JP2009133518A - Method and system for producing fuel from waste sludge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently produce fuel from waste sludge such as waste coating materia sludge at low costs as a fuel for combustion furnace such as cement baking furnace. <P>SOLUTION: This waste sludge fuel production system 1 comprises a mixing device 4 for mixing the waste sludge S and liquid fuel L, first supplying device 3, 7 for supplying the waste sludge to the mixing device, second supplying devices 8, 10 for supplying the liquid fuel to the mixing device, a crushing device 6 for crushing the mixture M mixed by the mixing device, and third supplying devices 9, 11 for introducing the crushed material C crushed by the crushing device to a combustion furnace 20. The waste sludge and the liquid fuel are mixed, the mixture obtained by the mixing is crushed, and the crushed material obtained by crushing is introduced to the combustion furnace to be burned. The first supplying devices comprise a piston pump and a supply pipe inserted to an inner part of the mixing device, and preferably comprise a dispersion plate 7a for dispersing the waste sludge when the waste sludge is supplied to an end portion of the supply pipe. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and a system for fuelizing waste sludge, and more particularly to a method and a system for fuelizing highly viscous waste sludge such as waste paint sludge as fuel for a combustion furnace such as a cement firing furnace.

  Conventionally, attempts have been made to reduce the basic unit of expensive fossil fuels in cement production while using various wastes as substitutes for fuel in the cement production process, contributing to waste disposal. For example, in Patent Document 1, waste plastic and waste oil are mixed, and the slurry mixture is fed to an auxiliary fuel burner inserted in the center of a main fuel (pulverized coal) burner of a rotary kiln to assist the auxiliary fuel burner. A method of manufacturing a cement clinker that is blown into a rotary kiln from a fuel outlet and burned has been proposed.

  On the other hand, in recent years, waste sludge such as waste paint sludge, waste solvent distillation residue, waste grease, oil sludge, waste ink and waste white clay has been incinerated, but not simply incineration to suppress CO. Therefore, there is a demand for thermal recycling such as fuel that effectively uses the amount of heat generated. Waste sludge generally refers to organic precipitates generated when sludge, sewage treatment, factory wastewater treatment, etc., but in this specification, solids are mixed in the liquid. Waste or waste consisting of high viscosity, partially or wholly, is flammable. This waste sludge is highly viscous and contains large lumps, making it difficult to handle and causing problems such as clogging of the supply pipe when supplying to a cement firing furnace, etc. In many cases, it is difficult to substitute for fuel.

  By the way, in Patent Document 2, various crushed wastes are kneaded with a mixer to form high-viscosity wastes, which are accommodated in a viscosity modifier tank according to the viscosity of the high-viscosity wastes in the mixer. Waste liquid sludge as a viscosity modifier is individually supplied into the mixer, and after adjusting the viscosity of the high-viscosity waste in the mixer to a state suitable for pump pumping, a device that pumps and burns it to the firing furnace with a pump, etc. Proposed.

  Patent Document 3 also discloses a waste stream fuel composition containing liquid, non-aqueous components, solid components and aqueous components such as refined waste, waste from aluminum refining processes, paint waste and other industrial waste. A technique for converting an object into fuel is disclosed.

JP 2003-192406 A Japanese Patent No. 3846254 JP 2002-536493 A

  When various types of waste are fired in a cement firing furnace using the apparatus described in Patent Document 2, there is an advantage that a plurality of types of waste can be treated at the same time. Since it is necessary to crush, crush the crushed waste, and add a viscosity modifier according to the viscosity of the waste, the processing equipment becomes large and equipment and operating costs increase. .

  Also, in the fueling method described in Patent Document 3, since a ball mill is used to obtain a liquid material sufficient to pulverize a bulk solid contained in industrial waste and enable pumping, the apparatus and operation There was a problem that the cost increased.

