

Valorisation of Sludge 5.

• 5. Environmental Effects of Sludge

Environmental Effects of Sludge

COST 681 COST 681

• COST 681 from 1983 ending in 1990

COST 681 from 1983 ending in 1990

• Incorporated liquid agricultural wastes

Incorporated liquid agricultural wastes

• Five working parties:

Five working parties:

1.

• 1. Processing of Organic Sludge and Liquid Agricultural Wastes

Processing of Organic Sludge and Liquid Agricultural Wastes 2.

• 2. Chemical Contamination of Organic Sludge and Soil

Chemical Contamination of Organic Sludge and Soil 3.

• 3. Hygienic Aspects of Treatment and Use of Organic Sludge

Hygienic Aspects of Treatment and Use of Organic Sludge 4.

• 4. Agricultural Value of Organic Sludge and Liquid Agricultural

Agricultural Value of Organic Sludge and Liquid Agricultural Wastes Wastes 5.

• 5. Environmental Effects of Organic Sludge and Liquid

Environmental Effects of Organic Sludge and Liquid Agricultural Wastes Agricultural Wastes

Host Countries of Working Party Host Countries of Working Party Workshops & Conferences Workshops & Conferences

D D UK UK CH CH E E CH CH D D S S UK UK I I D/NL/F D/NL/F D/B D/B CH/B CH/B WP5 WP5 GR GR NL NL I I UK UK A A F F Int.Conf. Int.Conf. D D UK/SF UK/SF 1990 1990 UK UK S S 1989 1989 CH CH NL NL B B I I 1988 1988 E E IR IR IR IR D/S/F D/S/F 1987 1987 1986 1986 DK DK F F D/F D/F UK/NL UK/NL 1985 1985 I I D D D D GR GR 1984 1984 S S SF SF NL NL IR IR 1983 1983 N N CH/I CH/I CH CH CH/B CH/B 1982 1982 D D UK UK B B D D 1981 1981 NL NL UK UK I I I/S I/S 1980 1980 F F I/NL I/NL UK UK F F 1979 1979 F F DK DK D D UK/CH UK/CH 1978 1978 WP4 WP4 WP3 WP3 WP2 WP2 WP1 WP1

Coordination with Other Networks Coordination with Other Networks

• DGVI Effluents from Intensive Livestock

DGVI Effluents from Intensive Livestock – – 1973 1973-

• 82

82

• FAO European Network on Animal Waste Utilisation

FAO European Network on Animal Waste Utilisation (now RAMIRAN) (now RAMIRAN) – – since 1974 since 1974

• FAO Odour Group

FAO Odour Group

• EC Composting Group

EC Composting Group

• IWA Specialist Group on Sludge Management

IWA Specialist Group on Sludge Management

• IWA Sludge Network

IWA Sludge Network – – since 1975 since 1975

• EWA Working Group on Sludge

EWA Working Group on Sludge

• CEN/TC 308 Characterisation of Water Cycle Sludge

CEN/TC 308 Characterisation of Water Cycle Sludge

Working Group 1 Working Group 1 -

• Analytical methods (CEN standards)

Analytical methods (CEN standards) Working Group 2 Working Group 2 -

• Codes of good practice

Codes of good practice Working Group 3 Working Group 3 -

• To preserve and extend sludge outlets

To preserve and extend sludge outlets

Papers published by EC Papers published by EC in Proceedings and Reports in Proceedings and Reports

• WP1

WP1 257 in 16 publications 257 in 16 publications

• WP2

WP2 63 in 9 publications 63 in 9 publications

• WP3

WP3 237 in 23 publications 237 in 23 publications

• WP4

WP4 245 in 20 publications 245 in 20 publications

• WP5

WP5 173 in 17 publications 173 in 17 publications Total Total 975 papers 975 papers

