Advanced Distillation Final Report

The Advanced Distillation project was concluded on December 31, 2009. This U.S. Department of Energy (DOE) funded project was completed successfully and within budget during a timeline approved by DOE project managers, which included a one year extension to the initial ending date. The subject technology, Microchannel Process Technology (MPT) distillation, was expected to provide both capital and operating cost savings compared to conventional distillation technology. With efforts from Velocys and its project partners, MPT distillation was successfully demonstrated at a laboratory scale and its energy savings potential was calculated. While many objectives established at the beginning of the project were met, the project was only partially successful. At the conclusion, it appears that MPT distillation is not a good fit for the targeted separation of ethane and ethylene in large-scale ethylene production facilities, as greater advantages were seen for smaller scale distillations. Early in the project, work involved flowsheet analyses to discern the economic viability of ethane-ethylene MPT distillation and develop strategies for maximizing its impact on the economics of the process. This study confirmed that through modification to standard operating processes, MPT can enable net energy savings in excess of 20%. This advantage was used by ABB Lumus to determine the potential impact of MPT distillation on the ethane-ethylene market. The study indicated that a substantial market exists if the energy saving could be realized and if installed capital cost of MPT distillation was on par or less than conventional technology. Unfortunately, it was determined that the large number of MPT distillation units needed to perform ethane-ethylene separation for world-scale ethylene facilities, makes the targeted separation a poor fit for the technology in this application at the current state of manufacturing costs. Over the course of the project, distillation experiments were performed with the targeted mixture, ethane-ethylene, as well as with analogous low relative volatility systems: cyclohexane-hexane and cyclopentane-pentane. Devices and test stands were specifically designed for these efforts. Development progressed from experiments and models considering sections of a full scale device to the design, fabrication, and operation of a single-channel distillation unit with integrated heat transfer. Throughout the project, analytical and numerical models and Computational Fluid Dynamics (CFD) simulations were validated with experiments in the process of developing this platform technology. Experimental trials demonstrated steady and controllable distillation for a variety of process conditions. Values of Height-to-an-Equivalent Theoretical Plate (HETP) ranging from less than 0.5 inch to a few inches were experimentally proven, demonstrating a ten-fold performance enhancement relative to conventional distillation. This improvement, while substantial, is not sufficient for MPT distillation to displace very large scale distillation trains. Fortunately, parallel efforts in the area of business development have yielded other applications for MPT distillation, including smaller scale separations that benefit from the flowsheet flexibility offered by the technology. Talks with multiple potential partners are underway. Their outcome will also help determine the path ahead for MPT distillation

A nonlinear dynamic model for credit risk contagion

We consider the credit risk transfer market, where several financial agents interact with each other and generate complex nonlinear relations. All these market participants are defaultable and when one of them defaults, the credit risk contagion can be described by a nonlinear dynamic problem. We propose a particular time delay Susceptible–Infected–Recovered model to investigate and describe the credit risk contagion in the market. The time delay represents the temporary immunity time lag before a bank becomes defaultable. We analytically study the model and find the steady states according to different values of time delay and different bank support policies

A time delay model for the diffusion of a new technology

In this paper, we propose a mathematical model with time delay to describe the process of diffusion of a new technology. This model is suitable for modeling diffusion processes of all those technologies that require great initial investments and public subsidies, such as technologies used for producing renewable energy. We consider external factors, such as the government policy and the production costs, that influence the decision of adoptionofthenewtechnology.Wealsoconsidertheinternalinfluencefromadopters.The adoption process is described by a delay differential equation. The time delay represents the evaluation stage at which the potential consumers decide whether to adopt the new technologyornot.Aqualitativeanalysisiscarriedoutinordertoassessthestabilityofthe equilibriumforcertainparametersandtofindthefinallevelofadopter

A time delay model for a new technology

In this paper we propose a mathematical model with time delay to describe the process of the diffusion for a new technology. This model is suitable for modelling diffusion processes of all those technologies, such as technologies used for producing renewable energy, that require great initial investments and public subsidies. We consider external factors, such as the government policy and the production costs, that influence the decision making process for new technology adoption. We also consider the internal influence from those who already are adopters. The time delay represents the evaluation stage at which the potential consumers decide whether to adopt the new technology or not. A delay differential equation describes the process of adoption. A qualitative analysis is carried out in order to study the stability of the equilibrium for certain parameters and to find the final level of adopters.delay differential equation, innovation diffusion, global stability