Line sizing

Line sizing (Liquid Phase Case)

1. LINE SIZING Liquid Phase Case Chemical Engineer Juan Pablo Hernández Castillo

2. PROCESS ENGINEERS TASKS Process engineers play an important role in the design of plants . Some of the most common activities process engineers do are relating to : Design of pipelines Design of equipments Design of instruments , such as control and safety relieve valves . P&ID’s construction Design of control strategy of differents parts of the plant . Checking As Built’s Design of the philosophy of operation of a particular section of the plant . Among others …

3. Today , i would like to share with all of you , the steps taken into account when designing pipelines. Currently , one the most known international standard to design pipelines is provided by the American Petroleum Institute . API 14E. Recommended Practice for Design and Installation of Offshore Production Platform Piping Systems . API 14E design for the following states : Liquid phase Single Phase Gas Gas- Liquid Phase lines . DESIGN OF PIPELINES

4. Considerations API 14E stablish that in order to have a accurate pipe design , two main conditions must be met : Velocity and Pressure Drop Velocity : In order to avoid Sedimentation of particles Erosion ( due to high velocity ) 15 Pressure Drop : In order to meet pressure drop conditions . API stablish 1      

5. Flow Diagram

6. Example A process engineer is asked to design a pump which can transport water from one deposit to another .

7. Assumptions The area in which the system is located : Industry sector 1 Month = 30 days The system works 24h/30 days /1 year Average kWh ( according to CREG) =$599,722 COP Suction and discharge same pipe size Comercial Steel Schedule 40 and Schedule 80 design try Pipeline lenght of 60 ft

8. Results For Schedule 40 Comercial Steel: For Schedule 80 Comercial Steel:

9. Analysis From the previous results , it must be highlighted that the only schedule pipe which met the velocity-pressure drop requierements was the Schedule 40. Schedule 40 Despite the velocity was aceptable from 5 to 8 in nominal diameter . It was noted that the only diameter which met the requierement of pressure drop (∆P= below 0,6 psi) was the 8 in pipe. In the other hand , it was seen that the proper selection of the pipe size does affects the cost of operation . If for example : A process engineer had chosen a 6 inch pipe without taking into account the requirements , then the cost of operation would have exceed 994 USD per year of operation . Schedule 40 Although 5, 6 and 8 inch diameter did meet the velocity requirements , the pressure drop conditions were not reached . Bad decisions during the piping design and pump selection can lead to years of unnecessarily high cost of operation .

10. Schedule 40- Conditions analysis

11. Schedule 40- Cost analysis

12. REFERENCES

13. ¡THANKS FOR WATCHING! Juan Pablo Hernández Castillo Contact : Email: [email protected] Cel: [phone] LinkedIn: www.linkedin.com/in/juanhdezcastillo