... distribution is uneven, will lead to Recoil uniform degree of inconsistency of the filter layer, resulting in filter local backwash ... ratio, fine aggregate, quartz sand grading science, strict implementation of national standards, according to design requirements in the hole , ... specifications is 960 × 960 × 100mm and 980 × 980 × 100mm (length × width × height),the filter head standard is (6×3)/m2,(6×6 ...