10 Waste codes
10 wastes are from thermal processes. Your permit lists the 10 waste codes you can use. You must follow the guidance given in the Before you start section.
10 01 wastes are from power stations and other combustion plants.
10 01 01 Poultry litter ash, paper sludge ash and ash from wood chip boilers only
You can use this waste if you hold SR2010 No 4 – see table 2.2B.
It includes these types of ash:
- poultry litter ash
- paper sludge ash
- ash from woodchip boilers only
In your deployment application use the waste code and description 10 01 01 Poultry litter ash, paper sludge ash and ash from wood chip boilers only. State if it is poultry litter ash, paper sludge ash or ash from woodchip boilers only.
You must follow the guidance given under Manage ash.
Manage ash
For landspreading purposes ash is the term given to incineration products from the burning of biodegradable materials only.
You must not spread ash from burning non-biodegradable waste under the standard rules permits.
You will need to:
- know the source and type of the ash to determine the potential contaminants and sampling requirements
- describe and identify each ash waste stream separately
- justify that the ash can give benefit in its own right
You must not mix these waste streams before characterisation and sampling
These are the 4 types of ash.
Fly ash
Fly ash is a pollution control residue. This is the ash that rises with the flue gases and is collected through abatement measures such as cyclones to reduce the particulate matter released to the environment.
Bag ash
Bag ash is a pollution control residue. The incineration process often uses abatement measures to reduce chemical contaminants such as oxides of nitrogen released into the atmosphere from flue gases. These can be treated by adding ammonia or urea to the flue gas if required and may result in bag ash and other types of gas cleaning residues production.
Bottom or incinerator bottom ash
Bottom or incinerator bottom ash sinks to the bottom and is discharged into the burning grate.
Boiler dust
Boiler dust is the dust collected within the incinerator.
Typical element composition of ash from some biomass fuels
| Element | Coniferous forestry residue | Short rotation cropping willow | Cereal straw | Oil seed rape straw | Miscanthus | Reed canary grass |
|---|---|---|---|---|---|---|
| Sulphur %w/w Dry ash free basis |
0.04 | 0.05 | 0.1 | 0.3 | 0.2 | 0.2 |
| Chlorine %w/w Dry ash free basis |
0.01 | 0.03 | 0.4 | 0.5 | 0.2 | 0.2 |
| Aluminium (mg/kg Dry Matter (DM)) |
- | - | 50 | 50 | - | - |
| Calcium (mg/kg DM) |
5,000 | 5,000 | 4,000 | 15,000 | 2,000 | 3,500 |
| Iron (mg/kg DM) |
- | 100 | 100 | 100 | 100 | - |
| Potassium (mg/kg DM) |
2,000 | 3,000 | 10,000 | 10,000 | 7,000 | 12,000 |
| Magnesium (mg/kg DM) |
800 | 500 | 700 | 700 | 600 | 1,300 |
| Sodium (mg/kg DM) |
200 | - | 500 | 500 | - | 200 |
| Phosphorus (mg/kg DM) |
500 | 800 | 1000 | 1,000 | 700 | 1,700 |
| Silicon (mg/kg DM) |
3,000 | - | 10,000 | 1,000 | - | 12,000 |
Source: Biomass ash characteristics and behaviour in combustion, gasification and pyrolysis systems by W R Livingston.
Poultry litter ash
Poultry litter mainly from rearing chicken for meat can be used as a feedstock for power stations. The material consists mainly of wood shavings, poultry manure, feathers and straw. You can spread this ash to land under the waste code and description 10 01 01 Poultry litter ash, paper sludge ash and ash from wood chip boilers only.
You must be able to comply with the requirements of the
You can spread poultry litter ash to land as a non-waste outside of environmental permitting controls. You must be able to comply with the requirements of Quality protocol: poultry litter ash.
If the poultry litter ash does not meet the requirements of the quality protocol: poultry litter ash then it remains a waste and can only be spread to land under SR2010 No 4.
You must not accept ash produced from other wastes not included in the quality protocol. For example, you cannot use ash from treated wood under SR2010 No 4.
You can spread ash to land under SR2010 No 4 that fails to meet the quality protocol. For example, because it exceeds metals thresholds. However, you must provide a site-specific assessment in your benefit statement for the proposed ash application.
You must also follow the guidance given in manage ash.
