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VdS Guidelines for Fire Protection VdS 2371en

Flue Gas Desulphurisation Plants (FGD)

VdS 2371en : 1993-10 (01)

Publisher and publishing house: VdS Schadenverhütung GmbH

Amsterdamer Str. 174 50735 Köln, Germany Phone: +49 221 77 66 0; Fax: +49 221 77 66 341

Copyright by VdS Schadenverhütung GmbH. All rights reserved.

VdS 2371en : 1993-10 (01) Flue Gas Desulphurisation Plants (FGD)

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VdS Guidelines for Fire Protection

Flue Gas Desulphurisation Plants (FGD)

CONTENTS 1 General................................................................................................................ 3 2 Terms .................................................................................................................. 6 3 Scope of validity and application..................................................................... 7 3.1 Basic fire protection measures (Part A)............................................................... 7 3.2 Additional fire protection measures during installation and for maintenance

and repair work (Part B)........................................................................................ 8 Part A Basic fire protection measures ........................................................................ 8 4 Structural fire protection measures................................................................. 8 4.1 Building design..................................................................................................... 8 4.2 Separation of the flue gas desulphurisation plant from other plant sections....... 8 4.3 Sub-division of flue gas desulphurisation plants into fire protection compartments .... 8 4.4 Smoke and heat exhaust ventilation systems ..................................................... 9 5 Measures for fire detection and alarm............................................................. 9 6 Fire fighting measures ...................................................................................... 9 6.1 Fire extinguishers, wall hydrants, risers .............................................................. 9 6.2 Fire brigade and operation conditions ............................................................... 10 6.3 Automatic fire extinguishing systems ................................................................ 10 6.4 Other fire extinguishing equipment.................................................................... 10 6.5 Extinguishing water supply ................................................................................ 11 6.6 Extinguishing water retention systems .............................................................. 11 7 Organisational fire protection measures ...................................................... 11 8 Lightning protection measures...................................................................... 11 Part B Additional fire protection measures during installation and for

maintenance and repair work......................................................................... 11 9 Separation measures ...................................................................................... 11 10 Measures for fire detection and alarm........................................................... 12 11 Fire fighting measures .................................................................................... 13 11.1 Manual fire fighting ............................................................................................ 13 11.2 Possible uses of plant technology ..................................................................... 13 12 Organisational fire protection measures ...................................................... 14 12.1 Setting up and operation of construction site /14/ ............................................. 14 12.2 General organisational fire protection measures............................................... 15

Flue Gas Desulphurisation Plants (FGD) VdS 2371en : 1993-10 (01)

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12.3 Special organisational fire protection measures for rubber lining and coating work…………………. ............................................... ……………………16

12.4 Complementary measures................................................................................. 19 13 Literature .......................................................................................................... 20


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1 General Flue gas desulphurisation plants are used for fuel-burning systems in power plants and waste incineration plants. The wet or spray absorption process has gained great accep-tance for flue gas desulphurisation plants (see figure 1). The fire hazard shall be evalu-ated individually, depending on the process applied.

Figure 1: Principle of a flue gas desulphurisation plant

According to the experience gathered so far, the hazard of an outbreak of fire is particu-larly high in the construction phase and during inspection work. The recommendations given in these guidelines are based on the knowledge available today. They contain measures that reduce the fire hazard and its possible consequences.

A fire in a flue gas desulphurisation plant finds all the prerequisites for causing large-scale damage. Fire spread often cannot be controlled in these large structures filled with equipment items; smoke development is intense.


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The hazard potential during construction and inspections is characterised:

a) by a high process- and plant-specific fire load, e.g.

absorber with internal rubber lining,

absorber made of glass-fibre reinforced plastic materials (GRP),

clean gas ducts with internal lining and GRP liners,

plastic internals in the flue gas desulphurisation plant and in the cooling tower,

expansion joints and pipework lined with rubber or made of rubber materials,

fillings made of polyethylene (PE) and polypropylene (PP);

b) by an increased fire load during installation and maintenance and repair work carried out at a later date, caused by additional material, e.g.

flammable scaffolding,

covering films,

packaging materials,

glues and laminates containing solvents,

storage of flammable materials, especially of flammable liquids;

c) by ignition sources such as

welding, torch cutting and other hot works,

heaters such as radiant heaters,

lighting systems,

electric systems,

smoking.

