Riju De (124020012)

rijude51@gmail.com

Research title:

Model based control of transesterification of algal lipids for biodiesel production

With the advancement of research studies in the field of biodiesel production from algal lipids, transesterification reactions are gaining much attention towards the production of biodiesel carried out in various kinds of reactors namely batch reactors, CSTRs and packed bed reactors (PBR). However, most of the literature studies have reported the frequent utility of batch reactors for performing transesterification reactions at industrial scale which will lead to improved biodiesel yields. In context to this study, process engineers are challenged with the task of mathematical modelling of these reactors including the kinetic study associated with the transesterification reaction as well to develop the control strategies that are needed in order to have a check over the highly non-linear complexities associated with the batch processes and to account for time varying dynamics involved during the biodiesel production.

Biodiesel is usually obtained via a transesterification reaction between algal oil containing free fatty acids (FFA) or triglycerides and generally methanol in presence of an acidic or alkaline catalyst like sodium methoxide at about 60-70 degrees centigrade. Main factors which are affecting the biodiesel yield are effect of temperature, effect of stirring, methanol to algal oil ratio, weight and concentration of the catalyst etc. We need to ensure the optimal values of these parameters for obtaining better biodiesel yield. Under the present research work, studies will be undergone regarding the control of parameters like temperature of the batch transesterification reactor, concentration of triglycerides in the feed stream under deterministic or might be in stochastic mode. Quality control can be achieved only by focusing on several aspects concerning design and development of control strategies namely optimal control based on maximum principle formulation which includes the optimization objectives such as maximization of the concentration of methyl esters (Biodiesel), minimizing batch reaction time and maximizing the overall profit. Multivariable adaptive control schemes combined with PID tuning based internal model control (IMC) will be adapted to implement the online measurement of the control variables like temperature of the reactor, temperature and flow rate of the coolant in the reactor jacket, concentration of diglycerides and monoglycerides along with the concentration of methanol. A laboratory scale batch type transesterification reactor will be set up and batch reaction experiments will be undergone for the purpose of model validation in comparison with the simulated control parameters obtained from the designed model under investigation.

Advisor: Prof. Sharad Bhartiya and Prof. Yogendra Shastri

Academic background:

B.Tech (chemical engineering) in 2010 from Heritage Institute of Technology, Kolkata

ME (chemical engineering) in 2012 from Jadavpur University, Kolkata

Research Interest: Chemical process control, model predictive control, optimisation, mathematics

Shalmali Patkar (09D11008)
shalmali.patkar@iitb.ac.in

Research title:- Synthesizing Explicit Model Predictive Control Algorithms

Advisors:- Prof. Sharad Bhartiya and Prof. Mani Bhushan

Academic Background:
Dual Degree (B.Tech + M.Tech) in Chemical Engineering, IIT Bombay

Research Interest:
Controls, Optimization, Computational Methods

Kavitha M

Research Title: Optimization and Monitoring of Fed Batch Fermentation

To minimize the effect of catabolic repression, fermentation processes are operated in fed batch mode using complex media. Due to lack of reliable process models, model based feeding recipes have not been reported. We optimize the feeding recipe in complex media and solve this using quadratic programming. Strategy is to develop optimization of fermentation processes for which reliable process models are available.

Advisors: Prof. Sharad Bhartiya and (Dr. VRC Murty (MIT))

Academic Background : B.E Biotechnology Engineering M.Tech Biochemical Engineering

Research Interest: Modelling and simulation, Optimization

Pratik Vinayak Gholkar

Research Title: Modelling and Simulation of Hydrothermal Processing of Microalgae for Biodiesel Production

Extraction of crude oil from algae is crucial step in processing algae for biodiesel production. Hydrothermal Processing is one of the ways of extracting oil from algae which is cost effective compared to other processes employed today. We focus on process modelling of hydrothermal process to predict the yield form the algae if its composition is known.

Advisors: Prof. Sharad Bhartiya, Prof. Yogendra Shastri and (Dr. VRC Murty (MIT))

Academic Background : B.E Biotechnology Engineering M.Tech Biochemical Engineering

Research Interest: Modelling and simulation, Optimization

Pinku Jojan(123230002)

pinkujojan@sc.iitb.ac.in

Project Title-Control of non-minimum phase processes

Multivariable systems with significant amount of interaction between various inputs-outputs, considerable time-delay & RHP zeros pose a good challenge for the control system design. The design challenge increases further if one considers the uncertainty in various system parameters such as gain, time-constant, amount of interaction, RHP zero location etc. Several control design methods are found in literature which can be applied to handle such systems, but a systematic comparison and evaluation of such techniques on a single class of problem is not found. The project aims in a systematic comparison of different multivariable control techniques on quadruple tank system (system with RHP zero) and on shell heavy oil fractionator (system with large time delays)

Advisor-Dr Sharad Bhartiya

Academic background

B Tech in Applied Electronics and Instrumentation from University of Kerala in 2012

M tech in Systems and Control Engineering, IIT Bombay in 2014(expected)