Drivers for Change Drivers for Change

• Poorly controlled and widespread use of

Poorly controlled and widespread use of untreated sludge untreated sludge

• Growing awareness of environmental and

Growing awareness of environmental and health risks health risks

Sewage sludge Sewage treatment Landfill Agriculture

Urban Waste Water Directive

Incineration

Landfill Directive Sludge in Agriculture Directive

Water treatment

Shellfish Directive Fisheries Directive Bathing Directive Ecological Directive Surface Abstraction Dir. Nitrate Directive Pesticides Directive

Aquifers

Groundwater Directive

Customer

Detergent Directives Drinking Water Directive Dialysis Directive Hazardous Waste Incineration Directive Waste Framework Directive Hazardous Waste Directive

Industrial effluent

Dangerous Substances Directive

River catchments Sewage sludge Sewage treatment Landfill Agriculture

Urban Waste Water Directive

Incineration

Landfill Directive Sludge in Agriculture Directive

Water treatment

Shellfish Directive Fisheries Directive Bathing Directive Ecological Directive Surface Abstraction Dir. Nitrate Directive Pesticides Directive

Aquifers

Groundwater Directive

Customer

Detergent Directives Drinking Water Directive Dialysis Directive Hazardous Waste Incineration Directive Waste Framework Directive Hazardous Waste Directive

Industrial effluent

Dangerous Substances Directive

River catchments

• Increasing

Increasing environmental environmental regulation regulation throughout throughout Europe Europe

• Sensational media raising

Sensational media raising public and retailer anxiety public and retailer anxiety

Press Headlines Press Headlines

‘ ‘Back to Nature Manure Causes Alarm Back to Nature Manure Causes Alarm’ ’ Sunday Times 1973 Sunday Times 1973 ‘ ‘Sewage Fertiliser 10 Times Too Dangerous Sewage Fertiliser 10 Times Too Dangerous’ ’ Guardian 1978 Guardian 1978 ‘ ‘Health Men Check Deadly Poison Health Men Check Deadly Poison’ ’ Oxford Times 1979 Oxford Times 1979 ‘ ‘Prison Threat Over Sludge Dumping Prison Threat Over Sludge Dumping’ ’ Guardian 1981 Guardian 1981 ‘ ‘Britain in a Stink Over Raw Sludge Britain in a Stink Over Raw Sludge’ ’ New Scientist 1982 New Scientist 1982 ‘ ‘Poison Warning Was Ignored Poison Warning Was Ignored’ ’ Daily Mirror 1982 Daily Mirror 1982 ‘ ‘Sewage Sludge Is It Safe? Sewage Sludge Is It Safe?’ ’ Big Farm Weekly 1984 Big Farm Weekly 1984 ‘ ‘The Sludge that Threatens the Foundations The Sludge that Threatens the Foundations

• f Britain's Farming Heritage
• f Britain's Farming Heritage’

’ Guardian 1984 Guardian 1984 ‘ ‘Metal Mayhem Metal Mayhem’ ’ Farmer Farmer’ ’s Weekly 1985 s Weekly 1985

‘Fields of Blood’ ‘Fields of Blood’

Approaches to Setting Approaches to Setting Limits for Contaminants Limits for Contaminants

Increase based on risk

assessment

Minimum practical increase

Minimise risk exposure

No accumulation

No hazard Increasing level of precaution (and cost)

Risk Assessment Risk Assessment

• US EPA Rule 503

US EPA Rule 503

– – Largest risk assessment in the field of Largest risk assessment in the field of environmental protection environmental protection – – 11 year program and cost US$15 million 11 year program and cost US$15 million

• In Europe, RA used by many sectors but

In Europe, RA used by many sectors but not for sludge not for sludge

• Recent initiative by ILSI

Recent initiative by ILSI – – RA methodology RA methodology for standards for organic contaminants in for standards for organic contaminants in sludge used in agriculture sludge used in agriculture