  Therefore, the present invention has been made in view of the above-described problems in the prior art, and efficiently converts waste sludge such as waste paint sludge as fuel for a combustion furnace such as a cement firing furnace at low cost. For the purpose.

  In order to achieve the above object, the present invention is a method for converting waste sludge into fuel, which comprises mixing waste sludge and liquid fuel, crushing the mixture obtained by the mixing, and crushing material obtained by the crushing Is introduced into a combustion furnace and burned in the combustion furnace.

  According to the present invention, since the waste sludge and the liquid fuel are mixed, even when the viscosity of the received waste sludge is high, the viscosity can be lowered by mixing with the liquid fuel, and the properties are homogenized and handled. Therefore, waste sludge can be easily converted into fuel. Moreover, since it is not necessary to pre-process waste sludge using a viscosity modifier etc. in the case of fuel conversion, an operating cost can also be reduced. Furthermore, since the mixture is crushed and then introduced into the combustion furnace, it is easy to supply to the combustion furnace even when a lump of waste sludge is mixed, and the properties of the mixture of waste sludge and liquid fuel Is more homogenized, and when introduced into the combustion furnace, the influence on the combustion state of the combustion furnace can be minimized. In addition, by using waste sludge as a fuel alternative, it becomes possible to reduce the basic unit of expensive fossil fuel.

  In the fuel conversion method for waste sludge, the waste sludge can be at least one selected from the group consisting of waste paint sludge, waste solvent distillation residue, waste grease, oil sludge, waste ink, and waste white clay.

  Moreover, in the method for converting waste sludge into fuel, the liquid fuel may be at least one selected from the group consisting of waste solvent, waste oil, waste paint, emulsion fuel, and organic substance-containing waste liquid. Thereby, not only waste sludge but also waste solvent can be converted into fuel at the same time.

  In the waste sludge fuelization method, the crushed material can be introduced from one or more locations selected from the group consisting of a kiln front part, a kiln bottom part, and a calcining furnace of a cement kiln. As a result, the basic unit of expensive fossil fuel necessary for producing cement can be reduced, and the ash contained in the waste sludge can be used as a cement raw material, so that no waste is generated. .

  The present invention is also a waste sludge fueling system, a mixing device that mixes waste sludge and liquid fuel, a first supply device that supplies waste sludge to the mixing device, and the liquid fuel that is mixed A second supply device for supplying to the device, a crushing device for crushing the mixture mixed by the mixing device, and a third supply device for introducing the crushed material crushed by the crushing device into a combustion furnace. It is characterized by.

  According to the present invention, as in the case of the above-described invention, waste sludge can be easily converted into fuel while keeping operating costs low, and the influence on the combustion state of the combustion furnace is minimized when introduced into the combustion furnace. This makes it possible to reduce the basic unit of expensive fossil fuel. Further, since the fueling system is configured with a simple device configuration, it is possible to avoid an increase in device cost.

  In the waste sludge fuelization system, the first supply device may be configured to include a piston pump, a twin screw pump, a mono pump, or a rotary pump. Since the piston pump or the twin screw pump can transport sludge containing a relatively large lump, it can be easily conveyed even when lump is contained in the mixture of waste sludge and liquid fuel. When the sludge contains no lump, it can be configured to include a mono pump or a rotary pump.

  In the waste sludge fueling system, the first supply device is provided with a supply pipe inserted to the inside of the mixing device, and the waste sludge is supplied to the supply pipe at an end portion on the mixing device side. In this case, a dispersion plate for dispersing the waste sludge can be provided. Thereby, when supplying waste sludge, while being able to prevent clogging in a supply pipe, mixing with liquid fuel in a mixing device can be performed more effectively.

