Petros Pilavachi

• Professor Emeritus PhD, DIC, MSc, DIC, MEng, CEng, FIChemE
• University of Western Macedonia

In Greece today, only biodiesel is produced to cover domestic consumption requirements. Next-generation biofuels are not produced in an industrial scale except in the context of research programs and industry partnerships with the academic community and research institutions. In this paper nine next generation biofuels are proposed to decarbonize t...

In this paper, a number of scenarios to decarbonize the Greek road transport sector are modeled using the Long-range Energy Alternatives Planning (LEAP) software for a variety of alternative technologies and fuels. Both light duty and heavy duty vehicles are considered. The scenario analysis time span covers years 2010–2050 with 2010 as the baselin...

Lignocellulosic biomass contains small amounts of alkali and alkaline earth metals, which may volatilize during the in situ catalytic pyrolysis of biomass and deposit on the catalyst, affecting its properties. In addition, due to the presence of steam in the process and exposure of the catalyst to high temperatures, hydrothermal deactivation also p...

This paper evaluates next generation biomass derived fuels for the transport sector, employing the Analytic Hierarchy Process. Eight different alternatives of fuels are considered in this paper: bio-hydrogen, bio-synthetic natural gas, bio-dimethyl ether, bio-methanol, hydro thermal upgrading diesel, bio-ethanol, algal biofuel and electricity from...

In this study, thermogravimetric (TG) analyses, along with thermal and catalytic fast pyrolysis experiments of cellulose, hemicellulose, lignin and their mixtures were carried out in order to investigate their pyrolysis products and whether the prediction of the pyrolysis behavior of a certain lignocellulosic biomass feedstock is possible, when its...

In developed countries, the quality of life is of first priority and an overall assessment of power plant impact on the living standard requires a multicriteria analysis of both positive and negative factors incorporating uncertainty in criteria performance and probability assessment of weighting factors. This study incorporates PROMETHEE II to ass...

This paper studies European Union (EU) legislation on private law relations for organizations operating in the internal electricity and gas market in medium and small size Member States. It consists of the analysis of both the EU primary (Treaties) and secondary (directives and regulations) legislation. A survey was sent to organizations operating...

This paper aims at estimating the potential of PV systems applied on buildings (BAPVs) within a typical Greek building block. For the purpose of the study a block located in the municipality of Thessaloniki in northern Greece was chosen. The block consists of multistory residential buildings of various heights and represents the typical Greek build...

This paper evaluates alternative fuels for the Greek road transport sector, using the Analytic Hierarchy Process. Seven different alternatives of fuel mode are considered in this paper: internal combustion engine (ICE) and its combination with petroleum and 1st and 2nd generation biofuels blends, fuel cells, hybrid vehicles, plug-in hybrids and ele...

Many European states support Combined Heat and Power (CHP) investments and provide better selling tariffs for the electricity produced. In this paper, a model was developed that can help energy planning and decision-making for CHP investments in an unstable energy market. The model uses as variables state subsidies, natural gas and electricity sell...

An economic assessment between lignite and biomass integrated gasification combined cycle power plants (IGCC and BIGCC respectively) for power generation was carried out. The two alternative power plants are presented together with the selection of the appropriate equipment. An economic evaluation was carried out for the two power plants, taking in...

In-situ catalytic upgrading of biomass fast pyrolysis vapors was performed in a fixed bed bench-scale reactor at 500°C, for catalyst screening purposes. The catalytic materials tested include a commercial equilibrium FCC catalyst (E-cat), various commercial ZSM-5 formulations, magnesium oxide and alumina materials with varying specific surface area...

A model predicting 12 properties of diesel - biodiesel mixtures was developed. This was based on existing correlations capable of providing quality characteristics for the mixtures. The model was also used to maximize the biodiesel fraction in the diesel-biodiesel mixtures, while taking into consideration all product quality specifications as they...

This paper studies the electricity production system of the Greek Interconnected Electric Production System using a model created with the software package WASP-IV. The period of study is from 2009 to 2030. It consists of three scenarios using three different criteria: energy, environmental and economic. The three scenarios are the business as usua...

Hydrotreating of waste cooking oil (WCO) was studied as a process for biofuels production. The hydrotreatment temperature is the most dominant operating parameter which defines catalyst performance as well as catalyst life. In this analysis, a hydrotreating temperature range of 330-398 degrees C was explored via a series of five experiments (330, 3...

This paper deals with the economic analysis and evaluation of various energy saving measures in the building sector, focusing on a domestic detached house in Greece, i.e. in a typical Mediterranean climate. In order to detect the energy saving measures that, in addition to energy benefits, can also provide economic profits, the study examines the f...

This paper evaluates nine types of electrical energy generation options with regard to seven criteria. The options use natural gas or hydrogen as a fuel. The Analytic Hierarchy Process was used to perform the evaluation, which allows decision-making when single or multiple criteria are considered.The options that were evaluated are the hydrogen com...

