Schedule 12 NEW SCHEDULE 21 TO BE ADDED INTO THE 2018 REGULATIONS

“SCHEDULE 21

OPERATING A LARGE COMBUSTION PLANT

Regulation 6(1)

PART 1

Scope and interpretation

Scope and interpretation: operating a large combustion plant

1.

(1)

This schedule applies to operating a large combustion plant.

(2)

“Large combustion plant” means a combustion plant where the total rated thermal input of which is equal to or greater than 50 MW, irrespective of the type of fuel used, but does not include—

(a)

plants in which the products of combustion are used for the direct heating, drying, or any other treatment of objects or materials,

(b)

post-combustion plants designed to purify the waste gases by combustion which are not operated as independent combustion plants,

(c)

facilities for the regeneration of catalytic cracking catalysts,

(d)

facilities for the conversion of hydrogen sulphide into sulphur,

(e)

reactors used in the chemical industry,

(f)

coke battery furnaces,

(g)

cowpers,

(h)

any technical apparatus used in the propulsion of a vehicle, ship or aircraft,

(i)

gas turbines and gas engines used on offshore platforms,

(j)

plants which use any solid or liquid waste as a fuel other than waste that is biomass.

Interpretation: general

2.

In this schedule—

• “CCGT” means combined cycle gas turbines,

• “determinative fuel” means the fuel which, amongst all fuels used in a multi-fuel firing combustion plant using the distillation and conversion residues from the refining of crude oil for own consumption alone or with other fuels, has the highest emission limit value as set out in Part 3 of this schedule, or, in the case of several fuels having the same emission limit value, the fuel having the highest thermal input amongst those fuels,

• “diesel engine” means an internal combustion engine which operates according to the diesel cycle and uses compression ignition to burn fuel,

• “gas engine” means an internal combustion engine which operates according to the Otto cycle and uses spark ignition or, in the case of dual fuel engines, compression ignition to burn fuel,

• “gas turbine” means any rotating machine which converts thermal energy into mechanical work, consisting mainly of a compressor, a thermal device in which fuel is oxidised in order to heat the working fluid, and a turbine,

• “indigenous solid fuel” means a naturally occurring solid fuel fired in a combustion plant specifically designed for that fuel and extracted locally,

• “multi-fuel firing combustion plant” means any combustion plant which may be fired simultaneously or alternately by two or more types of fuel,

• “operating hours” means the time, expressed in hours, during which a combustion plant, in whole or in part, is operating and discharging emissions into the air, excluding start-up and shut-down periods,

• “rate of desulphurisation” means the ratio over a given period of time of the quantity of sulphur which is not emitted into air by a combustion plant to the quantity of sulphur contained in the solid fuel which is introduced into the combustion plant facilities and which is used in the plant over the same period of time,

• “stack” means a structure containing one or more flues providing a passage for waste gases in order to discharge them into the air.

Aggregation rules

3.

(1)

Where the waste gases of two or more separate combustion plants are discharged through a common stack—

(a)

the combination formed by such plants is to be considered a single combustion plant, and

(b)

their capacities added together for the purpose of calculating the total rated thermal input.

(2)

Where two or more separate combustion plants—

(a)

have been granted a permit for the first time on or after 1 July 1987 or in relation to which a complete application for a permit has been submitted on or after that date, and

(b)

are installed in such a way that taking technical and economic factors into account, their waste gases could, in the judgement of SEPA, be discharged through a common stack—

(i)

the combination formed by such plants is to be considered as a single combustion plant, and

(ii)

their capacities added for the purpose of calculating the total rated thermal input.

(3)

For the purpose of calculating the total rated thermal input of a combination of combustion plants referred to in sub-paragraphs (1) and (2), individual combustion plants with a rated thermal input below 15 MW are not to be considered.

PART 2

Amendments to common framework provisions

Authorisations: permits

4.

(1)

Operating a large combustion plant may only be authorised by permit.

(2)

A permit for operating a large combustion plant must not be granted unless the permit gives effect to the requirements of this schedule.

Permits: discharge of waste gases

5.

(1)

Waste gases from large combustion plants must be discharged in a controlled way by means of a stack, containing one or more flues.

(2)

The height of the stack must be calculated in such a way as to safeguard human health and the environment.

Permits: emission limit values

6.

(1)

All permits for operating a large combustion plant which have been granted before 7 January 2013, or for which a complete application was submitted before that date, provided that such plants were in operation not later than 7 January 2014 must include conditions ensuring that emissions into the air from these plants do not exceed the emission limit values set out in Chapter 1 of Part 3 of this schedule.