Heavy Metals: Concerns Heavy Metals: Concerns

• Control of concentrations in sludge

Control of concentrations in sludge

• Relative concentrations between sludge and soil

Relative concentrations between sludge and soil

• Accumulation / mobility in soil

Accumulation / mobility in soil

• Toxicity to crops (Zn, Cu and Ni)

Toxicity to crops (Zn, Cu and Ni)

• Toxicity to animals (Cd, Pb, Hg and Cr, but also

Toxicity to animals (Cd, Pb, Hg and Cr, but also Se, As, Mo and F) Se, As, Mo and F) -

• food chain implications

food chain implications

• Toxicity to soil micro

Toxicity to soil micro-

• organisms (Zn, Cu and Cd)
• rganisms (Zn, Cu and Cd)
• soil fertility implications

soil fertility implications

Changes in Heavy Metal Changes in Heavy Metal Content of Sludge Used on Land Content of Sludge Used on Land

Heavy Metals: Knowledge Heavy Metals: Knowledge

• Relationships between soil type, heavy metal

Relationships between soil type, heavy metal concentration and crop uptake well understood concentration and crop uptake well understood

• No adverse implications to human food chain

No adverse implications to human food chain (most exposed individual scenario) (most exposed individual scenario)

• Addition of most sludges limited by Zn or Cu

Addition of most sludges limited by Zn or Cu therefore no zootoxicity risk therefore no zootoxicity risk

• Theoretical exposure via direct animal ingestion

Theoretical exposure via direct animal ingestion that could exceed offal limit values that could exceed offal limit values

• Effects on soil fertility equivocal

Effects on soil fertility equivocal

Dietary Intake of Cadmium Dietary Intake of Cadmium

Worst case scenario: sandy soil at 3 mg Cd/kg Worst case scenario: sandy soil at 3 mg Cd/kg

Daily intake at max. soil limit for Cd: 34 µg Cd/day Tolerable daily intake (WHO): 70 µg Cd/day

12.9 8.8 6.66 0.68 1.01 3.7

Root vegetables Potatoes Bread & cereals Leafy salads Cabbage & legumes Non-impacted foods

Organics Organics: Concerns

: Concerns

• Wide range of synthetic compounds found in

Wide range of synthetic compounds found in sludge, usually at trace concentrations sludge, usually at trace concentrations

• Some recalcitrant compounds of general

Some recalcitrant compounds of general concern could accumulate in soil (PCBs, dioxins) concern could accumulate in soil (PCBs, dioxins)

• Some compounds exhibit oestrogenic effects

Some compounds exhibit oestrogenic effects

• Poor agreement internationally on target

Poor agreement internationally on target compounds and limit values compounds and limit values

• Risks of transfer to human food chain from dairy

Risks of transfer to human food chain from dairy animals grazing surface treated pasture animals grazing surface treated pasture

Organics: Organics: Knowledge

Knowledge

• Many compounds are volatile and/or readily

Many compounds are volatile and/or readily degradable in soil degradable in soil

• Recalcitrant compounds in very low

Recalcitrant compounds in very low concentrations concentrations

• All are hydrophobic except surfactants which

All are hydrophobic except surfactants which

• ccur at greatest concentrations
• ccur at greatest concentrations
• No plant uptake although surface absorption

No plant uptake although surface absorption may occur may occur

• Little evidence that organics in sludge

Little evidence that organics in sludge represents risk to environment or human health represents risk to environment or human health

Concentrations and Properties Concentrations and Properties

• f Organics of Concern
• f Organics of Concern

Type Content Degradation Leaching Volatility LAS 50 mg/kg – 1.5 % Few d Low No NPE 100-3000 mg/kg <10 d Low No Phthalates 1-100 mg/kg ½ life <50 d Low No PAHs 1-10 mg/kg Wks - 10 y Low Some PCBs 1-20 mg/kg Years Low Some PCDD/Fs ng/kg Years Low Some

