Our client is a large food processing company, which is outsourcing engineering design. Your company has won the bid to work on the design of the temperature control system around a steam-heated heat exchanger. The client will have a boiler using natural gas to create medium pressure steam (150 psig) available through a header. The resulting condensed steam will naturally return to the boiler through the planned pipe network, which will operate at 120 kPa.
The client uses a central glycol loop throughout the plant to add or take away heat when needed at various different unit operations. The glycol must be maintained at a temperature of 110°C but due to changing heat loads in the plant the glycol temperature varies between 30°C and 85°C. The flow rate of the glycol is maintained constant at 1.1 kg/s.
Design a steam-heated heat exchanger as well as the necessary control system that will suit the need of the client. Your report must include a description and reasoning of the proposed system, schematic of the heat exchanger, piping and instrumentation diagram (P&ID), specifications of the control equipment and estimate of the capital cost.
The necessary calculations (dynamic modeling - including Polymath, MATLAB or Python code, tuning, costing) must be present in the appendix.
Department of Chemical Engineering (Design of system and open loop model)
-Suggest a minimum of two possible feedback control schemes and give reasons for your final choice. Present a P&ID diagram of your proposed system.
-Design the heat changer using your heat transfer knowledge (this includes its size, material of construction etc.). Include a schematic of the proposed heat exchanger as well as specifications for sensors and control valve.
-Develop an open-loop dynamic model for your proposed system using the software package of your choice. Predict the behavior of the outlet temperature in the event of a step change in the glycol temperature.