2 Terms Absorber: Reaction vessel for absorbing the SO2 from the combustion flue gases.

Clean gas: Flue gas free of SO2.

Raw gas : Combustion flue gas from the boiler plant.

Expansion joint: Connecting element for installation and for compensating expansions of lines subject to a temperature load.

Fillings: Elements required for enlarging the reaction surface.

GRP liner: Clean gas duct made of glass-fibre reinforced laminate (normally used in the cooling tower inlet section).

External lightning protection: Measures suited for protecting a building against the ef-fects of a lightning stroke.


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Internal lightning protection: Measures suited for protecting electric systems against the effects of the lightning stroke current and the magnetic and electric fields created by it.

Overvoltage protection: Measures that reduce any occurring overvoltages to a level that is safe for electric equipment.

Stationary extinguishing devices: Stationary fire-fighting equipment with stationary stock of extinguishing agent and automatic triggering.

Temporary extinguishing devices: Limited in time, stationary fire-fighting equipment piping network with mobile stock of extinguishing agent and manual triggering.

Feeding of extinguishing water is outside of the area protected by fire-fighting equipment from a safe extinguishing water supply by coordination with the local fire brigade.

Fire regulations: Setting-up of preventive measures

against the outbreak of a fire,

regarding the behaviour in case of a fire and

regarding the behaviour after a fire.

Site regulations: Binding rules of conduct for the trades working on a construction site.

Alarm plan: A plan set up for a specific object, aiming at quickly alarming fire-fighters and other authorities in case of a loss occurrence.

Fire brigade plan (fire protection plan): A plan for fire-fighters set up for a specific ob-ject. It indicates the major hazards and the safety equipment available for preventive fire protection and fire defence.

Safety zone: Area to be marked where particular safety precautions shall be taken.

Explosion protection zone: Area to be marked according to the explosion protection regulations (German abbr.: EX-RL) where particular explosion protection measures shall be taken.

3 Scope of validity and application These regulations apply to the construction and the operation of flue gas desulphurisation plants (FGD).

3.1 Basic fire protection measures (Part A) In case of existing plants that do not yet comply with these guidelines, the operational and organisational fire protection measures as well as fire defence should be completed within a reasonable period. Structural and special technical fire protection measures shall be carried out within the framework of existing possibilities. They are to reduce the fire hazard and prevent both rapid fire spread and unhindered smoke spread within the plant.


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3.2 Additional fire protection measures during installation and for maintenance and repair work (Part B)

In addition to the fire protection measures for flue gas desulphurisation plant operation – Part A – further measures are necessary during all construction and installation work and during all off-stream periods due to inspections, maintenance work etc.

In consideration of the existing installations, the technical design of the flue gas desul-phurisation plant and the experience gathered regarding damage, a suitable fire protec-tion concept /1/ shall be compiled from a number of individual measures (e.g. creation of fire compartments, fire detection and fire-fighting equipment) for the plant in question.

Part A Basic fire protection measures

4 Structural fire protection measures

4.1 Building design The fire protection design of the buildings is of major significance. As a fundamental rule, class A building materials according to DIN 4101 /2/ (non-combustible building materials) shall be used. This applies in particular to outside walls and roofs. Load-bearing elements shall be executed in accordance with fire resistance class F 90-A according to DIN 4102 (fire-resistant).

4.2 Separation of the flue gas desulphurisation plant from other plant sections

When plants are newly built, a spatial or structural separation between the power station and the flue gas desulphurisation plant shall be strived for. The necessary spatial separa-tion depends on the hazard potential and the plant height and should not be less than 20 m. In case of particular hazards, this minimum distance should be reasonably enlarged.

In case of subsequent installation of a flue gas desulphurisation plant in existing power plants and refuse incineration plants, a separation often is impossible. This usually results in a compact combined plant. In these cases, a structural separation between the flue gas de-sulphurisation plant and adjoining areas shall be provided by means of a fire break wall /3/.

When arranged and executed properly, structural separations are suitable alternatives to spatial separations.

