JPS6045924B2 - Sheep drum for sludge treatment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sieve drum suitable for dewatering sludge collected from a sewage treatment plant.

Conventionally, sludge collected from sewage treatment plants has a high water content and cannot be dumped, landfilled, or fermented as it is, so it is dehydrated.

However, this dewatering method involves adding a flocculant to the collected sludge with a high water content, feeding it into a flocculating mixing tank, then feeding it to a belt press type dehydrator, performing the desired dewatering process, and then dewatering the sludge. The cake is sent to the next process, and the wastewater discharged from the dehydrator is first led to a settling tank, and the supernatant water in which the sludge particles are precipitated is used as washing water for the dehydrator. In this method, the sludge is flocculated using a flocculant and then directly supplied to the dehydrator together with the dehydrated water for dehydration, resulting in poor dewatering efficiency and poor reuse efficiency of the dehydrated water as washing water. In view of this, the present invention proposes a ram under a sieve for sludge treatment that improves dewatering efficiency while efficiently reusing desorbed water. explain. In the figure, reference numeral 1 denotes a sieve drum body for treating sludge collected from a sewage treatment plant, etc. This sieve drum 1 for sludge treatment is arranged laterally as shown in the figure and rotatably supported by rollers 3 and the like. The inside of the sieve drum 1 is divided into a front stage IA and a rear stage IB, and a flocculation mixing tank 4 is provided in the front stage IA of the sieve drum. There are stirring blades 5 in the flocculation mixing tank 4, and a sludge supply pipe 2 is provided in front of the blades 5. The sludge, from which bulky waste and the like have been removed in advance, is mixed with a flocculating liquid using a static mixer or the like, and then supplied to the flocculation mixing tank 4 via the sludge supply pipe 2 by an appropriate transfer means. When the sieve drum rotates, the flocculation mixing tank integrated with the drum also rotates, so that the desired mixing and agitation is performed by the blades 5. Also, treated water, such as desorbed water from a dehydrator, is supplied to the J outer periphery of the flocculation mixing tank 4 via a water supply pipe 6, and is filtered at the front and rear outer peripheries of the sieve drum. Further, blades 7 are provided in the rear end of the sieve drum, and sludge sufficiently mixed with a flocculant is supplied to the front end of the sieve drum, where it is further mixed and agitated and primary dewatering is performed. The sludge after dewatering is sequentially discharged from the opening end of the sieve drum, and the desorbed water flows from the front and back stages of the sieve lower ram to a water collection chute 8 installed below the sieve drum.
It falls inside and is ejected. The outer peripheral surface of the sheave drum 1 is cleaned using a cleaning nozzle 9 placed above the sheave drum.
This is done using washing water that is spouted out. The sludge collected from sewage treatment plants, etc. is mixed in advance with flocculating liquid and supplied to the flocculation-mixing tank installed in the sieve drum, and inside the sieve drum, a dewatering machine is installed inside the outer periphery of this flocculation-mixing tank. The sludge is solidified in the rotating tank 4, solids in the waste water are filtered and removed by the ram under the sieve, and the desorbed water is passed through the sieve drum. Water is drained to separate solids and water, and clogging of the sieve drum is prevented by spraying cleaning water from a cleaning nozzle from above the outer periphery of the sieve drum.

The solid content of the sludge separated in this sieve drum is sent to the next step, a dehydrator, where it is further dehydrated and made to a desired moisture content and sent to the next step as a dehydrated cake for treatment. Separated water is temporarily stored in a tank and supplied by a pump to the nozzle for cleaning the ram under the sheave and the cleaning nozzle for cleaning cloth in the dehydrator for use as cleaning water. In addition, dehydrated water dehydrated using a dehydrator or the like is also supplied into the sieve drum by a pump. In addition, wastewater from a dehydrator or the like may be directly supplied to a passage provided in the sieve drum. According to the present invention, the sieve drum is divided into front and rear parts, and a coagulation mixing tank is provided in the front stage, so the flocculant is mixed with the sludge and supplied, and the sludge is thoroughly mixed and agitated in this tank, and is coagulated. Also the treated water supplied to the tank? overprocessed,
Moreover, since the coagulated sludge is further dewatered in the latter part of the drum, the sludge and desorbed water are separated and discharged, which simplifies the treatment in the next process and also simplifies the construction of the sieve drum. It has the advantage of having a simple structure and being able to be provided at low cost.

[Brief explanation of the drawing]

FIG. 1 is an external view, and FIG. 2 is a sectional view. 1... Sieve drum, 2... Sludge supply pipe, 3... Roller, 4... Coagulation mixing tank, 5...
...Blade, 6...Water pipe, 7...Blade, 8
...Water collection chute, 9...Washing nozzle.

Claims (1)

[Claims] 1 A sheave drum rotatably supported opposite the outer circumferential surface cleaning nozzle is divided into two stages, front and rear, and a flocculation mixing tank equipped with stirring blades is arranged in the front stage, and from the front part of this coagulation mixing tank, The sludge is supplied and the sludge is discharged from the rear of the sieve drum to the rear stage of the sieve drum, and the treated water is supplied between the coagulation mixing tank and the front stage of the sieve drum and is filtered at the front stage of the sieve drum. A sieve drum for sludge treatment featuring: