Environmental Permit Application Supplementary information€¦ · 4 1.2 Description of the installation . 1.2.1 Overview & process flow . Saws cut kiln dried timber to the required

Environmental Permit Application

Supplementary information

LAPPC Part B Permit Application

Nuneaton Roof Truss Limited

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Table of Contents

1.0 The installation & activities undertaken 3 1.1 Introduction 3 1.2 Description of the installation 4 1.2.1 Overview & process flow 4 1.2.2 Technical description: Wood products manufacturing 4 1.2.3 Technical description: Waste wood combustion 5

2.0 Emissions 8

2.1 Foreseeable emissions 8 2.2 Emissions quantification 8

3.0 Controlling emissions 9

3.1 Biokompakt ECO 150 9 3.2 Dragon D240 10

4.0 Unintentional releases 11 5.0 Monitoring emissions 12

5.1 Wood products manufacturing 12 5.2 Waste wood combustion 12

6.0 Environmental management techniques 13

6.1 Training 13 6.2 Environmental logbook 13 6.3 LEV testing 13 6.4 Boiler maintenance 13

7.0 Impact on the environment 14

Appendices

Appendix 1 - Product data sheets Appendix 2 - Air Quality Assessment Appendix 3 - Biokompakt ECO 150 RHI Certificate Appendix 4 - Dragon D240 RHI Certificate Appendix 5 - Environmental Logbook Appendix 6 - Sensitive local environments map



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1.0 The installation & activities undertaken

1.1 Introduction

Nuneaton Roof Truss Limited (the Operator) is a specialist manufacturer of roof trusses, rafters, attic trusses, floor joists and spandrel panels for the building industry.

Figure 1: Roof truss components

Kiln dried softwood is cut to the desired angle, drilled and milled to the required specification for the product produced.

Trusses and joists are constructed using metal plates and webs: industrial presses mate metal parts with the cut timber parts in the manufacture of trusses and joists. Spandrel Panels are structural timber panels clad with OSB board and plasterboard or ply, to form the gable end or party wall of a property, replacing the need for conventional masonry construction

The manufacturing installation in Nuneaton contains the following Part B regulated activities

Waste wood incineration >50kg/hr.

Manufacturing products wholly or mainly of wood >10,000m3 in any 12-month period*. * Current throughput is actually 8912.70m3 (based on 2018 data), which is below

threshold, however the Operator seeks to include both activities in the permit applied for as a ‘combined activity’ for the purposes of fees and charges, and for ‘future- proofing’ the Part B permit.

The following guidance has been used in the preparation of this application in order to ensure that the Operator applies Best Available Techniques to the operation of the regulated activities:

PG1/12(12) - Combustion of waste wood (2018 draft).

PG6/02(12) - Manufacture of timber and wood-based products



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1.2 Description of the installation

1.2.1 Overview & process flow

Saws cut kiln dried timber to the required length and angle, and milling machines cut notches and other features into the wood to assist joist and truss construction. Board materials such as oriented strand board (OSB) and plywood are also used in the manufacture of Spandrel panels.

Wood offcuts and wood dust produced in the manufacturing process will be burnt for the purposes of space heating in three proposed biomass boilers due to be installed on site in Q4 2019.

Finished products are stacked for shipping to the customer.

The general process flow is shown below:

Figure 2: Process flow with contained and fugitive emissions 1.2.2 Technical description: Wood products manufacturing

Wood products manufacturing currently operates at 8912.70m3 (based on 2018 throughput). All extraction equipment is housed within the process building meaning that timber machining activities other than sawing will be deemed ‘excluded activities’ because they are unlikely to result in the release of any substance in Part 1 of Schedule 1 (particulate matter) in a quantity capable of causing significant harm. The Operator seeks to include timber products manufacturing within the Part B permit in any event as a matter of good operational practice.

The equipment in use in the activity is as follows, along with the relevant abatement plant:

Equipment Abatement Robinson EOT Roof Truss Saw Air Plants twin sock filter De Pauw Quadricut saw Offcut conveyor Hundegger Turbo Drive Saw, drill and mill Dustraction filter system and offcut conveyor Stavelse metaalbouw PCI 30 truss press N/A Robinson EOT Roof Truss Saw Air Plants single sock filter AV Birch Uni Roll beam roller N/A AV Birch Splicer Press N/A

Table 1: Wood machining equipment



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All dust abatement plant is located internally and vents internally, meaning no contained or fugitive emissions to the external environment. Dust collection bags are transparent in order to facilitate replacement when full.