  As described above, according to the present invention, waste sludge such as waste paint sludge can be efficiently converted into fuel as a fuel for a combustion furnace such as a cement firing furnace at low cost.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows an embodiment of a waste sludge fueling system according to the present invention. This fueling system 1 is roughly divided into a piston pump 3, a premix tank 4, a liquid fuel tank 5, and a crusher. 6 and a slurry pump 9 or the like. In the following description, the fueling system 1 is applied to a cement kiln 21 as an example of a combustion furnace.

  The piston pump 3 is provided for supplying waste sludge such as waste paint sludge received via the receiving hopper 2 to the premix tank 4. The piston pump 3 is provided with a wide frontage so as to be able to supply large lumps mixed in the waste sludge, and conveys the waste sludge to the premix tank 4 via the supply pipe 7. The supply pipe 7 includes a dispersion plate 7a for dispersing the waste sludge at the end on the premix tank 4 side. In addition, it can replace with piston pump 3 and can also use a twin screw pump, and when a lump is not contained in waste sludge, it can replace with these pumps and can also use a Mono pump or a rotary pump. .

  The liquid fuel tank 5 is generally used for temporarily storing liquid fuel, and stores a waste solvent or the like as the liquid fuel. In the following description, a waste solvent is used as the liquid fuel.

  The premix tank 4 is provided to mix waste sludge conveyed from the piston pump 3 and waste solvent supplied from the liquid fuel tank 5. At the bottom of the premix tank 4, a high-speed stirrer 4a that is supported by a rotating shaft and rotates in a horizontal plane and stirs both to promote mixing is disposed. Near the bottom of the premix tank 4, one end of a transport pipe 11 for transporting a mixture of waste sludge and waste solvent (hereinafter abbreviated as “mixture”) to the crusher 6 is located. Is provided with a discharge pipe 12 and a valve 13 for discharging foreign matters staying at the bottom of the premix tank 4 to the outside.

  The crusher 6 is provided for crushing the mixture supplied from the premix tank 4, and includes, for example, a rotor / stator type high shear mixer manufactured by Silverson, a trigonal as an in-line wet medialess pulverizer, A monopump Muncher or the like can be used.

  Next, operation | movement of the waste sludge fueling system 1 which has the said structure is demonstrated, referring FIG.

  The received waste sludge S is put into the receiving hopper 2 and the received waste solvent L is stored in the liquid fuel tank 5. During the operation of the cement burning equipment 20, the waste sludge S is extracted from the receiving hopper 2 and supplied to the premix tank 4 through the supply pipe 7 by the piston pump 3, and the waste solvent L is supplied through the supply pipe 10 by the pump 8. The premix tank 4 is supplied.

  As described above, the waste sludge S includes high-viscosity objects, large lumps, and the like, but can be easily transported to the premix tank 4 by the piston pump 3 having a wide frontage. Further, the waste sludge is supplied to the premixing tank 4 while being dispersed by the dispersion plate 7a provided at the tip of the supply pipe 7, thereby preventing clogging of the waste sludge in the supply pipe 7 and preliminarily removing the waste sludge. It can be dispersed in the mixing tank 4, and the mixing efficiency with the waste solvent L in the premixing tank 4 can be increased.

  In the premix tank 4, the waste sludge S and the waste solvent L are mixed using a high-speed stirrer 4 a and the like, and the mixture M obtained by this mixing is supplied to the crusher 6 through the supply pipe 11. Even when the viscosity of the received waste sludge S is high, the viscosity can be lowered by mixing with the waste solvent L, and the properties are homogenized, so that subsequent handling becomes easy. Foreign matter such as metal deposited on the bottom of the premix tank 4 is periodically discharged through the discharge pipe 12 and the valve.

  The mixture M is crushed in the crusher 6, and the obtained crushed material C is blown into the cement kiln 21 from the burner 23 via the slurry pump 9 and used for cement firing. Even when a lump of waste is mixed in the received waste sludge S, the lump is broken finely by crushing the mixture M, and is easily blown into the cement kiln 21. As described above, the waste sludge S and the waste solvent L can be used as a fuel substitute in the cement firing step.

