JPH0474600A - Treatment of dehydrated sludge, vegetable residue and food residue - Google Patents

Abstract

PURPOSE:To efficiently dry dehydrated sludge and residue by a method wherein dehydrated sludge generated by drainage treatment, vegetable residue and food residue are mixed to be charged in a pressure boiler and subsequently heated under stirring in a vacuum state. CONSTITUTION:Several pipe supports 23 having heating pipes 24 horizontally provided to the end parts thereof in parallel to the axis of a revolving cylinder 15 and arm pipes 26 having stirring blades 25 fixed to the end parts thereof are radially provided to the periphery of the revolving cylinder 15 and connected to a steam pipe along with the jacket part 33 in an outer body 1. Dehydrated sludge generated by drainage treatment, vegetable residue and food residue are mixed to be charged in an inner body 2 from a charging port 3 and, after a pressure boiler is brought to a vacuum state, the obtained mixture is heated under stirring to form mixed granules. At this time, residues enter the spaces between particles of the dehydrated cake to generate gaps and the dehydrated cake is not solidified in a dumpling state and can be internally dried. Further, it is prevented that residues are bonded to the wall surface of the inner body in a thin scorched state and heat can efficiently be conducted to the wall surface of the inner body.

Description

Detailed Description of the Invention (Industrial Field of Application) This invention provides a method for storing food in a pressure can having a cylindrical outer shell shape, which is configured to allow heated steam to flow from the outside, and is provided with an inner shell. Dehydrated sludge generated by wastewater treatment at a processing factory, etc., and vegetable residue and food residue discharged during the food processing process at a food processing factory, etc. are mixed and added, and the mixture is further heated and stirred. By vacuum-drying the mixture, a mixed granular material of dehydrated sludge, vegetable residue, and food residue is formed, so that dehydrated sludge, vegetable residue, and food residue, which contribute to pollution, can be efficiently treated. This invention relates to a new method for treating dehydrated sludge, vegetable residue, and food residue.

(Prior Art) Conventionally, the applicant of the present application developed a device for separating and recovering residues from marine product processing and activated organic sludge by steaming and obtaining useful organic oil, feed, fertilizer, etc.
There is a device with patent rights as No. 80.

This device is a jacket mechanism that has an inner shell inside a cylindrical outer shell, and the upper part of the outer shell is equipped with an inlet that connects to the inner shell from the outside, an exhaust valve for evaporated steam, and a trachea that leads to the air suction device. In addition, a plurality of exhaust pipes communicating with the inner cavity were attached to the side of the outer body, and an outlet was provided in the lower part of the outer body.

In such devices, heated steam is passed from the outside into the outer shell, and the stirring blades and steam are passed through a rotary cylinder that is rotatably attached to a hollow shaft that passes the steam into the inner shell. It is designed to agitate the inside of the inner shell by connecting and rotating heating pipes, perform indirect heating by maintaining the temperature inside the inner shell at approximately 120 to 130°C, and perform drying by applying radiant heating to residue and sludge. was.

Further, the oil content of the heated and dried ingredients is discharged from the upper discharge pipe, and the water content is discharged from the middle and lower discharge pipes, and the residue and muddy semi-solids are further steamed. The solid material was then vacuum dried and taken out from the outlet as a solid.

Furthermore, conventionally, in food processing factories, etc., activated sludge method is used to biologically treat sewage by mixing and stirring sewage discharged from the factory and activated sludge, and supplying oxygen by blowing air into the mixed mixture. Wastewater treatment is carried out by
Furthermore, in the food processing process, vegetable residues such as vegetable scraps and food residues such as gyoza skins are inevitably discharged at the stage of food processing.

(Problems to be Solved by the Invention) However, even when wastewater treatment is carried out using the conventional activated sludge method described above, the precipitated sludge remains as dehydrated sludge at the final stage of the treatment, and the treatment of the dehydrated sludge There was a problem in that it required .