4.3 Sub-division of flue gas desulphurisation plants into fire protection compartments

Sections that are essential to operations such as

electrical operations rooms,

control and switchgear rooms and rooms accommodating the process control system (PCS),

cable ducts, cable basements, cable shafts,


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shall be separated from adjoining sections in accordance with fire resistance class F 90-A according to DIN 4102.

The same applies to those operational sections that increase the hazard, e.g. storage ar-eas for combustible substances.

Fire resisting closures in structural separations shall comply with fire resistance class T 90 according to DIN 4102. These shall be equipped with hold-open devices approved by the building control authorities in order to avoid that such closures are kept open by wedges or by tying up.

Wall openings for cables, pipes etc. shall be protected with separations approved by the building control authorities.

Separating mechanisms in the course of the clean gas duct should be integrated into the planning as early as during the drafting phase of new flue gas desulphurisation plants. Louvre and swinging flaps such as those usually used for sub-dividing the raw gas duct are suitable for this purpose.

4.4 Smoke and heat exhaust ventilation systems Smoke and heat exhaust ventilation systems according to VdS guidelines /4/ shall be provided. Mechanical smoke exhausts can be installed for internal rooms, e.g. internal electric rooms.

5 Measures for fire detection and alarm The hazard situation requires early fire detection in order to be able to start efficient fire-fighting measures. For this reason, the entire flue gas desulphurisation plant should be monitored by an automatic fire detection and fire alarm system, including the electric rooms, control rooms, pump rooms, cable ducts, basements and shafts, process control systems etc.

The fire detection and fire alarm system shall be installed according to the relevant VdS guidelines /5/ and the VDE regulations /6/. The alarm signal shall be transmitted to a per-manently manned location from where the fire brigade is directly alerted.

6 Fire fighting measures

6.1 Fire extinguishers, wall hydrants, risers Fire extinguishers shall be fitted at spots that are well visible and easily accessible at all times. Their number depends on the operational and organisational fire protection meas-ures to be defined. When selecting suitable fire extinguishers, the “Safety regulations for equipping workplaces with fire extinguishers” /7/ shall be observed.

Wall hydrants connected with hoses and multipurpose jet pipes shall additionally be in-stalled in all buildings so that any point of the operations can be reached by an effective water jet. The wall hydrants shall be arranged so that they can be safely reached in case of a fire. To supply the wall hydrants, wet risers (at least DN 100) shall be installed in the staircases according to the building progress and be kept operational. A discharge pres-sure of at least 3 bar shall be available at the highest tapping point. The tapping points


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should be provided on every level of use directly next to the staircase door outside the staircase. Dimensionally stable hoses shall be used.

To have a sufficient amount of extinguishing agent available in all operational areas, cen-tral fire-fighting stations shall be set up at suitable and well accessible points, by coordi-nation with the fire brigade. These stations shall contain the required extinguishing agents and equipment (jet pipes, hoses, fire extinguishers, special extinguishing agents). This in particular applies to the construction and inspection phases as experience shows that these periods involve increased fire hazards.

6.2 Fire brigade and operation conditions Besides the existing public fire brigade, a permanently available plant fire brigade /8/ shall be set up as early as during the construction phase.

To ensure sufficient operation conditions, areas of movement and bypasses for fire brigade vehicles, accesses and lifts (fire lifts) shall be provided by agreement with the fire brigade.

6.3 Automatic fire extinguishing systems In flue gas desulphurisation plants, areas subject to a particularly high hazard and those presenting a high fire load shall be protected by a stationary VdS-approved fire extin-guishing system, e.g.

Sprinkler systems /9/,

Water spray systems /10/,

Foam extinguishing systems /11/,

Inert gas extinguishing systems /12/.

Sprinkler systems are particularly suited for storage rooms and workshops as well as emergency power supply systems, compressor rooms, possibly cable ducts, shafts and basements and for other rooms that are subject to a fire hazard and unmanned during operation.

Water spray systems make sense above all for cable ducts, shafts and basements, lu-bricant and oil storage areas, areas accommodating hydraulic oil systems and for oil-filled transformers.

Foam extinguishing systems shall be used especially in areas where flammable liquids are stored and may leak.

