The present application belongs to the technical field of
water treatment, and specifically relates to a
siphon valveless filter tank for
water treatment and a
backwashing method. The filter tank comprises a filter tank main body, a water inlet
system, a filtering
system, a
backwashing system, a
clean water collecting system and a control valve
assembly. The inside of the filter tank is provided with, from top to bottom, a
clean water area, an ultra-high space, a sand washing tank, a
filter material layer, a supporting layer, an air-water
distributor and a water distribution area, and a vertical shaft water distribution channel is arranged in parallel on the side. The water inlet system eliminates the
air entrainment phenomenon through the vertical shaft water distribution channel. The
backwashing of the filter tank comprises two
modes of hydraulic
automatic control and
program control, and both
modes integrate air-water combined backwashing operation. The present application combines the advantages of homogeneous
filter material deep
bed filtration and hydraulic
automatic control, realizes air-water combined backwashing, and efficiently removes impurities in the filter layer. The filter tank has compact structure, is easy to operate and maintain, and can expand the treatment capacity of a single tank as needed, and is suitable for
water treatment scenes such as
water supply treatment,
sewage treatment and water purification, and is especially suitable for new construction and old
plant reconstruction of medium and small water plants.