Busalla, Italy
Busalla, Italy

Time filter

Source Type

Cucek L.,University of Maribor | Mantelli V.,IPLOM SpA | Yong J.Y.,University of Pannonia | Varbanov P.S.,University of Pannonia | And 2 more authors.
Chemical Engineering Transactions | Year: 2015

This contribution presents the application of a novel three-step procedure for the retrofitting of large-scale heat exchanger networks (HENs) under fixed and flexible designs of existing Total Sites (TS). The entire procedure for HEN retrofitting within the analysed industrial TS consists of three steps: i) targeting and identification of the potential for improvement; ii) identification and selection of feasible and profitable alternatives for modifications, and iii) performing detailed HEN retrofit designs on the reduced spaces of alternatives. The search for retrofit modifications was performed by the economic objective by considering trade-offs between investment cost (heat exchanger area and piping) and savings in energy cost. The first targeting and second pre-screening steps were performed using the software tool TransGen, and the third synthesis step using software tool HENSYN. The novel three-step procedure was applied on an existing refinery TS. Copyright © 2015, AIDIC Servizi S.r.l.,.

Yong J.Y.,University of Pannonia | Nemet A.,University of Pannonia | Varbanov P.S.,University of Pannonia | Klemes J.J.,University of Pannonia | And 3 more authors.
Chemical Engineering Transactions | Year: 2015

Waste heat streams are often neglected due to their comparatively low temperatures. However, they can still be utilised by retrofitting existing heat exchanger networks (HEN). Traditionally Pinch Analysis has been used to set heat recovery targets and these can be used as indicators for the retrofit. However, when an existing HEN contains a number of non-optimally placed heat exchangers, major topology modifications may be needed. As a result it may be more economic to achieve heat recovery smaller than the Pinch targets. In some cases exploiting or constructing utility-exchanger heat paths may be too costly and waste heat utilisation for added value side-product should be considered. In this paper the problems in retrofitting a HEN for utilities usage reduction are discussed. Additionally, HEN modification analysis is performed aiming at generating hot water as the value-added product. As the operating conditions vary, the modified network should also be flexible. These issues are addressed by a procedure development presented in this work, where different arrangements of HEN for modification are evaluated. The developed methodology is applied to a case study. Copyright © 2015, AIDIC Servizi S.r.l.

Cucek L.,University of Maribor | Yong J.Y.,University of Pannonia | Mantelli V.,IPLOM SpA | Vocciante M.,University of Genoa | And 4 more authors.
Chemical Engineering Transactions | Year: 2014

The procedure of data acquisition under uncertain operating conditions is presented when retrofitting existing plants and Total Sites (TSs). Heat Integration (HI) and TS Heat Integration (TSHI) are performed within larger-scale industrial plant. Several studies exist regarding performing HI and TSHI under fixed conditions, both for grassroots designs (minimum energy requirement designs) and for retrofits. They have been some studies published only, which have completely address how to perform internal plant HI and TSHI when the fluctuation of operational conditions are considered at the larger scales, such as within petrochemical plants. The data acquisition for HI and TSHI under varying operational conditions still needs more attention. Those two issues are tackled by the presented work. Copyright © 2014, AIDIC Servizi S.r.l.

Agency: European Commission | Branch: FP7 | Program: CP | Phase: ENERGY.2011.8.1-2 | Award Amount: 7.37M | Year: 2012

The overall objective of EFENIS is to facilitate and accelerate a move to low carbon manufacturing processes and site management by deployment and demonstration of innovative energy management systems and enabling efficiency technologies, which extend the scope of energy management outside the boundaries of a single plant to total site and then beyond the total site to district heating/cooling systems. The potential is demonstrated across a selection of the EUs most energy-intensive sectors thereby enabling integration across industries and processes while at the same time ensuring wide-spread deployment post-project. The EFENIS project will significantly advance the state-of-the-art with regards to site optimisation and Energy Management Systems. Currently, no deployed solution with a similar holistic scope exists. The major novelty of the project will be the creation of the foundation required for comprehensive, high-impact industrial deployment of energy systems based on Total Site Integration approach in the target industries and subsequent commercial exploitation. The project is focused on allowing integration of the developed technologies and solutions to both new designs and as retrofits to existing sites to ensure fast, widespread and cost-efficient industrial deployment. Until now, both technical and non-technical barriers have prevented the exploitation of this potential.