Inert gas extinguishing systems are used especially for local application for electric systems, e.g. switchgear cabinets, electronics cubicles, false floors and as a room pro-tection for emergency power supply systems, inverter groups etc.

6.4 Other fire extinguishing equipment Other fire extinguishing equipment such as permanently installed feed and distributor lines (temporary fire extinguishing devices), mobile fire extinguishing systems and special fire extinguishers (high expansion foam generators) may be required especially during in-spection work (see part B of these guidelines). The installation of mobile water spray ex-tinguishing equipment makes sense for inspections of plant components with an internal rubber lining.


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6.5 Extinguishing water supply An extinguishing water ring line system of at least DN 200 shall be installed on the prem-ises. A water supply of at least 5,000 l/min. shall be ensured for a two-hour period. Pillar hydrants shall be provided every 50 m.

If necessary, frost-protected water draw-off points such as cooling tower pits, ponds or other open water bodies can be considered in calculating the total water supply. Booster pumps shall be designed so that a discharge pressure of 3 bar is still guaranteed at the highest tapping point of the jet pipe.

6.6 Extinguishing water retention systems Measures shall be provided which prevent uncontrolled ingress of contaminated extin-guishing water into the public sewage network and/or into the ground or in watercourses.

The following extinguishing water retention options are available:

outside of buildings

extinguishing water retention basins into which the contaminated water is intro-duced through collecting channels or discharge pipes or blocking of channels and diverting the extinguishing water into collecting basins;

inside of buildings

building areas created by means of raised concrete/masonry edges and water-proof construction (e.g. basement rooms). A connection to the outside for pump-ing out the extinguishing water should exist.

7 Organisational fire protection measures In addition to structural and operational fire protection measures, organisational fire pro-tection is of major significance. The recommended measures are dealt with in detail in part B of these guidelines.

8 Lightning protection measures High buildings shall be equipped with a lightning protection system in connection with a foundation earth. Besides external lightning protection, internal lightning protection and overvoltage protection shall also be provided for safeguarding the process control sys-tems /13/.

Part B Additional fire protection measures during installation and for maintenance and repair work

9 Separation measures During maintenance and repair work, the flue gas desulphurisation plant shall be separated from other plant sections by separating the flue gas path. Fully adequate, stationary fire stop seals in the sense of a structural fire compartment division (inspected systems approved by the building control authorities) are usually difficult to retrofit into an operational plant


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because of their size and the design of the flue gas desulphurisation plant and also for proc-ess engineering reasons.

These measures may be dismounted only directly before putting the flue gas desulphuri-sation plant into operation again.

The following systems can be recommended as suitable elements for a room closure with a fire resistance character (firestop seal) (see figure 1):

fire-resistant design F 90-A, following DIN 4102, consisting of a steel framework faced with non-combustible panels whose weight can be supported by the plant components as an additional load;

steel panel, protected by an exposure protection system (density of discharge: 15mm/min, automatic triggering by detector pipework). Water drainage shall be en-sured.

The following locations are recommended for installing such components (see figure 1):

at the last expansion joint gap of the raw gas duct before entering the absorber unless a louvre or swinging flap has already been installed here for process engi-neering reasons (bypass);

at the first expansion joint gap of the clean gas duct downstream of the absorber;

at the expansion joint gap directly before the clean gas duct transits or enters the natural-draught cooling tower or chimney.

By means of further shut-off devices further plant parts can be separated from one an-other if necessary. These include among others:

filtering units;

gas pre-heaters; and

denitrification plants (DeNOx plants).

Other pipework such as:

suspension lines;

emergency drain lines etc.

can be efficiently shut off by removing piping parts or by inserting blinds.

10 Measures for fire detection and alarm Mobile devices that can be easily installed can be used for fire detection purposes. Fire detection and fire alarm systems with smoke detectors should preferably be used.

The installation of automatic early detection systems requires detailed preliminary plan-ning in order to actually ensure early detection on the one hand, and to limit false alarms to an acceptable level on the other hand. The components of the fire detection and fire alarm system shall have been inspected and approved by VdS.

Reasonable internal monitoring of the absorber and of the flue gas ducts shall depend on the spatial and operational conditions (e.g. air-conditioned areas, installed intermediate platform).


