JP2007147245A - Promotion method of dehydration and drying of hydrous granule and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To dehydrate or dry hydrous granule efficiently and at a low cost. <P>SOLUTION: Migration resistance of water is decreased, speed of dehydration or drying is increased, a dehydrate ratio is improved and a processing cost is reduced by adding an ultrasonic action to a dehydrating or drying process of the hydrous granule. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and apparatus for dehydration and drying of water-containing granular materials, and more particularly to a method and apparatus for dewatering or drying sludge, industrial residues, and industrial water-containing granular materials generated in wastewater treatment.

  In various industrial activities, there are many cases where large amounts of particulate semi-finished products or residues with high water content are generated, and it is necessary to reduce the water content in order to make semi-finished products into products or to treat residues. . Therefore, dehydration or drying operations are often used. In particular, biological methods are widely used for the treatment of wastewater containing organic pollutants. During this wastewater purification process, a large amount of sludge is discharged outside the facility. Since this drainage sludge has a high water content and is prone to spoilage, it must be detoxified immediately, and dehydration or drying is indispensable.

  It is well known that dehydration or drying is energy consuming and expensive. In particular, in the case of a substance having a large water movement resistance in the particle, a substance having a large particle, and a non-dehydrating substance, the resistance of moisture to move from the inside of the particle to the outside is high, the drying speed is slow, and the drying time is long. Cost is high. For example, malt residues from beer manufacture, fermentation cells, waste sludge, etc., have high water transfer resistance and are difficult to dehydrate and dry during dehydration and drying, resulting in high processing costs.

  In existing technology, pressing or heat drying is often used, but the current situation is that the processing is performed at high cost. In addition, transportation costs are high due to high water content. If the resistance to move moisture from the inside to the outside of the particles can be reduced, a low moisture content can be achieved even in the dehydration operation, the drying speed can be increased, the drying time can be shortened, and the processing cost can be reduced. There is a need for a method that can realize dehydration and drying of these substances at low cost and with stable operation.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a method and an apparatus that can be stably operated efficiently, at low cost, and can promote dehydration and drying of water-containing granular materials with a reliable effect. And

Means for Solving the Invention

  The invention according to claim 1 adds an ultrasonic action step for applying ultrasonic waves to the water-containing granular material before and after the dehydration or drying or dehydration and drying steps in the treatment process for reducing the water content of the water-containing granular material. This is a method for promoting dehydration or drying of a water-containing granular material. By applying ultrasonic waves to the water-containing particulate matter, the capillary-bound water and the surface-attached water of the particulate matter are moved out of the particulate matter, and at the same time, the particulate wall of the particulate matter, for example, the cell wall of the cell is destroyed and the internal water is removed Can be moved to. By these effects, the speed of dehydration and drying can be increased to increase the dehydration rate of the granular material, and at the same time, it can be effectively dried even with hot air having a relatively low temperature.

  The invention described in claim 2 is characterized in that the excess sludge generated in the biological treatment process of the waste water is agglomerated and sent to the dehydration process after ultrasonic waves are applied to the concentrated agglomerated sludge obtained by concentration. This is a method for promoting dewatering of wastewater sludge. The action of this ultrasonic wave breaks the cell wall and makes it easier to move the internal water to the outside, increasing the dewatering rate and increasing the sludge dewatering rate.

  The invention according to claim 3 aggregates and concentrates the excess sludge generated in the biological treatment of the wastewater, and further sends ultrasonic waves to the dewatered sludge obtained in the dewatering step and then sends it to the next dewatering step. Is a method for promoting the dewatering of wastewater sludge. It becomes difficult to dehydrate the coagulated sludge by pressure or centrifugal force after removing water that is easy to dehydrate in the dehydration step. In this case, the water in the inner layer of sludge dehydrated by the action of ultrasonic waves is moved to the outer layer, or the resistance to move the internal water to the outside by destroying the cell wall is further reduced. Then, the dehydration rate can be increased and at the same time the dehydration rate can be increased.

