Bioleaching by endophytic microorganisms as a method of element recovery from sewage sludge incineration ash 

<div>&#160;</div><div> <p><strong><span>Bioleaching by endophytic microorganisms as a method of element recovery from sewage sludge incineration ash</span></strong><span>&#160;</span></p> </div><div> <p><span>Incinerated sewage sludge ash (ISSA) has been proven to have resource potential, and in case of some elements, such as phosphorus, in the same concentration range as currently exploited ores. Usage of waste resources, such as ISSA, to recover valuable elements together with the efficient methods are main assumption for sustainable development. Alongside feasibility, economic, energetic and environmental cost of methods applied have to be taken into consideration.&#160;</span><span>&#160;</span></p> </div><div> <p><span>The effective alternative methods to chemical treatment to recover elements form ISSA that simultaneously lower the negative impact of chemical reagents are biological methods. Microorganisms based solutions, even though described, have still underexplored potential in the field of element recovery. One of the reasons for this state is a limited range of species of microorganisms used for this purpose up to date.&#160;</span><span>&#160;</span></p> </div><div> <p><span>In present study bacteria and fungi, capable of phosphorus and metal containing phase solubilization, were employed in bioleaching of ISSA. microorganisms have been shown to be both effective in compound transformation as well as resilient in high pH environment &#8211; characteristic for ISSA water mixtures. The course and efficiency of bioleaching was determined by the means of ICP methods. The chemical composition of ISSA, leachates, and the post-reaction residues were examined. Moreover, direct observation of interactions between the fungi and the ash was made by SEM-EDS.</span><span>&#160;</span></p> </div><div> <p><span>Apart from element recovery, both in case of use of ISSA for fertilization or for any other use (e.g. as an additive to cement), the toxicity of the ash must be examined and reduced.&#160;</span><span>&#160;</span></p> </div><div> <p><span>The course and effect of ISSA bioleaching by microorganisms was described. The study confirmed that phosphorus extraction as well as chemical neutralization of ash can be achieved using microorganism based bioleaching methods.</span><span>&#160;</span></p> </div><div> <p><strong><span>Acknowledgments: </span></strong><span>&#160;</span></p> </div><div> <p><span>This publication has been funded from the Anthropocene Priority Research Area budget under the program "Excellence Initiative &#8211; Research University" at the Jagiellonian University&#8221;. </span><span>&#160;</span></p> </div><div> <p><span>This publication has been&#160;f</span><span>inanced by Opus 17 Project 2019/33/B/NZ9/01372</span><span>&#160;</span></p> </div>