JP2013075943A - Apparatus and method for recovering palmitic acid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for recovering palmitic acid, with which palmitic acid as valuables can be efficiently recovered from sludge.SOLUTION: A carrier gas including no oxygen is supplied into a sample hopper 7 and into a reaction tube 1 to produce an oxygen-free atmosphere. After the reaction tube 1 is heated to 300-700°C by an electric heater 3, the sludge 13 is placed on a sample holder 5. A gas is generated by heating the sludge 13 under an oxygen-free carrier gas atmosphere. The generated gas is supplied to a recovery tube 11b in a gas cooling part 11 through a tube 12, and is cooled in the recovery tube 11b, and tar of the condensed component is collected in the recovery tube 11b. Palmitic acid is extracted from the tar, and is recovered.

Description

  The present invention relates to a palmitic acid recovery apparatus and a palmitic acid recovery method for recovering palmitic acid from sludge.

  Conventionally, various energy conversion processes using biomass as a raw material have been developed. In particular, many researches and developments have been made on energy conversion technology using woody biomass as a raw material. However, wood biomass energy conversion technology has not been commercialized due to problems such as the cost of wood biomass as a raw material.

  Therefore, in recent years, energy conversion technology using sludge as a raw material for which collection technology has been established attracts attention, and research and development is being promoted for energy conversion technology such as carbonization and gasification.

  As an energy conversion technique using such sludge as a raw material, the technique described in Patent Document 1 is known. In Patent Document 1, organic waste is put into a fluidized bed gasifier and pyrolyzed into a pyrolysis residue containing pyrolysis gas, tar and carbon in a low oxygen atmosphere with an air ratio of 1 or less. The pyrolysis residue is recovered by a cyclone apparatus provided at the latter stage of the gasification furnace, and tar and pyrolysis gas are supplied to the reformer provided at the latter stage of the cyclone apparatus to generate the reformed gas. A technique for using the reformed gas as an energy source of a generator is disclosed. According to this technique, it is possible to recover the pyrolysis residue containing carbides while generating the necessary amount of in-house power. In addition, a method for reducing the molecular weight of a tar generated by gasification in a gasification furnace with a catalyst to obtain a fuel is also known.

  Furthermore, as a similar energy conversion technique, the technique described in Patent Document 2 is also known. In Patent Document 2, municipal waste and biomass are pyrolyzed in a gasification furnace, the resulting pyrolysis gas is reformed in a reforming furnace to generate reformed gas, and this reformed gas is removed with harmful components. A technology is disclosed in which, after being purified by an apparatus, the generated refined gas is used as a fuel to generate power with a power generation apparatus.

  With the progress of such energy conversion technology, technology for recovering valuable materials from sludge is also being developed. In Patent Document 3, sewage sludge incineration ash and an alkaline reaction liquid are mixed in a reaction tank to extract phosphorus contained in the sewage sludge incineration ash into the liquid, and then the liquid is separated into a phosphorus extract and treated ash. A technique for separating and adding calcium components to the phosphorus extract to extract calcium phosphate crystals is described.

JP 2007-229563 A JP 2009-228958 A JP 2008-230940 A

  By the way, considering the recovery of valuable materials from sludge, according to the study of the present inventor, it is considered that the sludge contains various valuable valuable materials other than flammable gas and phosphorus. However, sludge contains various components such as microorganisms composed of peptidoglycan and fats and oils discharged from households, and it is difficult to specify the thermal decomposition behavior of sludge and the generation behavior of tar during thermal decomposition. Yes, little is revealed.

  For this reason, development of a technology for recovering valuable materials that have not been collected in the past among the valuable materials contained in the sludge has been demanded.

  The present invention has been made in view of the above, and an object thereof is to provide a palmitic acid recovery apparatus and a palmitic acid recovery method capable of efficiently recovering palmitic acid as a valuable material from sludge. .

  In order to solve the above-described problems and achieve the above object, the present inventor has conducted various experiments and intensively studied. First, the present inventor has found through experiments that tar obtained by cooling gas released by heating sludge contains valuable palmitic acid as a kind of fatty acid. This palmitic acid is a very useful valuable material used for cosmetics, surfactants, biodiesel, etc., but there has been no knowledge that it can be recovered from sludge.

