BACK WASHING TYPE SPRING FILTRATION DEVICE

• Main Author: UCHIYAMA SHIGENOBU
• Format: Patent
• Language: English
• Published: 09.10.2001
• Edition: 7
• Subjects: PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

PROBLEM TO BE SOLVED: To easily wash out the fine particles of a filter bed formed by depositing the fine particles having minute communicating pores, such as the powder of diatomaceous earth, onto the outer periphery of a closely wound coil where a projection of a prescribed height is installed and gaps are formed in a closely wound part, in layers, when back-washed. SOLUTION: The push rod 3 of a float 1 having a self-weight heavier than the initial load of the closely wound coil 24 and receiving buoyancy greater than the self-weight is inserted from a filtration water tank 21 side into the closely wound coil 24 located on a sewage tank 20 side through the communicating hole 23 of a partition wall 22. When back-washed, the float 1 goes down as the water level of the filtration water tank 21 lowers, and it loads its self- weight on the bottom plate 26 of the closely wound coil 24 with the push rod 3 to expand the coil 24, thereby removing the force of constraint of the fine particles 28 for filtration biting a part of the gap 25 of the coil 24 with filtration resistance to surely wash out the particles.