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In order to analyse the feasibility of sintering for municipal sludge treatment, a sintering pot was used for the experiment. The results showed that the main effects of sludge addition on the sintering process and sinter quality come from the changes in the heat addition and moisture content of the granulated sinter. The addition of sludge could improve the granulation efficiency of the sinter mixture and the particle size composition of the sinter. When the proportion of sludge was 7%, the addition of sludge completely replaced the water required for mixing, and the overall sintering index was the best. In this case, after reducing fuel consumption by 10%, except for the content of P, the sinter quality and the sintering index could met the requirements of steel production. Finally, the use of fuel and raw materials with high P content needed to be reduced with the addition of sludge. [ABSTRACT FROM AUTHOR] more...

Fly ash, a significant byproduct of municipal solid waste incineration, garners attention for its harmless treatment and resource utilisation. Existing research has demonstrated the viability of incorporating fly ash into the sintering process and explored its influence on the sintering bonding phase. In the context of co-disposal of municipal solid waste incineration residues through sintering, it is imperative to consider the mineralisation characteristics, necessitating a comprehensive evaluation of sinter strength and metallurgical performance. In this investigation, the process is validated on an expanded scale using sintering cup experiments. The results indicate that the experimental group with a basicity of 2 and the inclusion of fly ash exhibits sinter strength in line with actual production requirements, its drop index is 76.03%, and its drum index is 77.2%. Additionally, the reduction velocity index is recorded at 0.573% min−1, the reduction degradation index for RDI+3.15 at 92% and the total characteristic value of melting properties ( S ) at 99.175 KPa·°C—nearly equivalent to the control group with matching alkali conditions. The technology roadmap was verified by sintering cup experiment, offering vital theoretical support for the development of sintering process in the collaborative treatment of incineration fly ash. [ABSTRACT FROM AUTHOR] more...

Fluctuations in the sintering process have a significant impact on the overall performance and outcomes of sintering production. It is crucial to gain a comprehensive understanding of the sintering operation in a timely manner in order to minimise process fluctuations and ensure the stability of sinter production. In this paper, a sintering process evaluation model is presented, which is based on the analytic hierarchy process–entropy weight method–technique for order preference by similarity to an ideal solution (AHP–EWM–TOPSIS) and is constructed using data from a steel plant sintering production process. Firstly, the evaluation indices input to the system are selected by combining the principle of the sintering process and actual production requirements. The subjective and objective weights of the indices are then calculated using the AHP–EWM method, and the weights are combined through the principle of minimum discriminatory information to construct the set of weighted indices. Subsequently, the sintering process was evaluated by the TOPSIS model, and the results of this evaluation were compared with the actual fluctuation situation at the sintering site. This was done by combining the model results with the differential level method. It was found that the model can accurately reflect the fluctuation situation that occurs in the sintering process. Furthermore, the comprehensive matching rate reached 95.42%, which demonstrates that the model is capable of accurately evaluating the operation of the sintering process. The statistical analysis of historical data provides a basis for the optimised operation of the sintering production process by summarising the optimal range of each parameter when the sintering operates efficiently. Ultimately, a sintering process evaluation system is constructed through the use of computer technology, thereby facilitating the transformation of sintering production into an intelligent system. The model is capable of rapidly ascertaining the actual status of the sintering process in real time. The established system is designed to facilitate the optimisation of sintering production operations and to promote long-term stability in sintering. [ABSTRACT FROM AUTHOR] more...

