As a focus on the development of particle transport projects through the pipeline, a new type of carbonized particles are molded, which increases the volume energy density, durability and moisture resistance.
The initial idea for the Queen's University project in Kingston, Canada, was to develop a wood pellet that meets the desired characteristics of pipe transportation Andrew Pollard, Professor of Mechanical and Materials Engineering, Queen's University, Kingston To do this, The requirements are spherical to maximize filler in the pipe. The particles also need to be highly durable and withstand the impact and wear of pipes and other particles. Of course, they must be able to be submerged in the pipe for a long period of time - At that time, such a particle did not exist at all, so the Queen's team started a research project on its own.
The carbonization process is interesting because the particles made using this process not only increase the energy density but also improve the hardness, most notably the hydrophobicity. However, the existing cylindrical carbonized particles are not optimal in the pipeline and the fracture The ends are easy to fill with water and produce fine or fine particles.To be transported by pipe, the particles will require a continuous, smooth and impervious outer surface to minimize damage and water ingress.
To do this, the team made the pellets by compressing the biomass between the two hemispherical molds instead of extruding the material through the mold like conventional pellets.Another variant of conventional processing involves compressing The mold is heated to the set temperature for a period of time, the biomass in the mold cavity is carbonized, and the granules are then pressed.
Interestingly, the team found that sample degassing creates an environment within the mold that prevents the air from interacting with the heated sample, thereby eliminating the need for an inert environment during carbonization.The first particle produced was dark brown in color with a carbonized Like particles, they have a smooth, hard and shiny outer surface and, unfortunately, they also have a fragile equatorial plane that easily divides into two halves.
As the other properties of the particle half overcome many of the weaknesses of the cylindrical particles, the team focused on the interaction of the particles within the mold during compression and determined that the weak equatorial plane was due to insufficient contact between the particles The need to improve the mix between the biomass fibers necessitated Pollard and the team to redesign the molds, which functioned like ice cream scoops.The resulting granules had the same watertight exterior surface and were also firmer, as modified Impact tests prove - for example, throwing particles onto a concrete floor; they bounce off and have no effect on the surface.
However, carbonizing the biomass in the molds made it difficult to scale the process to industrial capacity, so the team turned its attention to determining if the carbonization and granulation steps could be separated while still achieving the same robust particles.
To get help, the team invited David Strong, a professor at Queen's University and chair of design engineering at the Natural Science and Engineering Research Council, to evaluate that teams need to minimize the time spent on biomass in molds if they are to be used industrially , Meaning that either the biomass is loaded into the mold after it is preheated or the heating rate of the biomass within the mold is significantly increased.
The first challenge was to deal with material handling challenges, especially in a university laboratory environment, so the team focused on the second option. However, the traditional wisdom of that time was that the temperature in the carbonization process should not exceed 50 degrees Celsius and Once cooled, the carbonized material 'sets' and can not form solid particles, and the researchers question these assumptions and through a series of experiments show that previously heated and cooled biomass can be quickly reheated and compressed to form The same quality of solid particles obtained using the original process.
This is a key finding that enables teams to further develop, whether raw or pretreated biomass, to stay close to zero during the compression cycle.Many types of biomass have been successfully used in the process, covering Woody and non-woody biomass, such as poplars, switchgrass, oat hulls and cannabis.
Facts have proved that the properties developed by Queen's University (hereinafter referred to as Q'Pellets) are also well suited for more traditional applications such as co-firing with coal for power generation and as a substitute for low-carbon fuels in cement production. , Q'Pellets have a higher energy density, hardness and hydrophobicity than white or non-carbonized particles.
However, the compression molding process used for Q'Pellets results in an increase in density, the increase in bulk density due to its spherical and improved packing material, and hence an increase in volume energy density. Q'Pellets also have a continuous, smooth and water-impervious outer surface to a maximum Reduce the generation of dust and thus reduce the problem of dust explosions.In addition, their shellfish surfaces minimize water entry - interestingly, the team found that Q'Pellet was submerged in water for a year and a half and was durable Sex has no effect.
In order to assess the commercial potential of Q'Pellets, a spreadsheet-based model was developed to allow for techno-economic analysis and simplified life-cycle analysis of Q'Pellets, cylindrical carbonized particles and cylindrical white particles Based on the following hypothetical case study , A commercial-scale plant built at Lake Williams, British Columbia, completed product deliveries in Rotterdam, the Netherlands, comparing the production of each particle type based on its internal rate of return and lifetime GHG emissions.
The simulated internal rate of return for Q'Pellets was 12.7%, with 11.1% for white particles and 8% for carbon particles. A simplified life cycle analysis showed that Q'Pellets had the lowest GHG emissions during the life cycle of all three products, at 6.96 kgCO2eq / GJ, while white particles are 21.50kgCO2eq / GJ and carbonized particles are 10.08kgCO2eq / GJ. Over these life-cycle GHG emissions levels, white particles are above the maximum sustainable life-cycle emissions under the EU regulations. By modifying the input The sensitivity analysis of the model to the variables shows that the white particles are more sensitive to uncontrollable market variables, especially particle sales prices, biomass feedstock costs and transportation costs. A Monte Carlo analysis was also conducted and the results show that the white particles are more sensitive to Q'Pellet Production of white particles is less predictable than production and more likely to lead to negative IRR.
Q'Pellet has the obvious advantages of increased bulk energy density, superior performance and shorter greenhouse gas emissions cycles, however Q'Pellet technology is at a relatively early stage of development and more needs to be done to improve its skill levels. Pollard And Strong believe that by working with technology-based industrial partners, this can best be achieved by moving the technology forward.
As a result, the university's technology transfer office has been working to help identify industrial partners interested in developing and commercializing Q'Pellet technology, has a US patent covering the Q'Pellet mold design, and extensive processing technology and expertise, The team believes it has built a strong foundation to build a new proprietary granulation platform.