Research interests

Process control, Embedded control

Hariprasad K (09402603)

hariprasad.k@iitb.ac.in

Research title: Modeling and stabilizing MPC of switched systems

Switched systems represent a class of hybrid dynamical systems wherein occurrence of a discrete event causes the evolution of the continuous states to switch from one operating mode to another. Most modeling formalisms for hybrid systems are based on linear dynamics along with the switching logic and neglect nonlinearities which may exist in each mode. A systematic development of an algorithm that provides a guide to the questions of how many such linear models should be used and their locations in the hybrid state-space with the help of tool from artificial intelligence and control theory.  For control of switched systems, the MPC problem requires an on-line solution of a Mixed Integer Program whose solution complexity increases exponentially with problem size . A novel MPC formulation, which enables tuning the trade-off between the complexity of the control algorithm with the optimal performance of the closed-loop system while ensuring stability to address this problem. Current research focus to robustify the proposed MPC frame work using the ideas of robust tube MPC.

Advisor: Prof. Shard Bhartiya

Academic Background:

 B.E. (Chemical Engg.) in 2006 from Kerala University

 M.Tech. (Chemical Engg.) in 2008 from National Institute of Technology, Tiruchirappalli

Work Experience

Process Engineer, General Electric Energy (2008-2009)

Publications

• Hariprasad, K., Bhartiya, S., Gudi, R.D.,A gap metric based multiple model approach for nonlinear switched systems ,Journal of Process Control 22 (9) , pp. 1743-1754, (2012).
• Hariprasad, K.H., Bhartiya, S., Gudi, R.D. ,A multiple linear modeling approach for nonlinear switched   systems,2012,IFAC Proceedings Volumes (IFAC-PapersOnline) 8 (PART 1) , pp. 63-68

Research Interest

Hybrid systems, Model based control, Optimization, Mathematics.

The near-integrating control behaviour in osmoadaptation in yeast (with Prof. K.V. Venkatesh): The osmoadaptation system in yeast upregulates the HOG pathway as a means of mediating osmotic shock. The HOG system in turn turns on glycerol synthesis, an osmolyte, that helps the cell to recover its volume and can subsequently resume cellular functions. The recovery of the cell volume is achieved through a near-integrating regulation strategy. This work delineates the existence of the near-integrator in the overall osmotic response system

Cell cycle regulation of S.Pombe (Prof. K. V. Venkatesh)

Growth and division of cells are highly integrated and regulated through cell signaling. The period between each cell division along with mitosis (cell division) is known as a ‘cell cycle’. Cell cycle events are governed by highly integrated signaling pathways and existence of several natural checkpoint mechanisms represents the level of regulation adopted by individual cells. Uncontrolled/Irregular cell cycle events play an important role in the development of genotoxic diseases such as cancer. Behavior of a cell is reflection of its environmental conditions which are interconnected in cell cycle regulatory pathway. The mechanism of cell cycle regulation is found conserved in all eukaryotes. The molecular mechanism of cell cycle regulatory network includes enzyme mediated phosphorylation-dephosphorylation cycles, protein-protein interactions, protein- DNA interactions, as well as external signals. Existence of several multiple feedback and feed forward loops for controlling the cell cycle events have been identified in literature. Furthermore, the activation/inactivation of these loops are also driven by other signaling pathways. But how these interactions contribute in maintaining the cell physiology is unclear. System level study of these networks will reveal the coordinated regulatory mechanisms adopted by the cell for different environmental conditions and unexpected stimuli. Our current work involves analysis of such regulatory networks in yeast by the application of mathematical modeling as a tool.

Tryptophan System (with Prof. K.V. Venkatesh)

Biological systems respond appropriately to a variety of environments representing complex systems with rich physiological behavior. Quantitative models can be used to identify the design components that result in the system complexity. In this work, we have represented the tryptophan system by a reduced model which, however, highlights the regulatory motif. The tryptophan can be conceived of processes in series with a uniqe regulation at three distinct points using a single measurement. This multiple feedback loop motif enables the system to rapidly synthesize tryptophan when faced with severe starvation to a sluggish shut off of the system when exposed to a medium replete with tryptophan. Our analysis also shows that enzyme inhibition does not play a role under severe starvation and plays a marginal role in increasing the rate of repression when the cells are exposed to well-fed conditions. Furthermore, the multiple feedback loop system is robust to parametric variations relative to a mutated single feedback loop system. A system level analysis shows that the beneficial properties of the tryptophan system are a result of the regulatory design and can be preserved over systems of engineering interest such as control of level or pH in tanks in series system

GAL System (with Prof. K. V. Venkatesh)

The GAL system in yeasts Saccharomyces cerevisiae has evolved to utilize galactose as an alternative carbon and energy source, in the absence of glucose. We have developed a dynamic model of the GAL system and linked it with growth. The developed model predicts the importance of nucleocytoplasmic shuttling and autoregulation of regulatory gene GAL80 as noted in literature. The model also captures the experimental observation that in absence of galactose, GAL3 oversynthesis can induce the GAL system. The work will also identify the relationship between the regulatory motifs of the GAL system in different yeasts and the niche that each of the designs provides to the organisms.