在实验室规模的实验中研究了接触过滤（在颗粒失稳后对湖水进行深层过滤，但不进行其他处理）。在四个不同深度测量了几个小时的粒度分布和压力，在这段时间内，过滤器性能通常会改善，即发生熟化。粒度分布测量与浊度和悬浮固体测量一致，但提供了更详细的信息。所有尺寸的颗粒最初都会成熟，小尺寸的颗粒会持续几个小时，但较大颗粒的成熟会减慢或逆转。增大的介质尺寸（从0.8 mm增加到1.85 mm）允许使用整个床层进行移除，并减少水头损失，尽管同等移除需要更大的深度。过滤速度也会影响去除效率、床层深度使用和水头损失，但影响程度小于介质尺寸。 包括41个参考文献、表格、图表。

Contact filtration (deep-bed filtration of lake water after particle destabilization but no other treatment) was studied in laboratory-scale experiments. Particle size distributions and pressure were measured at four different depths for several hours, the time over which filter performance generally improves, i.e., ripening occurs. Particle size distribution measurements coincided with measurements of turbidity and suspended solids but provided more detailed information. Ripening occurred for all sizes initially and continued for small sizes for several hours, but it slowed or reversed for larger particles. Increased media size (from 0.8 to 1.85 mm) allowed use of the entire bed for removal and reduced head loss, although greater depth was required for equivalent removal. Filtration velocity also affected removal efficiency, bed depth use, and head loss--but to a lesser extent than media size. Includes 41 references, table, figures.