China
Africa
Explore chapters and articles related to this topic
Manufacture and processing
Published in Peter Domone, John Illston, Construction Materials, 2018
The key constituent is sand, which provides the silica (SiO2) matrix, and glass making historically evolved in locations with a source of pure silica sand. Pure silica melts sharply at about 1600°C and forms a dense glass with high refractive index on cooling. On slow cooling in nature, silica forms crystals of quartz or coloured gem stones like amethyst, ruby and sapphire according to the presence of small amounts of impurities (elements other than silicon). The high melting temperature and narrow temperature range over which the material can be formed make pure silica glasses impractical for most purposes.
An approach to recovering heat from the compressed air system based on waste heat recovery: a review
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2023
Rohit P. Sarode, Shilpa M. Vinchurkar
Waste heat recovery is crucial in a wide range of sectors. Examples of places where waste heat is recovered include air compressor unit (Saidur, Rahim, and Hasanuzzaman 2010; Valenti, Valenti, and Staboli 2019), expanding natural gas (Englart et al. 2019; Jedlikowski et al. 2020), flue gas facilities (Dudkiewicz and Fidorów-Kaprawy 2020; Dudkiewicz and Szałański 2020) that recover heat from air conditioning units (Ramadan, Rab, and Khaled 2015), heat recovery from ventilation air (Kowalski, Szałański, and Cepiński 2021), recover low-grade heat from turbine exhaust steam (Wang et al. 2020) in order to use it as a source of low-grade heat recovery in industrial and data centers (Luo et al. 2019), as well as cooking waste, and other sources of wastewater (El Hage et al. 2020). According to McKenna and Norman, the UK’s most significant sources of industrial waste heat include ceramics, paper and pulp, cement, glassmaking, refineries, iron and steel, as well as the food and beverage sectors (McKenna and Norman 2010).
Numerical study to recover low-grade waste heat using pulsating heat pipes and a comparative study on performance of conventional pulsating heat pipe and additional branch pulsating heat pipe
Published in Numerical Heat Transfer, Part A: Applications, 2023
Kommuri Satyanarayana, Nakka V. S. M. Reddy, Srinivasan Venugopal
Heat is discharged into the atmosphere as waste heat during all energy generating and mechanical industrial processes (such as steam and gas power plants, steel, cement, ceramic, glassmaking industries, and refineries). Waste heat is discharged in many ways, including the dispersion of hot combustion gases into the atmosphere, the release of hot water (as a by-product of the process) into the environment, and surface heat transfer from the equipment’s [1]. Waste heat is categorized into three grades based on temperature: high grade waste heat (>650 °C), medium grade waste heat (120–650 °C), and low-grade waste heat (<120 °C) [2]. Low-grade waste heat sources include heat dissipated from combustion and heat loss from industrial equipment, processes, and products [3–7]. Because low-grade waste heat has traditionally not been used for power generation, heat exchangers to recover low-grade waste heat would be preferred than thermoelectric units [2]. Heat pipe technology is widely used as a heat recovery device in various engineering applications (chemical, mechanical, and energy) [8–11]. Researchers are interested in using heat pipes as a heat exchanger because of their compactness, light weight, lack of mechanical parts, and less maintenance cost.