In this paper, seven common hydrogen production processes are evaluated using the Analytic Hierarchy Process (AHP) in respect to five criteria. The processes to be evaluated are steam methane reforming (SMR), partial oxidation of hydrocarbons (POX), coal gasification (CG), biomass gasification (BG), the combination of photovoltaics and electrolysis...

This paper presents the energy policy of the Republic of Cyprus government controlled areas from 1960 till 2006. It describes the sectors of electricity, petroleum, natural gas and renewable energy sources. It also deals with the marine layers of oil and with environmental aspects.The energy policy of Cyprus is harmonized with that of the European...

Complexity of power plant evaluation is steadily rising, as more criteria are involved in the overall assessment while evaluation data change rapidly. Apart from evaluating several aspects of power plants separately, a multicriteria analysis based on hierarchically structured criteria is necessary, so as to address the overall assessment of power p...

Ten types of power plant were evaluated as to their impact on the living standard. Power plant evaluation incorporates a number of criteria that can be assessed either objectively or subjectively. Objective assessments are usually quantitative and are based on real data, while subjective assessments are rather qualitative and derive from decision m...

Biomass-derived liquid bio-fuels are being promoted as a major feasible fuel alternative in the European Union, in order to reduce Europe's transport dependency on crude oil. In particular, liquid bio-fuels if used in internal combustion engines can substitute a considerable amount of conventional fuels. These bio-fuels include conventional bio-eth...

Various energy-modelling activities are pursued by public authorities, private companies and research institutes with the aim to provide energy forecasts and to assess the impact of energy and environmental policies. Nevertheless, no ex-post evaluations of the results of these modelling activities have been carried out at the European Community lev...

Decision making methods are used as a tool for the selection of alternatives to be evaluated on the basis of several criteria. Evaluation of the potential routes for natural gas supply to the Southeast and Central European countries is studied using single and multi-criteria evaluation. The potential options included in this analysis are the: Yamal...

The purpose of this study is to evaluate 10 types of power plants available at present including fossil fuel, nuclear as well as renewable-energy-based power plants, with regard to their overall impact on the living standard of local communities. Both positive and negative impacts of power plant operation are considered using the analytic hierarchy...

Non-nuclear power plant emissions are of great concern to the public and to scientists alike. As energy demand tends to rise rapidly, especially in the developing countries, the negative effects to human health and to the environment from gaseous emissions together with hazardous particulate matter released by power plants can no longer be ignored....

The need for diversification of energy sources is an immanent goal in long term energy strategy. In particular, this is of great impor-tance for the natural gas supply. In this respect, evaluation and assessment of potential natural gas resources and their relation to con-sumers is of great importance. The natural gas supply in Europe is one of the...

Geologically estimated natural gas resources are 500 Tcm. With the advance in geological science increase of estimated resources is expected. Natural gas reserves in 2000 have been proved to be around 165 Tcm. As it is known the reserves are subject to two constraints, namely: capital invested in the exploration and drilling technologies used to di...

Several Combined Heat and Power (CHP) system options have been considered for evaluation with respect to the end-user requirements. These included Internal Combustion Engines (Otto and Diesel), Gas Turbines, Steam Turbines and Combined Cycles covering a wide range of electrical output. Data have been obtained from literature and the CHP systems hav...

This paper presents the energy policy of Greece and deals with four energy sectors i. e. petroleum, natural gas, electricity/lignite, and renewable energy sources. Each of these sectors is described and its present state is presented. The Greek national strategy in each energy sector is examined while its international policy is discussed. The obje...

In this paper, the main principles of operation, the conceptual design and the development of an expert system for fault diagnosis and monitoring of gas turbine combustion chambers are presented. The concept of the gas turbine chamber expert system is based on the monitoring of the spatial and temporal distribution of the heat flux inside the combu...

This paper describes the research actions put in place by the Directorate General of Research of the European Commission (EC) in the field of the mitigation of CO2 emissions. Global policy for climate change mitigation and the associated energy policy considerations are presented. The use of renewables and fossil fuels within the overall energy mix...

The use of mainframe gas turbines for power generation has increased in recent years and is likely to continue to increase. The proportion of power generation using combined heat and power is also growing mainly due to efficiency improvements and environmental benefits.Mini- and micro-turbines offer a number of potential advantages compared to othe...

This article presents the three objectives of European energy policy namely mastering global change and pollution, security of energy supply and creation of employment and the enhancement of the competitiveness of the European industry. An overview of power generation with gas turbine systems is given and the European Union strategy for supporting...

This article gives an overview of power generation with gas turbine and combined heat and power (CHP) systems. It also presents the European Union strategy for developing gas turbines and CHP systems. Ways to improve the performance of the several types of gas turbine cycle will be a major objective in the coming years. The targets are combined cyc...