Figure 3: Internal dust collection systems

Collected wood dust and sawn wooden block offcuts are currently stored on-site prior to off-site disposal. The operator proposes to use the collected clean waste wood dust and offcuts in the proposed biomass appliances described in section 1.2.3 of this application for the purposes of space heating in the factory building. 1.2.3 Technical description: Waste wood combustion

Un-treated clean waste wood from the manufacturing process is proposed for combustion in one of three (3) boilers planned for installation in Q4 of 2019 for the purpose of space heating.

The proposed fuels are as follows:

Kiln dried structural softwood timber Oriented strand board, for example Kronospan OSB3. Plywood, for example RIGA Ply. Unpainted pallet wood (HT heat treated pallet wood only).

The board materials do not contain halogenated organic compounds or heavy metals from wood-preservative treatment or coating. The manufacturer’s material safety data sheets confirming this are included as Appendix 1.

Incineration and co-incineration plants that burn clean wood waste are excluded from chapter 4 of the industrial Emissions Directive meaning that the plant referred to in this application can collectively fall under the Part B swip definition. The equipment is not subject to the full requirements of the Waste Incineration Directive (WID), nor should any of it be considered Schedule 13 SWIP (WID small waste incineration plant).



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The Operator proposes to use the following waste wood burning appliances:

Appliance Output kW

Maximum consumption

Kg/Hr Fuelling

Dragon D240 240 49 Manual

Biokompakt ECO 150 135 28 Automatic

Biokompakt ECO 150 135 28 Automatic

Table 2: Wood combustion equipment Biokompakt ECO 150:

Wood dust and small offcuts of wood / ply / OSB / pallet are destined for combustion in either of the two Biokompakt appliances. The Operator proposes to install an Untha LRK shredder (or similar) for the size reduction of small offcuts of wood, broken pallets and board materials that are surplus to requirements in truss construction. A feed conveyor will transport the chipped materials into a containerised fuel store. The fuel store houses two rotary agitators and feed augers to the Biokompakt appliances. The augers automatically feed the appliances combustion chambers according to heat demand.

Figure 4: Proposed Biokompakt biomass appliances

1. Boiler. 2. Boiler control. 3. Chimney connection. 4. Stoker with back burn protection. 5. Fuel extraction screw.

6. Fuel from store. 7. Fuel store door. 8. Ash mechanism 9. Chimney

Under the influence of primary and secondary air the fuel is burnt inside the combustion chamber. The process is controlled from a central boiler control. The plant is controlled fully automatically in the power range between 30 and 100%. The control also includes the control of all safety-related equipment including a stoker sprinkler system and burn back protection device.

Excess wood chip will be transferred by auger into a stand trailer proposed for the yard area.



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Dragon D240:

Solid block kiln dried timber offcuts are planned as fuel for the Dragon D240, these being the larger pieces of truss wood that would consume significant energy to chip down to a size suitable for the automatic fuel feed systems of the Biokompakt appliances. This is a hand fed appliance.

Figure 5: Proposed Dragon D240 & controller Being a hand fed appliance, the Dragon D240 does not need the burn back protection devices required by auger fuelled systems, however it is equipped with a controller system, which is pre-set with settings for:

Stack Temperature. Water Temperature. Water Temperature required before pump starts. Flue Temperature when re-fuel is required. Flue Temperature when fan stops, if boiler is left to burn out. Pump Speed to be reached before the bypass pump stops.

The relevant settings will be determined by the installed at the time the plant is commissioned on site according to the required heat demand of the installation. All appliances will be equipped with their own dedicated 12m stainless steel chimney stacks (one per appliance) for the effective dispersion and dilution of emissions. Stack height has been determined in the air quality assessment in Appendix 2. The layout of the proposed installation is shown in the plan ‘Biomass Plant Area Plan Layout’.



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2.0 Emissions

2.1 Foreseeable emissions

Foreseeable emissions to air from the proposed activities are identified and characterised as contained (point source) or fugitive emissions as follows:

1. Contained emissions from waste wood combustion. 2.2 Emissions quantification

Emissions information has been included in the air quality assessment in Appendix 2, and is reproduced as follows:

Emission

Biokompakt 135 kWth Biomass Boiler

Dragon D240 kWth Biomass Boiler

Discharge rate (g s-1)

Discharge rate (g s-1)

Oxides of Nitrogen (NOx) 0.016 0.007

Nitrogen Dioxide (NO2)* 0.008 0.0035

Particulates (PM10)** 0.001 0.01

Carbon Monoxide (CO) 0.0001 -

Notes: * Assumes 50% conversion of NOX to NO2 in the short-term.

