The EU Biofficiency project (2016-2019): executive summary

The EU funded project Biofficiency developed some tests on pre-treated fuels and a blueprint for the modern biomass cogeneration plants. We summarize the key conclusions which relate to fuel ash.

  • Additives and materials
    • Deposits tests in PF boilers to reduce deposition showed that the additive amount has a greater important than the type of additive. In particular, within the 4 MW CFB tests, elemental S was found to be the most cost-effective additive (with respect to kaolin). 200 kW tests showed that in PF beech wood combustion with 1% kaolin decreased PM1 emissions by 33%; by 75% with 2.4% kaolin.
    • 800 MWth CHP Avendore U2 and Studstrup U3 tests showed that coal fly ash addition decreased the submicron aerosol particles, but kept the K-Ca-S sintered downstream deposits (sootblowing was maintained). SH Cl corrosion on TP347H/HFG, SUPER 304H, Esshete 1250 was mitigated with 2,5% coal fly ash addition, but corrosion by sulphidation was observed.
    • With lab tests to test high steam temperature, at 650°C, only the austenitic SS TP310HCbN survived to heavy KCl corrosion.
  • Pre-treatments
    • Torrefaction increased the ash content without causing compositional changes, but if followed by a washing step it decreased alkali and Cl content, consequently increasing ash melting temperatures.
    • Steam explosion did not induce significant ash compositional changes, a slightly decreased ash melting temperature was found.
    • Hydrothermal carbonization decreased alkali and Cl content, yielded high Si-ashes and higher melting temperatures.
    • Detailed fuel and ash data are now publicly available and those could be used in our numerical modelling.
  • State of the art PF power plant design expected at 2.7 k€/kWel: 300 MWth, 560°C steam temperature and 92-94% efficiency, fuelled by wood pellets, dry de-ashing with ash recirculation, additivation with coal fly ash for SH and Denox SCR reactor protection including ash utilization oriented plant operation.

Effects of air preheating and FGR on PM release and NOx emissions: 2020-21 updates

Recent works on that topic, checked for a Customer, include:

Archan, G., Anca-Couce, A., Buchmayr, M., Hochenauer, C., Gruber, J., Scharler, R., 2021. Experimental evaluation of primary measures for NOX and dust emission reduction in a novel 200 kW multi-fuel biomass boiler. Renewable Energy 170, 1186–1196.

Meng, X., Ismail, T.M., Zhou, W., Yan, Y., Ren, X., Sun, R., Abd El-Salam, M., 2021. Numerical study of preheating primary air on pinewood and corn straw co-combustion in a fixed bed using Eulerian-Eulerian approach. Fuel 289, 119455.

Meng, X., Zhou, W., Yan, Y., Ren, X., Ismail, T.M., Sun, R., 2020a. Effects of preheating primary air and fuel size on the combustion characteristics of blended pinewood and corn straw in a fixed bed. Energy 210, 118481.

Pérez-Orozco, R., Patiño, D., Porteiro, J., Larrañaga, A., 2020a. Flue Gas Recirculation during Biomass Combustion: Implications on PM Release. Energy Fuels 34, 11112–11122.

Pérez-Orozco, R., Patiño, D., Porteiro, J., Rico, J.J., 2020b. The effect of primary measures for controlling biomass bed temperature on PM emission through analysis of the generated residues. Fuel 280, 118702.

Raheem, D.G., Yilmaz, B., Kayahan, U., Özdoğan, S., 2020. Effect of Recycled Flue Gas Ratio on Combustion Characteristics of Lignite Oxy-Combustion in a Circulating Fluidized Bed. Energy Fuels 34, 14786–14795.


BIOFACT Engineering joins the event: “Bringing VALUE to AGROBIOMASS”

We joined the event: “Bringing VALUE to AGROBIOMASS” organized by the AgroBioHeat project to facilitate cooperation on sustainable utilisation of biomass from agriculture and side streams from food production.