  Accordingly, the present inventor has studied a method for recovering palmitic acid from sludge, and has conducted various experiments and studies on what conditions are necessary to obtain palmitic acid from sludge. And when this inventor produces | generates tar in the atmosphere of water vapor | steam and air like the gasification technique described in patent document 1, 2, it discovers that the obtained tar does not contain palmitic acid. It came to. As a result of repeated experiments and examinations based on this knowledge by the present inventors, the atmosphere when generating gas by heating the sludge is released by heating the sludge. When the gas was cooled to obtain tar, this tar was found to contain a large amount of palmitic acid. The present invention has been devised based on the above studies.

  Therefore, the palmitic acid recovery apparatus according to the present invention includes an oxygen-free heating means configured to heat sludge in an oxygen-free atmosphere, a cooling means configured to cool gas generated from the sludge, and a cooling means. And a storage means for storing tar containing palmitic acid obtained from the cooled gas.

  In the palmitic acid recovery apparatus according to the present invention, in the above invention, the heating temperature of the sludge by the oxygen-free heating means is typically 300 ° C. or higher and 700 ° C. or lower, preferably 350 ° C. or higher and 550 ° C. or lower. It is characterized by that.

  The palmitic acid recovery method according to the present invention includes an oxygen-free heating step for heating sludge in an oxygen-free atmosphere, and a cooling and recovery step for generating and recovering tar by cooling gas generated from the sludge. And

  In the palmitic acid recovery method according to the present invention, in the above invention, the heating temperature in the oxygen-free heating step is typically 300 ° C. or higher and 700 ° C. or lower, preferably 350 ° C. or higher and 550 ° C. or lower. Features.

  According to the palmitic acid recovery device and the palmitic acid recovery method of the present invention, it is possible to efficiently recover palmitic acid, which is a valuable fatty acid, from sludge.

FIG. 1 is a schematic diagram showing a configuration of a palmitic acid recovery apparatus according to an embodiment of the present invention. FIG. 2 is a graph showing the heating temperature dependence of the main components contained in the tar component obtained by the recovery method according to one embodiment of the present invention.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, this invention is not limited by embodiment described below.

  First, the palmitic acid collection | recovery apparatus by one Embodiment of this invention is demonstrated. FIG. 1 shows a palmitic acid recovery apparatus according to this embodiment.

  As shown in FIG. 1, a palmitic acid recovery apparatus according to this embodiment includes a reaction tube 1, a stainless tube 2, an electric heater 3 as a heating means, a heat insulating member 4, a sample holder 5, a thermocouple 6, a sample hopper 7, A ball valve 8, a gas inflow pipe 9, a bypass pipe 10, a gas cooling section 11 as a cooling means, and a tube 12 are configured.

  The reaction tube 1 is a cylindrical quartz tube made of, for example, quartz, and has an inner diameter of, for example, 14 mm and a length of, for example, 670 mm. The sample holder 5 inside the reaction tube 1 is made of, for example, glass cotton, and is provided at a height of, for example, 270 mm from the lower end of the reaction tube 1. Sludge 13 is dropped on the sample holder 5 so that it can be placed thereon.

  The stainless steel tube 2 has a cylindrical shape and is provided so as to surround the side surface of the reaction tube 1. Furthermore, an electric heater 3 is provided so as to surround the side surface of the stainless steel tube 2. The stainless steel tube 2 and the electric heater 3 constitute a stainless tubular furnace, and the reaction tube 1 can be uniformly heated to a predetermined temperature, for example, 850 ° C. Further, a heat insulating member 4 is provided so as to surround the electric heater 3. The thermocouple 6 is provided between the reaction tube 1 and the stainless steel tube 2 and between the stainless steel tube 2 and the electric heater 3 so that the temperature of the reaction tube 1 can be measured.

The sample hopper 7 is connected to the upper part of the reaction tube 1 via a ball valve 8. A gas inflow pipe 9 is connected to the upper portion of the sample hopper 7, and for example, oxygen-free carrier gas from a gas supply device (not shown) for supplying nitrogen (N ₂ ) gas or the like is supplied to the inside of the sample hopper 7. It is the piping which supplies to. Thereby, the inside of the sample hopper 7 can be made an oxygen-free atmosphere containing no oxygen. In addition, it is comprised so that the sludge 13 inside the sample hopper 7 may be maintained at normal temperature.