Benefits and risks
Consider these benefits. It can provide:
- phosphate and potash in readily available forms
- a source of calcium and magnesium with a neutralising value of typically 14%
- useful amounts of sulphur and sodium
- trace nutrients such as copper, cobalt, boron, manganese, zinc and iodine
Consider these risks. The ash can:
- be difficult to handle due to its dusty nature
- irritate the skin and eyes
- contain variable levels of potentially toxic elements and dioxins
Potentially toxic elements and the limits that must be met are given in the Sewage sludge in agriculture: code of practice. These limits apply to this waste not just sewage sludge.
You can use water to dampen fine ash. This may:
- reduce landspreading accuracy as the ash will tend to form lumps
- coat machinery such as spinning discs and the moving floor mechanisms of spreaders
Paper sludge ash
Paper sludge ash is the waste product from recycling paper at paper mills. Paper sludge is a combination of short cellulose fibres, water, ink, soap and other minerals such as kaolin, carbonates and talc separated from the recovered paper feedstock.
Paper sludge ash is a residue from incinerating paper sludge and other input materials from recycling newspaper-related products.
You must follow the guidance given in manage ash.
Benefits and risks
Consider these benefits:
- it has beneficial liming value, although the neutralising value can vary depending on the source and moisture content of the waste
- it can contain small amounts of potash and phosphate – however the benefit from these nutrients may be negligible because the liming value will determine the application rate
- fly ash contains a mixture of calcium and magnesium compounds which can adjust soil pH levels
Consider these risks. It may:
- contain residues from the combustion materials
- contain potentially toxic elements and other contaminants
- produce very fine dust when spread which may harm human health or cause nuisance
- be classified as hazardous waste if it has any of the hazardous properties HP1 to HP14 given in Waste classification technical guidance (WM3)
Potentially toxic elements and the limits that must be met are given in the Sewage sludge in agriculture: code of practice. These limits apply to this waste not just sewage sludge.
The rate you can apply paper sludge ash to the land depends on the need for agricultural lime. Base this on the:
- cropping requirement
- receiving soil type
- current soil pH and intended target soil pH
The neutralising value of paper sludge ash is typically 37% or higher calcium carbonate. Apply this to land accordingly based on the neutralising value.
Ash from woodchip boilers only
This is also called biomass fuel.
Wood ash is the inorganic and organic residue that remains after combusting wood or unbleached wood fibre and plant tissue waste.
The physical and chemical properties of wood ash vary significantly. This depends on the feedstock and incineration process. Hardwoods usually produce more ash than softwoods. Bark and leaves generally produce more ash than the inner woody parts of the tree. Wood ash composition varies highly depending on where the wood was originally from.
You must follow the guidance given in manage ash.
Benefits and risks
Consider these benefits. It can:
- have a high calcium content which may provide liming benefit – wood ash has a pH in the range of 8.0 to 12.0
- be a source of nitrogen, phosphorus, potassium, magnesium and aluminium; average wood ash is generally in the ratio of 0 to 1 to 3 (nitrogen-phosphorus-potassium)
- have trace nutrients such as boron and sodium
- contribute to soil organic carbon
- be used to condition soil
Wood ash contains the charred remains of plants and is similar to biochar which is the charcoal-like residue left following pyrolysis of organic plant material. This can provide:
- cation exchange sites and soil organic carbon
- moisture retention
Consider these risks:
- it can be dusty and difficult to handle
- can contain variable levels of potentially toxic elements or other contaminants
Potentially toxic elements and the limits that must be met are given in the Sewage sludge in agriculture: code of practice. These limits apply to this waste not just sewage sludge.
You can use water to dampen fine ash. This may:
- reduce landspreading accuracy as the ash will tend to form lumps
- coat machinery such as spinning discs and the moving floor mechanisms of spreaders
- irritate the skin and eyes
You must consider organic chemical contaminant content in the ash. This will depend on the use of other feedstocks. For example, if the biomass is co-fired with treated timber wastes. You must provide details in your benefit statement of the:
- input materials
- fuel and combustion process
10 01 01 Meat and bone meal ash
You can use this waste if you hold SR2010 No 4 – see table 2.2B.
For this waste you must follow the information for 19 01 12 Ash from the incineration of pig and poultry carcasses at premises used for agriculture only.