Sludge Quality Sludge Quality -

• Dioxin

Dioxin

50 100 150 200 250 300 350 400 450 1944 1949 1953 1956 1958 1960 1998

Year Total TEQ (ng/kg ds) Archived sludge samples - Mogden WWTP, UK

Animal Ingestion Pathway Animal Ingestion Pathway

• Ingestion of surface

Ingestion of surface-

• applied sludge adhering to

applied sludge adhering to grass critical route of dietary exposure grass critical route of dietary exposure

• Persistent lipophilics transfer via milk and meat

Persistent lipophilics transfer via milk and meat

• No evidence that food quality impaired

No evidence that food quality impaired

• Sludge injection eliminates risk

Sludge injection eliminates risk

• 25% of sludge was surface applied in UK

25% of sludge was surface applied in UK

• Ban on surface spreading to grazed land has

Ban on surface spreading to grazed land has effectively closed this exposure pathway effectively closed this exposure pathway

Ecotoxicological Effects Ecotoxicological Effects

• Rapid degradation of bioactive compounds

Rapid degradation of bioactive compounds

• Act as substrates for microbial growth

Act as substrates for microbial growth

• Inconsistent approach to soil protection relative

Inconsistent approach to soil protection relative to to ‘ ‘acceptable acceptable’ ’ use of pesticides: use of pesticides:

– – <1% of agricultural land receives sludge <1% of agricultural land receives sludge – – Most agricultural land receives pesticides Most agricultural land receives pesticides – – Fungicides, herbicides have potent biocidal effects on Fungicides, herbicides have potent biocidal effects on soil ecological processes soil ecological processes – – Sludge application increases soil fertility Sludge application increases soil fertility

US EPA Decision to Delete US EPA Decision to Delete Organics from 503 Rule Organics from 503 Rule

• Organics deleted on basis that:

Organics deleted on basis that:

– – Pollutant is banned or has restricted use in US; Pollutant is banned or has restricted use in US; or

• r

– – Low frequency of detection ( Low frequency of detection (≤ ≤5 % of samples); 5 % of samples); or

• r

– – Risk derived limit >99%ile concentration Risk derived limit >99%ile concentration

• Risk assessment evaluated 200 pollutants and

Risk assessment evaluated 200 pollutants and 14 exposure pathways 14 exposure pathways

• Pathway 5: Sludge

Pathway 5: Sludge -

• Soil

Soil -

• Animal

Animal -

• Human

Human

• Lifetime (70 y) daily intake of tissues from

Lifetime (70 y) daily intake of tissues from grazing animals that ingest sewage sludge grazing animals that ingest sewage sludge

Pathogens: Pathogens: Concerns

Concerns

• Sludge applied to food crops represent a

Sludge applied to food crops represent a potential risk of disease transmission potential risk of disease transmission

• Wide range of pathogens and parasites may be

Wide range of pathogens and parasites may be present (viruses, bacteria, protozoa, cestodes, present (viruses, bacteria, protozoa, cestodes, nematodes) nematodes)

• Occurrence in sludge depends on general health

Occurrence in sludge depends on general health

• f population, presence of abattoirs, etc.
• f population, presence of abattoirs, etc.
• High public and retailer concern due to social

High public and retailer concern due to social constraints and recent food scares constraints and recent food scares

Pathogens: Pathogens: Knowledge

Knowledge

• Low occurrence in sludge but sensitive issue

Low occurrence in sludge but sensitive issue

• Sludge treatment conditions to reduce or eliminate

Sludge treatment conditions to reduce or eliminate pathogens pathogens

• Dual barrier (treatment and land use) is effective,

Dual barrier (treatment and land use) is effective, even for raw sludge even for raw sludge

• Target organisms (

Target organisms (Salmonella Salmonella sp and sp and T. saginata

• T. saginata)

)

