Design, quality and quality assurance of solid recovered fuels for the substitution of fossil feedstock in the cement industry - Update 2019.

Production, quality and quality assurance, as well as co-incineration of solid recovered fuels in cement industry, have become state-of-the-art in the European cement industry. At the global level, average thermal substitution rate is about 17%, whereby, only 13% in Canada and in the USA 16%, while in the European Union 28 it is about 44% (i.e. 11,300,000 t waste fuels utilised in 2016). In Austria, thermal substitution rate was ca. 80% in 2017, which was worldwide the highest one. Regarding solid recovered fuels for the cement industry, two types are relevant, namely solid recovered fuels PREMIUM Quality and solid recovered fuels MEDIUM Quality. In the case study shown, solid recovered fuels PREMIUM Quality from 11 and solid recovered fuels MEDIUM Quality from nine different solid recovered fuels production plants have been investigated. Investigations consist of sorting and sieving analyses (for PREMIUM), as well as physical-chemical analyses (for both solid recovered fuels types) according to the (inter)national standards (i.e. Austrian 'ÖNORM', European 'EN' standards and CEN TC 343 guidelines). The results gained from the first investigation were published in 2014 and here, results of further investigations are updated for 2016 and 2018 and confronted with legal and market relevant requirements. During the investigation, not enough parallel samples could be investigated and therefore no adequate scientific statistical analyses could be elaborated but a more practical indicative interpretation has been made. Finally, it can be confirmed, that all investigated solid recovered fuels fulfil the Austrian legal and international solid recovered fuels and co-incineration market requirements.

Digitalisation and intelligent robotics in value chain of circular economy oriented waste management - A review.

The general aim of circular economy is the most efficient and comprehensive use of resources. In order to achieve this goal, new approaches of Industry 4.0 are being developed and implemented in the field of waste management. The innovative K-project: Recycling and Recovery of Waste 4.0 - "ReWaste4.0" deals with topics such as digitalisation and the use of robotic technologies in waste management. Here, a summary of the already published results in these areas, which were divided into the four focused topics, is given: Collection and Logistics, Machines and waste treatment plants, Business models and Data Tools. Presented are systems and methods already used in waste management, as well as technologies that have already been successfully applied in other industrial sectors and will also be relevant in the waste management sector for the future. The focus is set on systems that could be used in waste treatment plants or machines in the future in order to make treatment of waste more efficient. In particular, systems which carry out the sorting of (mixed) waste via robotic technologies are of interest. Furthermore "smart bins" with sensors for material detection or level measurement, methods for digital image analysis and new business models have already been developed. The technologies are often based on large amounts of data that can contribute to increase the efficiency within plants. In addition, the results of an online market survey of companies from the waste management industry on the subject of waste management 4.0 or "digital readiness" are summarized.

Dynamic visualisation of municipal waste management performance in the EU using Ternary Diagram method.

This contribution describes the dynamic visualisation of European (EU 28) municipal waste management performance, using the Ternary Diagram Method. Municipal waste management performance depends primarily on three treatment categories: recycling & composting, incineration and landfilling. The framework of current municipal waste management including recycling targets, etc. is given by the Waste Framework Directive - 2008/98/EC. The proposed Circular Economy Package should stimulate Europe's transition towards more sustainable resources and energy oriented waste management. The Package also includes a revised legislative proposal on waste that sets ambitious recycling rates for municipal waste for 2025 (60%) and 2030 (65%). Additionally, the new calculation method for monitoring the attainment of the targets should be applied. In 2014, ca. 240 million tonnes of municipal waste were generated in the EU. While in 1995, 17% were recycled and composted, 14% incinerated and 64% landfilled, in 2014 ca. 71% were recovered but 28% landfilled only. Considering the treatment performance of the individual EU member states, the EU 28 can be divided into three groups, namely: "Recovery Countries", "Transition Countries" and "Landfilling Countries". Using Ternary Diagram Method, three types of visualization for the municipal waste management performance have been investigated and extensively described. Therefore, for better understanding of municipal waste management performance in the last 20years, dynamic visualisation of the Eurostat table-form data on all 28 member states of the EU has been carried out in three different ways: 1. "Performance Positioning" of waste management unit(s) at a specific date; 2. "Performance dynamics" over a certain time period and; 3. "Performance development" expressed as a track(s). Results obtained show that the Ternary Diagram Method is very well suited to be used for better understanding of past developments and coherences, for monitoring of current situations and prognosis of future paths. One of the interesting coherences shown by the method is the linked development of recycling & composting (60-65%) with incineration (40-35%) performance over the last 20years in the EU 28.

Design, quality, and quality assurance of solid recovered fuels for the substitution of fossil feedstock in the cement industry.

This paper describes the requirements for the production, quality, and quality assurance of solid recovered fuels (SRF) that are increasingly used in the cement industry. Different aspects have to be considered before using SRF as an alternative fuel. Here, a study on the quality of SRF used in the cement industry is presented. This overview is completed by an investigation of type and properties of input materials used at waste splitting and SRF production plants in Austria. As a simplified classification, SRF can be divided into two classes: a fine, high-calorific SRF for the main burner, or coarser SRF material with low calorific value for secondary firing systems, such as precombustion chambers or similar systems. In the present study, SRFs coming from various sources that fall under these two different waste fuel classes are discussed. Both SRFs are actually fired in the grey clinker kiln of the Holcim (Slovensko) plant in Rohoznik (Slovakia). The fine premium-quality material is used in the main burner and the coarse regular-quality material is fed to a FLS Hotdisc combustion device. In general, the alternative fuels are used instead of their substituted fossil fuels. For this, chemical compositions and other properties of SRF were compared to hard coal as one of the most common conventional fuels in Europe. This approach allows to compare the heavy metal input from traditional and alternative fuels and to comment on the legal requirements on SRF that, at the moment, are under development in Europe.