(2)

All permits for operating a large combustion plant other than those described in sub-paragraph (1) must include conditions ensuring that emissions into the air from these plants do not exceed the emission limit values set out in Chapter 2 of Part 3 of this schedule.

(3)

Emission limit values and minimum rates of desulphurisation apply to the emissions of each common stack in relation to the total rated thermal input of the entire large combustion plant.

(4)

Where Part 3 of this schedule provides that emission limit values may be applied for a part of a large combustion plant with a limited number of operating hours, those limit values apply to the emissions of that part of the plant, but must be set in relation to the total rated thermal input of the entire combustion plant.

(5)

Where a large combustion plant is extended, the emission limit values set out in Chapter 2 of Part 3 of this schedule—

(a)

apply to the extended part of the plant affected by the change,

(b)

must be set in relation to the total rated thermal input of the entire combustion plant.

(6)

Sub-paragraph (7) applies where there is an extension to a large combustion plant that—

(a)

may have consequences for the environment, and

(b)

affects a part of the plant with a rated thermal input of 50 MW or more.

(7)

Where this sub-paragraph applies, the emission limit values as set out in Chapter 2 of Part 3 of this schedule apply to the part of the plant referred to in sub-paragraph (5) which has changed in relation to the total rated thermal input of the entire combustion plant.

Emission limit value exemptions: general

7.

The emission limit values set out in Chapters 1 and 2 of Part 3 of this schedule do not apply to the following large combustion plants—

(a)

diesel engines,

(b)

recovery boilers within installations for the production of pulp.

Emission limit value exemptions: fuel shortages and interruptions

8.

(1)

SEPA may, on application by the authorised person, grant an exemption for a maximum of 6 months from the obligation to comply with the emission limit value for sulphur dioxide set out in Chapters 1 and 2 of Part 3 of this schedule where—

(a)

a large combustion plant normally uses low-sulphur fuel, and

(b)

the authorised person is unable to comply with those limit values because of an interruption in the supply of low-sulphur fuel resulting from a serious shortage.

(2)

SEPA may, on application by the authorised person, grant an exemption for a maximum of 10 days, unless there is an overriding need to maintain energy supplies, from the obligation to comply with emission limit values set out in Chapters 1 and 2 of Part 3 of this schedule where—

(a)

a large combustion plant normally uses only gaseous fuel,

(b)

the authorised person has to resort exceptionally to the use of other fuels because of a sudden interruption in the supply of gas, and

(c)

for this reason, would need to be equipped with a waste gas purification facility.

(3)

An application for an exemption—

(a)

under sub-paragraph (1), must be made to SEPA in writing,

(b)

under sub-paragraph (2)—

(i)

must be made immediately and in advance of the need to use other fuels,

(ii)

may be made in writing, or by other means,

(c)

will be treated as an accelerated application for a variation under regulation 63 of these Regulations,

(d)

will be determined by SEPA within the period as considered appropriate by SEPA in the circumstances.

(4)

SEPA must notify the authorised person in writing of an exemption granted under sub-paragraph (3) where practicable to do so.

(5)

SEPA must immediately inform the Scottish Ministers of any exemption granted under sub-paragraph (1) or (2).

Emission limit value exemptions: desulphurisation for combustion plants firing indigenous solid fuel

9.

(1)

SEPA may apply the minimum rates of desulphurisation set out in Chapter 5 of Part 3 of this schedule where the circumstances in sub-paragraph (2) or (3) apply.

(2)

This sub-paragraph applies to a large combustion plant that fires indigenous solid fuel, where—

(a)

due to the characteristics of that fuel, the plant cannot comply with the emission limit value for sulphur dioxide required by paragraphs 6(1) and (2) of this schedule,

(b)

the authorised person has submitted a technical report to SEPA,

(c)

SEPA has validated the technical report, and

(d)

the minimum rates of desulphurisation are applied as a monthly average limit value.

(3)

This sub-paragraph applies to a large combustion plant that fires indigenous solid fuel which co-incinerates waste, where—

(a)

due to the characteristics of that fuel, the plant cannot comply with the C_proc values for sulphur dioxide set out in paragraphs 21(4) and (5) of schedule 22, and

(b)

the minimum rates of desulphurisation are applied as a monthly average limit value.

(4)

Where the minimum rate of desulphurisation is applied in the circumstances described in sub-paragraph (2), C_waste as referred to in paragraph 19 of schedule 22 is equal to 0 mg/Nm³.

