Introduction

The main objective of GrateCFD is development of CFD aided design tools and operational guidelines for optimum grate fired BtE and WtE plant operation through:

Model development: improved fuel/fuel bed and gas release models, heat-exchanger deposition models and reduced kinetics models (NOx); and validation of these

Simulations: transient and steady state CFD simulations of BtE and WtE plants; and validation

Concept improvements: BtE and WtE plant case studies selection, setup, simulations and analysis, giving design and operational guidelines

The sub-objectives are:

• Develop improved fuel, gas and particle sub-models to be included in the CFD simulations

• Develop numerical tools that are tailored to study concept improvements for grate fired BtE and WtE plants, with focus on emission reduction, combustion performance, energy efficiency and availability

• Obtain operational and retrofitting guidelines for optimum operation of grate fired BtE and WtE plants through CFD simulation case studies

• Education of highly skilled candidates within this area and training of industry partners

• Monitoring of activities and state-of-the-art within this area and dissemination of knowledge to the industry partners, and other interested parties when applicable

Main anticipated results of the project are guidelines that will be aimed at improving combustion conditions, obtaining optimum operation over a wide range of thermal loads, decreasing emission levels at significant variations in fuel composition and production demand and increasing combustion and plant efficiency and availability.

The Work Breakdown Structure of GrateCFD is:

GrateCFD management and work break down structure and project links and information flow. (WoodCFD: Clean and efficient wood stoves through improved batch combustion models and CFD modelling approaches, http://www.sintef.no/woodcfd; CenBio: The Norwegian Bioenergy Innovation Centre, http://www.cenbio.no; WtE 2030: KPN project application to RCN)

GrateCFD will run for four years (2017-2020) and has a total cash budget of 24 million NOK, which is 80% financed by the Research Council of Norway through the ENERGIX program and 20% financed by the industrial partners.

---

The GrateCFD consortium

The project consortium covers all the necessary aspects, and includes large and central industrial players in the biomass to energy (BtE) and waste to energy (WtE) areas in Norway, Sweden and Switzerland.

SINTEF Energy Research will lead the project and will focus on both modelling and experimental activities. NTNU (Norwegian University of Science and Technology) will supervise the PhD, the PostDoc and Master candidates, and lead specific modelling activities.

The industrial partners will contribute with finances as well as access to plants and their extensive industrial knowledge generated through their commercial activities within the BtE and WtE areas: Statkraft Varme AS, Oslo EGE, Returkraft AS, Vattenfall AB, Hitachi Zosen Inova AG.

The constellation of project partners is very strong, bringing together leading research organisations within the field and major industrial players.

---

Project background

Biomass to energy (BtE) and waste to energy (WtE) plants in Norway need to comply with stricter emission limits and/or adjust to tighter profit margins, and EU have implemented a further reduction of emission limits from medium (scale) combustion plants. Tighter profit margins mean that poorer/cheaper fuel qualities become interesting, as well as operational optimization with respect to efficiency and capacity maximization. NOx, particulate and CO emissions are special concerns, as well as the operational challenges following particle deposition on heat transfer surfaces. The majority of the operational BtE and WtE plants in Norway are grate fired plants, and even though different grate technologies have been developed, they suffer from both variations in fuel quality and changing operating conditions, resulting in non-optimum operating conditions. The most cost-effective measure to abate the resulting operational challenges, including increased emission levels, are with primary measures.

Computational Fluid Dynamics (CFD) is the ultimate design tool for BtE and WtE plant combustion and heat transfer sections, however, cost-effective sub-models need to be developed, implemented and used in an optimum way. Moreover, the CFD simulations need to be carried out for transient conditions, to study the effect of changing operating conditions, and minimize the impact of these through improved plant operation and operational guidelines.

The proposed project therefore focuses on enabling optimum grate fired BtE and WtE plant operation through CFD aided design and operational guidelines. Improved models and modelling approaches, in combination with targeted experiments/measurement campaigns, are keys for future's increased sustainable BtE and WtE plants. This will have a significant impact on two of the most important renewable value chains in Norway today, the BtE and WtE value chains.

---

Project overview

The project is divided into 5 subprojects (SP), each subproject is itself divided into several work packages (WP).
 
• Fundamental modelling & model development - SP1
• CFD tool development - SP2
• BtE and WtE plant concept improvements - SP3
• Education and training - SP4
• Technology monitoring and dissemination - SP5
 
Fundamental modelling & model development - SP1

The main objective of SP1 is to develop improved fuel, gas and particle sub-models to be included in the CFD simulations in SP2 and SP3.
 