** Assumes that all of the particulate emissions are as PM10 By way of comparison, Clean Air Act Exempt emission rates for smoke (grit and dust AKA particulate matter) for appliances rated between 44kW and 240kW output are calculated as follows:

(Output(kW) x 2.42) – 86.9 = Emission limit (g/h)

For the Biokompakt 135, this amounts to a limit of 239.8g/h

For the Dragon D240, this amounts to a limit of 493.9g/h The data supplied in the air quality assessment in Appendix X indicates that both appliances would be well within the calculated maxima at 3.6g/h and 36g/hr respectively, and assuming that all of the grit and dust emissions are as PM10. In addition, both appliances have Renewable Heat Incentive (RHI) certification (Appendix 3 for the Biokompakt and Appendix 4 for the Dragon).



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3.0 Controlling emissions

The proposed technologies and other techniques to prevent, or where that is not practicable, to reduce emissions to air are as follows: 3.1 Biokompakt ECO 150

Good combustion will be maintained in order to minimise all emissions to air. The wood chip fuel will be stored in an enclosed fuel store and therefore be protected from the elements and kept dry for good efficient combustion. Prohibited materials will not be burnt.

The appliance is equipped with an automatic hot air ignition system, which heats fuel in the combustion chamber to achieve glowing embers. The integrated MC-Processor monitors flue gas temperature and automatically feeds in fuel for the fire as the temperature increases. If automatic ignition is not successful (if the set temperature in the flue indicating combustion is not achieved), the appliance shuts down and a fault is displayed on the display screen.

Once combustion flue gas temperature is achieved, combustion starts, and a lambda probe detects the oxygen content in the combustion gases. The MC-Processor will adjust combustion air and fuel feed for optimum combustion.

Figure 6: Boikompakt ECO 150 The Biokompakt ECO 150 is also equipped with an on-board electrostatic filter to minimise fine particulate emissions that can be present with chipped and dust fuels. The filter is automatically cleaned as part of normal operation.

Ash is removed from the retort via an ash auger. All ash will be stored in a covered container/bin prior to off-site disposal.



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As with all combustion appliances, emissions during shut-down are less easy to control as the fire burns out and the appliance cools, and reliance will be placed on the chimney stack to effectively disperse emissions.

Training will be provided by the supplier of the appliance in order to ensure that the Operator is fully aware of how the appliance should be operated and maintained. 3.2 Dragon D240

Good combustion will be maintained in order to minimise all emissions to air. Emissions during start-up will be minimised as far as practicable, by using a clean dry kindling, and not over-loading the appliance as soon as the fire is lit. Accelerants such as diesel will not be used for ignition.

The Dragon D240 will be burning larger blocks of essentially virgin wood, which means that the appliance should be able to maintain a fairy high combustion temperature as the blocks combust and have good air flow around them (compared to chips that form a smaller combustion surface, and board material that have no air gaps at all).

Once the fire is lit and the door closed, the combustion fan will gradually speed up to feed the fire. As the flue temperature approaches the set temperature the fan will slow down & then regulate it speed automatically to maintain the required flue temperature. As the water in the boiler heats up, the water pump will start automatically and adjust its speed to maintain the required water temperature. The controller uses the settings to modulate the water pump and combustion fan within the set tolerances. A warning lamp or buzzer can also be connected to indicate when re-fuelling is required in order to prevent significant cooling of the combustion chamber itself, and to promote good combustion of a new fuel load. The fuelling strategy will be determined by the required heat demand of the installation, and will be communicated to the Operator by the installer on the commissioning of the appliance.

Figure 7: Dragon D240 control settings If fuel is not added the system will sequentially shut down the water pump and combustion fan as the temperature drops. As with all combustion appliances, emissions during shut-down are less easy to control as the fire burns out and the appliance cools, and reliance will be placed on the chimney stack to effectively disperse emissions.

Ash will be removed from the retort manually as required. All ash will be stored in a covered container/bin prior to off-site disposal.



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4.0 Unintentional releases

The likely unintentional releases from the proposed activity are as follows:

Localised smoke or odour from poor combustion in the event of power failure or other breakdown (all).

Localised smoke or odour from over fuelling (Dragon). Increased particulate from failure of electrostatic filter (Biokompakt).

Unintentional releases from the installation have also been subjectively considered, both in terms of the nature of these accidental releases, the worst case environmental hazard and the subsequent environmental risk using the following risk matrix: Severity of impact

Low 1

Medium 2

High 3

Likelihood of occurrence

Infrequent 1

Trivial 1

Acceptable 2

Moderate 3

Regular 2

Acceptable 2

Moderate 4

High Risk 6

Frequently 3

Moderate 3

High Risk 6

Unacceptable risk 9

Foreseeable accidental release affecting off-site receptors

Likelihood of occurrence Severity of impact Risk score

Localised smoke or odour from poor combustion in the event of power failure or other breakdown.