Carbon capture and storage

10.

(1)

SEPA must assess whether the following conditions are met for all large combustion plants with a rated electrical output of 300 megawatts or more, for which the first permit was granted after 25 June 2009—

(a)

suitable storage sites are available,

(b)

transport facilities are technically and economically feasible, and

(c)

it is technically and economically feasible to retrofit for carbon dioxide capture.

(2)

In assessing whether the conditions in sub-paragraph (1) are met, SEPA must also take into account other information, and in particular information concerning the protection of the environment and human health.

(3)

Where the conditions in sub-paragraph (1) are met, SEPA must include such conditions as it considers appropriate to ensure that suitable space on the authorised place is set aside for the equipment necessary to capture and compress carbon dioxide.

(4)

In this paragraph, “first permit” means a permit under either the Pollution Prevention and Control (Scotland) Regulations 2012^f1 or the Pollution Prevention and Control (Scotland) Regulations 2000^f2.

Abatement equipment malfunction or breakdown

11.

(1)

SEPA must ensure permits for operating a large combustion plant include such conditions as it considers appropriate to give effect to sub-paragraphs (a) to (c)—

(a)

in the event that normal operation is not restored within 24 hours of a break-down, the authorised person must—

(i)

reduce or stop operations, or

(ii)

operate the plant using low polluting fuels,

(b)

the authorised person must notify SEPA within 48 hours of the malfunction or breakdown of abatement equipment,

(c)

the cumulative period of unabated operation must not exceed 120 hours in any 12-month period.

(2)

SEPA may, on application by the authorised person, provide for an exemption to the time periods in sub-paragraph (1)(a) and (1)(c) where—

(a)

there is an overriding need to maintain energy supplies, or

(b)

the combustion plant with the breakdown would be replaced for a limited period by another plant which would cause an overall increase in emissions.

(3)

An application for an exemption—

(a)

under sub-paragraph (2)(a)—

(i)

must be made immediately and in advance of the need to use other fuels,

(ii)

may be made in writing, or by other means,

(b)

under sub-paragraph (2)(b), must be made to SEPA in writing,

(c)

will be treated as an accelerated application for a variation under regulation 63 of these Regulations,

(d)

will be determined by SEPA within the period as considered appropriate by SEPA in the circumstances.

(4)

SEPA will notify the authorised person in writing of an exemption granted under sub-paragraph (2) where practicable to do so.

Emissions monitoring and compliance

12.

(1)

SEPA must ensure that a permit for operating a large combustion plant includes such conditions as it considers appropriate to ensure—

(a)

monitoring of air polluting substances is carried out in accordance with Chapter 3 of Part 3 of this schedule,

(b)

installation and functioning of the automated monitoring equipment is subject to control and annual surveillance tests as set out in Chapter 3 of Part 3 of this schedule,

(c)

that the location of the sampling or measurement points to be used for emissions monitoring is as designated by SEPA,

(d)

the recording and reporting of monitoring results to SEPA,

(e)

where any of paragraphs 20(2), 21(4), 28(2), 29(3) of this schedule applies, the recording of the used operating hours,

(f)

where more than 10 days over a year are invalidated as result of paragraph 37(2) of this schedule, adequate measures are taken to improve the reliability of the automated measuring system,

(g)

where paragraph 33 of this schedule applies, that SEPA is informed of significant changes in the type of fuel used.

(2)

In assessing compliance with emission limit values SEPA must have regard to the conditions set out in Chapter 4 of Part 3 of this schedule.

Multi-fuel firing combustion plants

13.

(1)

SEPA must, except where sub-paragraph (2) applies, set the emissions limit value for a multi-fuel large combustion plant involving the simultaneous use of two or more fuels by—

(a)

taking the emission limit value for each individual fuel and pollutant corresponding to the total rated thermal input of the entire combustion plant as set out in Chapters 1 and 2 of Part 3 of this schedule,

(b)

determining fuel-weighted emission limit values, by multiplying the individual emission limit value in head (a) by the thermal input delivered by each fuel, and dividing the total by the total thermal inputs delivered by all fuels,

(c)

aggregating the fuel-weighted emission limit values.

(2)

This sub-paragraph applies to a multi-fuel large combustion plant covered by paragraph 6(1) of this schedule, which uses the distillation and conversion residues from the refining of crude oil for own consumption, alone or with other fuels.

