Government Engineering College, BharuchChemical Engineering Department
Expert talk Title: ‘Rules of Thumb in Chemical Engineering ’
Name of Expert: Ms. Dhruti Mehta, Process Engineer, Technical Services Department, GNFC, Bharuch
Date of Expert talk: 01/02/2020
Time: 3.00 pm -4.00pm
Faculty Co-Ordinator: Dr. Naina H. Tahilramani (Asst. Prof. – Chemical Engg.)
No. of students: 35 (4th and 6th Semester)
Speaker Profile:
Ms. Dhruti Mehta has passed out B.E. Chem. From VGEC Chandkheda Gandhinagar in 2015 and Masters of Business Administration M.B.A. in operations Management and Supervision in 2017 from Jaipur National University Jaipur. She has also done Post Graduate diploma in environmental technology and management (PDIETM)Environment management First class with Distinction in 2019.
She has worked with DIC India Limited and Lupin for five months and six months respectively. She is Process Engineer posted in technical service department of GNFC Bharuch Since March 2016.She is Involved in various modification schemes raised by plant related to environment, production, operational ease etc and check its feasibility and carry out various design related calculations. She is working with softwares like HTRI, Aspen+, chemcad, scinet and SAP also.
Expert lecture description:
Expert talk was organized by Chemical Engineering Department, GEC Bharuch on “Rules of Thumb in Chemical Engineering’’.
Following topics were covered in Expert lecture.
• Various components of pumps and cooling tower
• Classification, application and selection of pump
• Rules of thumb while operating cooling tower
• Various operational problems in cooling towers and pumps
In the expert lecture, Ms. Dhruti Mehta explained the importance of Rules of thumb in process Equipment Design. She has discussed about NPSH, Cavitation and working of pumps. She explained selection criteria of pumps and cooling towersfor various industrial operations with various case studies.Students were able to understand the Rules of thumb in the field of Chemical Engineering.
Some important Rules of thumb are
1. liquid control valve sizing :No viscosity correction necessary if viscosity is less than or equal to 20 centistokes
2. For Safety Relief Valves :
The maximum pressure from an explosion of a hydrocarbon and air is 7 x initial pressure, unless it occurs in a long pipe where a standing wave can be set up. It may be cheaper to design some small vessels to withstand an explosion than to provide a safety relief system. It is typical to specify ¼” as minimum plate thickness.
3. For Heat Exchangers : Fixed tubesheet design of shell and tube heat exchangers don’t allow too high a temperature difference between tubeside and shellside without providing a shellside expansion joint. Assume the tubes are at tubeside bulk temperature and the shell is at shellside bulk temperature.
4. For thermosyphon reboilers: Never use inclined piping for two-phase flow in a process plant. This is particularly true for reboiler return piping. Use only horizontal or vertical runs. If the reboiler heating medium is condensing steam, provide a desuperheater if the superheat is more than 40-60°F
5. Dynamic type pumps obey the affinity laws:
• Capacity varies directly with impeller diameter and
• Head varies directly with the square of impeller
• Horsepower varies directly with the cube of impeller diameter and speed.
Glimpses of Expert talk.
