Liquid purification or separation – With means to add treating material – Spaced along flow path
Reexamination Certificate
2001-09-20
2004-08-17
Hruskoci, Peter A. (Department: 1724)
Liquid purification or separation
With means to add treating material
Spaced along flow path
C210S202000, C210S203000, C210S207000, C210S253000, C210S151000
Reexamination Certificate
active
06776903
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a system and method for waste water treatment wherein energy saving and reduction of suspended solids by digestion can be achieved. The present invention also relates to a waste-water treatment system constituted by solely using an attachment filter having a sedimentation section or combining an attachment filter and a rapid filter. The present invention further relates to a waste-water treatment system capable of performing a highly efficient treatment of organic matters and an advanced treatment of suspended solids (two-stage filtration).
In an age of global environmental protection, an important issue for any company is how to reduce various wastes generated in its operation centers.
Furthermore, reduction of waste has become a recent important issue from viewpoints of recent reduction of the number of disposal sites and recent efforts towards zero emission by various companies.
Similarly, an issue of sludge generated from waste-water treatment equipment is also being grappled with in various manners.
Solids suspended in waste water is filtered until its amount falls in a range of regulation values or removed by coagulating sedimentation using a chemical or the like. Therefore, sludge is generated after the treatment.
Conventionally, a rapid filter as a filter employed in a common waste-water treatment system is composed of a water-conveying pump and backwash pump. Power consumption was high, in particular, due to a long running time of the water-conveying pump.
However, energy saving measures for the equipment has become so important today that it has become necessary to thoroughly plan and implement energy saving in the waste-water treatment system as well.
However, as long as the rapid filter is used, energy saving measures relevant to pumps for use in the rapid filter have approached their limit, thereby making energy saving substantially difficult. Furthermore, the rapid filter does not have a function for digesting and reducing suspended solids in waste water.
On the other hand, a biological filter consumes a relatively little electrical energy. However, there were cases microorganisms exfoliated from the biological filter deteriorated water quality.
One example of such conventional techniques having a biological filter (Japanese Patent Laid-Open Publication HEI 9-314163) is described below. This conventional technique provides a waste-water treatment system wherein waste water is introduced into a charcoal tank filled with charcoal for treatment and then the waste water from this charcoal tank is introduced into an activated carbon tower filled with activated carbon for treatment.
Since microorganisms are propagated in both the charcoal in the charcoal tank and the activated carbon in the activated carbon tower, these are called biologically activated charcoal and biologically activated carbon, respectively. This two-stage treatment by the biologically activated charcoal and the biologically activated carbon has a merit that a backwash process and a reproduction process in the activated carbon tower are not required. Consequently, the life of the activated carbon can be substantially extended.
Since a biofilm is also formed on the surface of the biologically activated charcoal and waste water constantly circulates in a water tank by aeration, aerobic biofilm filtration is performed by the biologically activated charcoal. That is, biological filtration is constantly performed. Although charcoal is also a packing material, anaerobic digestion of sludge by microorganisms cannot be expected since the central portion does not have a considerably large anaerobic portion unlike a vinylidene chloride filler. Furthermore, since charcoal is not negatively charged, a large amount of suspended floc and suspended microorganisms cannot be attached and held to charcoal unlike a vinylidene chloride filler. Therefore, the above conventional technique (Japanese Patent Laid-Open Publication HEI 9-314163) does not have a remarkable effect on reduction of the generated sludge.
Another example of conventional techniques (Japanese Patent Laid-Open Publication HEI 10-314778) is described below. This conventional technique provides a waste-water treatment system wherein suspended solids are captured and removed and decomposition of organic matters by microorganisms can be sufficiently performed. Specifically, this system is constituted by an oxygen supply tank having a diffusing pipe installed at a bottom section thereof, a carrier attachment filter tank filled with fillers and a wash water discharge pump tank equipped with a wash water discharge pump. Furthermore, a diffusing pipe is installed at the bottom section of the carrier attachment filter tank and granular carriers as fillers are filled thereabove.
In this waste-water treatment system, suspended solids can be attached and removed or organic matters in waste water can be removed by microorganisms propagated on the packing material. However, since there is no anaerobic portion, digestion of attached suspended solids or propagated microorganisms (that is, reduction of generated sludge) cannot be expected. Furthermore, since a rapid filter is not installed after the carrier attachment filter tank, a sufficient measure is not taken when sludge exfoliates from the carrier attachment filter tank.
SUMMARY OF THE INVENTION
Accordingly, the object of the present invention is to provide a system and method for waste water treatment that can save energy and reduce waste.
In order to achieve the above object, there is provided a waste-water treatment system comprising an attachment filter having a packing material to which suspended solids are attached and a sedimentation section in a bottom section thereof, wherein
solids suspended in waste water are treated by sedimenting the solids attached to the packing material in the sedimentation section.
In the present invention, solids suspended in waste water are attached to the packing material in the attachment filter and then particle sizes are increased (particles are stacked to each other and are enlarged). Then, the solids attached in an anaerobic state are digested and reduced. Furthermore, sludge generated from the suspended solids is sedimented, separated and removed in the same attachment filter tank. In the present invention, since solids suspended in waste water can be treated by the attachment filter having a sedimentation section, solids suspended in waste water can be filtered without consuming a large amount of electrical energy. Furthermore, the generated sludge is sedimented in the sedimentation section and removed from this sedimentation section. Thus, waste water can be treated.
When microorganisms are attached and propagated on the packing material provided in the attachment filter, a function for decomposing organic matters is provided and the packing material itself has an attachment action. Therefore, a function for attaching solids suspended in waste water to this packing material for filtration is provided.
The above “attachment filter” means a filter wherein suspended solids such as a floc suspended in waste water or suspended microorganisms are attached and captured by a packing material carrying negative charges. The “attachment filter having a sedimentation section” means a device having both sedimenting and attaching functions.
In one embodiment of the present invention, the sedimentation section has a sludge collecting function for collecting sedimented sludge.
According to the above embodiment, the sedimentation section has a sludge collecting function. Therefore, after increase of particle sizes, specific gravity is changed by digestion and thereby sedimented sludge can be efficiently collected in the sedimentation section. Therefore, waste water in which a large amount of sludge is generated can also be treated by the sedimentation section having a sludge collecting function.
In one embodiment of the present invention, a rapid filter is installed in a subsequent stage of the attachment filter; and
solids
Chujo Kazumi
Yamasaki Kazuyuki
Hruskoci Peter A.
Nixon & Vanderhye P.C.
Sharp Kabushiki Kaisha
LandOfFree
System for waste water treatment capable of saving energy... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with System for waste water treatment capable of saving energy..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and System for waste water treatment capable of saving energy... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3276577