Characterisation of supplementary fuels for co-combustion with pulverised coal

The current and future energy policy aims at increasing the share of renewable energy in worlds energy supply. One possibility to enhance energy production by renewable sources within a short term is co-combustion. This means co-firing biomass and waste with fossil fuels at existing power plants originally designed to fire fossil fuels. In...

Low NOx emissions from fuel-bound nitrogen in gas turbine combustors

Biomass-derived LCV (Low Calorific Value) gas represents one of the best alternatives for fossil fuels. It is very attractive, because it is CO2 neutral as biomass consumes an amount of CO2 when growing and releases almost the same amount when combusted. However, the raw gasifier producer gas contains a high content of fuel-bound nitrogen (FBN),...

Combustion and co-combustion of biomass in a bubbling fluidized bed boiler

This PhD dissertation concerns the study of different aspects of biomass (co)-combustion in small-scale fluidized bed boilers for heat generation. The most renowned gaseous emissions from fluidized bed combustion, namely, CO and NO, are investigated with the help of experimental and theoretical studies. In addition, dust and metal emissions in...

Steam boilers: Process models for improved operation and design

Biomass combustion can be an economic way to contribute to the reduction of CO2 emissions, which are a main suspect of the so-called greenhouse effect. In order to promote a widespread utilization of biomass combustion, operational problems like fuel treatment, slagging, fouling and corrosion have to be solved. There are few research initiatives...

The Delta dryer: Theoretical and technological development of an energy-efficient dryer for sludge

The annual production of watery waste streams is significant. Considerable fractions are contaminated and cannot simply be disposed off. They must be stored or further treated. The latter option usually involves a thermal drying step, which renders the residue suitable as a resource: 1. Sludge with high organic content can serve as biofuel. 2....

Characterisation and prediction of deposits in biomass co-combustion

This PhD thesis deals with the theoretical, experimental and modeling work which was performed to study deposition during biomass and waste co-combustion in pulverised coal facilities. Fossil fuels dominate the current energy scenario. Increasing concerns about fossil fuels availability and about the impact of their extensive use on the...

The Chemistry and Technology of Furfural Production in Modern Lignocellulose-Feedstock Biorefineries

This dissertation deals with biorefinery technology development, i.e. with the development of sustainable industrial methods aimed at the production of chemicals, fuels, heat and power from lignocellulosic biomass. This work is particularly focused on the production of furfural from hemicellulose-derived pentoses. The possibility of producing...

On the gasification of biomass in a steam-oxygen blown CFB gasifier with the focus on gas quality upgrading: Technology background, experiments and mathematical modeling

This work presents and discusses the results of the research on the gasification of biomass in an atmospheric circulating fluidized bed, with a mixture of steam and oxygen as fluidization / gasification medium. The main objectives of this research were to investigate and improve the gasification process in order to produce hydrogen-rich gas from...

A large-scale biomass bulk terminal

This research explores the possibility of a large-scale bulk terminal in West Europe dedicated to handle solid and liquid biomass materials. Various issues regarding the conceptual design of such a terminal have been investigated and demonstrated in this research: the potential biomass materials that will be the major international trade flows...

Torrefaction of herbaceous biomass: A study of product, process and technology

Co-firing biomass with coal in pulverized fuel boilers is a readily implementable means for attaining renewable electricity generation targets. Even as utilities have gained considerable operational experience over the past years with co-firing small quantities (0-3% on energy basis) of assorted biomass and waste residues for power production,...

Supercritical Water Gasification of Wet Biomass: Modeling and Experiments

In the following decades, biomass will play an important role among the other renewable energy sources globally as it is already the fourth largest energy resource after coal, oil and natural gas. It is possible to obtain gaseous, liquid or solid biofuels from biomass via thermochemical or biochemical conversion routes. Among them, gasification...

Fly ash from coal and biomass for use in concrete: Origin, properties and performance

Coal fly ash is widely used in as raw material in concrete industry because it can replace part of the cement and fly ash contributes to improve certain properties of concrete. As a way to reduce the contribution of coal fired power plants to the climate change, more and more coal is replaced by biomass. To keep fly ash as a valuable resource...