(3)

Where sub-paragraph (2) applies, the following emission limit values may be set rather than the values set according to sub-paragraph (1)—

(a)

where, during the operation of the combustion plant, the proportion contributed by the determinative fuel to the sum of the thermal inputs delivered by all fuels is 50% or more, the emission limit value set in Chapter 1 of Part 3 of this schedule for the determinative fuel,

(b)

where the proportion contributed by the determinative fuel to the sum of the thermal inputs delivered by all fuels is less than 50%, the emission limit value is determined by—

(i)

taking the emission limit values set out in Chapter 1 of Part 3 of this schedule for each of the fuels used, corresponding to the total rated thermal input of the combustion plant,

(ii)

calculating the emission limit value of the determinative fuel by multiplying the emission limit value, determined for that fuel according to sub-head (i), by a factor of two, and subtracting from this product the emission limit value of the fuel used with the lowest emission limit value as set out in Chapter 1 of Part 3 of this schedule, corresponding to the total rated thermal input of the combustion plant,

(iii)

determining the fuel-weighted emission limit value for each fuel used by multiplying the emission limit value determined under sub-heads (i) and (ii) by the thermal input of the fuel concerned and by dividing the total by the total thermal inputs delivered by all fuels,

(iv)

aggregating the fuel-weighted emission limit values.

(4)

Where a multi-fuel firing large combustion plant to which paragraph 6(1) of this schedule applies uses the distillation and conversion residues from the refining of crude-oil for its own consumption, alone or with other fuels, the average emission limit values for sulphur dioxide set out in Chapter 6 of Part 3 of this schedule may be applied instead of the emission limit values set according to sub-paragraphs (1) or (3) of this paragraph.

Monitoring and reporting

14.

SEPA must ensure that a permit for operating a large combustion plant includes such conditions as it considers appropriate to ensure that the following information is reported to SEPA—

(a)

the total rated thermal input (MW) of the combustion plant,

(b)

the type of combustion plant—

(i)

boiler,

(ii)

gas turbine,

(iii)

gas engine,

(iv)

diesel engine,

(v)

other, with specification of the type,

(c)

the date of the start-up of operation of the combustion plant,

(d)

the total annual emissions (tonnes per year) of sulphur dioxide, nitrogen oxides and dust (as total suspended particles),

(e)

the number of operating hours of the combustion plant,

(f)

the total annual amount of energy input, related to the net calorific value (TJ per year), broken down in terms of the following categories of fuel—

(i)

coal,

(ii)

lignite,

(iii)

biomass,

(iv)

peat,

(v)

other solid fuels, with specification of type,

(vi)

liquid fuels,

(vii)

natural gas,

(viii)

other gases, with specification of type.

Start-up and shut-down periods

15.

The determination of start-up and shut-down periods for large combustion plants is to be in accordance with Commission Implementing Decision of 7 May 2012 concerning the determination of start-up and shut-down periods for the purposes of the Industrial Emissions Directive^f3.

PART 3

Technical provisions relating to combustion plants

CHAPTER 1

Emission limit values for combustion plants referred to in paragraph 6(1)

Calculation of emission limit values

16.

All emission limit values are to be calculated—

(a)

at a temperature of 273.15K,

(b)

a pressure of 101.3kPa,

(c)

after correction for the water vapour content of the waste gases, and

(d)

at a standardised O₂ content of—

(i)

6% for solid fuels,

(ii)

3% for combustion plants, other than gas turbines and gas engines using liquid and gaseous fuels,

(iii)

15% for gas turbines and gas engines.

Emission limit values for SO₂ for combustion plants using solid or liquid fuels (with the exception of gas turbines and gas engines)

17.

(1)

Emission limit values (mg/Nm³) for SO₂ for combustion plants using solid or liquid fuels with the exception of gas turbines and gas engines where the circumstances in sub-paragraphs (2) to (4) do not apply are as stated in Table 1—

Table 1

Total rated thermal input (MW)	Coal and lignite and other solid fuels	Biomass	Peat	Liquid Fuels
50-100	400	200	300	350
100-300	250	200	300	250
>300	200	200	200	200

(2)

Combustion plants, using solid fuels which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003, and which do not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, are subject to an emission limit value for SO₂ of 800 mg/Nm³.

(3)

Combustion plants using liquid fuels, which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003, and which do not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, are subject to an emission limit value for SO₂ of 850 mg/Nm³ in case of plants with a total rated thermal input not exceeding 300 MW and of 400 mg/Nm³ in case of plants with a total rated thermal input greater than 300 MW.

(4)

A part of a combustion plant discharging its waste gases through one or more separate flues within a common stack, and which does not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, may be subject to the emission limit values set out in sub-paragraphs (2) and (3) in relation to the total rated thermal input of the entire combustion plant.