All over Europe, there is agricultural production of various crops for food and feed and processing of these crops. This results in a large volume of residual biomass streams that can be utilised for various purposes; however, their current mobilization rates remain generally quite low. These resources have the potential to contribute to the transition from a fossil-based economy to a green economy. Agriculture can also provide additional biomass resources through improved land management practices, e.g. by cultivating new crops on marginal lands. Whatever their origin, these agrobiomass resources can be used for production of energy, chemicals, new food products, pharma, materials, and more. The challenge to realise this potential is in some cases a technological one, that requires innovation and development of new processes and equipment. In many cases, e.g. the use of agrobiomass for heat production, there are already available mature technologies in the market that are ready to go, but their market uptake is hindered by absent value chains and lack of knowledge about available technologies. The Bringing Value to Agrobiomass event addressed this by providing an online matchmaking platform for participants to display their technology, express their technological or material needs, or bring attention to their excess biomass resources in order to find cooperation partners to help utilise them. The ultimate goal was to connect relevant stakeholders to facilitate new collaboration on improved use of all these resources.

Corrosion Atlas Case Studies – focusing on ash fireside effects

Beside slagging and fouling, our approach at BIOFACT engineering is to predict quantitatively the critical gas and/or phases in the flue gas streams, to assess the corrosivity level of the specific fuel (mixture) in the energy plant, depending on operating conditions. Specific cooling models are applied to assess condensation on metal surfaces and corrosivity of deposits formed.

Need a deep dive into corrosion? We recommend the Corrosion Atlas Case Studies.

Your Digital Fuel Specialist – in your glasses #2021

Have you ever thought you could have a BIOFACT digital fuel specialist always at your service?

With today’s tool we could make possible to have a online concurrent site investigation, in real-time, with glasses which can connect us with you in an instant, bringing expertise to right where you are.

We could “see what you see” through a live video stream so to provide instant expertise and evaluation on plant operation, with a focus on ash behaviour assessment (slagging, fouling, corrosion), for example during a predicted maintenance or a sudden stop of operations.

Contact us for further details!

Smaller scale RDF/SRF plants – alternative horizontal boiler design for sticky RDF ash

Smaller WtE plants, integrated at different levels of the urban environment, minimise the transportation of waste and ensure the local benefit is maximised from community waste.

In a recent project, a manufacturer developed a rotating boiler with automated cleaning to reduce ash build up on surfaces, specifically for high ash RDF/SRF. The system was designed from 2017 and grated the patented in 2019.

Instead of using an adiabatic furnace linked to a single pass radiant coil and with convective heat batteries equipped with steam/air cleaning nozzles, a standard vertical boiler design is placed horizontally to be able to rotate. This also allows to reduce installations height (reduced construction costs). Continuous rotation more easily removes ash and guarantees performance up to 30% ash fuels. Granular recyclable cleaning media can be used where required (no cleaning systems). Fuel feed, grate speed and combustion air is optimized with a computer vision control system.

Download the boiler design patent

Is this rotary incinerator design more reliable than the most often use, dynamic water-cooled moving grate? It depends on the system size and fuel spectrum. We will wait for additional return on experience from new plants and keep you updated!

Webinar Series – Agricultural Residues

Date: 9 December 2020 Time: 1100 – 1300 hrs

Agriculture residues are one of the most abundantly available resource worldwide as millions of tons of husk, straw etc. are produced globally which are either left to rot or burned on the fields. Efficient utilization of these residues to produce heat, electricity and biofuels offer various advantages including replacing fossil fuel use, reducing emissions, and promoting local economic development. However, various technological, social and policy challenges hinder the progress of the sector.

In this regard, World Bioenergy Association is pleased to invite everyone to an upcoming free webinar which will focus on the latest combustion technologies available in currently operational commercial facilities worldwide. The session will include presentations from industry representatives who will inform on the latest state of art in technology development for efficient agricultural residues to energy conversion.

Register here

The webinar will include

  • Opening remarks from World Bioenergy Association
  • Presentations from equipment manufacturers about the latest technological developments in the agriculture residues to energy sector
  • Panel discussion and sharing of best practices to promote the sector
  • Live Q&A with audience

This webinar is the 1st in a series of webinars to focus on agricultural residues to energy sector with subsequent webinars planned to focus on research, supply chain logistics and end uses.