International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The treatment of technological wastewater through a neutralization process is essential for adjusting the chemical properties of the water. This method aims to ensure that the wastewater meets established discharge limits, thereby protecting aquatic ecosystems and improving water quality in local waterways. Effectively managing process wastewater from large industrial facilities, such as copper rolling mills, presents a significant challenge that requires attention. In this paper, we present experimental testing of the neutralization process for technological wastewater from copper rolling mills, conducted at laboratory levels. Experimental research has shown that the neutralization process involves adding 10% Ca(OH)2 until a pH of 8.5 is achieved. The duration of the neutralization process is 30 minutes. During this time, a flocculant called Settafloc AP-17 is added at a concentration of 0.033%, specifically 6 ml per liter. This method effectively meets the water quality standards outlined in the Regulation on Limit Values of Pollutant Emissions into Water and the deadlines for compliance.

Researches in this paper included characterization of bismuth telluride single crystal doped with selenium. In order to study the effect of Se doping on the thermoelectric properties of Bi2Te2.7Se0.3 single crystal, an ingot was prepared by Bridgman method. The Bi2Te2.7Se0.3 single crystal in 11 mm × 80 mm size was grown.
The obtained empirical formula does not deviate from the given compound formula. Bulk sample was characterized by Seebeck coefficient (S) as а function of temperature in the range of 40 – 320°C by а homemade impedance meter.