(5)

Where sub-paragraph (4) applies, the emissions through each of those flues must be monitored separately.

Emission limit values for SO₂ combustion plants using gaseous fuels (with the exception of gas turbines and gas engines)

18.

(1)

Emission limit values (mg/Nm³) for SO₂ for combustion plants using gaseous fuels with the exception of gas turbines and gas engines are, unless the circumstances in sub-paragraph (2) apply, as stated in Table 2—

Table 2

In general	35
Liquefied gas	5
Low calorific gases from coke oven	400
Low calorific gases from blast furnace	200

(2)

Combustion plants, firing low calorific gases from gasification of refinery residues, which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003, are subject to an emission limit value for SO₂ of 800 mg/Nm³.

Emission limit values for NOx for combustion plants using solid or liquid fuels (with the exception of gas turbines and gas engines)

19.

(1)

Emission limit values (mg/Nm³) for NOx for combustion plants using solid or liquid fuels with the exception of gas turbines and gas engines are, unless the circumstances in sub-paragraphs (2) to (6) are as stated in Table 3—

Table 3

Total rated thermal input (MW)	Coal and lignite and other solid fuels	Biomass and Peat	Liquid fuels
(1) The emission limit value is 450 mg/Nm3 for the firing of distillation and conversion residues from the refining of crude-oil for own consumption in combustion plants with a total rated thermal input not exceeding 500 MW which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003.
500-100	300 450 in case of pulverised lignite combustion	300	450
100-300	200	250	200f4
>300	200	200	150

(2)

Combustion plants in chemical installations using liquid production residues as non-commercial fuel for own consumption with a total rated thermal input not exceeding 500 MW which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003, are subject to an emission limit value for NO_x of 450 mg/Nm³.

(3)

Combustion plants using solid or liquid fuels with a total rated thermal input not exceeding 500 MW which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003, and which do not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, are subject to an emission limit value for NO_x of 450 mg/Nm³.

(4)

Combustion plants using solid fuels with a total rated thermal input greater than 500 MW, which were granted a permit before 1 July 1987 and which do not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, are subject to an emission limit value for NO_x of 450 mg/Nm³.

(5)

Combustion plants using liquid fuels, with a total rated thermal input greater than 500 MW which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003, and which do not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, are subject to an emission limit value for NO_x of 400 mg/Nm³.

(6)

A part of a combustion plant discharging its waste gases through one or more separate flues within a common stack, and which does not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, may be subject to the emission limit values set out in sub-paragraphs (3) to (5) in relation to the total rated thermal input of the entire combustion plant.

(7)

Where sub-paragraph (6) applies, the emissions through each of those flues must be monitored separately.

Emission limit values for gas turbines using light and middle distillates as liquid fuels

20.

(1)

Gas turbines (including CCGT) using light and middle distillates as liquid fuels are subject to an emission limit value for NO_x of 90 mg/Nm³ and for CO of 100 mg/Nm³ unless the circumstances in sub-paragraph (2) apply.

(2)

Gas turbines for emergency use that operate less than 500 operating hours per year are not covered by the emission limit values set out in this paragraph.

Emission limit values for NO_x and CO for gas fired combustion plants

21.

(1)

The emission limit values (mg/Nm³) for NO_x and CO for gas fired combustion plants, unless the circumstances in sub-paragraphs (2) to (4) apply are as set out in Table 4—

Table 4

	NOx	CO
(1) Natural gas is naturally occurring methane with not more than 20% (by volume) of inerts and other constituents.
(2) 75 mg/Nm3 in the following cases, where the efficiency of the gas turbine is determined at ISO baseload conditions:
(i) gas turbines, used in combined heat and power systems having an overall efficiency greater than 75%,
(ii) gas turbines used in combined cycle plants having an annual average overall electrical efficiency greater than 55%,
(iii) gas turbines for mechanical drives.
(3) For single cycle gas turbines not falling into any of the categories mentioned under note (2) but having an efficiency greater than 35% – determined at ISO base load conditions – the emission limit value for NOx is 50xη/35 where η is the gas turbine efficiency at ISO base load conditions expressed as a percentage.
(4) 300 mg/Nm3 for such combustion plants with a total rated thermal input not exceeding 500 MW which were granted a permit before 27 November 2002 or the operators of which had submitted a complete application for a permit before that date, provided that the plant was put into operation no later than 27 November 2003.
Combustion plants firing natural gas with the exception of gas turbines and gas engines	100	100
Combustion plants firing blast furnace gas, coke oven gas or low calorific gases from gasification of refinery residues, with the exception of gas turbines and gas engines	200f5	_
Combustion plants firing other gases, with the exception of gas turbines and gas engines	200	_
Gas turbines (including CCGT), using natural gasf6 as fuel	50f7f8	100
Gas turbines (including CCGT), using other gases as fuel	120	_
Gas engines	100	100

(2)

For gas turbines (including CCGT), the NO_x and CO emission limit values set out in the table contained in this paragraph apply only above 70% load.

