6.2　Planning of Plant Area

6.2.1　The planning of the plant area shall be centered on the main power building according to the principles of reasonable process flow，definite division of areas，compact and reasonable layout，and convenient extension，taking into account the functions of various production facilities and systems，local specific conditions as well as the requirements for fire protection，explosion prevention，environmental protection，labor safety，and occupational hygiene.The administration buildings and living/logistic buildings and facilities should be arranged centrally at the fixed end of the main power building to allow easy contact with production，convenient life and visually attractive arrangement.The planning of the plant area of an enterprise's self-supply power plant shall keep in harmony with that of the enterprise's workshop layout.

6.2.2　In addition to the current national standards on fire protection and environmental protection，the layout of main buildings and structures in the plant area shall also comply with the following requirements:

1　The planning of the plant area shall be determined based on the planned capacity.If the power plant is constructed by stages，the overall planning shall allow the harmony between the recent construction and long-term development.Buildings and structures shall be arranged centrally in the short term，reserving appropriate spaces for future extension.Lands shall be acquired by stages and it is prohibited to keep the land acquired in idle.

2　The main power building shall be properly located in the plant area.When once-through water supply system is employed，the turbine house should be near the water source.The main power building and chimney should be arranged on the ground area with uniform soil stratum and high bearing capacity.The fixed end of the main power building should face towards the plant access roads.If direct air cooling units are adopted，the effects of meteorological conditions on the operation of air cooling units and location of the main power building shall be considered.

3　Outdoor switchgears shall be arranged to allow convenient routing of incoming and outgoing power lines and avoid crossing.

4　The cooling tower shall be arranged by comprehensively considering the topography，geology，layout of adjacent facilities and prevailing wind direction all the year round.It should not be arranged at the extension side at the early stage of the project.For a power plant employing flue gas discharged cooling tower，the cooling tower should be arranged close to the boiler rear to allow smooth and short flue duct.And for a power plant employing mechanical draft cooling tower，the air inlet side of single-side air inlet tower should face toward the prevailing wind direction in summer，while the air inlet side of doubleside air inlet tower should be in parallel with the prevailing wind direction in summer.

5　The outdoor coal storage yard and liquid ammonia storage facilities should be located at the windward side of the all-the-year-round minimum frequency of wind direction of main buildings in the plant area so as to prevent pollution to off-site residential areas.

6　The oil supply and unloading pump house，combustion-supporting oil tank，and liquid ammonia storage facilities shall be arranged in an area independent of other production，auxiliary and ancillary buildings.If they are arranged close to rivers or lakes，measures shall be taken to prevent the liquid from leaking into the water area.

7　The discharge outlet of production wastewater and domestic sewage treated up to the standard shall be kept away from the domestic water intake.Such wastewater and sewage shall be discharged centrally at the downstream of the intake and，if not tested，shall not be discharged into the main sewerage pipeline.

8　There shall not be less than two accesses to the plant area.They shall be located to facilitate internal and external communication and separate pedestrian and freight flow.The main access should be located at the fixed end of the plant area.During construction，there should be an access dedicated for construction.In case where trucks are to be adopted for coal or ash transportation，a dedicated access should be provided.

9　The buildings（or structures）in the plant area shall be reasonable and compact in layout arrangement and spatial organization and have simple，harmonious and novel construction style and aesthetic appearance.The style and layout of buildings in the enterprise's self-supply power plant shall be in harmony with the overall environment of the enterprise.

10　The plant area of an extended power plant shall be planned and modified from an overall view according to the arrangement features of production systems in the existing power plant，making reasonable use of the existing facilities and reducing the necessity for demolition to the minimum.Moreover，extension construction shall not interfere with the normal production.

11　Auxiliary and ancillary buildings shall be of combined multi-storey structure.

6.2.3　The main buildings in the plant area should be located by taking into account such factors as sunlight，natural ventilation and natural daylighting.

6.2.4　The land-use indices of a power plant shall comply with relevant national regulations on construction of electric power projects.The building coverage in the plant area shall not be less than 35% and the greening space ratio not more than 20%.

6.2.5　The minimum distance between various buildings and structures in the power plant shall be in accordance with the requirements in Table 6.2.5.

6.2.6　The enclosure walls for the plant area shall be erected as orderly as possible on the premises of occupying the minimum land，and，unless otherwise specified，should be of solid enclosure walls not lower than 2.2m high.The on-site parts of outdoor HV switchgear area and the transformer yard shall be enclosed with fences with a height of 1.8m and 1.5m respectively.The liquid ammonia storage area and combustionsupporting oil tank area shall be arranged separately and enclosed with non-combustible solid walls not lower than 2.0m high.If enclosure walls for the plant area are used for such purpose，they shall be noncombustible solid walls not lower than 2.5m high.The combustion-supporting oil tank area shall be provided with additional fire dike or fire wall.

