Using Digestate

Using Digestate Print E-mail

Here you will find information on regulations concerning anaerobic digestion projects.

Use the tabs at the top of the page to see regulatory information specific to England and Wales, Scotland or Northern Ireland.


England and Wales


Digestate can be used as a replacement for mineral fertilisers, reducing costs to farmers and minimising greenhouse gas emissions from cultivation. Detailed guidance on digestate in agriculture can be found on the WRAP website, this includes information on the four-year Digestate & Compost in Agriculture Project, which looks at the use of quality anaerobic digestate and compost in agriculture.

Where can digestate go?

Before investing in AD it is important to consider where and how the digestate will be used.  If it is not to be considered waste (and thus lead to a considerable administrative burden), digestate must meet the standards set out in the Quality Protocol and PAS110. The standards include a list of biowastes that can be included in AD for the producer to still meet the necessary standards. The following page provides information on producing certified quality digestate.

There must be enough land in the vicinity of the digester that can accept the digestate within the restrictions of Nitrate Vulnerable Zones (NVZs), 62% of land in England and 4% in Wales falls within NVZs.  If haulage and/or storage costs are prohibitive, there could be alternative routes like composting or using a sewage treatment works.

To work out the amount of land required to accommodate the digestate you produce, see the AD calculator. For information on how the NVZ rules and calculations apply to digestate, see section C9 of this Environment Agency Q and A. For more advice on Nitrate Vulnerable Zones (NVZs), see these pages from the Defra website.

Digestate enhancement and treatment techniques

WRAP have produced a study which identifies digestate enhancement and treatment techniques. The study considers well established techniques, as well as novel or emerging processes currently under development. The project reviews technologies applicable to all digestates produced from the anaerobic digestion of a variety of feedstocks, whether or not they are compliant with PAS110 or the Anaerobic Digestion Quality Protocol (ADQP).


Whole digestate versus separation

Digestate can be used whole, spread on land with tankers or umbilical pipe lines.  Alternatively, it can be separated in to liquor and fibres, which have differing distributions of nutrients.  The liquor should contain less than 6% dry matter.  Seperated liquor can be spread more easily to growing crops.  Separated fibre can be used fresh as a soil conditioner or, after further aerobic composting to stabilise it, a material suitable for making into a compost product.

How to plan digestate use on your land

Digestate's major drawback is that it is a pre-determined mix of nutrients that cannot be altered. For more information on the use of digestate please download Defra's industry recognised nutrient planning handbook, RB209, or you can visit the Defra website for advice on good agricultural practice for nutrients and fertilisers. 

Return to the top of the page.


Scotland


Digestate can be used as a replacement for mineral fertilisers, reducing costs to farmers and minimising greenhouse gas emissions from cultivation. Detailed guidance on digestate in agriculture can be found on the WRAP website, this includes information on the four-year Digestate & Compost in Agriculture Project, which looks at the use of quality anaerobic digestate and compost in agriculture.

Where can digestate go?

Before investing in AD it is important to consider where and how the digestate will be used.  If it is not to be considered waste (and thus lead to a considerable administrative burden), digestate must be produced in accordance with PAS110 and the SEPA position statement. It should be noted that there are certain crops or areas of land to which digestate should not be applied; it is important to check with current or potential buyers of farm produce beforehand, to ensure they approve the use of such material. The following page provides information on producing certified quality digestate.

There must be enough land in the vicinity of the digester that can accept the digestate within the restrictions of Nitrate Vulnerable Zones (NVZs), 15% of land in Scotland falls within NVZs.  If haulage and/or storage costs are prohibitive, there could be alternative routes like composting or using a sewage treatment works.

To work out the amount of land required to accommodate the digestate you produce, see the AD calculator. For more advice on Nitrate Vulnerable Zones (NVZs), see the Scottish Governments website.

Digestate enhancement and treatment techniques

WRAP have produced a study which identifies digestate enhancement and treatment techniques. The study considers well established techniques, as well as novel or emerging processes currently under development. The project reviews technologies applicable to all digestates produced from the anaerobic digestion of a variety of feedstocks, whether or not they are compliant with PAS110 or the Anaerobic Digestion Quality Protocol (ADQP).


Whole digestate versus separation

Digestate can be used whole, spread on land with tankers or umbilical pipe lines. Alternatively, it can be separated in to liquor and fibres, which have differing distributions of nutrients. The liquor should contain less than 6% dry matter. Seperated liquor can be spread more easily to growing crops. Separated fibre can be used fresh as a soil conditioner or, after further aerobic composting to stabilise it, a material suitable for making into a compost product.

How to plan digestate use on your land

Digestate's major drawback is that it is a pre-determined mix of nutrients that cannot be altered. For more information on the use of digestate please download Defra's industry recognised nutrient planning handbook, RB209, or you can visit the Defra website for advice on good agricultural practice for nutrients and fertilisers. 

Return to the top of the page.

 

Northern Ireland


Digestate can be used as a replacement for mineral fertilisers, reducing costs to farmers and minimising greenhouse gas emissions from cultivation.

Where can digestate go?

Before investing in AD it is important to consider where and how the digestate will be used. If it is not to be considered waste (and thus lead to a considerable administrative burden), digestate must meet the standards set out in the Quality Protocol and PAS110. The standards include a list of biowastes that can be included in AD for the producer to still meet the necessary standards. The following page provides information on producing certified quality digestate.

There must be enough land in the vicinity of the digester that can accept the digestate within the restrictions of Nitrate Vulnerable Zones (NVZs). If haulage and/or storage costs are prohibitive, there could be alternative routes like composting or using a sewage treatment works.

To work out the amount of land required to accommodate the digestate you produce, see the AD calculator. For information on how the NVZ rules and calculations apply to digestate, see section C9 of this Environment Agency Q and A. For more advice on Nitrate Vulnerable Zones (NVZs), see these pages from the Defra website.

Digestate enhancement and treatment techniques

WRAP have produced a study which identifies digestate enhancement and treatment techniques. The study considers well established techniques, as well as novel or emerging processes currently under development. The project reviews technologies applicable to all digestates produced from the anaerobic digestion of a variety of feedstocks, whether or not they are compliant with PAS110 or the Anaerobic Digestion Quality Protocol (ADQP).


Whole digestate versus separation

Digestate can be used whole, spread on land with tankers or umbilical pipe lines. Alternatively, it can be separated in to liquor and fibres, which have differing distributions of nutrients. The liquor should contain less than 6% dry matter. Seperated liquor can be spread more easily to growing crops. Separated fibre can be used fresh as a soil conditioner or, after further aerobic composting to stabilise it, a material suitable for making into a compost product.

How to plan digestate use on your land

Digestate's major drawback is that it is a pre-determined mix of nutrients that cannot be altered. For more information on the use of digestate please download Defra's industry recognised nutrient planning handbook, RB209, or you can visit the Defra website for advice on good agricultural practice for nutrients and fertilisers. 

Return to the top of the page.