  The ball valve 8 is provided between the reaction tube 1 and the sample hopper 7 so as to be openable and closable so as to communicate or block them. When the ball valve 8 is open, the reaction tube 1 and the sample hopper 7 communicate with each other, and the carrier gas is supplied directly to the reaction tube 1 through the gas inflow pipe 9 and the sample hopper 7. On the other hand, when the ball valve 8 is in the closed state, the carrier gas is supplied to the reaction tube 1 through the gas inflow piping 9 and the sample hopper 7, with the ball valve 8 being bypassed by the bypass piping 10.

  A gas cooling unit 11 as a cooling means is provided below the reaction tube 1. The gas cooling unit 11 evacuates a cooling container 11a in which a coolant such as ice and water is stored, a recovery pipe 11b as a storage means for recovering and storing tar, and a gas inside the cooling container 11a. And an exhaust pipe 11c. A tube 12 communicating with the inside of the reaction tube 1 is inserted into the collection tube 11b. In the gas cooling unit 11 configured as described above, the gas inside the reaction tube 1 is first supplied to the recovery tube 11b through the tube 12, cooled by ice and water in the cooling vessel 11a, and then cooled from the recovery tube 11b to the cooling vessel. 11a and exhaust pipe 11c are sequentially passed through and exhausted to the outside.

  Next, a palmitic acid recovery method according to an embodiment of the present invention using the palmitic acid recovery apparatus configured as described above will be described.

  First, in this embodiment, as the sludge 13, for example, 4.6 g of dried sludge in a pellet form is used. Here, the sludge 13 made of this dried sludge has a carbon content of about 50%, an ash content of about 15%, and a nitrogen content of about 6%. In addition, about the ash and nitrogen content of this sludge 13, it is large compared with the ash content in woody biomass being about 0.7% and the nitrogen content being 0.1% or less. .

  Next, as shown in FIG. 1, first, the ball valve 8 is closed, and the sludge 13 is sealed in the sample hopper 7. Subsequently, a carrier gas not containing oxygen such as nitrogen gas is supplied into the sample hopper 7 at a predetermined flow rate from an external gas supply device (not shown) through the gas inflow pipe 9. Here, the predetermined flow rate of the carrier gas is, for example, 35 ml / min. On the other hand, the carrier gas is also supplied to the inside of the reaction tube 1 through the bypass pipe 10, and the inside of the reaction tube 1 is in an oxygen-free state.

  Next, while flowing the carrier gas into the reaction tube 1, the reaction tube 1 is heated by the electric heater 3 until it reaches a predetermined temperature in the range of 300 to 700 ° C., preferably 350 to 550 ° C. The temperature at this time is measured by the thermocouple 6. After the inside of the reaction tube 1 is heated to the predetermined temperature, the ball valve 8 is operated to open it. Thus, the sludge 13 is dropped into the reaction tube 1 by gravity and placed on the sample holder 5.

  The sludge 13 placed on the sample holder 5 of the reaction tube 1 is rapidly heated to a predetermined temperature and heated in an oxygen-free carrier gas atmosphere. By this heating, volatile components and pyrolysis components are generated as gas from the sludge 13. In addition, the heating with respect to the sludge 13 is performed for a predetermined time, specifically 40 minutes. Gas generated by heating the sludge for a predetermined time is supplied to the gas cooling unit 11 through the tube 12 according to the flow of the carrier gas.

  When the generated gas is supplied to the recovery pipe 11b of the gas cooling unit 11, the gas inside the recovery pipe 11b is cooled by a coolant such as ice and water in the cooling container 11a. The condensed component in the cooled gas becomes tar and is collected inside the recovery pipe 11b. Note that the tar generated by the gas leaking to the outside of the recovery pipe 11b adhering to the inner wall of the cooling container 11a or the inside of the tube 12 is recovered by washing with acetone. On the other hand, the non-condensed component (gas component) is exhausted to the outside from the recovery pipe 11b through the space of the cooling container 11a and the exhaust pipe 11c.

  The tar (condensed component) collected in the recovery tube 11b contains palmitic acid, and palmitic acid is extracted from the tar and recovered by a conventionally known method.