(3)

For gas turbines (including CCGT) which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003, and which do not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, the emission limit value for NOx is 150 mg/Nm³ when firing natural gas and 200 mg/Nm³ when firing other gases or liquid fuels.

(4)

A part of a combustion plant discharging its waste gases through one or more separate flues within a common stack, and which does not operate more than 1,500 operating hours per year as a rolling average over a period of 5 years, may be subject to the emission limit values set out in sub-paragraphs (2) and (3) in relation to the total rated thermal input of the entire combustion plant.

(5)

Where sub-paragraph (4) applies, the emissions through each of those flues must be monitored separately.

(6)

Gas turbines and gas engines for emergency use that operate less than 500 operating hours per year are not covered by the emission limit values set out in this paragraph.

Emission limit values for dust for combustion plants using solid or liquid fuels (except gas turbines and gas engines)

22.

Emission limit values (mg/Nm³) for dust for combustion plants using solid or liquid fuels with the exception of gas turbines and gas engines are as set out in Table 5—

Table 5

Total rated thermal input (MW)	Coal and lignite and other solid fuels	Biomass and peat	Liquid fuelsf9
(1) The emission limit value is 50 mg/Nm3 for the firing of distillation and conversion residues from the refining of crude oil for own consumption in combustion plants which were granted a permit before 27 November 2002 or where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003.
50-100	30	30	30
100-300	25	20	25
>300	20	20	20

Emission limit values for dust for combustion plants using gaseous fuels (except gas turbines and gas engines)

23.

Emission limit values (mg/Nm³) for dust for combustion plants using gaseous fuels with the exception of gas turbines and gas engines are as set out in Table 6—

Table 6

In general	5
Blast furnace gas	10
Gases produced by the steel industry which can be used elsewhere	30

CHAPTER 2

Emission limit values for combustion plants referred to in paragraphs 7(2) and 7(3)

Calculation of emission limit values

24.

(1)

All emission limit values are to be calculated—

(a)

at a temperature of 273.15K,

(b)

a pressure of 101.3kPa,

(c)

after correction for the water vapour content of the waste gases,

(d)

at a standardised O₂ content of—

(i)

6% for solid fuels,

(ii)

3% for combustion plants other than gas turbines and gas engines using liquid and gaseous fuels,

(iii)

15% for gas turbines and gas engines.

(2)

In case of combined cycle gas turbines with supplementary firing, the standardised O₂ content may be defined by SEPA, taking into account the specific characteristics of the installation concerned.

Emission limit values for SO₂ combustion plants using solid or liquid fuels (except gas turbines and gas engines)

25.

Emission limit values (mg/Nm³) for SO₂ for combustion plants using solid or liquid fuels with the exception of gas turbines and gas engines are as set out in Table 7—

Table 7

Total rated thermal input (MW)	Coal and lignite and other solid fuels	Biomass	Peat	Liquid fuels
50-100	400	200	300	350
100-300	200	200	300 250 in case of fluidised bed combustion	200
>300	150 200 in case of circulating or pressurised fluidised bed combustion	150	150 200 in case of fluidised bed combustion	150

Emission limit values for SO₂ combustion plants using gaseous fuels (except gas turbines and gas engines)

26.

Emission limit values (mg/Nm³) for SO₂ for combustion plants using gaseous fuels with the exception of gas turbines and gas engines are as set out in Table 8—

Table 8

In general	35
Liquified gas	5
Low calorific gases from coke oven	400
Low calorific gases from blast furnace	200

Emission limit values for NO_x for combustion plants using solid or liquid fuels (except gas turbines and gas engines)

27.

Emission limit values (mg/Nm³) for NO_x for combustion plants using solid or liquid fuels with the exception of gas turbines and gas engines are as set out in Table 9—

Table 9

Total rated thermal input (MW)	Coal and lignite and other solid fuels	Biomass and peat	Liquid fuels
50-100	300 400 in case of pulverised lignite combustion	250	300
100-300	200	200	150
>300	150 200 in case of pulverised lignite combustion	150	100

Emission limit values for NO_x and CO for gas turbines (including CCGT) using middle and light distillates as liquid fuels

28.