Vocciante M.,University of Genoa | Mantelli V.,IPLOM SpA | Aloi N.,IPLOM SpA | Reverberi A.P.,University of Genoa | Dovi V.G.,University of Genoa
Chemical Engineering Transactions | Year: 2014

Temperatures and flow rates are the most frequently measured variables in industrial processes. They generally form the basis of data reconciliation based on mass and energy balances. While flow rate data rectification is routinely carried out using rigorous linear models of mass balances, energy balances, necessary for the reconciliation of temperature values, introduce two main difficulties. Indeed the presence of the product of two variables that need reconciling (temperature and flow rate) changes the original linear equations into a system of bilinear equations. Additionally energy balances are subject to modelling errors due to the presence of parameters (specific heats, latent heats, heats of reaction). The uncertainties on these parameters can affect the reliability of the data reconciliation considerably. It is shown in this article that interval analysis can provide a useful tool for reducing the sensitivity of the reconstructed values of the process variables. An important simple case is examined for illustration purposes. Copyright © 2014, AIDIC Servizi S.r.l.

Vocciante M.,University of Genoa | Mantelli V.,IPLOM SpA | Aloi N.,IPLOM SpA | Dovi V.G.,University of Genoa | Reverberi A.P.,University of Genoa
Clean Technologies and Environmental Policy | Year: 2014

The goal of flow rates reconciliation was to adjust measured values and estimate unmeasured streams so as to balance both measured and unmeasured values, identify gross errors and detect leaks and losses. Thus, data reconciliation plays a key role in the monitoring of industrial plants for the early detection of critical events which might cause environmental and economic damages, and it is,therefore, an essential component of any clean technology process. Consequently, any method that improves the accuracy of the reconstructed data by considering more realistic assumptions on the statistical nature of the data can add considerably to the overall reliability of the process. The reconciliation procedure is statistical in nature and requires adequate information on the structure of the random errors of the flow rates measured. A frequent assumption is the homoscedasticity and the independence of the errors affecting different streams. This assumption leads to efficient algorithms based on advanced linear algebra decompositions, such as QR or Singular Value Decomposition, but it frequently leads to biased estimates, especially when the values of flow rates vary over two or more orders of magnitude. The goal of this article was to show the importance of considering general heteroscedasticity when reconciling flow rates. Errors are supposed to be normally distributed according to εi≅N(0,σ0Li 2 whereLiis the measurement of the ith flow rate and θ | σ 0, η is a set of two parameters to be estimated along with the adjustments to the measured flow rates. Therefore, the overall variance-covariance is characterised by 3 parameters σ 0, η and the correlation factor among measurement errors ρ. The algorithm here proposed is based on conditional optimality, and it carries out the whole optimisation in terms of the parameters θ only, the unknown adjustments being expressed at each iteration as functions of θ. © 2014 Springer-Verlag Berlin Heidelberg.

Nemet A.,Center for Process Integration and Intensification 2 | Klemes J.J.,Center for Process Integration and Intensification 2 | Varbanov P.S.,Center for Process Integration and Intensification 2 | Mantelli V.,IPLOM SpA
Frontiers of Chemical Science and Engineering | Year: 2015

Heat Integration has been established over the last decades as a proven chemical engineering methodology. Two design implementations are often used in the industry: grassroots and retrofit. Although various methods have been developed for retrofit, it still needs more development to ensure simultaneously thermodynamic feasibility and economic viability. In this paper, a novel graphical approach has been developed to facilitate the understanding of the current situation and scope of improvement. The Retrofit Tracing Grid Diagram presents all streams and heat exchangers in temperature scale and the heat exchangers are clearly separated from each other, enabling clear visualisation of the current state. The tool incorporates the previously developed Cross-Pinch Analysis as well as path approach for retrofit. Additionally, the non-vertical heat transfer can be evaluated. The application of the developed tool has been validated on an oil refinery case study. The applicability of the tool is evident as it can reveal additional options for modification that none of the previous methods considered. [Figure not available: see fulltext.] © 2015, Higher Education Press and Springer-Verlag Berlin Heidelberg.

Loading IPLOM SpA collaborators
Loading IPLOM SpA collaborators