• ‘

‘Emerging Emerging’ ’ pathogens ( pathogens (E. coli

• E. coli 0157,

0157, S. typhimurium

• S. typhimurium

DT 104 DT 104 etc) etc)

• Limited knowledge on viruses

Limited knowledge on viruses

Taenia saginata Salmonella

Process Conditions to Process Conditions to Reduce Pathogens Reduce Pathogens

Treatment Requirements Treatment Requirements

EC Directive EC Directive

• Biological, chemical or heat treatment, long

Biological, chemical or heat treatment, long-

• term

term storage or any other appropriate process so as storage or any other appropriate process so as significantly to reduce its fermentability and the significantly to reduce its fermentability and the health hazards resulting from its use health hazards resulting from its use US EPA Rule 503 US EPA Rule 503

• Clearly defined vector attraction reduction criteria

Clearly defined vector attraction reduction criteria

• PFRP

PFRP -

• Class A

Class A – – unrestricted use unrestricted use

• PSRP

PSRP -

• Class B

Class B – – restricted use restricted use UK UK

• Conventional and Enhanced treatment

Conventional and Enhanced treatment

Safe Sludge Matrix Safe Sludge Matrix

Agreement between Water UK and the British Retail Consortium (Dec 1998)

Sludge Treatment Sludge Treatment (UK)

(UK)

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 1990/1 1996/7 2000/1 2005/6

None Other - lesser or uncertain Thermal drying Dew atering & storage Liquid storage 3 months Lime stabilization Composting MAD & dew atering & storage Mesophilic anaerobic digestion Pasteurisation

Process

Nutrients: Concerns Nutrients: Concerns

• Leaching of nitrate and potential risks to surface

Leaching of nitrate and potential risks to surface and groundwaters and groundwaters

• Emissions of ammonia and nitrous oxide

Emissions of ammonia and nitrous oxide

• Accumulation of phosphate in soil and risks to

Accumulation of phosphate in soil and risks to surface waters surface waters

Crop uptake Nitrate leaching

Nutrients: Knowledge Nutrients: Knowledge

• Mineralisation characteristics of sludge types

Mineralisation characteristics of sludge types

• Fertiliser value of sludge types to crops

Fertiliser value of sludge types to crops

• Sludge N less liable to leaching risks than

Sludge N less liable to leaching risks than conventional fertiliser N conventional fertiliser N

• Method and timing of application to minimise losses

Method and timing of application to minimise losses

• P accumulation controllable by considering

P accumulation controllable by considering additions on a crop rotation basis additions on a crop rotation basis

• Advice to farmers on fertiliser replacement

Advice to farmers on fertiliser replacement value minimises losses value minimises losses

• Compliance with farm nutrient budgets,

Compliance with farm nutrient budgets, NVZs NVZs

Nutrient Availability Nutrient Availability

Sludge type %ds N P2O5 K2O Liquid raw 35 50 100 Liquid digested 60

(100+15)

50 100 Raw cake 20 50 100 Digested cake 15 50 100

Sludge Application Sludge Application

Objectives Objectives

• Avoid environmental problems

Avoid environmental problems

• Provide service to farmers

Provide service to farmers

• Be cost

Be cost-

• effective

effective Equipment Design Developments Equipment Design Developments

• Reduce volatile emissions

Reduce volatile emissions

• Increase agronomic value

Increase agronomic value

• Improve accuracy of application

Improve accuracy of application

• Greater operational efficiency

Greater operational efficiency

Alternative Uses for Sludge Alternative Uses for Sludge

• Land reclamation

Land reclamation

• Forestry

Forestry

• Soil manufacture

Soil manufacture

• Growing media

Growing media

• Materials recovery

Materials recovery

Land Reclamation Land Reclamation

• Well proven benefits in achieving

Well proven benefits in achieving sustainable revegetation sustainable revegetation

• One

One-

• off high rates of application
• ff high rates of application

(50 (50-

• 100 tds/ha)

100 tds/ha)