(1)

Gas turbines (including CCGT) using light and middle distillates as liquid fuels are subject to an emission limit value for NO_x of 50 mg/Nm³ and for CO of 100 mg/Nm³.

(2)

Gas turbines for emergency use that operate less than 500 operating hours per year are not covered by the emission limit values set out in this paragraph.

29.

(1)

Emission limit values (mg/Nm³) for NO_x and CO for gas fired combustion plants are as set out in Table 10—

Table 10

	NOx	CO
(1) For single cycle gas turbines having an efficiency greater than 35% – determined at ISO base load conditions – the emission limit value for NOx is 50xη/35 where η is the gas turbine efficiency at ISO base load conditions expressed as a percentage.
Combustion plants other than gas turbines and gas engines	100	100
Gas turbines (including CCGT)	50f10	100
Gas engines	75	100

(2)

For gas turbines (including CCGT), the NOx and CO emission limit values set out in this point apply only above 70% load.

(3)

Gas turbines and gas engines for emergency use that operate less than 500 operating hours per year are not covered by the emission limit values set out in this paragraph.

Emission limit values for dust for combustion plants using solid or liquid fuels (except gas turbines and gas engines)

30.

Emission limit values (mg/Nm³) for dust for combustion plants using solid or liquid fuels with the exception of gas turbines and gas engines are as set out in Table 11—

Table 11

Total rated thermal input (MW)
50-300	20
>300	10 20 for biomass and peat

Emission limit values for dust for combustion plants using gaseous fuels (except gas turbines and gas engines)

31.

Emission limit values (mg/Nm³) for dust for combustion plants using gaseous fuels with the exception of gas turbines and gas engines are as set out in Table 12—

Table 12

In general	5
Blast furnace gas	10
Gases produced by the steel industry which can be used elsewhere	30

CHAPTER 3

Emission monitoring

Measurements

32.

(1)

The concentrations of SO₂, NO_x and dust in waste gases from each combustion plant with a total rated thermal input of 100 MW or more must be measured continuously unless sub-paragraph (3) applies.

(2)

The concentration of CO in waste gases from each combustion plant firing gaseous fuels with a total rated thermal input of 100 MW or more must be measured continuously unless sub-paragraph (3) applies.

(3)

SEPA may elect not to require the continuous measurements required by sub-paragraphs (1) and (2) in the following cases—

(a)

for combustion plants with a life span of less than 10,000 operational hours,

(b)

for SO₂ and dust from combustion plants firing natural gas,

(c)

for SO₂ from combustion plants firing oil with known sulphur content in cases where there is no waste gas desulphurisation equipment,

(d)

for SO₂ from combustion plants firing biomass if the operator can prove that the SO₂ emissions can under no circumstances be higher than the prescribed emission limit values,

(4)

where SEPA does not require continuous measurements, measurements of dust and, for gas fired plants, CO are required at least once every 6 months,

(5)

where SEPA does not require continuous measurements, measurements of SO₂ andNOx are—

(a)

required at least once every 6 months, unless head (b) applies,

(b)

this sub-paragraph applies where SEPA has verified and approved of other procedures to determine SO₂ and NO_x emissions,

(c)

where SEPA has verified and approved of other procedures, procedures must—

(i)

use relevant CEN standards or British standards,

(ii)

when relevant CEN or British standards are not available, ISO or other international standards which ensure the provision of data of an equivalent scientific quality.

(6)

For combustion plants firing coal or lignite, the emissions of total mercury must be measured at least once per year.

Changes in fuel used or mode of operation of the plant

33.

(1)

SEPA must be informed of significant changes in the type of fuel used or in the mode of operation of the plant.

(2)

Where informed of a significant change in accordance with sub-paragraph (1), SEPA must decide whether the monitoring requirements in paragraph 32(1) to (4) and (6) of this schedule are still adequate or require to be adjusted.

Measurement of oxygen content, temperature, pressure and water vapour content of waste gases

34.

(1)

Continuous measurements carried out in accordance with paragraph 32(1) and (2) of this schedule must include the measurement of the oxygen content, temperature, pressure and water vapour content of the waste gases unless sub-paragraph (2) applies.

(2)

The continuous measurement of the water vapour content of the waste gases is not necessary where the sampled waste gas is dried before the emissions are analysed.

Relevant standards

35.