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Fire detection and fire alarm systems using ionisation smoke detectors have proved their worth. Monitoring levels at a distance that should mainly be determined by the arrange-ment of the internals shall be created inside an absorber. The vertical and horizontal dis-tance between the detectors should not exceed 8m and the maximum surface monitored should not exceed 60m².

Optical detectors using the transmitter/receiver principle (light barrier principle) should be used in straight ducts. The detector principle covering a whole surface/space shall be preferred due to its easy installation and its higher safety against false alarms in these lo-cations.

11 Fire fighting measures The installation of fire-fighting equipment is indispensable for controlling a developing fire, especially in the area of lined flue gas ducts and of the absorber. Since the options for fighting a fire from the outside are quite limited in most cases, suitable mobile fire-fighting equipment shall be available on site. Any existing water spray or exposure protection sys-tems in the flue gas desulphurisation plant should be integrated and used in the fire pro-tection concept.

11.1 Manual fire fighting Fire extinguishers shall be kept available at the respective workplaces. Sufficient supply of extinguishing water shall be ensured. At least one pressurised (3 bar) C-hose with a jet pipe shall be kept available for the rubber lining level or the coating section in question.

Emergency call facilities shall be provided all over the object to enable quick alarming of fire fighters (plant or public fire brigade).

Before starting any inside rubber lining or coating work, all fire-fighting equipment (such as risers and wall hydrants) shall be made operational. The workplace shall be equipped with suitable fire extinguishers.

11.2 Possible uses of plant technology

11.2.1 Protective measures for absorbers

The high fire hazard in the absorber makes the use of stationary and temporary fire ex-tinguishing devices indispensable.

For operation in line with the intended use, most absorbers (wet or spray absorbers) are already equipped with facilities that spray water in the same way as fire extinguishing de-vices. The following components can be considered in the design of fire-fighting equip-ment:

emergency nozzle spraying levels;

spray absorption levels; or

spray facilities of droplet separators.

It is recommended to keep the suspension pumping stations in operation (standby func-tion) even when the flue gas desulphurisation plant is standing still so that the top spray level can be supplied with a sufficient amount of water or suspension for fire fighting pur-poses.


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As long as the emergency nozzle spraying levels or spraying facilities of the droplet sepa-rators maintain their function, they shall either be permanently connected to the fire-fighting water mains or, in case of a fire, be supplied with water by the fire brigade, using C-type couplers.

Different technical reasons or different safety conditions can prevent a “stand-by“ function of plant technology, e.g. a release request on a plant being inspected. For this reason and regardless of any existing spray devices, special water spray fire-fighting equipment is always recommended for efficient fire fighting. This water spray fire-fighting equipment (water shield) shall be installed before starting internal rubber lining/coating work and for all other repair work in the absorber so that an efficient sprinkling density of at least 2,5mm/min is ensured on the internal vessel surface.

Horizontal spray levels in the absorber should be arranged at distances of 30m max. Nozzle spraying into the absorber shall be arranged so that the walls are sprayed suffi-ciently.

In this context, particular attention shall be paid to the creation of horizontal compart-ments inside the absorber which are set up for work safety and climatic reasons. It is necessary to install an additional water spray fire-fighting device beneath every level that is completely closed and which can prevent complete sprinkling of the inside vessel wall.

11.2.2 Protective measures for clean gas ducts Due to the shape and size of the clean gas ducts, fire fighting inside these ducts can turn out to be extremely difficult. The following fire fighting options shall therefore be examined and a suitable one selected:

Mobile water spray extinguishing equipment is installed (density of water discharge at least 2,5mm/min, relating to the inside surface) that can be triggered by detector pipework or by a fire detection and fire alarm system.

For fire fighting using high-expansion or medium-expansion foam, foam extinguishers shall be kept available at the manholes and at the inspection openings. High expan-sion foam generators or medium-expansion foam pipes can be used for these media.

12 Organisational fire protection measures The client and the contractor (plant manager and site manager) shall set up fire safety regulations in connection with the construction site regulations in good time before work starts. These regulations shall be handed over to the companies working on site and should be a contract basis. Violations of these regulations shall be punished by discipli-nary measures, e.g. by exclusion from the site.

