Objectives

S&T Objective 1: To select optimal energy crop species suitable for both biomass production and phytoremediation purposes of HMC sites

Miscanthus
(Miscanthus x giganteus)

Switchgrass
(Panicum virgatum)

Virginia Mallow
(Sida hermaphrodita)

Cordgrass
(Spartina pectinata)

There are several energy crop species which IETU has been testing for several years on heavy metal contaminated (HMC) arable land to investigate their capacity for biomass production in combination with phytoremediation effects, especially phytoextraction. In order to select optimal species plot experiments and a testing campaign on real HCM sites will be designed and executed by IETU (academia) and VITA34 (industry) using energy species selected from the already tested ones and phytoremediation knowledge of IETU (academia) in combination with HMC sites management practices and remediation operations engineering of VITA34 (industry). The tests will be carried at existing test plots provided by IETU and new experimental plots to be set up at sites provided by IETU in Poland as well as by VITA34 (industry) in Germany. Biomass from existing plantations will enable preliminary biomass validation as biofuel feedstock, analysis and assessment of end-products after gasification (under S&T O3) as well as provide material for microbiological investigations and trials for microbial stimulation (inocula) and its optimization on biomass yield and composition already at the initial project phase. In project year 2, 3 and 4, the tests will be performed using biomass from the newly established plots. In total it is planned to carry out the tests for three vegetation seasons. The tests will allow to determine which of the preselected species to demonstrate which deliver the best yield under HM contamination, in relation to S&T O2, what are the effects of the standard fertilization and inocula on the biomass composition as fuel feedstock (in relation to S&T O3) as well as assess the appropriate balance between biomass yield and remediation effects with respect to the HMC management focus. Guidance for selection and application of energy crops species for a phytoremediation driven production will be developed together with a cost effectiveness and environmental benefits analysis. The study will deliver information which energy crop species are optimal in terms of biomass yield, robustness and relative site management goals to help transfer the Phyto2Energy concept to HMC sites management practice.

S&T Objective 2: To develop a microbiological method stimulating the biomass yield at HMC sites

Microorganisms may significantly influence bioaccumulation/mobilization/immobilization of heavy metals in contaminated soil. More than in soils with high soil quality, the interactions between plant and microbes play a crucial role at sites where plant growth is affected by contaminants like heavy metals. This objective aims at identification of plant growth promoting rhizobacteria, bacterial endophytes and mycorhizal fungi, that enhance the growth of the selected energy plants species and to investigate the beneficial partnership between plants and their associated microbiomes as a strategy to accelerate plant biomass production and clean-up of the contaminated areas. To achieve this objective already existing inocula and formulations (Mother Cultures SCD ProBio Plus provided by ProBiotics) will be used including bacteria-producing biosurfactants as a starting point to work out with IETU (academia) the possibility to reduce the pressure of phytopathogens. In addition new plant growth promoting bacteria will be isolated from the rhizosphere of the respective plant species to obtain new strains and to design new and more targeted formulations for enhancing plant growth pytopathogens. Moreover, the functional diversity of the rhizosphere microflora and bacterial endophytes will be studied to define strategies to enhance the abundance and activity of plant beneficial microbes in situ (HMGU). Finally mycorrhizal strains will be selected with improved tolerance for HMs to micropropagate the plants before planting into the contaminated soils. A robust indicator system will be developed to measure the success of the remediation process in situ. The indicator system shall be based on the abundance of bacterial resistance genes against HM, which are mostly located on plasmids and other mobile genetic elements and which increase or decrease very fast in response to the presence or absence of HM stress. This system will also help ProBiotics to optimize the composition of the inocula. Finally the indicator system will provide clear data on the success of the phytoremediation effect on soil quality, and eventually lead to establishing and sustainable growth of the energy crops (enhance nutrition, seedling emergence and provide yield benefits) in relation to achieving the S&T O3.The system will be tested at the experimental plots at real sites established under S&TO1 in Poland and in Germany. The works will involve extensive knowledge of biosurfactants and products commercially offered by ProBiotics (industry) as a basis for innovations and optimisation in industrial biotechnology with expertise on fungi pathogens offered by IETU (academia) and on environmental factors and individual genetic disposition offered by HMGU. As a result a composition of a novel inocula will be proposed to stimulate the phytoremediation driven energy crops production respectively to the relative brownfields management goal (i.e. either stimulate the biomass growth or the metal uptake) together with a set of indicators enabling monitoring the success of energy crops cultivation and a phytoremediation effect. They will be tested and optimized on the experimental plots in Poland and in Germany.

S&T Objective 3 Valorize the biomass from the HMC as a local energy carrier

SUT Laboratory of High
Temperature Processes

Activities under this objective aim at defining a set of control parameters relevant for biomass from HMC sites in order to utilise it in an environmentally safe way as fuel feedstock. A plan for its conversion into energy in a small scale local installation will be investigated with special focus on gasification as a promising innovative alternative for a HMC contaminated biofuel. There are a number of technologies for contaminated biomass utilization; however gasification has this beneficial feature that it enables on site conversion of the biofuel into both electricity and heat minimizing the transport costs. Biomass gasification consists in its thermal conversion into a product gas composed primarily of CO, H2, methane and light hydrocarbons in association with CO2, H2O and N2, depending on the specific gasification process. Moreover, the gasification process has many other advantages compared to other thermal methods as it takes place in small amount of oxidizer and leads to a multi-use high-quality flammable gas that can be combusted for the generation of electricity or support such processes as drying or co-combustion in boilers to reduce NOX emission. In particular small scale installations represent a considerable potential for market penetration especially in Central and Eastern Europe which on one hand are areas of rich biomass resources and on the other have many HM contaminated postindustrial sites which require efficient management. ISPE (industry) in cooperation with SUT (academia) will work out a list of parameters to valorize the biomass from HMC sites as biofuel from the viewpoint of the characteristics of the equipment and technical options of potential installations as well as environmental aspects with stress on small scale gasification installations. To valorize the biomass, ISPE (industry) and SUT (academia) will carry out gasification tests of the biofuel obtained from the control as well as newly established plot experiments in Poland and in Germany using a small scale fixed bed downdraft gasifier installation provided by SUT. The impact of the biofuel feedstock parameters on the quality and composition of the end gas and end products from gasification will be evaluated and analyzed according to the list of the elaborated parameters. The gasification tests and the biofuel /end-products analyses will allow to understand which char/ash fractions are formed, how heavy metals behave during this process and if and which mineral components may affect the gasification process. They will also allow monitoring the process. This knowledge becomes crucial regarding the stimulation methods for the biomass growth and metal uptake (S&TO2), optimization of process parameters in relation to the subsequent handling of the produced ash fractions especially in view of their application for soil improvement purposes. The guidance on the improvement of the process parameters worked out by SUT and ISPE will aim at concentrating most of the heavy metals char/ash samples. IETU and ISPE will then assess the applicability of the ash (and char) for land applications as mineral fertilizer in remediation process.