CFD tool development - SP2

The major objectives of SP2 are to develop a numerical tool that is tailored to study concept improvements for grate fired BtE and WtE plants, with focus on emission reduction, combustion performance, energy efficiency and availability.
 
BtE and WtE plant concept improvements - SP3

The major objective of SP3 is to obtain operational and retrofitting guidelines of grate fired BtE and WtE plants through CFD simulation case studies.
 
Education and training - SP4

The major objective of SP4 is to strengthen the education within this field through MSc and PhD students, and a PostDoc candidate. The objective is also to increase the competence level in the industry. The long-term goal is competence building and strengthening of the education within combustion of biomass and biomass residues in BtE plants and MSW in WtE plants.
 
Technology monitoring and dissemination - SP5

The major objectives of SP5 are to monitor the latest research and technological developments and to disseminate research results.

---

GrateCFD deliverables

In the first year of GrateCFD, focus will be on theoretical studies, model development and preparation for experimental activities that will form the foundation for the succeeding studies to be carried out.

---

GrateCFD kick-off in Trondheim

The GrateCFD official kick-off took place at a combined kick-off and steering committee meeting in Trondheim on 29 June, where all the partners were present. This successful meeting was the first in a series of meetings and workshops to be arranged throughout the 4-year project period.

Participants at the GrateCFD kick-off meeting

---

PhD position announced

The PhD position within "Computational fluid dynamics (CFD) modeling of biomass and waste to energy plants" has been announced. A number of applications have been received, and the employment process is ongoing.

---

 

New publications

Inge Haberle, Øyvind Skreiberg, Joanna Lazar, Nils Erland L. Haugen (2017). Numerical models for thermochemical degradation of thermally thick woody biomass, and their application in domestic wood heating appliances and grate furnaces. Progress in Energy and Combustion Science 63(November 2017):204-252. 

Øyvind Skreiberg (2017). Computational Fluid Dynamics for improving micro- to large-scale woody biomass and municipal solid waste combustion units. EERA Bioenergy News 2017 (7), p. 5.

Øyvind Skreiberg (2017). Modellering og numeriske simuleringer for økt bærekraft (in Norwegian). SINTEF blog article.

---

Other news

IEA Task 32 Biomass Combustion and Co-firing

An IEA Bioenergy Task 32 meeting was arranged in connection with the 25th European Biomass Conference and Exhibition in Stockholm, Sweden, 12-15 June 2017. For information about IEA Bioenergy Task 32 activities, see newsletters, and for IEA Bioenergy news, see newsletters.

Øyvind Skreiberg from SINTEF Energy Research is the Norwegian participant in IEA Bioenergy Task 32.

EERA Bioenergy – SP5 Stationary Bioenergy

The effort this year has been focused on revising the SP focus and the description of work. For more info on EERA Bioenergy, visit the website, and see the newsletters.

Berta Matas Güell from SINTEF Energy Research is leading SP5 Stationary Bioenergy in EERA Bioenergy.

RHC technology platform

The activity level of the RHC platform has picked up, after a period where new financing solutions were sought and the originally planned strategy documents had been delivered. The "new" European Technology and Innovation Platform on Renewable Heating & Cooling (RHC-ETIP) brings together stakeholders from the biomass, geothermal and solar thermal sector - including related industries such as District Heating and Cooling, Thermal Energy Storage, Hybrid Systems and Heat Pumps - to define a common Research, Development and Innovation strategy for increasing the use of renewable energy technologies for heating and cooling.

Previously concrete work has been carried out by the Biomass Panel in the RHC-ETIP connected to giving input to the SET-plan issues paper on renewable fuels and bioenergy, as well as work connected to the Implementation of the biomass technology roadmap of the Biomass Panel. The aim of the latter was to update the progress in R&I priorities identified by the Biomass technology roadmap.

This work continues through different efforts, whereof a Biomass Panel steering committee meeting was arranged 20 June in Brussels. Øyvind Skreiberg from SINTEF Energy Research is a member of the Biomass Panel Steering Committee and the leader of Issue group 2: Residential/small scale heating devices and building integration.

See the RHC newsletters for other news.

---

Contact:

Øyvind Skreiberg - oyvind.skreiberg@sintef.no

Project website:

www.sintef.no/GrateCFD

The project website will contain both partner information and relevant links.