12.1 Setting up and operation of construction site /14/ The preparatory work also includes setting up and furnishing of site accommodation (temporary buildings). The provisions of the regional building regulations shall apply /15/.

Temporary buildings, especially those made of combustible materials, shall be arranged at a sufficient distance from existing power plant areas (30m) and from one another (20m) so that in case of a fire, fire spread is prevented and sufficient areas for movement and positioning of the fire brigade are ensured.


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As an alternative, when arranging barracks in a row a fire break wall extending over the roof and the side wall shall be provided at least every 30m. Temporary buildings shall never be set up beneath pipe and belt bridges and beneath cable trays.

Storage areas for flammable liquids /16/, /17/ and for gases /18/ shall also be set up at a sufficient distance, i.e. 20m min., from existing power plant areas and from temporary buildings and marked as such. The same applies analogously to areas where combusti-ble internals are stored.

The flue gas desulphurisation plant construction site shall be enclosed in order to prevent access by unauthorised persons, e.g. by means of a safety fence. The access shall be permanently guarded.

Mobile (operational) fire loads that are not directly required for the works shall be re-moved from the work areas or be kept to a minimum. These also include aids (such as scaffolds, facing, wood, textiles and plastics) and flammable auxiliary agents (such as glues and solvents). Only half the quantity of the latter needed for a day should be stored in the work areas. Further stocks shall be stored at a safe distance from the site (at least 20m), and glues and solvent containers additionally in collecting trays.

Scaffolds and work platforms should be made of non-combustible materials (steel, alu-minium). Combustible formwork and scaffolding components shall be approved only in exceptional cases. When covering workplaces or work areas becomes necessary be-cause of weather conditions, non-combustible covers of building material class A accord-ing to DIN 4102 shall be selected for this purpose (e.g. covers made of mineral sub-stances).

The individual trades (specialised companies) shall inspect the proper condition of their work area jointly with the site management before starting work and define the limits with the respective adjacent trade. Any shortcomings relating to fire protection shall be re-corded in writing before starting work. The site management shall order these shortcom-ings to be removed without delay and confirm this step. The scope of required fire extin-guishing aids shall also be established in writing. Regardless of the specialised compa-nies’ own responsibility, the site management shall strive for participation of the public fire brigades /19/, /20/ by agreement with the plant fire brigade and the fire protection author-ity in charge.

12.2 General organisational fire protection measures The following safety recommendations shall be observed:

nomination of a responsible site manager in charge of coordinating the individual work steps;

preparation of a time schedule in order to exclude coincidence of work processes in-creasing the hazard (e.g. welding and gluing work);

safety instructions prior to starting work;

as a matter of principle, involvement of the company’s fire protection and/or industrial safety department;

- written individual permits for work processes with a fire hazard, especially in hazardous areas and plant sections;

employment of a permanent fire watch to be ensured best by the plant fire brigade;


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guard rounds during construction, maintenance and repair work shall not be left solely in the responsibility of the outside contractor, but shall be ensured by manage-rial staff (guard round records);

switching of fire extinguishing equipment to “standby” (e.g. by maintaining the func-tion of the emergency nozzle spraying level in the absorber);

making available of fire-fighting equipment in the close vicinity of the workplaces (e.g. laying out of hoses carrying water);

keeping available of fire alarm units near the workplaces (mobile automatic fire alarms, manual call points);

operational plant sections shall be protected against outside effects (e.g. by structural separations, covers made of non-combustible materials or other protective enclo-sures) and against restarting contrary to regulations;

spare parts and other flue gas desulphurisation plant accessories (such as rubber lin-ing and coating materials or fillings) shall be stored outside of the flue gas desul-phurisation plant building in order to reduce the fire load. Updated safety data sheets of these combustible substances according to the standard /21/, stating the sub-stances, the stored quantity and the storage location shall be kept available. Keeping a fire protection plan (outline drawing) available at the entrance is useful;

following an inspection, the site shall be released by the responsible site manager;

the VGB sheet M 112 /22/ shall be observed; the statements made in VGB regula-tions R 108, sections 9 and 10 “Particular measures during installation, commission-ing and inspection“ and R 128 /23/ as well as the technical rules for steam boilers TRD 460 /24/ shall be applied analogously to flue gas desulphurisation plants.