10 01 05 Flue gas gypsum (solid) only and 10 01 07 flue gas gypsum (sludge) only
You can use these wastes if you hold:
- SR2010 No 4 – see table 2.2B
- SR2010 No 5 – see table 2.2
You must follow the information given for flue gas desulphurisation gypsum.
Flue gas desulphurisation gypsum
Flue gas desulphurisation gypsum is related to coal fired power stations fitted with flue gas desulphurisation equipment. The equipment uses limestone to remove sulphur dioxide and up to 95% of the hydrogen chloride from the flue gas. The chemical reactions in the flue gas desulphurisation units converts the limestone into gypsum.
Currently most of the gypsum produced by flue gas desulphurisation in power stations is used in manufacturing plasterboard.
Gypsum produced for reprocessing plasterboard may enter the landspreading cycle as recycled gypsum from plasterboard. Subsequently, if you are using this waste code you must see 19 12 12 Recycled gypsum from plasterboard.
10 13 wastes are from the manufacture of cement, lime and plaster and articles and products made from them.
Spreading lime dust, cement kiln dust and by-pass dust near sensitive receptors
These wastes can be dusty and cause a hazard to human health and environmental receptors. You must not endanger human health or harm the environment.
You must:
- avoid landspreading lime dust, cement kiln dust and by-pass dust near sensitive receptors
- identify these receptors in your benefit statement, including neighbouring off-site receptors
The risks are greater if the wind is blowing towards a sensitive receptor. For example, towards people or pH sensitive plants.
To reduce the risk of harm from windblown cement kiln dust and by-pass dust you can use pre-conditioned waste. The waste producer can supply this waste. They condition it with water, making it a granular material. You may find this easier to handle and spread. If it is supplied pre-conditioned, use waste codes:
- 19 02 03 cement kiln dust and by-pass dust from cement kilns conditioned with water only
- 19 02 04* cement kiln dust and by-pass dust from cement kilns conditioned with water only
Note that 19 02 04* even if pre-conditioned is still a hazardous waste.
10 13 04 wastes from calcinations and hydration of lime
You can use this waste if you hold:
- SR2010 No 4 – see table 2.2B
- SR2010 No 5 – see table 2.2
This waste is commonly called lime dust and is collected from filtration of the kiln exhaust gases.
In your deployment application use the waste code and description 10 13 04 Wastes from calcinations and hydration of lime. State that it is lime dust.
Lime dust
Lime dust is a waste produced from processing limestone (calcium carbonate) to make lime products like:
- quicklime (calcium oxide) – the limestone is crushed and heated in a kiln
- slaked lime (calcium hydroxide) – the manufacturer adds water to quicklime
These are then sold commercially for a variety of uses in the form of:
- a slurry
- milk of lime
- a powder
You can potentially landspread lime dust waste under SR2010 No 4 or SR2010 No 5. The material is physically very similar to the commercial lime dust used in agriculture.
The heating temperature can vary from moderately low up to 1,800°C. This depends on the reactivity and physical properties needed for the final product. The most common heating fuel is gas. However, manufacturers may have used secondary fuels made from high-calorific wastes such as solvents, tyres, processed municipal waste or oils in the heating process. This can result in an increase of contaminants in the waste. You must consider this in your waste analysis.
Benefits and risks
Lime dust has a liming benefit.
Consider these risks:
- due to its dusty nature it may cause nuisance when handled and spread
- it may contain metals and other contaminants
- over-liming can reduce trace elements in the receiving soil
- dust from landspreading can cause harm to nearby sensitive receptors such as adjacent hedgerows or grassland
The lime dust may have a high metal content. For example, it may be high in lead due to:
- the use of secondary fuels
- it being in the source rock from lead-rich mineral veins within the quarried limestone and shale used in the process
You must follow the information given in spreading lime dust, cement kiln dust and by-pass dust near sensitive receptors.
See also the information given for gypsum.
Application rates
If your waste analysis for contaminants is acceptable, you can apply the waste at a rate based on the:
- neutralising value of the waste
- lime requirement of the receiving soil
Its neutralising value is around 45 to 55% calcium carbonate which can be lower than standard agricultural lime which is 50 to 55%. You can apply lime dust at higher application rates to compensate.
For more details see soil acidity and liming in RB209.