In response to the phenomenon of automatic heat storage during the sintering process of iron ore, heat balance analysis concerning the main chemical reactions and physical heat carried by gas and solid materials was conducted. A unit heat storage model for the sintering process was established. Further, a mathematical model to solve the heat transfer characteristics between different sintering layer units was proposed and established based on temperature–time curves of the gas and solid phases. Using these models, the heat storage of each layer unit was calculated under the condition of uniform carbon allocation. Subsequently, the optimisation of carbon allocation at each layer unit for maximising the utilisation of heat storage was investigated. The heat required for sintering by the layer unit was taken as the constraint, and the maximum utilisation of heat stored in each layer unit was taken as the goal to optimise the carbon allocation in the height direction. The calculation results show that as the unit thickness is 100 mm and the total thickness of the layer is 600 mm, the heat transfer ratio of the upper unit to the lower unit is 34.22%, 30.29%, 14.74%, 9.49%, and 1.17%, respectively. The heat storage and available heat storage rate increase with the increase of layer height, with heat storage ranging from 0.69 × 104 to 5.14 × 104 KJ/t and heat storage rate ranging from 11.63% to 49.37%. After optimising carbon allocation, the unit achieved a maximum carbon reduction of 60.04%, resulting in an overall reduction in carbon allocation of 46.20%. This adjustment aligns more closely with the industrial processes. [ABSTRACT FROM AUTHOR] more...

The accurate prediction of SO2, NOx and PM emissions in the iron ore sintering process could adjust the desulfurization and denitrification operation in time. The study presented an integrated prediction model for SO2, NOx and PM in sintering flue gas. Gradient boosting decision tree, recurrent neural network, gated recurrent unit were chosen as sub-models to predict SO2, NOx and PM by comparing different regression prediction models, which were then combined to form an integrated prediction model (MMEP). The box plots, empirical mode decomposition algorithm, Pearson correlation coefficient and maximum information coefficient to select independent variables for the predictive model. The MMEP model had an overall accuracy greater than 0.82, as verified by production data, which could provide guidance for on-site sintering production. [ABSTRACT FROM AUTHOR] more...

Cold agglomeration experiments were made in order to investigate the effect of three binders with different chemical composition (sodium polyacrylamide, cellulose derivate and a specific Brazilian mineral coal) and the addition of pellet feed in the sintering mixture, on the efficiency of granulation, evaluated by the mean particle size of the agglomerate and microstructure of the micro pellets. The binder that produced the highest mean particle size was used in new cold agglomeration experiments in order to indirectly evaluate the mechanical strength of the agglomerate. The experiments showed that only the cellulose derivate binder was capable of producing agglomerates with equal or greater mean particle size when compared with the base test for practically all performed tests, regarding the values of d50 and Sauter mean diameter, besides promoting the increase on the adhering layer thickness and stability of the nuclei-adhering layer interface of the micro pellets. [ABSTRACT FROM AUTHOR] more...

This paper presents an integrated approach for SO2 reduction and energy conservation by recycling waste gas during the iron ore sintering process. We established a mathematical model for the sintering flue gas temperature (SDG-T) and SO2 content (SDG-SC), and analysed the influences of the raw materials (carbon and moisture contents) and operation parameters (sinter bed height and speed). Correspondingly, we develop a novel optimisation framework for the design of the sintering process. Using the proposed integrated approach along with a 360 m2 sinter from Anshan Iron and Steel Co., Ltd (An Steel) as an example, we have considered the SO2 captured by the waste heat resources during the sintering process. Finally, we compare our design approach with that of the conventional approach to verify the capability of our proposed approach in capturing SO2 using recycled waste gas. [ABSTRACT FROM AUTHOR] more...

The iron ore blend for sintering depends to a great extent on ore properties. It is hard to determine the final sinter reducibility from the reducibility and ratio of single iron ores in a mixture. For production cost reduction, optimised blending ratios were designed according to ore prices and properties (microstructure, crystal water decomposition, assimilation ability, liquid phase fluidity), ensuring nearly identical chemical composition as the mixture used in actual sintering. Sinter pot tests were conducted to determine the optimum mix. The results indicate that properties of iron ores vary greatly, which should be considered for the design of ore blending ratio. The total content of the two Australian ores tested should not exceed 45%. The cost of sintering process could be further reduced together with an improvement of economic and technical indices, only by ratio adjustment of present ores. [ABSTRACT FROM AUTHOR] more...

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