Co-processing of solid recovered fuels from mixed municipal and commercial waste in the cement industry - A pathway to a circular economy.

With global municipal solid waste generation increasing steadily, the importance of high-quality, environmentally friendly waste valorization methods is rising, too. Most countries have set themselves ambitious recycling goals and follow a waste hierarchy in which recycling is more preferable than energy recovery. This article focuses on a waste treatment option that already is an integral part of waste management in some countries and enables the simultaneous recovery of energy and mineral constituents: the production of solid recovered fuels (SRFs) from mixed municipal and commercial waste and their use in the cement industry is often referred to as co-processing. The state of the art of SRF production is described and the first comprehensive dataset for SRF samples including major constituents, heavy metal and metalloid contents, energy- and CO2-emission-relevant parameters, ash constituents and the material-recyclable share of SRF is presented. Additionally, a comparison with fossil fuels is given. It is concluded that SRF from state-of-the-art production plants complies with strict limit values for heavy metals, has an average biogenic carbon content of 60%, and its application in the cement industry can be considered as partial recycling (14.5%) and partial energy recovery (85.5%). Leaving no residues to be dealt with, co-processing of waste in the cement industry therefore offers many benefits and can support the shift from a linear to a circular economy.

Methods for identifying the material-recyclable share of SRF during co-processing in the cement industry.

Solid Recovered Fuels (SRF) include non-combustible mineral components (e.g. CaCO3, SiO2, Al2O3) that are required as raw materials for producing clinker and are completely incorporated into the clinker during the thermal recovery of SRF. This paper discusses simple and practicable ways of finding the relative amount of SRF that may be utilised as raw material (given as the recycling index). For this purpose, the entire mineral content of SRF was determined as the ash content and its main components were identified using different analytical methods.•A fusion melt of the previously incinerated sample with subsequent measuring using ICP-OES and XRF as well as a total digestion of the incinerated and non-incinerated sample with subsequent measuring using ICP-OES/ICP-MS were applied.•The results showed a good agreement of all four analytical methods for the elementary oxides Al2O3, CaO, Fe2O3, SiO2, TiO2, P2O5 and MgO (relative deviation from 6.6 to 38.9%) and slightly higher deviations for K2O, Na2O and SO3 (14.2-96.0%).•It was also shown that different incineration temperatures (550 °C, 815 °C and 950 °C) have no effect on the result of the recycling index unless it is assumed that the recycling index equals the ash content.

Arsenic-Containing Phosphatidylcholines: A New Group of Arsenolipids Discovered in Herring Caviar.

A new group of arsenolipids based on cell-membrane phosphatidylcholines has been discovered in herring caviar (fish roe). A combination of HPLC with elemental and molecular mass spectrometry was used to identify five arsenic-containing phosphatidylcholines; the same technique applied to salmon caviar identified an arsenic-containing phosphatidylethanolamine. The arsenic group in these membrane lipids might impart particular properties to the molecules not displayed by their non-arsenic analogues. Additionally, the new compounds have human health implications according to recent results showing high cytotoxicity for some arsenolipids.

Arsenic-Containing Phosphatidylcholines: A New Group of Arsenolipids Discovered in Herring Caviar.

A new group of arsenolipids based on cell-membrane phosphatidylcholines has been discovered in herring caviar (fish roe). A combination of HPLC with elemental and molecular mass spectrometry was used to identify five arsenic-containing phosphatidylcholines; the same technique applied to salmon caviar identified an arsenic-containing phosphatidylethanolamine. The arsenic group in these membrane lipids might impart particular properties to the molecules not displayed by their non-arsenic analogues. Additionally, the new compounds have human health implications according to recent results showing high cytotoxicity for some arsenolipids.