Modelling, simulation and optimization perspectives of an industrial steam network - Case study at a major oil refinery on the West Coast of Sweden

CATEGORY: STEAM NETWORK
Modelling, simulation and optimization perspectives of an industrial steam network - Case study at a major oil refinery on the West Coast of Sweden

Type	Report
Author	Riccardo Subiaco
URL	Free Full Text Source:  http://publications.lib.chalmers.se/publication/235160-modelling-simulation-and-optimization-perspectives-of-an-industrial-steam-network-case-study-at-a-ma
Date	2016
Institution	Chalmers University of Technology
Report Type	Report
Abstract	Steam is a heat carrier for industrial plants that is relatively cheap to produce and distribute, compared to other heat transfer media aimed for the same temperature range. It is the most used medium in thermal power plants, but can also be used in a utility network in, for example, a refinery, where it is used to handle the heat distribution. Utility steam can be used to heat process streams up to about 250°C, while also having the ability to generate work. Management and optimization of steam networks can lead to heat, electricity and economic savings. However, many times, there are difficulties associated with data collection and measurements. As a matter of fact, some secondary process variables like the outlet temperature of a steam turbine, even though useful to check the isentropic efficiency of the machine, could not be measured. This type of lack in information brings difficulties in the plant modelling and analysis. The present master thesis, which has been carried out at the department of Energy and Environment at Chalmers University of Technology, concerns the modelling and optimization of the steam system at the biggest refinery of Sweden. By using engineering and thermodynamic knowledge, a model of the steam network is developed, first in spreadsheet databases, and then aided by a proper modelling software. Assumptions and thermodynamic relations are used to model the different components that the steam system is composed by and to calculate missing values. Several steady state simulations are made with the model. For each of them a comparison with the real behavior of the system is made by connection of the software output to a validation spreadsheet through a plug-in. Moreover, once the reliability is tested, examples of how the model can be used for analysis of energy retrofit measures are presented. Finally, an economic optimization of the system operation for a given set of inputs is carried out and its results are analysed.

An Optimization Approach To Refinery Steam Management With Consideration Of Co2 Emission

CATEGORY: STEAM NETWORK 
An Optimization Approach To Refinery Steam Management With Consideration Of Co2 Emission

Type	Journal Article
Author	Mohammad Reza Jafari Nasr
Author	Majid Amidpour
URL	Free Full Text Source:  http://www.sid.ir/en/VEWSSID/J_pdf/54000420140108.pdf
Volume	4
Issue	1
Pages	73–84
Publication	Journal of Petroleum Science and Technology
Date	2014
Abstract	The importance of energy crisis and global warming necessitates presenting strategies in order to decrease the amount of emissions as well as fuel consumption in large and complex industries such as refineries and petrochemical industries. Refinery steam networks are typically regarded as units which consume enormous amounts of fuel. In this paper, the steam network of Tehran Oil Refinery is considered as an industrial case study. Then, various scenarios are proposed to modify the network. In this regard, the network and suggested scenarios are initially modeled into STAR software environment. Next, they are simulated to estimate process parameters and costs. Afterwards, each scenario is separately optimized and, after comparison, the best scenario is chosen from the viewpoint of total annualized cost (TAC). The objective function of optimization is to minimize TAC. At the second stage, the amount of carbon dioxide production is calculated for all the proposed scenarios, before and after optimization. In addition, the tax of production (Kyoto Protocol) is added to the TAC of each scenario. Since in this version of STAR software, the effects of CO 2 emission have not been taken into account, a combination of the results of TAC in the software considering CO 2 and its effect on TAC has been considered as a new investigation. In fact, both economical and environmental issues are taken into account. Moreover, the scenarios are simultaneously compared with each other and the best scenario is chosen with considering carbon dioxide taxes .

Optimization of a steam Network.

CATEGORY: STEAM NETWORK
Chemical Engineering. Dec2013, Vol. 120 Issue 12, p54-59. 6p.
Optimization of a steam Network.
Reddy, C. C. S. (1)
cs6_reddy@yahoo.co.in
Naidu, S. V. (1)
profnaidu90@gmail.com
Rangaiah, G. R. (2)
chegpr@nus.edu.sg
1 Andhra University
2 National University of Singapore
Abstract:
Offers a spreadsheet-based optimization model for a steam network in a petroleum refinery. The spreadsheet-based approach provides the flexibility to realistically evaluate a steam network, without the constraints and licensing fees incurred by using commercial process-simulation software.
Authors stress the importance of proper configuration of steam-turbine drivers which affects power generation in petroleum refineries. The spreadsheet provides the flexibility to evaluate a steam network, without the constraints and licensing fees incurred by using commercial process-simulation software.
Full Text Source (Subscription or Fee): http://www.che.com/processing_and_handling/thermal_and_energy_mgmt/boilers_and_steam_handling/Optimization-of-a-Steam-Network_11239.html