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(Virtual) Xylene Fractionation Unit Life-cycle Layers

Activities (and resulting documentation) of layers 0,1,2 and 3 are normally carried out by the client who decides upon the commissioning of the engineering company to design and build the plant.

The production requirements and control requirements are passed on to the engineering company in form of a Project Specification. Also activities 19, 20, 21 (operating the plant) are client activities - except for example plant maintenance.

Identification -- by client

0. Feasibility Study and Identification of the EBE (The VXFU)

Concept -- by client

1. Definition of Business Entity's, Mission Statement, Goals etc.

2. XFU Production Policies

3. XFU Management and Control Policies

Definition (Functional Requirements)

4. XFU Production Requirements -- by client	5 . XFU Management and Control Requirements -- by client
6. XFU Production Functions	7. Management and Control Functions
8. Process Diagrams (functional requirement specification of production)	9. Functional requirements specification of the XFU's management and control

Specification (Functional Design)

10. Functional Design of the XFU's Production Equipment

11. Functional Design of Human Roles and Organisation

12. Functional Design of the XFU's Control and Management Information Systems

Detailed Design

13. Detailed Design (or specification for purchase) of XFU Production Equipment

14. Detailed Design of Human Tasks in XFU,Training Plan

15. Detailed Design (or specification for purchase) of XFU Control sw/hw and MIS sw/hw

Manifestation (Build)

16. Implementation of XFU Production Equipment as a Simulation Model (Virtual XFU)

17. Staffing, Training,of VXFU personnel

18. Procurement or implementation of XFU Control & Information System (sw/hw) (RCP); System integration.

Operation -- by client

19. Operation of Virtual XFU simulation model

20. Human Activities to Operate and Maintain VXFU

21. Operation of XFU Information and Control Systems