Bio-regeneration for Sodium Silicate Used Sands and its Unattended Monitoring System

Abstract

Sodium silicate, known for its low cost and non-toxicity, has been considered as a promising option for green foundry in terms of mould sands. However, the utilization of used sodium silicate sands has posed significant challenges. To address the issues of high energy consumption and secondary pollution associated with wet and dry regeneration of sodium silicate used sands, this paper proposes a novel unattended biological regeneration system. The system involves culturing diatoms in an incubator with a solution of sodium silicate used sands. The incubator is equipped with built-in sensors that continuously monitor temperature, illuminance, pH, and water level. The monitoring data is transmitted in real-time to the Yeelink Internet of Things platform via the controller using the TCP/IP protocol. By logging onto the corresponding web page, the experimenter can remotely observe the monitoring data. The results of the experiment indicate that diatoms bloomed five times, and the water pH decreased from 10.2 to 8.2 after 40 days of cultivation. Additionally, the film removal rate of the used sands reached 90.26%.