Phosphorus Google 41116Plants need phosphorus to grow and of a kind that they can assimilate. Photo by courtesy of Google Images (4 November).Thanks to new grants from the Swedish Research Council, three new projects can go ahead in Bio4Energy aimed at developing cost-efficient and clean technologies for biogas or synthesis gas scrubbing, which can serve as alternatives to similar technologies based on the use non-renewable fossil fuels. In addition, Bio4Energy's flagship project on phosphorus recovery and removal of contaminants from waste sludge can be taken a step further towards implementation of the technology on a commercial scale.

Funding from the Council, known by its acronym VR, generally aims to support frontline fundamental research that brings new knowledge to the research community. Receiving a grant from VR is considered as being something highly prestigious. The four projects will be run by PIs on the platforms Bio4Energy Chemical Catalysis and Separation Technologies (Mattias Grahn and Jyri-Pekka Mikkola, respectively), Bio4Energy Thermochemical Conversion Technologies (Marcus Öhman) and Bio4Energy System Analysis and Bioeconomy (Xiaoyan Ji):

  • Understanding and optimising mass transfer in small-pore zeolite membranes

  • Formation of plant-available phosphates in thermochemical conversion of biomass and waste streams

  • Multi-scale modelling of interfacial properties for CO2 separation with deep eutectic ionic liquid-based solvents

  • Hydrated ionic liquids: From chemical energy storage and CO2-based chemicals to processing of bio macro molecules

Below is an account of the two first projects in the list.

'Understanding and optimising mass transfer in small-pore zeolite membranes'

Bio4Energy's researchers developing zeolite membranes for gas and liquid separations have so far developed and perfected ultrathin MFI zeolite membranes and brought them to scale for pre-industrial applications. MFI is short for Mobil FIve to remind of the company Mobil Oil which first syntesised such membranes. Meanwhile, the Bio4Energy researchers' headline process draws on MFI zeolite membrane technology for the separation of carbon dioxide (CO2) from methane-based biogas intended for use as car fuel.

In the project just granted, however, they propose to use an alternative zeolite material called Chabazite which has smaller pores and somewhat different properties compared with the MFI ones. The idea is to make a membrane construction completely void of aluminium and contaminants in the feed, which would not only make the material more environmentally friendly but likely also insensitive to water, as well as more reliable in terms of performance.

"Our membranes are already thinner and have better flux [than similar ones on the market]. If we can use Chabazite, which is even better [than MFI] at separating CO2 from CH4, the likelihood is that we will achieve a very efficient process for the separation of CO2 from natural gas or synthesis gas", according to project leader Grahn, who is a professor at the Luleå University of Technology (LTU).

Grahn cautioned however that there is a great need for developing knowledge that will allow the researchers to perfect the technology, which is just what the four-year VR project is designed to do. Further steps then will have to be taken to implement the technology first at a demonstration and then an industrial scale. 

"By the end of the project we will have a model that can be used to optimise a membrane process for the separation of CO2 from biogas", he said.

Project partners on the Bio4Energy Chemical Catalysis and Separation Platform are This email address is being protected from spambots. You need JavaScript enabled to view it. and Jonas Hedlund, both researchers at LTU.

'Formation of plant-available phosphates in thermochemical conversion of biomass and waste streams'

The VR grant contributes to funding a body of work that—if supported through the stages from laboratory invention to commercialisation—may start to make a real difference for sustainable global food and feed production a decade from now.

It is the result of over a decade worth of preparatory work aimed at finding an efficient and environmentally acceptable way of recovering phosphorus from municipal waste sludge and industrial waste sludge from forestry by researchers on the platforms Bio4Energy Thermochemical Conversion Technologies and Bio4Energy Environment and Nutrient Recycling. At this advanced stage of the research process they have teamed up with a possible future technology owner—one of the largest in the business, Andritz—and municipal actors in Sweden in charge of current bioenergy facilities which could be adapted for the new type of co-firing operations proposed.

Phosphorus is an essential ingredient in fertilizer used in agriculture and forestry to spur plant growth. The main route of extraction is from rock by mining in a handful of countries worldwide. The phosphorus thus extractable (or phosphate, which is the base substance) is a finite resource that is expected to run out in 50-to-a-few-hundred years' time. Ideally, therefore, the phosphorus that enters our food and feed via plant uptake should be recycled and re-used.

The Bio4Energy scientists believe this can be done by combusting sludge and biomass together in bioenergy operations. The former are perfecting a method and technology for this in a project previously supported by the Swedish funding organisations BioInnovation, the Swedish Research Council Formas and Bio4Energy. The freshly obtained VR grant will serve to perfect the technology used in the thermal conversion of the sludge and biomass by so-called co-firing.

According to researcher leader Öhman, professor at the Luleå University of Technology, this is a crucial step in the process. There are already a number of methods being proposed around the world for phosphorus recycling, but none have been fully commercialised. Apart from being cost efficient, the method which is finally chosen should be sufficiently good at separating out and removing pathogens and toxic heavy metals present in the sludge used as feedstock and, last but not least, the phosphorus coming out of the resulting technology process should be of a kind that plants can easily assimilate. 

"We are going to perform detailed studies of the way phosphorus is formed and analyse its structure to shed light on its phase composition and reaction paths. We are also going to analyse in depth the phosphate present in the ash [directly after co-firing]", according to Öhman.

"If funding is forthcoming and ongoing research results look promising… we could have full-scale facilities for demonstration of the technology [up and running] within five years", he said;

"If our results are promising we will have a commercial partner that is interested [in bringing the technology to the market]. In ten years' time it could be commercialised on a global scale".

Project partners
Bio4Energy Thermochemical Conversion Technologies: This email address is being protected from spambots. You need JavaScript enabled to view it. and Nils Skoglund, Umeå University
Bio4Energy Environment and Nutrient Recycling: Dan Boström, Umeå University
Anders Lagerkvist, Luleå University of Technology


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