12.3 Special organisational fire protection measures for rubber lining and coating work

The following regulations shall be observed especially when handling easily combustible substances:

The explosion protection regulations /25/ shall be complied with.

In vessels and pipes, sufficient venting shall ensure that no ignitable mixture of sol-vents and air can be created. Aeration and venting shall be designed so that 50% of the lower explosion limit will not be exceeded. This measure shall be monitored by continuous measurements using a sufficient number of explosimeters and checked by the installation manager or another person in charge. It shall be ensured that when a fan fails (mechanical defect or power failure), the lower explosion limit will not be reached. Power supply and control of the fans shall be guaranteed (emergency power supply, second independent infeed).

Before starting any rubber lining work, a suitable location of the waste air blower shall be defined. Any dead flow zones detected in the course of recurring concentration measurements while executing the work shall be removed by modifying the waste air ventilation.

The waste air opening should be located several metres above the ground so that heavy gases of an explosible concentration cannot accumulate on the ground outside the vessels. Moreover, strong winds shall not influence waste air opening in such a way that venting is obstructed.

All electrical equipment used shall meet the requirements for use in explosion-hazardous areas /26/. Mobile electrical equipment shall be operated with a residual current protective device (30mA). Electrical distribution cabinets shall be installed outside the rooms or vessels.


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Vessels, apparatus and objects that may be subject to electrostatic charges shall be earthed in order to avoid ignitable discharges.

In the processing and put-down areas of easily combustible coating materials, the use of objects that can generate sparks by hitting them or when they touch one an-other is not allowed. Textiles that can become electrostatically charged (e.g. clothing made of nylon, perlon and other plastic materials) are not allowed either.

Site lights shall be set up and installed so that they cannot fall over or fall down. Combustible substances shall not be stored or put down in the close vicinity of lights.

When handling easily flammable materials, each work group shall be equipped with two PG 12 fire extinguishers and a fire extinguishing blanket. A fire extinguish-ing hose with a C-pipe or a medium-expansion foam pipe shall be laid out up to the place of work (at the vessel entry). If no sufficient extinguishing water supply is available, a PG 50 fire extinguisher shall be kept available at the entry as an alter-native. Putting the fire extinguisher into operation shall not cause a hazard to per-sons (e.g. by dry powder).

When working in vessels and narrow spaces, a guard or a fire watch shall be provided.

When working in an almost fully closed absorber, during rubber lining work or in an almost fully closed flue gas duct and during coating work, an explosion protection zone at a radius of 2m and a safety zone at a radius of 10m shall be defined around these outer shells (see figures 2 and 3).

For welding work, the safety zone shall be extended to 30m above an elevation of 5m above ground level since glowing particles, sparks etc. may spread in an uncon-trolled way.

As far as the dimensions of the explosion protection zones near the vessel entries / escape routes are concerned, a distance of 2m can also be regarded as sufficient. It shall be ensured that these access points are safeguarded by a lock in front of the access point. In addition, forced ventilation in the absorber shall reliably prevent the release of an explosible solvent/air mixture.

Welding and grinding work, open fire and smoking are not allowed in the safety zone. All combustible materials shall be removed from a suitably marked safety zone or shall be protected in specific cases.

Figure 2: Explosion protection, safety and extended safety zones around the flue gas duct


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Figure 3: Explosion protection, safety and extended safety zones around the absorber


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12.4 Complementary measures The flue gas desulphurisation plant should be integrated into the monitoring and

check service by the operating company and the plant fire brigade at the earliest pos-sible point in time.

If a works security dept. or a guard service is working on the power plant premises, check points with time clocks shall be provided especially at remote points of the flue gas desulphurisation plant area.

The power plant management shall be informed of every repair and construction ac-tivity (e.g. during inspections) and shall approve the works in writing.

