3　General Requirements

3.0.1　Plant layout shall comply with the following requirements：

1　Piping and Instrumentation Diagram（P&ID）；

2　Safe operation；

3　Environmental protection；

4　Plant overall layout；

5　Operation，maintenance，construction and fire fighting；

6　Reasonable land-use and reduced energy consumption.

3.0.2　Plant layout shall be determined according to the plant location in the general plot plan and the plant relative location to other related plants，tank farms，interconnecting piperacks and roads，and shall be well coordinate with the adjacent plants.

3.0.3　Arrangement for equipment，buildings and structures in the plant shall conform to the following principles：

1　Relative locations of equipment and buildings shall be determined according to information of yearly frequent wind direction.

2　Equipment restrained by process characteristics or climate conditions may be arranged in buildings.

3　Correlation between relative elevation and absolute elevation of the ground where the plant is located shall be determined according to plant vertical layout.

4　Heavy duty equipment or equipment subject to vibration shall be properly arranged according to the geological conditions.

5　Equipment，buildings and structures should be arranged on the same ground level.In case restrained by topographical conditions，control rooms，field rack rooms，substations，laboratories and office buildings shall be located on the higher ground level，while process equipment and storage tanks should be located on the lower ground level.

3.0.4　Overall consideration for equipment arrangement shall be taken to follow process flow sequence and group the same kind of equipments.Equipment should be arranged at two sides of piperack as per process flow sequence，and equipment handling corrosive，toxic and viscous fluids should be grouped separately according to the fluid properties.

3.0.5　The fire prevention spacing for equipment and buildings shall conform to the current national standard GB 50160.

3.0.6　Arrangement of equipment driven by electric power and electric equipment shall conform to the current national standard GB 50058.

3.0.7　Equipment generating noises should be arranged away from staff-concentrated place，and noise control criteria shall conform to the current relevant standard of the nation SH/T 3146.

3.0.8　Equipments，buildings and structures shall be arranged in different areas according to operation characteristics and the classification of fire-hazard.Related equipment with process requirements，such as prevention of coking and slugging，decrease of temperature drop and pressure drop and avoidance of sub reactions，may be located closely.

3.0.9　Any main equipment and its associated equipments may be directly connected or closely arranged.For example，fractionators and their overhead condensers，bottom reboilers，compressors and their knockout drums，interstage coolers.

3.0.10　Any equipment generating harmful gas，dust，odor pollutants or radioactive emission should be located away from staff-concentrated place and shall conform to environment protection regulations.

3.0.11　Equipment should be arranged in open air or half-open air，and the extent of explosion hazardous area should be reduced.The extent of explosion hazardous area shall conform to the current national standard GB 50058.

3.0.12　In addition to compliance with fire prevention and explosion protection provisions，equipment spacing shall also satisfy the following requirements：

1　Areas and accesses required for operation，maintenance，loading/unloading and hoisting；

2　Arrangement for platforms，ladders and stairs；

3　Arrangement for equipment foundations，underground piping，pipe trenches，cable trenches and water drainage pits；

4　Installation of piping and instruments.

3.0.13　If a plant is to be constructed in phase or area shall be reserved for future expansion，the reserved area shall be determined according to plant overall layout，process properties and equipment features.

3.0.14　Elevation layout of equipment shall comply with the following requirements：

1　Equipment which is not required to be elevated by P&ID should be located on the ground.

2　Towers and vessels with draw-off pumps，equipments with vacuum，gravity flow and solid unloading shall be located at proper elevation as per P&ID.

3　If the plant area is limited or economical consideration in reason，equipments may be elevated in structures.

3.0.15　Elevations of equipment foundations，locations and elevations of underground vessels for receiving liquid shall be determined according to the plant vertical layout and piping arrangement.

3.0.16　In locating equipment，buildings and structures，their foundations of underground sections shall not extend beyond the plant battery limit.

3.0.17　The areas provided for equipment maintenance in tower areas and at multi-level structures etc.shall be paved.

3.0.18　Curbs shall be provided for the areas which are potentially contaminated by flammable and combustible liquid，corrosive fluid or toxic fluid during operation or maintenance，and areas for equipment handling corrosive fluid shall be paved with corrosion-proof.Curbs shall comply with the following requirements：

1　Curb shall be at least more than 150mm above the ground within curbed area；

2　Drainage facilities shall be provided within curbed area；

3　The ground within curbed area shall be sloped to drainage facilities，and the slope should not be less than 0.003.

3.0.19　Drainage facilities provided within curbed area shall comply with the following requirements：

1　Ditches or funnels may be provided for the wastewater to drain into oily sewage system in oil contamination area；

2　Collection sumps may be provided for corrosive fluid or toxic fluid to collect and transfer in contamination area.

3.0.20　Arrangement of chimneys in the plant shall comply with following requirements：

1　Vent requirements and vent heights for flammable and harmful gases shall conform to the current national standard GB 16297；

2　Chimney should be located at one end or at the edge of the plant，and shall be positioned at the upwind side of the yearly minimum frequent wind direction in the plant；

3　Chimney top shall be more than 3.5m above the operation platforms or buildings located within an extent in 20m to the chimney，and platforms or buildings located within an extent beyond 20m to the chimney shall conform to the requirements shown in Figure 1.

3.0.21　The piping layout shall be taken overall consideration into equipment arrangement.For example，piping with specific requirements for run distance，angle and difference elevation by its fluid，and piping with high operation temperature and large diameter piping.