Hot-rolled strips are cooled on the run-out table to achieve the customer-required mechanical properties. Cooling reduces the oxidation, which can assist the coiling operation. The ability to obtain ...a range of mechanical properties from a single steel grade reduces the use of alloying elements (elements added to a metal or an alloy which are incorporated in the metallic structure and change in the properties of the basic alloy) and the size of the slab inventories. So in this paper, the high-temperature steel strip cooling pattern with the temperature of 870 °C and reaching the temperature of 630 °C using water and air is studied. Moreover, the numerical simulation of the high-temperature strip cooling and its cooling method is carried out. The results are compared with the similar sampler ones. The changes of three key parameters such as change in strip speed and its effect on cooling rate, change in pattern and arrangement of water showers and its effects and change in the cooling water temperature are investigated. It was found that the uniformity of the heat distribution inside the strip was increased, but the temperature of the strip was lower than the required temperature. The middle and up surface temperatures of the strip were performed at a speed of 3.48 (m s
−1
), which showed a very good match with the actual tested sample.
•A novel trigeneration system for waste heat recovery of slag in steelmaking plant was proposed.•The cycle includes biogas production system from wastewater and sewage.•Energy, exergy, economic (3E) ...analyses and performances of the cycle under different objectives are performed.•Accroding to 3E analysis, the exergy unit cost of output power, cooling and heating were determined 30.14 $/h, 28.73 $/h and 29.25 $/h, respectively.•Effects of different ORC working fluids on the system performance are compared.
This study presents an analysis of a combined heating, cooling and power cycle that recovers the thermal energy of waste steel slag. The cycle utilizes the biogas produced from anaerobic digestion process of wastewater and sewage of residential areas. A thermodynamic model used for the trigeneration cycle and the performance of the cycle investigated from exergy and exergy-economic aspects. The power production capacity of the cycle, the cooling capacity and hot water production rate achieved 700 kW, 40 tons of refrigeration and 29400 kg/h, respectively. Also, the results of exergy-economic analysis indicate that the costs of power exergy, cooling and heating produced by the combined cycle are 30.14 $/h, 28.73 $/h and 29.25 $/h, respectively. Among six working fluids that examined for the organic Rankine cycle, R123 had the highest efficiencies (16% to 28%) in the turbine inlet temperature range of 200 °C to 420 °C and the highest output power was about 50 kW. Moreover, the highest growth rate of exergy efficiency and power generation in this temperature range observed when HFE7000 used as the working fluid.
