Fly ash is the most mineral residue left over from burning coal by coal-fired power plants. फ्लाइ एश पोजोलनिक हो, meaning that it has cementitious properties. It is valuable for

Vale do Reio Doce Company (CVRD) विश्वको सबैभन्दा ठूलो खानी कम्पनी हो. ब्राजीलमा मुख्यालय, तिनीहरूले खनन संचालन मा छ 30 संसार भरिका देशहरू. तिनीहरू