6.2.7　In case of power plants where air cooling units are installed，whether direct or indirect air cooling system is adopted shall be determined according to the meteorological data，topographical and geological conditions，connection of special service railway lines and conditions of the cooling tower area through techno-economic comparison.The arrangement of air cooling facilities shall comply with the following requirements:

1　The orientation of platform carrying direct air-cooling system shall be determined according to the direction，speed and frequency of wind prevailing all the year round and in summer in the platform area and on the top of steam distribution pipe，while taking into account operation safety and economy of air cooling units.It shall be oriented such that it will not be exposed to the summer prevailing wind blowing from the rear of the boiler.

2　The platform carrying direct air-cooling system should be located outside column A of the main power building.The transformer，electrical switchgear room，and oil storage tank should be arranged under the platform provided that the platform columns will not affect the installation of transformers and the accesses for installation，fire fighting and maintenance.

3　In order to minimize the length of circulating water pipeline，the indirect air-cooling tower should be arranged close to the turbine house，except when it serves as a flue gas discharged cooling tower.

6.2.8　The design of special service railways for a power plant shall comply with the current national standard GBJ 12 Code for Design of Standard Track Gauge Railway in Industrial Enterprises.These special railways shall be planned once for all and constructed by stages according to the planned capacity，coal consumption，coal unloading mode，consumption of oil for ignition and combustion supporting under low load of boilers as well as the construction needs.

6.2.9　In case of power plants where coals are transported mainly by waterway，the construction scale and plan layout of the wharf shall be planned from an overall view according to the planned capacity of the plant，natural conditions of the plant site and waterway and the conditions of coal handling facilities inside the plant，and shall satisfy the following requirements:

1　The planning and design of wharf shall comply with the current national standards GB 50192 Code for Design of River Port Engineering and JTJ 211 Design Code of General Layout for Sea Port.

2　The wharf shall be located at sections with appropriate water depth，stable waterway，weak sediment movement，smooth flow，and good geology，and should be coordinated with the on-shore elevation.

3　There shall be sufficient open water areas in front of the wharf.The distance between the wharf and cooling water intake and outfall shall be sufficient to avoid mutual effects，and shall be sufficiently demonstrated and reasonably determined through model tests.

6.2.10　The design of roads in the plant area shall comply with the current national standard GBJ 22 Code for Design of Roads in Factories and Mining Areas.

6.2.11　Traffic lane，fire lane and pedestrian way shall be provided between buildings in the power plant to meet requirements of production，living and fire protection.If it is difficult to provide ring-shaped fire lanes in power plants in mountainous area，dead end type fire lanes with a turnaround may be provided instead.The main power building，switchgear area，coal yard，liquid ammonia storage area，and combustion-supporting oil tank area shall be provided with ring-shaped fire lanes.

6.2.12　Main roads in the plant area should have concrete or asphalt pavement.

6.2.13　The width of the driving lane of an arterial road in the plant area should be 6m-7m，and that of a minor road can be 3.5m-4m.The width of pedestrian ways leading to the access to a building should match with the width of the gate of the building.

6.2.14　The vertical arrangement of the plant area shall be determined by comprehensively considering such factors as production process requirements，engineering geology，hydro-meteorological conditions，earthwork quantity and ground treatment and shall comply with the following requirements:

1　For the power plant without levee or embankment，the design elevation of the ground floor outside the main building shall be 0.5 m higher than the design high water level.For the plant area provided with levee or embankment that meets the requirements for flood protection，the elevation of plant site may be appropriately lower than the design flood level provided that reliable measures against internal water logging are taken.

2　The elevations of all buildings，structures，railway and roads shall be convenient for production，operation and maintenance.The elevations and arrangement of the foundation，pipelines，pipe supports，pipe trenches，tunnels and basements of the aboveground and underground facilities shall be planned from an overall view so as to ensure reasonable intersection，and allow convenient maintenance and extension and unobstructed water drainage.

3　The earthworks required for the current phase and extension of the project shall be minimized，the expense for foundation treatment and site preparation shall also be minimized，and the backfilled volume and excavation volume in the plant area and construction site shall be comprehensively balanced.If the backfilling and excavation quantities cannot be balanced，the places for borrowing or disposing soil shall be determined in advance.

4　The minimum slope and inclination direction of the ground in the plant area shall allow quick surface water drainage and shall be adaptable to the positions of the rainwater catch basin and gutter of the buildings，roads and ground and shall be determined according to the local rainfall amount and soil condition of the plant site.

5　The vertical arrangement of a power plant in hillside land shall reasonably utilize the landform，minimize the earthwork quantity and ensure stabilization of slope and retaining wall provided that the process requirements are satisfied.