Infrequent Power supply

interruptions are uncommon.

Third-party service and management of appliances.

Medium Potential for off-site impact. Short duration until fuel in

combustion chamber is exhausted.

2 Acceptable

Localised smoke or odour from over fuelling (Dragon).

Infrequent Procedures in place

and staff will be trained in the correct use of the plant.

Third-party service and management of appliances.

Medium Potential for off-site impact. Short duration until fuel in

combustion chamber is exhausted. 2

Acceptable

Increased particulate from failure of electrostatic filter (Biokompakt).

Infrequent Power supply

interruptions are uncommon.

No moving parts. Third-party service

and management of appliances.

Low Unlikely to have off-site impact. Short duration until fuel in

combustion chamber is exhausted.

1 Trivial

The combination of good plant operation, management and maintenance and fuelling practices coupled with daily emissions monitoring will ensure that the risk of the environmental hazards from actually occurring through truly unforeseen or uncontrolled emissions remain as low as possible.



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5.0 Monitoring emissions

The emissions monitoring proposed is described as follows: 5.1 Wood products manufacturing

All wood products manufacturing equipment is housed indoors, therefore the likelihood of fugitive emissions of any kind is minimal to nil; however the Operator proposes to implement the following daily assessments:

Visual assessments of ductwork & collection bags for leaks and spills. Housekeeping.

The assessments detailed above will form part of the environmental procedures operated on site, and will be finalised on receipt of permitting requirements. 5.2 Waste wood combustion

Numerical stack emission limits will not apply to any of the appliances because no individual appliance in its own right has a burn rate of 90kg/hr or more (equivalent to 400kW). The Operator does however propose to implement the following daily assessments:

Visual and olfactory assessments for smoke and odour from the heater chimney stacks. Housekeeping

The assessments detailed above will form part of the environmental procedures operated on site, and will be finalised on receipt of permitting requirements.



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6.0 Environmental management techniques

The Operator proposes to use a combination of site management and plant maintenance techniques to deliver compliance with environmental permitting requirements, including:

Training. Environmental logbook. LEV testing. Boiler maintenance

6.1 Training

Training will be provided by the supplier of the appliances in order to ensure that the Operator is fully aware of how each appliance should be operated, including ensuring that the appliance is not overloaded and not used for the combustion of any prohibited materials. The appliance operating instructions will also be retained on site for reference. 6.2 Environmental logbook

An environmental logbook will be maintained on site, incorporating daily visual checks on emissions from the biomass appliances, and internal and external housekeeping. The draft documents proposed are detailed in Appendix 5, and will be revised in light of any additional requirements required by any permit granted. 6.3 LEV testing

12-14 month LEV testing will be undertaken on extract equipment and filter systems in order to ensure that they are working correctly and as a third-party assessment of system performance. 6.4 Boiler maintenance

AMP Energy Services Limited will be responsible for the service and operation of the boiler with limited involvement on site, namely emptying ash bins.



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7.0 Impact on the environment

The potential significant local environmental effects (including nuisance) of the foreseeable emissions have been minimised as described in this application, taking account of applicable Best Available Techniques proposed by this application.

Dusty emissions will be minimised as far as practicable, and are unlikely to extend outside the process building.

Chimney heights should also be sufficient to ensure that emissions including smoke and odour do not cause a nuisance to neighbours, nor cause any significant impact beyond the installation boundary. Indeed, the air quality assessment in Appendix 2 considers impacts to be negligible in relation to the EPUK/IAQM impact descriptors.

No SSSIs or European protected sites are within 2km of the activity. A map of local SSSIs or European protected sites is in Appendix 6 by way of confirmation.



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Appendices

Appendix 1 - Product data sheets Appendix 2 - Air Quality Assessment Appendix 3 - Biokompakt ECO 150 RHI Certificate Appendix 4 - Dragon D240 RHI Certificate Appendix 5 - Environmental Logbook Appendix 6 - Sensitive local environments map

Appendix 1: Product data sheets

Appendix 2: Air Quality Assessment

Appendix 3: Biokompakt ECO 150 RHI Certificate

Appendix 4: Dragon D240 RHI Certificate

Appendix 5: Environmental Logbook

Appendix 6: Sensitive local environments map

Documents

Environmental Permit Application Supplementary information€¦ · 4 1.2 Description of the installation . 1.2.1 Overview & process flow . Saws cut kiln dried timber to the required