Implementation of fluidized granulated iron reactors in a chromate remediation process.

A new approach concerning in-situ remediation on source ('hot-spot') decontamination of a chromate damage in connection with an innovative pump-and-treat-technique has been developed. Iron granulates show significant higher reduction rates, using fluidized bed conditions, than a literature study with a fixed bed installation of small-sized iron granules. First results from an abandoned tannery site concerning injections of sodium dithionite as a chromate reductant for the vadose zone in combination with a pump-and-treat-method, allying the advantages of granulated zero valent iron (ZVI), are reported. Reduction amounts of chromate have been found up to 88% compared with initial values in the soil after a soil water exchange of 8 pore volumes within 2.5 months. Chromate concentrations in the pumped effluent have been reduced to under the detection limit of 0.005 mg/L by treatment with ZVI in the pilot plant.

Production, quality and quality assurance of Refuse Derived Fuels (RDFs).

This contribution describes characterization, classification, production, application and quality assurance of Refuse Derived Fuels (RDFs) that are increasingly used in a wide range of co-incineration plants. It is shown in this paper, that the fuel-parameter, i.e. net calorific value [MJ/kg(OS)], particle size d(90) or d(95) [mm], impurities [w%], chlorine content [w%], sulfur content [w%], fluorine content [w%], ash content [w%], moisture [w%] and heavy metals content [mg/kg(DM)], can be preferentially used for the classification of different types of RDF applied for co-incineration and substitution of fossil-fuel in different industial sectors. Describing the external production of RDF by processing and confectioning of wastes as well as internal processing of waste at the incineration plant, a case study is reported on the application of RDF made out of different household waste fractions in a 120,000t/yr Waste to Energy (WtE) circulating fluidized bed (CFB) incinerator. For that purpose, delivered wastes, as well as incinerator feedstock material (i.e. after internal waste processing) are extensively investigated. Starting with elaboration of sampling plan in accordance with the relevant guidelines and standards, waste from different suppliers was sampled. Moreover, manual sorting analyses and chemical analyses were carried out. Finally, results of investigations are presented and discussed in the paper.

Irrigation model of bleached Kraft mill wastewater through volcanic soil as a pollutants attenuation process.

An irrigation process through volcanic soil columns was evaluated for bleached Kraft mill effluent pollutants retention. The system was designed to remove color and phenolic compounds and a simple kinetic model for determining the global mass transfer coefficient and the adsorption rate constant was used. The results clearly indicate that the global mass transfer coefficient values (K(c)a) and the adsorption rate constants are higher for the irrigation processes onto acidified soil. This means that the pretreatment of washing the volcanic soil with an acid solution has a positive effect on the adsorption rate for both pollutant groups. The enhanced adsorption capacity is partially explained by the activation of the metal oxides present in the soil matrix during the acid washing process. Increasing the flow rate from 1.5 to 2.5 ml/min yielded higher (K(c)a) values and adsorption rate constants for both pollutant groups. For instance, regarding color adsorption onto acidified soil, there is an increment of 43% in the (K(c)a) value for the experiment with a flow rate of 2.5 ml/min. Increasing the porosity of the column from 0.55 to 0.59, yielded a decrease in the (K(c)a) values for color and phenolic compounds adsorption processes. Onto natural soil for example, these decreases reached 21% and 24%, respectively. Therefore, the (K(c)a) value is dependent on both the liquid-phase velocity (external resistance) and the soil fraction in the column (internal resistance); making forced convection and diffusion to be the main transport mechanisms involved in the adsorption process. Analyzing the adsorption rate constants (K(c)a)/m, phenolic compounds and color adsorption rates onto acidified soil of 2.25 x 10(-6) and 2.62 x 10(-6) l/mg min were achieved for experiment 1. These adsorption rates are comparable with other adsorption systems and adsorbent materials.

In-series columns adsorption performance of Kraft mill wastewater pollutants onto volcanic soil.

Two in-series columns systems with volcanic soil were tested for wastewater pollutants adsorption capacity. The first system was tested with acidified volcanic soil and the second with a reactivated volcanic soil. The reactivated soil was obtained by washing the previous spent acidified soil system with an acid solution. The systems parameters were obtained using the Bohardt and Adams model for fixed-beds. The acidified soil parameters indicated an adsorption capacity q of 28 and 139 mg/g of phenolic compounds and color, respectively (for each column), compared to 12 and 39 mg/g for the reactivated soil system. The adsorption rate constant k ranged between 1.5x10(-6) and 2.8x10(-6) l/min mg and no significant difference was observed for each analysed column system and pollutant. Furthermore, the molecular weight distribution analysis of input and output samples of one acidified soil column indicated that the fraction >30000 Da is the most adsorbed until the breakpoint. Moreover, the CODs and tannins and lignin removal efficiencies at the breakpoint reached values between 60% and 70% in each column and each system, indicating that lower biodegradable compounds were retained effectively. The results indicate that it is possible to compare the acidified volcanic soil adsorption capacity with natural zeolites, and a preliminary costs evaluation indicates that volcanic soil could be also competitive, even when comparing with activated carbon.

Mass spectral identification of metabolites formed by microbial degradation of polycyclic aromatic hydrocarbons (PAH).

This paper deals with the identification of PAH metabolites, which are formed during PAH bioremediation. The investigation was performed with trimethylsilylation (TMS) of the sample, following gas chromatographic (GC) separation and mass spectrometry (MS). The mass spectra were analysed, rules of fragmentation developed and characteristic fragments were presented.