6.2.15　If the natural slope of topography of the plant area is above 3%，stepped arrangement should be adopted.The steps shall be divided according to the production requirements and to allow convenient traffic and reasonable layout of underground facilities.At the intersection of two steps，measures to ensure slope stabilization shall be taken into full consideration based on the geological conditions.

6.2.16　The design of drainage system in the plant area shall be determined taking into account the landform，engineering geology，and groundwater level and comply with the following requirements:

1　The design of drainage system shall be fully considered according to the planned capacity and to allow smooth drainage in every phase of the project.Depending upon the project-specific conditions，the drainage system can be connected either to the main trunk pipeline well of the city-mode roadway sewage system through rainwater drainage openings，or to the highway-mode roadway rainwater drainage system through open ditches.If possible，the gravity drainage shall be adopted.For power plants in stepped arrangement，every step shall be provided with separate drainage means.For power plants in mountainous area and hill，facilities to prevent torrents from rushing into the plant area shall be provided at the boundary of plant area.

2　If the outdoor trench is higher than the design floor elevation，water drainage measures shall be taken，or drainage facilities shall be provided on both sides of the trench.

3　Separate drainage facilities shall be provided around the coal yard to prevent rainwater outside the coal yard from flowing into the coal yard，and rainwater in the coal yard from flowing out of the coal yard.Clarification tank and facilities used for removing mud coal shall be provided in the coal yard.

6.2.17　The elevation of ground level of buildings shall be determined according to such factors as the architectural function，transportation，site drainage and site geological conditions，and should be 150mm-300mm higher than the outdoor design level.In soft soil areas，the effects of the difference between indoor and outdoor settlement shall be considered.

6.2.18　Main overhead pipelines，underground pipelines and pipe trenches in the plant area shall be planned from an overall view and arranged centrally based on the planned capacity，and there shall be adequate pipeline corridor.

Overhead pipelines，underground pipelines and pipe trenches should be laid along roadway.Underground pipelines and pipe trenches should be laid outside the vehicle traffic area of roadway.

6.2.19　The arrangement of overhead pipelines and underground pipelines shall comply with the following requirements:

1　The arrangement shall ensure reasonable process flow and allow convenient construction and maintenance.

2　Any faults on pipes shall not cause secondary disaster.In particular，measures shall be taken to prevent the sewage from infiltrating into the domestic water pipes and prevent harmful or inflammable gas from penetrating into other trenches and basements.

3　The pipelines shall be protected against mechanical damage and corrosion.

4　Freezing of liquids inside the pipes shall be avoided.

5　Surface water，groundwater and water in other pipelines and trenches shall be prevented from infiltrating into cable trenches/tunnels.In addition，backflow of various types of water into the cable trenches/tunnels shall be avoided.

6　Fire walls shall be built in places where cable trenches/tunnels enter a building or at appropriate intervals and locations，and fire doors shall be provided in the fire walls for cable tunnels.

6.2.20　The horizontal distance from pipeline trench and underground pipeline to building，structure，railway，roadway and other pipelines and the vertical distance between two pipelines crossing each other shall be determined by comprehensively considering the buried depth of the underground pipeline and trench，foundation structure of building，and construction and maintenance requirements.If HV overhead lines cross over road，railway or other pipelines，a safe clearance shall be kept according to the relevant provisions.

6.2.21　Pipelines in the plant area shall be laid in accordance with the following requirements:

1　For pipelines that can be arranged overhead centrally as the condition permits，combined pipe supports（a combination of overhead pipelines，underground pipelines and pipe trenches）should be adopted；in regions where underground water level is relatively high，earth is corrosive or the embedded depth of bed rock is relatively less thus being unfavorable for construction of underground pipeline trenches，combined pipe supports should be adopted preferably.

2　The pipes delivering water for production，living and fire protection purposes and the pipes for draining rainwater and sewage water should be laid underground.

3　The pipes delivering ash，limestone slurry，gypsum slurry，hydrogen gas，compressed air，combustionsupporting oil，ammonia gas and steam should all be laid overhead.

4　The pipes delivering acid liquor and caustic liquor can be laid either in trench or overhead.If the condition permits，ash handling pipes should be laid on either low support or conduit pillow.The pipes likely to worsen situations in the event of accidents should not be laid in one trench.

5　Cables in the plant area may be buried，or laid in trench，calandria，tunnel or overhead，depending on the specific conditions.They shall not be laid with other pipes in one trench.

6.2.22　The minimum horizontal clearance between underground pipelines and between underground pipeline and building or structure，the minimum vertical clearance between overhead pipe support（or pipeline）and the railway or road it crosses over，and the minimum horizontal clearance between overhead pipe support（or pipeline）and buildings or structures shall comply with the relevant requirements in the current industrial standard DL/T 5032 Technical Code of General Plan Transportation Design for Fossil Fuel Power Plants.