00545naa#a2200181#i#450# EN\\bibl\92088 20250905150502.5 3034-4689 20250801b2025####ek#y0engy0150####ca RU PURIFICATION OF FUEL OIL-CONTAINING BOILER WASTEWATER IN A HYDROCYCLONE-FILTERING UNIT Journal article Kazan Kazan National Research Technological University 2025 4 с. Journal article local Busarev A V Selyugin A S vestniktu.ru