  In the invention according to claim 4, after the surplus sludge according to claim 2 or 3 is subjected to the ultrasonic action step and the dehydration step, at least the ultrasonic action step and the dehydration step, or the ultrasonic action step. And a drying step, or an ultrasonic action step, a dehydration step, a drying step, or a drying step, or a method for promoting dehydration or drying of wastewater sludge. When the sludge dehydrated after receiving the ultrasonic action in this way still has a high moisture content, the moisture content can be lowered efficiently by passing through these steps.

  The invention according to claim 5 is characterized by aggregating and concentrating surplus sludge generated in the biological treatment of waste water, sending ultrasonic waves to the dewatered sludge obtained in the dewatering step, and then sending it to the drying step. This is a method for promoting the drying of wastewater sludge. By further applying ultrasonic waves to the dehydrated sludge obtained in the dehydration step, the cell wall can be destroyed, or the water in the inner layer of the sludge can be moved to the outer layer, thereby increasing the drying rate. In particular, it becomes possible to quickly dry even hot air having a low temperature by reducing the resistance to movement of water.

  The invention according to claim 6 is characterized in that an ultrasonic action step and a dehydration step or an ultrasonic action step and a drying step, or a combination thereof are added after dehydration of the water-containing residue discharged from industrial activities in the dehydration step. This is a method for promoting dehydration or drying of the water-containing granular material. In the manufacturing industry, it is often difficult to lower the water-containing residue discharged after reducing the water content to some extent in a dehydration process such as pressing. In this case, when the action of ultrasonic waves is applied, the adsorbed water or the internal water of the particles can be moved to the outside. Moreover, since the movement resistance of water can be lowered by causing a change in the original structure of the particles, the effect of further dehydration and drying can be enhanced.

  The invention according to claim 7 is a method for promoting dehydration of hydrous particulates, wherein the dehydration action and ultrasonic action are simultaneously applied to the hydrous granule in the hydrous granule dehydration step. When the water content is relatively low and when dehydration is difficult, if the ultrasonic particles and dehydration are simultaneously applied to the water-containing granular material, the dehydration effect can be greatly enhanced by the synergistic effect.

  The invention according to claim 8 is the claim for promoting dehydration or drying of water-containing granular material using ultrasonic waves provided with at least an ultrasonic generator, an ultrasonic working phone, and a granular material shipping mechanism for feeding the water-containing granular material. The ultrasonic action device according to Items 1 to 7. With this apparatus, it is possible to cause ultrasonic waves to act on the water-containing granular material, and the water-containing granular material can be efficiently dehydrated and dried. In actual cases, the structure of the hydrated product and the machine are different, but these parts are essential basic parts, and the other attached parts may be optimized based on the actual situation in the field.

  The water-containing granular material refers to a mixture in which a particulate solid and water are mixed. The particle shape may be any size and shape. In addition, those containing water penetrating into the solid body are also water-containing granular materials.

  The above-mentioned surplus sludge is not only a normal academic surplus sludge, that is, biological sludge discharged from the final sedimentation basin of the wastewater treatment plant, but also mixed sludge, digested sludge, Some types of sludge are also included. In the present invention, it is abbreviated as excess sludge for simplification.

The invention's effect

  According to the present invention, the dehydration rate and dehydration rate of the water-containing granular material can be increased at a low cost and with high efficiency. Similarly, the drying rate of the water-containing granular material can be increased, and in particular, a heat source having a relatively low temperature can be efficiently used. In addition, in order to improve the dehydration rate, the load of moisture removal by drying can be reduced, leading to energy saving. These effects enable low-cost processing.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not restrict | limited by this Example.

  It is one of the Example of the dehydration promotion method of the wastewater treatment sludge of this invention. A flocculant is added to the mixed sludge discharged from the wastewater treatment plant, ultrasonic waves are applied to the concentrated sludge that has been coagulated and precipitated, and then dehydrated using a press dehydrator, and then dried sludge is obtained in the drying step.