  In the waste sludge fueling system 1, the waste solvent L is supplied to the supply pipe 11 via the valve 14 located below the liquid fuel tank 5, and the waste solvent L is singly supplied to the cement kiln 21 via the slurry pump 9. The waste solvent L can be further added to the crushed material C produced by the crusher 6 using the valve 14 and can be blown into the cement kiln 21 via the slurry pump 9.

  Since the waste sludge fueling system 1 having the above-described configuration includes the premix tank 4, the mixture M of the waste sludge S and the waste solvent L can be obtained, and the supply system of the waste sludge S or the supply of the waste solvent L can be obtained. Even when a problem occurs in the system, there is an advantage that the supply of the crushed material C is not immediately disturbed and the quality fluctuation of the crushed material C supplied to the cement kiln 21 is small. In particular, by making the premix tank 4 large-scale, the above effect is enhanced.

  Further, even if the waste sludge S is highly viscous, the waste sludge fueling system 1 stops the piston pump 3 and operates for a predetermined time while the supply of the waste sludge S is stopped. Since the waste sludge is washed away and the waste sludge does not adhere to the inside of the transport pipe 11, the waste sludge can be efficiently converted into fuel.

  In the above-described embodiment, the case where the crushed material C is supplied to the cement kiln 21 from the front side of the kiln and used as fuel has been described. However, the crushed material C can be introduced from the kiln bottom of the cement kiln 21. It can also be introduced from a calciner attached to the kiln 21 and used as fuel.

  Moreover, in the said embodiment, although the case where the waste sludge fueling system 1 concerning this invention was applied to the cement kiln 21 was illustrated, this fueling system 1 is not restricted to the cement kiln 21 but various combustion furnaces. Can be applied to.

1 is an overall schematic diagram showing an embodiment of a waste sludge fueling system according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Waste sludge fuel conversion system 2 Receiving hopper 3 Piston pump 4 Premix tank 4a High speed agitator 5 Liquid fuel tank 6 Crusher 7 Supply pipe 7a Dispersion plate 8 Pump 9 Slurry pump 10 Supply pipe 11 Transport pipe 12 Discharge pipe 13 Valve 14 Valve 20 Cement firing equipment 21 Cement kiln 23 Burner

Claims (7)

Mixing waste sludge and liquid fuel,
Crushing the mixture obtained by the mixing,
A method of converting waste sludge into fuel, wherein the crushed material obtained by the crushing is introduced into a combustion furnace and burned in the combustion furnace.   2. The waste sludge according to claim 1, wherein the waste sludge is at least one selected from the group consisting of waste paint sludge, waste solvent distillation residue, waste grease, oil sludge, waste ink, and waste clay. Fueling method.   2. The method of converting waste sludge into fuel according to claim 1, wherein the liquid fuel is at least one selected from the group consisting of waste solvent, waste oil, waste paint, emulsion fuel, and organic substance-containing waste liquid.   The waste sludge according to claim 1, 2 or 3, wherein the crushed material is introduced from one or more locations selected from the group consisting of a kiln front part, a kiln bottom part and a calcining furnace of a cement kiln. Fueling method. A mixing device for mixing waste sludge and liquid fuel;
A first supply device for supplying waste sludge to the mixing device;
A second supply device for supplying liquid fuel to the mixing device;
A crushing device for crushing the mixture mixed by the mixing device;
A waste sludge fueling system comprising: a third supply device for introducing the crushed material crushed by the crushing device into a combustion furnace.   The waste sludge fueling system according to claim 5, wherein the first supply device includes a piston pump, a twin screw pump, a Mono pump, or a rotary pump. The first supply device includes a supply pipe inserted to the inside of the mixing device,
5. The waste sludge fueling system according to claim 4, wherein the supply pipe includes a dispersion plate that disperses the waste sludge when the waste sludge is supplied to an end of the mixing apparatus. .

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