belite sludge(= нефелиновый шлам. ... in an industrial process by mixing, sintering or melting different materials (clay, marl, zeolite, metakaolin, red mud, slag, fly ash, belite sludge, ground rock, etc.) ... Alexander Demidov)
converter slag(The converter slag is usually recycled to the smelting stage due to the high content of copper in this by-product. Converter gas contains more than 10% of sulfur ... WK Alexander Demidov)