• Local and diminishing opportunities

Local and diminishing opportunities

Forestry Forestry

• Significant benefits to tree

Significant benefits to tree survival and growth survival and growth

• Local opportunities

Local opportunities

• Not suitable for natural forest

Not suitable for natural forest

Resource Recovery Resource Recovery

• Additive to animal feed

Additive to animal feed

• Recovery of valuable constituents

Recovery of valuable constituents -

• fat, protein,

fat, protein, grease, vitamin B12, metals, phosphate grease, vitamin B12, metals, phosphate

• Production of commodities

Production of commodities -

• activated carbon,

activated carbon, fibre, building materials: fibre, building materials:

• sludge

sludge -

• bricks, fibre board

bricks, fibre board

• ash

ash -

• lightweight blocks, vitrified tiles, etc.

lightweight blocks, vitrified tiles, etc.

• slag

slag -

• coarse ballast

coarse ballast

• Horticultural products

Horticultural products

• compost, thermally

compost, thermally dried pellets dried pellets

Energy Recovery Energy Recovery

• Dedicated incineration

Dedicated incineration

• Co

Co-

• combustion in power stations, waste

combustion in power stations, waste incinerators, cement production incinerators, cement production

• Oil recovery

Oil recovery

• EU Emissions

EU Emissions Trading Scheme Trading Scheme

• EC proposal:

EC proposal: 20 20 by 2020 20 20 by 2020

Sludge Disposal in EU Sludge Disposal in EU

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 1984 1992 2000 2005 Year million t dry solids/y

Recycling Combustion Disposal

Legacy of COST 68/681 Legacy of COST 68/681

• COST 68/681 was regarded by EC as one of the

COST 68/681 was regarded by EC as one of the most successful of the COST program most successful of the COST program

• Generated a large number of publications

Generated a large number of publications

• Achieved wide collaboration across Europe and

Achieved wide collaboration across Europe and beyond, between institutions and networks beyond, between institutions and networks

• Provided substantial scientific information to

Provided substantial scientific information to support sludge control measures support sludge control measures

• But, ultimately had little or no effect on:

But, ultimately had little or no effect on:

– – Development of Sludge to Land Directive and more Development of Sludge to Land Directive and more recent considerations for its revision recent considerations for its revision – – Development of integrated control of all organic wastes Development of integrated control of all organic wastes

Organic Wastes in EU Organic Wastes in EU

MSW 27% Industry 2% Sewage sludge 3% Food 4% Livestock 64%

• No integrated control of use of organic wastes

No integrated control of use of organic wastes

• Sludge use on land

Sludge use on land -

• liability for other wastes

liability for other wastes

Sewage sludge 2.4 M tds/y Livestock manure 154 M tds/y

Phosphatic fertiliser 4.2 M tds/y

(mg/kg) (t/y) (mg/kg) (t/y)

(mg/kg) (t/y)

Zn 1,000 2,400 620 95,480

• Cu

380 910 155 13,870

• Cd

4.2 10

• 43

180

Sewage sludge 2.4 M tds/y Livestock manure 154 M tds/y

Phosphatic fertiliser 4.2 M tds/y

(mg/kg) (t/y) (mg/kg) (t/y)

(mg/kg) (t/y)

Zn 1,000 2,400 620 95,480

• Cu

380 910 155 13,870

• Cd

4.2 10

• 43

180

Current / Future Issues Current / Future Issues

• Phosphate recovery

Phosphate recovery

• Energy recovery

Energy recovery

• Organic micropollutants

Organic micropollutants

• Soil conservation and protection

Soil conservation and protection

• ‘

‘New New’ ’ pathogens pathogens

• New treatment processes

New treatment processes

• Stakeholders

Stakeholders -

• retailers

retailers

• Quality assurance

Quality assurance

• Standards based on risk assessment

Standards based on risk assessment

• Common standards for all organic wastes

Common standards for all organic wastes