10 13 12* Cement kiln dusts and by-pass dust only
You can use this waste if you hold:
- SR2010 No 4 – see table 2.2B
- SR2010 No 5 – see table 2.2
By-pass dust can be a hazardous waste you must follow Accepting hazardous waste in Landspreading: how to comply with your permit under 2.2 Waste acceptance.
Cement kiln dust and by-pass dust
These wastes are from the calcination and hydration of lime in cement manufacturing. The main process wastes are cement kiln dust and by-pass dust.
You can spread cement kiln dust and by-pass dust wastes to land under SR2010 No 4 or SR2010 No 6. They are forms of kiln dust from pollution control residues from treating kiln gas streams. The main difference between cement kiln dust and by-pass dust is the point of production and the degree of calcination (free lime content).
In comparison with agricultural lime, cement kiln dust and by-pass dust are very fine grained materials. This will provide a large surface area that will rapidly react with the soil. Agricultural lime takes approximately 1 to 2 years to finish reacting with the soil.
These wastes can also affect sensitive receptors when you store and spread them. You must follow the information given in spreading lime dust, cement kiln dust and by-pass dust near sensitive receptors.
Cement kiln dust
Cement kiln dust is produced in kilns that do not have a bypass system. Examples include wet kilns, long dry kilns, Lepol grate kilns and older generation preheater and precalciner systems.
Cement kiln dust is collected from processing the raw materials used to manufacture cement clinker. Approximately 80% of it is made up of chalk. The calcination of the chalk is one of the main stages in the process. Therefore, the cement kiln dust is largely made up of calcined chalk picked up in the gas stream. The dust contains a higher proportion of calcium carbonate, and in some cases larger particles, because it is taken out of the kiln when the temperature is lower.
By-pass dust
The cement industry refers to dust by-pass dust when it is produced from the abatement process as part of the by-pass system. By-pass systems are fitted to precalciner kilns to bleed off volatile compounds in the raw materials such as alkalis. Controlling these compounds is needed to avoid build up at cooling in the preheater and to maintain clinker quality. When the raw materials go through higher temperatures there is a higher free lime content of by-pass dust (greater than 10%). The effect of temperature and calcination may mean the by-pass dust is a hazardous waste. If the waste is not a hazardous waste use the waste code and description 10 13 13 Cement kiln dusts and by-pass dust other than those mentioned in 10 13 12 only.
Benefits and risks
Consider these benefits. Cement kiln dust and by-pass dust can:
- have a liming benefit, the neutralising value can vary depending on the moisture content of the waste, but is usually in the range of 20 to 45% calcium oxide
- provide moderate amounts of potash of up to 30kg/t in some wastes
However, the benefit from the potash is negligible because the waste is usually applied to the land at low rates.
Consider these risks:
- by-pass dust can be a hazardous waste due to the effect of temperature and calcination
- possible deposits on or near pH sensitive plant species
- it contains contaminants, including metals or other contaminants – your waste and soil analysis must show it causes no environmental harm
- it usually contains residues from the combustion materials
The type and source of raw materials and the fuel used in the manufacturing process may cause contaminants in the waste. Using secondary fuel (Cemfuel) derived from high-calorific wastes such as solvents, tyres and processed municipal waste may increase metal contamination. You must analyse waste for contaminants such as metals.
Application rates
If your waste analysis for contaminants is acceptable, you can apply the waste at a rate based on the:
- neutralising value of the waste
- lime requirement of the receiving soil
Standard lime has a neutralising value of 50 to 55% calcium oxide. Cement kiln dust and by-pass dust have values of between 20 and 45%. Aim to set your application rates between half and three-quarters more than standard lime applications.
For more details see soil acidity and liming in RB209.
You must avoid over-liming. This can reduce trace elements in the receiving soil.
10 13 13 Cement kiln dusts and by-pass dust other than those mentioned in 10 13 12 only
You can use this waste if you hold:
- SR2010 No 4 – see table 2.2B
- SR2010 No 5 – see table 2.2
Follow the information given for 10 13 12* cement kiln dusts and by-pass dust only.
Using this waste code means the by-pass dust is not a hazardous waste.
10 13 99 Gypsum only
You can use this waste if you hold:
- SR2010 No 4 – see table 2.2B
- SR2010 No 5 – see table 2.2
For this waste you must follow the information for: