Mis­si­on Statement:

Pro­cess by-pro­ducts (PNP) occur­ring in metall­ur­gi­cal and mine­ral pro­ces­ses usual­ly still con­tain valuable metals such as cop­per, nickel and man­gane­se. The­se PNP are pre­sent in fine-grai­ned form, for exam­p­le in the form of fil­ter dusts, fil­ter sludge gra­nu­la­tes or cyclo­ne sepa­ra­ti­ons. If PNP accu­mu­la­te in lar­ge quan­ti­ties, they are curr­ent­ly most­ly bound by means of water and cement and pres­sed into bri­quet­tes with an edge length of 25 to 150 mm. The bri­quet­tes can then be reu­sed as raw mate­ri­al in the metall­ur­gi­cal indus­try. The dis­ad­van­ta­ge of this pro­cess is the lar­ge quan­ti­ties of CO2 released by hea­ting the bri­quet­tes to over 1000 °C and pro­du­cing the cement. The appro­xi­m­ate­ly 10 mil­li­on tons of PNP pro­du­ced annu­al­ly in Euro­pe are most­ly pro­du­ced decen­tral­ly in small quan­ti­ties of 1,000 to 35,000 tons per year per pro­duc­tion site. Often the PNP is land­fil­led at a cost of €36 to €45 per ton, as the­re is curr­ent­ly no simp­le, small-quan­ti­ty, eco­no­mic­al and space-saving method of making the PNP usable again. Thus, many valuable mate­ri­als are lost and the envi­ron­ment is hea­vi­ly pol­lu­ted. The aim of the pro­ject is to deve­lop an envi­ron­men­tal­ly fri­end­ly and eco­no­mic­al alter­na­ti­ve to bri­quet­ting PNP in order to feed it back into the metall­ur­gi­cal pro­cess. Cement will not be used and ins­tead fibers from used tex­ti­les will be used to bind the PNP. In addi­ti­on to saving lar­ge quan­ti­ties of CO₂ by dis­pen­sing with cement, the amount of water requi­red can also be signi­fi­cant­ly redu­ced. The eco­no­mic effi­ci­en­cy is made pos­si­ble by the fact that the land­fill cos­ts are eli­mi­na­ted and a rem­oval hall, which is neces­sa­ry with the usu­al PNP bon­ding, is no lon­ger requi­red. Thus, even the bin­ding of small quan­ti­ties of PNP should beco­me economical.

Approach:

The com­pac­tion of PNP is neces­sa­ry to feed it back into pro­ces­ses. Wit­hout com­pac­tion, the dusts would not reach the indus­tri­al fur­naces from the tech­ni­cal­ly neces­sa­ry extra­c­tion. Fiber rein­force­ment makes it pos­si­ble to pro­du­ce bri­quet­tes that are mana­geable for trans­port and use in indus­try. Fibers inves­ti­ga­ted in the rese­arch pro­ject should be harm­less to health, such as natu­ral fibers and syn­the­tic fibers (most­ly PET, PA, poly­o­le- fine). Fur­ther­mo­re, main­ly fibers that have been de-ponified or inci­ne­ra­ted so far will be inves­ti­ga­ted. In addi­ti­on to the fibers, bio­ge­nic starch will be used as a bon­ding agent based on suc­cessful preli­mi­na­ry tests. Over­all, the mea­su­res are expec­ted to result in CO2 savings of around 70% com­pared with con­ven­tio­nal methods.

In addi­ti­on to the increased envi­ron­men­tal fri­end­li­ne­ss, the tar­ge­ted pro­cess also has eco­no­mic advan­ta­ges for com­pa­nies. In addi­ti­on to the pro­cu­re­ment of cement, an addi­tio­nal hall is requi­red for curing the bri­quet­tes. The­se high invest­ment cos­ts can be signi­fi­cant­ly redu­ced by using fiber-rein­forced bri­quet­tes, so that the eco­no­mic via­bi­li­ty thres­hold is alre­a­dy excee­ded at a volu­me of 1,000 tons per year. In addi­ti­on to the spe­ci­fic appli­ca­ti­on for the bon­ding of PNP in the metall­ur­gi­cal indus­try, it is also con­ceiva­ble to use the tech­no­lo­gy in other are­as such as the pro­duc­tion of rock wool or for the sub­sti­tu­ti­on of lime­s­tone in cement clin­ker. The increased eco­no­mic effi­ci­en­cy is ensu­red, among other things, by the eli­mi­na­ti­on of land­fill cos­ts. In addi­ti­on, the cos­ts for the accep­tance of the used tex­ti­les can be expec­ted to be almost negli­gi­ble, sin­ce a fiber con­tent of less than 5% by weight can be expec­ted. In addi­ti­on, cos­ts are expec­ted to rise as land­fill space beco­mes scar­cer and land­fills are expec­ted to be ban­ned due to stric­ter envi­ron­men­tal regu­la­ti­ons. This would eli­mi­na­te the main dis­po­sal method for PNP.

Pro­jekt­struk­tur von DissHEAT