In addition, in food processing factories, etc., vegetable residues such as vegetable scraps and food residues such as dumpling skins are inevitably discharged during the food processing stage, and these vegetable residues and food residues are There was a problem with the need to process things.

In particular, due to the abnormal increase in the amount of waste generated in recent years, there is an extreme shortage of industrial waste treatment plants, and as a result, there are no final disposal sites where the dehydrated sludge, vegetable residue, and food residue can be directly disposed of. There was a problem that there was a shortage and it would not be possible to dump these industrial wastes in the near future.

Furthermore, if the dehydrated sludge is vacuum-dried alone using the device patented by the applicant, the grain shapes between the dehydrated sludge become compact under vacuum conditions, resulting in dewatering. There was a problem in that the sludge formed lump-like lumps with each other and internal drying was impossible, making it impossible to dry the dehydrated sludge.

Furthermore, when the vegetable residues and food residues are vacuum-dried alone using the device patented by the applicant, the heating pipe reduces the internal temperature to approximately 120 to 130 degrees. Vegetable residues and food residues come into contact with the inner shell wall surface which is maintained at ℃.

In this way, when vegetable residues and food residues come into contact with the high-temperature inner wall surface, the inner wall surface becomes abnormally heated due to the viscosity of the vegetables, and vegetable residues form a thin burnt shape on the inner wall surface. Also, there was a problem that food residues adhered to the product.

In particular, in a vacuum state, there is no convection, so the only way to do this is to maintain the temperature inside the inner shell through heat conduction through the inner shell wall, thereby performing indirect heating and drying. There was a problem in that the heat transfer efficiency was extremely reduced due to the attachment of vegetable residues and food residues in a thin burnt shape, making it impossible to perform sufficient drying.

The present invention was developed in order to solve the above-mentioned conventional problems, and is a novel sludge system that efficiently processes dehydrated sludge, vegetable residues, and food residues that contribute to pollution. A method for treating residue and food residue is provided.

(Means for Solving the Problem) In order to achieve the above object, the present invention provides
After the dehydrated sludge produced by wastewater treatment, vegetable residue, and food residue are mixed and input, the inside of the pressure can is vacuumed, and then the mixture of the dehydrated sludge, vegetable residue, and food residue is heated and stirred. By doing this, mixed granules can be formed and dehydration can be easily carried out.

A method for treating mud, vegetable residues and food residues is provided.

(Function) As described above, in the present invention, since the mixture of dehydrated sludge, vegetable residue, and food residue is heated and stirred under a vacuum condition, the vegetable residue is formed into particles between the dehydrated sludge. The presence of these voids prevents the dehydrated sludge from forming lump-like lumps with each other, which enables internal drying and separates the dehydrated sludge, vegetable residue, and food residue. You can easily dry things.

In addition, as mentioned above, vegetable residues and food residues enter the grains between the dehydrated sludge, resulting in the vegetable residues and food residues adhering to the inner shell wall surface in a thin square shape. Therefore, heat conduction can be efficiently conducted to the inner shell wall surface, and drying can be performed by indirect heating while keeping the temperature of the inner shell constant (Example) Examples of the present invention will be described in detail below. do.

In this example, after dehydrated sludge produced by wastewater treatment, vegetable residue, and food residue are mixed and charged into the pressure end, the inside of the pressure end is made into a vacuum state, and then the dehydrated sludge, vegetable residue, and This is a method for treating dehydrated sludge, vegetable residues, and food residues by heating and stirring a mixture of food residues to form mixed granules.

As shown in Fig. 1, the pressure iron has a horizontally installed cylindrical outer shell 1.
It is a double evaporation can with a jacket part 33 and an inner shell 2 provided with a gap inside thereof, and a charging port 3 communicating from the outside into the inner shell 2 is formed in the upper part of the can.

Outside, there is a raw material hopper containing dehydrated sludge and a raw material hopper containing vegetable residue and food residue.The dehydrated sludge, vegetable residue and food residue supplied from these two raw material hoppers are , are mixed by a screw conveyor and charged into the inner shell 2 from the feed port 3.