  Next, based on the palmitic acid recovery method using the palmitic acid recovery apparatus configured as described above, various components contained in the tar with various predetermined temperatures when the sludge 13 in the reaction tube 1 is heated are used. The temperature dependence of the content of was analyzed. In this embodiment, 300 ° C., 400 ° C., 600 ° C., and 700 ° C. are employed as the predetermined temperature when the sludge 13 is heated. The measurement results are shown in FIG.

  According to the graph of the temperature dependence of the contents of various components contained in the tar shown in FIG. 2, the tar components include palmitic acid, 4-methyl-3-penten-2-one, diacetone alcohol, acetic acid, and 2 2,6,6-tetramethyl-4-piperidinone. And in these various containing components, when the predetermined temperature at the time of heating is the range of 300-700 degreeC, it turns out that many palmitic acids are contained compared with another containing component. That is, when the sludge 13 is heated to 300 to 700 ° C. as the predetermined temperature when the sludge 13 is heated inside the reaction tube 1, palmitic acid can be recovered over the other components. Furthermore, since the amount of palmitic acid recovered is highest when the predetermined temperature during heating is around 400 ° C., the predetermined temperature during heating is in a temperature range including 400 ° C., specifically, 350 to 550 ° C. By doing so, palmitic acid can be recovered more efficiently.

  According to one embodiment of the present invention described above, the gas generated from the sludge is cooled by heating the sludge at a temperature of 300 to 700 ° C., preferably 350 to 550 ° C. in an oxygen-free atmosphere. By collecting the tar component, the tar containing palmitic acid can be easily purified from the sludge, and a valuable material called palmitic acid can be easily recovered.

  In the above-described embodiment, when supplying the carrier gas not containing oxygen from the sample hopper 7 to the reaction tube 1 with the ball valve 8 closed, the carrier gas is supplied through the bypass pipe 10. The carrier gas not containing oxygen may be directly supplied into the reaction tube 1 from a gas supply device (not shown).

  In the above-described embodiment, the sample hopper 7 is provided above the reaction tube 1 and the gas cooling unit 11 is provided below. However, the positional relationship between the reaction tube 1, the sample hopper 7, and the gas cooling unit 11 is as follows. It is not necessarily limited to this. That is, the sample hopper 7 and the gas cooling unit 11 may be provided on the left and right sides of the reaction tube 1, the sample hopper 7 is provided below the reaction tube 1, and the gas cooling unit 11 is provided above the reaction tube 1. May be. Further, the sludge 13 can be directly placed on the sample holder 5 without providing the sample hopper 7.

  Furthermore, in the above-described embodiment, the gas inside the cooling container 11a in the gas cooling unit 11 is exhausted to the outside through the exhaust pipe 11c. The gas exhausted from the exhaust pipe 11c is, for example, It can also be configured to collect in a collection tank such as a gas sampling bag. Moreover, although the so-called ice water of ice and water is used as the coolant inside the cooling container 11a, other coolants can also be used, for example, dry ice can be used.

DESCRIPTION OF SYMBOLS 1 Reaction tube 2 Stainless steel tube 3 Electric heater 4 Heat insulation member 5 Sample holder 6 Thermocouple 7 Sample hopper 8 Ball valve 9 Gas inflow piping 10 Bypass piping 11 Gas cooling part 11a Cooling vessel 11b Recovery pipe 11c Exhaust pipe 12 Tube 13 Sludge

Claims (6)

Oxygen-free heating means configured to heat sludge in an oxygen-free atmosphere;
A cooling means configured to cool the gas generated from the sludge;
And a storage means for storing tar containing palmitic acid obtained from the gas cooled by the cooling means.   The palmitic acid recovery apparatus according to claim 1, wherein a heating temperature of the sludge by the oxygen-free heating means is 300 ° C or higher and 700 ° C or lower.   The palmitic acid recovery apparatus according to claim 1, wherein a heating temperature of the sludge by the oxygen-free heating means is 350 ° C or higher and 550 ° C or lower. An oxygen-free heating step for heating sludge in an oxygen-free atmosphere;
A cooling recovery step of cooling the gas generated from the sludge to generate and recover tar, and recovering the palmitic acid.   The method for recovering palmitic acid according to claim 4, wherein a heating temperature in the oxygen-free heating step is 300 ° C or higher and 700 ° C or lower.   The method for recovering palmitic acid according to claim 4, wherein the heating temperature in the oxygen-free heating step is 350 ° C or higher and 550 ° C or lower.

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