The goal of the pro­ject is to uti­li­ze biochar (also known as plant char­co­al or biochar) as a CO₂-neu­tral redu­cing agent in stamp-pres­sed agglo­me­ra­tes made from metall­ur­gi­cal resi­dues and bio­ge­nic bin­ders. For the first time, for­mu­la­ti­ons will be deve­lo­ped using inter­nal fine-grai­ned and iron-rich resi­dues along with sui­ta­ble bio­ge­nic bin­ders to pro­du­ce self-redu­cing agglo­me­ra­tes incor­po­ra­ting biochar, which will then be intro­du­ced into the mel­ting pro­cess of an iron foundry using a hot-blast cupo­la furnace.

The­se agglo­me­ra­tes enable the estab­lish­ment of CO₂-neu­tral inter­nal iron recy­cling loops for dust and sludge frac­tions gene­ra­ted in the steel and iron indus­try, which curr­ent­ly must still be land­fil­led due to tech­ni­cal and eco­no­mic rest­ric­tions. The­se mate­ri­al streams often con­tain immense amounts of oxi­dized iron that can poten­ti­al­ly be reco­ver­ed, ther­eby redu­cing the use of pri­ma­ry raw mate­ri­als. To achie­ve this, pre­vious­ly unu­sed bio­ge­nic resi­dues will be pyro­ly­zed, and the resul­ting bio­chars will be used as redu­cing agents. In addi­ti­on to the redu­cing pro­per­ties of biochar, the mecha­ni­cal pro­per­ties such as cold and hot com­pres­si­ve strengths of the pro­du­ced agglo­me­ra­tes are also a focus of inves­ti­ga­ti­on sin­ce the­se para­me­ters affect the fur­nace usa­bi­li­ty of the­se agglo­me­ra­tes. The pro­ject aims to adjust the mecha­ni­cal pro­per­ties through the addi­ti­on of bio­ge­nic bin­ders and sui­ta­ble bio­chars so that the agglo­me­ra­tes are sui­ta­ble for use in mel­ting pro­ces­ses at iron found­ries. Based on the results, tar­ge­ted recipes will be crea­ted, and agglo­me­ra­tes will be pro­du­ced to fur­ther demons­tra­te their usa­bi­li­ty in the steel and iron indus­try. The usa­bi­li­ty of the most pro­mi­sing agglo­me­ra­te for­mu­la­ti­ons will be demons­tra­ted within the pro­ject both at labo­ra­to­ry and pilot sca­le as well as in indus­tri­al-sca­le tri­als through their appli­ca­ti­on in the mel­ting ope­ra­ti­on at Issel­guss Iron Foundry. Throug­hout the enti­re pro­ject dura­ti­on, pro­cess and mate­ri­al para­me­ters will con­ti­nuous­ly be coll­ec­ted to allow for detail­ed eco­lo­gi­cal and eco­no­mic assessments.

With the deve­lo­ped method, lar­ge­ly cli­ma­te-neu­tral secon­da­ry raw mate­ri­als can be imple­men­ted for inter­nal recy­cling of iron car­ri­ers. Fur­ther­mo­re, almost exclu­si­ve­ly resi­du­al mate­ri­als are uti­li­zed in this descri­bed pro­cess, most of which are curr­ent­ly lar­ge­ly unu­sed or only ther­mal­ly pro­ces­sed. This leads to signi­fi­cant impro­ve­ments regar­ding cli­ma­te and envi­ron­men­tal aspects while making a sub­stan­ti­al con­tri­bu­ti­on to bio­e­co­no­my and cir­cu­lar eco­no­my through enhan­ced mate­ri­al flow management.