Regulatory Decision 111: Treating, storing, and using carbon dioxide from anaerobic digestion

This Regulatory Decision (RD) is valid until 31 May 2026 by which time it will be reviewed. You should check back at that time to ensure the Regulatory Decision is still valid.

NRW can withdraw or amend this regulatory decision before the review date if we consider it necessary. This includes where the activity that this RD relates to has not changed.

Regulatory Decision

This regulatory decision applies if you:

• capture CO2 produced from upgrading biogas to biomethane at your AD plant
• treat and store CO2 at your AD plant or elsewhere, to meet food and beverage or industrial grade standards

This RD only applies to Anaerobic Digestion facilities. You may still need other permits for other activities you carry out.

Conditions you must comply with 

You must:

• produce CO2 to food and beverage or industrial grade standards using one or more of the following techniques:

• • filtering
  • washing
  • distillation
  • compressing
  • condensation
  • drying
  • cooling

• produce CO2 that meets or will meet food and beverage or industrial grade standards
• show that you have a contract in place for the purchase of your CO2 product
• follow HSE guidance: general hazards of carbon dioxide
• record the amount of CO2 produced and stored on site
• achieve a CO2 capture rate of at least 80%
• keep records for 2 years to show that you have complied with this RD and make these records available to the Natural Resources Wales on request

You must not:

• store more than 150 tonnes of CO2 at any one time
• store CO2 for longer than 6 months before use

This decision does not apply to:

• CO2 separation and treatment techniques other than those listed above, e.g. Liquid absorption techniques using chemicals such as amines
  
  

Enforcement

This RD does not change your legal requirement to comply with an environmental permit for a waste operation. This RD applies to the activity specified only.

However, NRW will not normally take enforcement action if you do not comply with the need for an environmental permit for the activity specified and if you meet the requirements in this RD.

In addition your activity must not cause (or be likely to cause) pollution of the environment or harm to human health, and must not:

• cause a risk to water, air, soil, plants or animals
• cause a nuisance through noise or odours
• adversely affect the countryside or places of special interest