As part of the process model, property models play a very important role in the design of separation by distillation. This paper provides a systematic analysis of the property models with special emphasis on relations between separation task, equilibrium properties and energy consumption. The presented analysis helps to establish the role of proper...

The 'Rational Use of Energy in Industry' sector of the 'JOULE' Programme focused on those new generic technologies which can bring major energy efficiency and pollution abatement, can compete with the best available technologies and can be transformed into commercial products or processes shortly after project completion. Some longer term technolog...

Important aspects related to modeling and simulation of reactive distillation processes are presented. Reactive distillation processes are system specific and are subject to the sensitivity of the model parameters. The sensitive model parameters have been identified as those belonging to the models describing the physical and/or chemical equilibriu...

One of the areas within JOULE is Rational Use of Energy in Industry which includes activities in CAPE (Computer Aided Process Engineering) for the energy intensive process industries. This paper describes a number of CAPE projects within JOULE, including energy synthesis, novel processes, exploratory studies and environmentally reinforced processes...

Various aspects related to simulation, design and operation of reactive distillation processes are presented through a systematic analysis of the model parameters and the important design/operational variables. The need for reliable, versatile and consistent simulation tools that allow the analysis of design/operation of reactive distillation proce...

A mathematical model has been developed to simulate the operation of an absorption-driven multiple-effect evaporator. The model is based on mass and enthalpy balances and heat transfer rate equations of the various components of the system. The model has been validated by comparing model predictions to experimental results from the operation of a f...

This paper discusses the role of the European Union through its Non-Nuclear Energy R&D Programmes, sector on 'Rational Use of Energy in Industry', in supporting energy efficiency in the paper industry. Projects, past and present, are described, several of which involve Finnish organisations. More generic technologies, for example heat exchangers, f...

This paper presents the European Union Research and Development (R&D) strategy in the field of rational use of energy in industry in the context of its Non-Nuclear Energy R&D Programs. The main subject areas cover heat recovery, unit operations, modeling of integrated processes and advanced sensors. Examples of projects in these areas are given. Th...

This paper presents the European Union R&D strategy in the field of rational use of energy in industry in the context of its JOULE R&D Programmes. The main subject areas are relevant to chemical engineering and cover heat recovery, unit operations, modelling of integrated processes and advanced sensors. Examples of projects in these areas are given...

Theoretical and experimental studies of absorption-driven multiple-effect evaporators were carried out. Theoretical predictions for such units were compared with existing industrial-scale conventional evaporators. It was calculated that the total energy consumption of an absorption-driven evaporator is considerably lower than that of a conventional...

Important European co-ordinated research activities in heat exchanges are within the European Community Non-Nuclear Energy R&D Programme entitled JOULE, while national governments and a wide variety of industrial laboratories and companies also carry out work in these areas.This paper will cover the past and present JOULE activities in a number of...

This paper presents information on research activities aimed at controlling the fouling behaviour of heat exchangers in industry. The research forms part of the JOULE Non-Nuclear Energy R&D programme of the European Community.

Since 1975 the Commission has been stimulating R & D work aimed at energy saving. The conference objective was to provide an international forum for the presentation and discussion of recent R & D relevant to energy efficiency, taking into account environmental aspects, in the energy intensive process industries.

This paper discusses the role heat exchanger R&D plays in industrial energy conservation, with examples drawn from the Commission's non-nuclear energy R&D programme. The direction that future strategic heat exchanger R&D should take is indicated.

A purpose-developed theoretical model was used to study the esterification of acetic acid by methanol in a reaction-distillation column. The effects of changing various operating parameters were predicted. The model showed that independent changes in several parameters should enhance the overall conversion. A further study indicated that by adding...

Industry is divided into many sectors, some of which can be highlighted as the most important energy consumers. A range of retrofit and process changes can lead to substantial reductions in energy used and, ofcreasing importance, improved competitiveness and pollution abatement.Possible actions for improving energy efficiency in industry are classi...

A calculation procedure was developed to simulate the mass and heat balance of a steam generation and distribution system of a large petrochemical site. Results of the procedure, which was implemented on a digital computer, were used for equipment design purposes, operation planning and efficiency monitoring. The available energy in steam was utili...

The main objectives of the Ccmnunity's energy policy consist of securing a sufficient energy supply for the present and future demand of its Member States and in reducing the Community's dependence on imported energy through the more rational use of energy and a broader diversifi­ cation of supply. This requires a full set of common efforts at all...

The vapor-liquid equilibrium behavior of the quaternary system methyl acetate-methanol-water-acetic acid was modeled by using the Margules equation in combination with Marek's method for the association of acetic acid. The constants in the Margules equation were obtained from existing or experimentally determined equilibrium composition of the cons...

Thesis (Ph. D.)--University of London, 1974.

The provision of fresh water is becoming an increasingly important issue in many areas in the world. Areas around the Mediterranean are between these in which demand for fresh water is expected to increase within the coming years. Greece and mainly Greek islands face water scarcity problems especially during summer period where the population incre...