A powdered composite filtration medium includes composite particles that include at least one diatomite particle and at least one expanded perlite particle sintered together. The composite powdered filtration medium may include from about 7 wt% to about 90 wt% diatomite, from about 93 wt% to about 10 wt% expanded perlite. Less than about 1% total crystalline silica may be present in the medium. The medium may have a permeability of at least 0.25 darcy. The diatomite and expanded perlite may be sintered or calcined with or without a fluxing agent.
展开▼