  It is one of the Examples of the waste water treatment sludge which concerns on this invention. A flocculant is added to the mixed sludge discharged from the wastewater treatment plant, and the concentrated sludge that has been coagulated and precipitated is dehydrated using a belt press dehydrator. A dehydrated sludge cake of 66% or less is obtained.

  It is one of the Examples of the waste water treatment sludge which concerns on this invention. It was obtained by adding a flocculant to the mixed sludge discharged from the wastewater treatment plant, dewatering the condensed sludge coagulated and precipitated using a belt press dehydrator, then applying ultrasonic waves, and further dehydrating with a dehydrator The sludge cake with a low water content is dried with hot air at 60 to 150 ° C. in the drying step to obtain a dry sludge with a water content of 15 to 30%, which is used as a fuel.

  It was obtained by adding a flocculant to the mixed sludge discharged from the wastewater treatment plant, dewatering the condensed sludge coagulated and precipitated using a belt press dehydrator, then applying ultrasonic waves, and further dehydrating with a dehydrator The sludge cake having a low water content is dried using hot air in the drying process to obtain a dry sludge having a water content of 55% or less and incinerated.

  The malt residue in the beer manufacturing process or other food manufacturing residue is dehydrated with a press or a belt press, and then ultrasonically acts on the dehydrated residue to obtain a low moisture content residue with a dehydrator and sent to the drying process. Dried to obtain a dry residue.

  The fermented residue generated in the production of fermented foods or pharmaceuticals is dehydrated with a squeezing machine or a belt press, and after applying ultrasonic waves to the obtained dehydrated residue, it is again sent to the dehydration process for further dehydration and low water content To rate residue. The obtained low water content residue is sent to a drying step and dried to obtain a dry residue.

  It is one of the Example of the basic structure part and operating method of the ultrasonic action apparatus based on this invention. The water-containing granular material is fed into the ultrasonic action cell equipped with the ultrasonic action phone connected to the ultrasonic generator by the screw mailer, moved forward while receiving the action of the ultrasonic wave, and discharged from the action cell.

Claims (8)

In the treatment process for reducing the moisture content of the water-containing granular material, an ultrasonic action step for applying ultrasonic waves to the water-containing granular material is added before or after dehydration or drying or dehydration and drying steps. Method for promoting dehydration or drying A method for accelerating dewatering of wastewater sludge, characterized by coagulating and concentrating surplus sludge generated during biological treatment of wastewater and applying ultrasonic waves to the concentrated agglomerated sludge obtained by sending it to a dewatering step for dehydration. Promoting dewatering of wastewater sludge, characterized by agglomerating and concentrating surplus sludge generated during biological treatment of wastewater, and then applying ultrasonic waves to the dewatered sludge obtained in the dewatering process before sending it to the next dewatering process Method. After the surplus sludge according to claim 2 or 3 is subjected to an ultrasonic action step and a dehydration step, at least an ultrasonic action step and a dehydration step, or an ultrasonic action step and a drying step, or an ultrasonic action step. And a dehydration step and a drying step, or a method for promoting dewatering or drying of wastewater sludge, which is sent to a drying step. A method for promoting drainage sludge drying, comprising aggregating and concentrating surplus sludge generated in biological treatment of wastewater and applying ultrasonic waves to the dewatered sludge obtained in the dewatering step and then sending it to the drying step. Dehydration or drying of water-containing granular materials characterized by adding an ultrasonic action process and a dehydration process, an ultrasonic action process and a drying process, or a combination thereof after dehydrating water-containing residues discharged from industrial activities in the dehydration process How to promote. A method for accelerating dehydration of water-containing granular materials, wherein a dehydrating action and an ultrasonic action are simultaneously applied to the water-containing granular materials in the step of dehydrating the water-containing granular materials. The ultrasonic action according to any one of claims 1 to 7 for promoting dehydration or drying of water-containing granular material using ultrasonic waves provided with at least an ultrasonic generator, an ultrasonic working phone, and a granular material shipping mechanism for feeding the water-containing granular material. apparatus.