(1)

The following procedures must be carried out in accordance with relevant CEN or British standards, or where those are not available, ISO or other international standards which ensure the provision of data of an equivalent scientific quality—

(a)

sampling and analysis of relevant polluting substances,

(b)

measurements of process parameters,

(c)

quality assurance of automated measuring systems and the reference measurement methods to calibrate those systems.

(2)

Automated measuring systems must also be subject to control by means of parallel measurements with the reference methods at least once per year.

Confident interval values

36.

At the emission limit value level, the values of the 95% confidence intervals of a single measured result must not exceed the following percentages of the emission limit values—

(a)

carbon monoxide 10%,

(b)

sulphur dioxide 20%,

(c)

nitrogen oxides 20%,

(d)

dust 30%.

Validated hourly and daily averages

37.

(1)

The validated hourly and daily average values are to be determined from the measured valid hourly average values after having subtracted the value of the confidence interval specified in paragraph 36 of this schedule.

(2)

Any day in which more than three hourly average values are invalid due to malfunction or maintenance of the automated measuring system must be invalidated.

Sulphur content

38.

Where plants are required to comply with the rates of desulphurisation in paragraph 9 of this schedule, the sulphur content of the fuel which is fired in the combustion plant must also be regularly monitored.

CHAPTER 4

Assessment of compliance with emission limit values

39.

(1)

For continuous measurements, the emission limit values set out in Chapters 1 and 2 of this schedule are to be regarded as having been complied with if the evaluation of the measurement results indicates, for operating hours within a calendar year, that all of the following conditions have been met—

(a)

no validated monthly average value exceeds the relevant emission limit values set out in Chapters 1 and 2 of this schedule,

(b)

no validated daily average value exceeds 110% of the relevant emission limit values set out in Chapters 1 and 2 of this schedule,

(c)

in cases of combustion plants composed only of boilers using coal with a total rated thermal input below 50 MW, no validated daily average value exceeds 150% of the relevant emission limit values set out in Chapters 1 and 2 of this schedule,

(d)

95% of all the validated hourly average values over the year do not exceed 200% of the relevant emission limit values set out in Chapters 1 and 2 of this schedule,

(e)

validated average values are determined as set out in paragraph 37 of this schedule,

(f)

for the purpose of the calculation of the average emission values, the values measured during the periods referred to in paragraphs 8 and 11 of this schedule as well as during the start-up and shut-down periods are to be disregarded.

(2)

Where continuous measurements are not required, the emission limit values set out in Chapters 1 and 2 of this schedule are to be regarded as having been complied with if the results of each of the series of measurements or of the other procedures defined and determined according to the rules laid down by SEPA do not exceed the emission limit values.

CHAPTER 5

Minimum rate of desulphurisation

40.

Minimum rate of desulphurisation for combustion plants referred to in paragraphs 6(1) and (2) of this schedule is as stated in Table 13—

Table 13

	Minimum rate of desulphurisation
(1) For combustion plants firing oil shale, the minimum rate of desulphurisation is 95%
Total rated thermal input (MW)	Plants which were granted a permit before 27 November 2002 or those where a complete application for a permit was submitted before that date, provided that the plant was put into operation no later than 27 November 2003	Other plants
50-100	80%	92%
100-300	90%	92%
>300	96% f11	96%

41.

The minimum rate of desulphurisation for combustion plants referred to in paragraph 6(3) of this schedule are as set out in Table 14—

Table 14

Total rated thermal input (MW)	Minimum rate of desulphurisation
50—100	93%
100-300	93%
>300	97%

42.

The minimum rates of desulphurisation set out in this Chapter apply as a monthly average limit value.

CHAPTER 6

Average emission limit values for multi-fuel combustion plants within a refinery

43.

(1)

Average emission limit values (mg/Nm³) for SO₂ for multi-fuel firing combustion plants within a refinery, with the exception of gas turbines and gas engines, which use the distillation and conversion residues from the refining of crude-oil for own consumption, alone or with other fuels—

(a)

for combustion plants which were granted a permit before 27 November 2002 or the operators of which had submitted a complete application for a permit before that date, provided that the plant was put into operation no later than 27 November 2003 is 1000 mg/Nm³,

(b)

for other combustion plants: 600 mg/Nm³.

(2)

These emission limit values are to be calculated at—

(a)

a temperature of 273.15K,

(b)

a pressure of 101.3kPa,

(c)

after correction for the water vapour content of the waste gases and

(d)

at a standardised O₂ content of—

(i)

6% for solid fuels,

(ii)

3% for liquid and gaseous fuels.”