In focus is waste management-utilization of screenings after volcanic rock crushing at broken stone production plants. The authors formulate causes of increased production of screenings and their poor utilization. The composition and properties of screenings of granite, gabbro and hornblendite are determined. High content of dust particles limits the use of screenings in production of concrete and mortar. It is proposed to remove dust from screenings by pneumatic treatment. The test data on air separation of screenings by cross-flow classifier are reported. The efficiency of dry processing of screenings is checked in tests of treated sand behavior in composition of heavy concrete. It is shown that treated sand enhances strength of concrete.