On November 18th, 2020, China Concrete and Cement-based Products Association organized the scientific and technological achievement appraisal on-line meeting for the project entitled as "Production technology and complete set of equipment of lightweight aggregate prepared by modified three blades rotary kiln" ,which was completed by Shandong Hengyuan Solid Waste Utilization and Technology Co., Ltd (Shandong Hengyuan).

Industrial solid waste is a by-product of industrial production. At present, in a period of rapid economic development, the rapid development of industry leads to the rapid increasing emissions of solid waste. Solid waste storage not only occupied a lot of land, but also causes a lot of soil and water pollution, which seriously affects the people's production and life. Filling land, drying, composting, resource utilization are the existing main disposal treatments of solid waste.

Compared with these treatments above, Shandong Hengyuan developed the technology of high-performance lightweight aggregate prepared by modified three blades rotary kiln, which has the characteristics of low cost, less area occupancy and no secondary pollution. It can not only realize the harmless treatment of solid waste, but also product the high-performance lightweight aggregate from solid waste. Lightweight aggregate prepared by modified three blades rotary kiln is a comprehensive utilization of resources. In the project entitled as "Production technology and complete set of equipment of lightweight aggregate prepared by modified three blades rotary kiln", the main research contents are as follows:

l core equipment

l a complete set of energy saving and environmental protection equipment and process

l automatic control system

l collaborative treatment of different kinds of solid waste.

Modified three blades rotary kiln

Vertical turbulent mixer

Appearance and SEM of lightweight aggregate made of fly ash

Key technologies and innovations are as follows:

l On the basis of the introduced technology, the modified three blades rotary kiln with high efficiency and energy saving is developed, which realizes the heat exchange and uniform sintering of materials, and has the technical characteristics of small floor area and high thermal efficiency.

l Vertical turbulent mixer and granulation equipment for mixture with high moisture content are developed independently. With these, the research team formed a complete set of key technical equipment for efficient pretreatment of materials, including vibrating fluidized dryer.

l Dust collection, desulfurization, deodorization and other systems are equipped to establish a complete set of environmental protection and emission reduction technology. At the same time, the route of "low temperature drying + high temperature roasting + rapid cooling" could provide technical support to the safety disposal and resource utilization of various sludge and industrial solid waste.

l The PLC / DCS automatic control system is developed to realize online remote monitoring.

This project have been carried out in Shouguang, Weifang and other cities in Shandong Province for collaborative disposal of sludge, inferior fly ash and other solid waste, and four high-performance lightweight aggregate production lines have been established. Meanwhile, this project has expanded the application field to the harmless collaborative disposal of hazardous waste, and started the annual processing of 100000 tons of hazardous waste HW17 to prepare lightweight aggregate in Tianjin. The high-performance lightweight aggregate produced by this project has been successfully used in many construction engineering. This achievement promotes the technological progress of lightweight aggregate industry, and has broad market application prospects.