Operating energy wood: Dalkia case study
Doing the business of operating heating
Energy units management and energy saleAfter having carried on at the research centre of Veolia (VERI), Mr Thibault Yon is now involved in the structuring of the supply chain of biomass at the Technical and Big Projects Department of Dalkia. He has agreed to share with us his occupation as a heating operator. Thibault Yon states “Dalkia purchases biomass to valorise it into energy and to sale it under the form of heat and/or electricity. Dalkia core business remains the management of energy units as well as energy sale. We sometimes build heating installations and supply part of the fuel, or all the fuel in most cases”.
Economy, ecology and techniqueAbout the criterions clients use to select a tender, Mr Yon goes on: “The selection of a project relies on many criterions but a balanced economic equation remains critical. The selection is supported and argued by technique; and political also plays a key part. For instance, the decision to use green energy (lay out of a new wood boiler room or transition from a fossil energy boiler into a biomass boiler) can represent a significant investment in a first approach, but plays its part in reaching the European and French objective of 23% renewable energies in the energy mix in 2020. Biomass will play a paramount part, especially thanks to the use of forestry wood. As far as France is concerned, it’s to be noted there are many forestry resources and they are managed and monitored.
As far as supply is concerned, biomass sustainability is a critical point.”
Optimising the valorisation of biomass
Timber and wood energyIn this context of significant development, it’s key to optimise the valorisation of the available biomass. But it is not so simple. “Timber and industry wood are the main products of the forestry industry and this is to go on. In valorising their opportunities it will be possible to valorise also more energy wood. Wood valorised as energy comes from the other exploitation products: small pieces of wood, logs the industries stated above are not interested in, wood from forest maintenance cuttings, etc. Theses biomasses are very heterogeneous compared to the chipped wood for the paper industry.”
Striving for optimum energy efficiency“Supply contracts specify the size of wood chips with minimum and maximum moisture content. If there is always a reference to the EN 14961 norm, it’s not always easy to comply with it in industrial operating conditions. This situation is changing progressively. Moisture measurement is of great importance all along the chain, from the forest to the entry of the boiler. Indeed, it is significant to pay for a biomass at a given and precise calorific value. The Humitest can be a solution as it’s a tool that gives quick moisture measurement, at platforms especially but also in the forest. The all thing is to know how to use it properly. Even though a person is within the right conditions of use, the measurements for heterogeneous biomass mixes won’t be optimal and also if the instrument is not properly used (volume, weight, setting). Indeed, this moisture meter is not calibrated for theses biomasses that change within time. With the Humitest, we are making tests to see if it’s possible to free from the type of biomass and make precise enough measurements. This thought is under way. The sampling is also a point to be careful about to make sure the samples are representative.”
Dalkia testimonial illustrates how important the representativeness of the sample is as well as the carefulness of the measuring with the l’Humitest for biomass.
Contributing to increase the quantity of energy produced from a same resource, the precise measurement of moisture content of energy wood plays its part in the limitation of the environmental impact of the energy produced.
With its hammer probe or special probes, this moisture meter allows to measure water content of round wood, split logs, wood chips, sawdust, pellets, hay, straw and cellulose bales.
This biomass moisture meter allows to measure water content and temperature of wood chips, barks, plant pellets, wood shavings, sawdust, miscanthus or corn cob.
"To check the water content of pellets"
"pricing depends on the measured moisture content"
Equilibrium humidity content
Also known as the hygroscopic equilibrium, this term is used to define the water equilibrium of a material in relation to external conditions.
NF444 - NF Solid biofuels
NF444 - NF Solid biofuels – Biofuels-pellets certifies the following characteristics:
- inferior calorific value (ICV) and moisture content,
- level of fines,
- level of ash,
- mechanical resistance,
- apparent bulk density,
- sulphur, chlorine and nitrogen levels.
This certification is based on the European norm EN 14961-2.