After commissioning a flue gas desulphurisation plant, clear marking of the following fire protection devices and areas shall be provided:

Fire detection and fire alarm systems/fire detectors – Extinguishing sys-tems/release points

Fire-resisting closures

Emergency shut-down and/or emergency shut-off devices

Fire extinguisher locations

Non-smoking/smoking areas

Fire fighting areas

Extinguishing water withdrawing points

Fire brigade areas

Emergency exits/Escape routes

Safety areas/No-access areas

Areas of responsibility including the name of the person responsible

Pipes by content and direction of flow

The personnel operating the plant after commissioning shall be made familiar with the specific characteristics and the special hazards connected with a flue gas desulphurisation plant as early as during the construction phase and training in fire protection devices operation shall be provided.


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13 Literature /1/ VdS 2000

Brandschutz im Betrieb /2/ DIN 4102

Brandverhalten von Baustoffen und Bauteilen

/3/ VdS 2234 Brandwände und Komplextrennwände Merkblatt für die Anordnung und Ausführung

/4/ VdS 2098 Rauch- und Wärmeabzugsanlagen (RWA) Richtlinien für Planung und Einbau

/5/ VdS 2095 Guidelines for automatic fire detection and fire alarm systems Planning and installation

/6/ VDE 0833 Gefahrenmeldeanlagen für Brand, Einbruch und Überfall Teil 1: Allgemeine Festlegungen Teil 2: Festlegungen für Brandmeldeanlagen (BMA)

/7/ VdS 2001 Feuerlöscher Regeln für die Ausrüstung von Arbeitsstätten

/8/ VdS 2034 Nichtöffentliche Feuerwehren Merkblatt für die Bewertung

/9/ VdS 2092 Sprinkleranlagen Richtlinien für Planung und Einbau

/11/ VdS 2108

Guidelines for foam extinguishing systems Planning and installation

/12/ VdS 2093

CO2 fire extinguishing systems Planning and installation

/13/ VdS 2031

Blitz- und Überspannungsschutz in elektrischen Anlagen Richtlinien zur Schadenverhütung

/14/ VdS 2021

Brandschutz bei Bauarbeiten Merkblatt zur Schadenverhütung

/15/ Bauordnungen der Länder

Oberste Bauaufsicht der Bundesländer


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/16/ Verordnung über Anlagen zur Lagerung, Abfüllung und Beförderung brennbarer Flüssigkeiten zu Lande (Verordnung über brennbare Flüssigkeiten – VbF) und Technische Regeln für brennbare Flüssigkeiten (TRbF)

/17/ Technische Regeln für Gefahrstoffe (TRGS)

Ausschuß für Gefahrstoffe des Bundesministers für Arbeit und Sozialordnung (BMA)

/18/ Druckbehälterverordnung (DruckbehV) und Technische Regeln

Druckbehälter (TRB) und Druckgase (TRG) Druckbehälterausschuß des Bundesministers für Arbeit und Sozialordnung (BMA)

/19/ DIN 14095

Feuerwehrpläne für bauliche Anlagen /20/ VdS 2030

Brandschutzplan Anleitung und Hilfsmittel für die Erstellung

/21/ DIN 52900

DIN-Sicherheitsdatenblatt für chemische Stoffe Formblatt und Hinweise zum Ausfüllen

/22/ VGB-Merkblatt M 112

Brandschutzmaßnahmen in Rachgasreinigungsanlagen Technische Vereinigung der Großkraftwerksbetreiber e.V. VGB-Kraftwerkstechnik GmbH

/23/ VGB-Richtlinien R 108

Brandschutz im Kraftwerk VGB-Richtlinien R 128 Baulicher Brandschutz bei fossilbefeuerten Kraftwerken Technische Vereinigung der Großkraftwerksbetreiber e.V. VGB-Kraftwerkstechnik GmbH

/24/ Entwurf TRD 460

Anlagen zur Verminderung von luftverunreinigenden Stoffen in Rauchgasen von Dampfkesselanlagen; Rauchgasreinigungsanlagen

/25/ ZH 1/10

Richtlinien für die Vermeidung der Gefahren durch explosionsfähige Atmosphäre /26/ VDE 0170/171

Elektrische Betriebsmittel für explosionsgefährdete Bereiche


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Documents

Flue Gas Desulphurisation Plants (FGD) - vds-global.comvds-global.com/fileadmin/vds_publikationen/vds_2371en_web.pdf · Flue Gas Desulphurisation Plants (FGD) VdS 2371en : 1993-10