A hollow shaft 17 that communicates with the inside of the rotating cylinder is fixed to the rotating cylinder 15. Furthermore, the end of this hollow shaft 17 is connected to a steam pipe, and the rotating hollow shaft 17 is connected to the rotating cylinder. 15 so that steam can enter.

Furthermore, a discharge pipe 39 for discharging used steam in the rotating cylinder is passed through the inside of the hollow shaft 17, and extends from the pump to a drain.

Several front widths 23 are attached radially around the rotating tube 15, and a heating pipe 24 is horizontally suspended at the end thereof parallel to the axis.

The front width 23 and the heating pipe are communicated with the rotary cylinder 15, and are configured to stir and heat the inside of the inner shell 2.

A stirring blade 25 is fixed to the end of the rotary tube 15 at a position shifted from the front width 23, and arm tubes 26 communicating with the rotary tube 15 are radially attached.

A steam pipe 31 branched from the main steam pipe through which steam at 100°C to 150°C flows communicates with a jacket part 33 in the outer shell 1, and keeps the temperature inside the inner shell 2 at about 120°C to 130°C.
It is configured to be maintained at ℃ and heated indirectly.

In this example, after dehydrated sludge produced by wastewater treatment, vegetable residue, and food residue are mixed and input into the pressure end configured as described above, the inside of the pressure end is brought into a vacuum state,
Thereafter, the mixture of the dehydrated sludge, vegetable residues, and food residues is heated and stirred to form mixed granules, and the dehydrated sludge, vegetable residues, and food residues are treated. .

In addition, as an example of the dry state, 1 cubic of dehydrated sludge is mixed with 1 cubic of vegetable residue and food residue, and the mixture is put into the pressure end to create a vacuum state, and then the dehydrated sludge and vegetable residue are mixed. When the mixture of dehydrated sludge, vegetable residue, and food residue was heated and stirred for 5 hours, the mixture of dehydrated sludge with a moisture content of 85%, vegetable residue, and food residue became mixed granules with a moisture content of 5%. could be compressed and dried.

In addition, by adding various additives, etc. during the treatment process, it can be used as a heat source to promote combustion and incineration, and can be applied to the production of feed and fertilizer, and furthermore, it is possible to finish uniform mixing in the equipment. It is possible to generate advantages that can be achieved.

(Effects of the Invention) As explained above, the method for treating dehydrated sludge, vegetable residue, and food residue of the present invention has the following effects.

■In this invention, since the mixture of dehydrated sludge, vegetable residues, and food residues is heated and stirred under vacuum conditions, the vegetable residues and food residues get into the grains between the dehydrated sludge. Voids are created, and the presence of these cavities prevents the dehydrated sludge from forming lump-like lumps together, which enables internal drying and allows drying of dehydrated sludge, vegetable residues, and food residues. is possible,
It has the excellent effect of allowing industrial waste to be easily compressed and dried.

■Also, since vegetable residues and food residues will enter the granules between the dehydrated sludge, it is possible to prevent vegetable residues and food residues from adhering to the inner barrel wall in a thin scorch-like form. It has the excellent effect that heat can be efficiently conducted to the inner shell wall surface, and drying can be easily performed by indirect heating while keeping the temperature inside the inner shell constant.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway cross-sectional view of the outer shell, inner shell, and rotating cylinder. 1...Outer shell, 2...Inner shell, 1-5...Rotating cylinder, 2
3...Front width, 24...Heating pipe. Patent applicant: Kangaki Iron Works Co., Ltd. Engraving of the drawings (no changes to the content) No. 1 Amendment to drawing procedures (issued) August 21, 1990

Claims (1)

[Claims] (1) After mixing dehydrated sludge, vegetable residue, and food residue produced by wastewater treatment into a pressure can, the inside of the pressure can is vacuumed, and then the dehydrated sludge, vegetable residue, and food residue are mixed together. 1. A method for treating dehydrated sludge, vegetable residue, and food residue, characterized in that a mixed granular substance is formed by heating and stirring a mixture of substances.