JP2740790B2 - Pure steam generator for food - Google Patents

Description

The present invention relates to a pure steam generator that effectively separates and removes foreign matters such as iron and silica contained in live steam generated in a boiler, and in particular, Related to those suitable for use in the food industry.

[Conventional technology]

In the food industry described below, a manufacturing method in which boiler steam is directly blown into food ingredients is used.

Tofu industry: Heated steaming process of soy milk Boiled bean industry: Water boiling process of soybeans Natto industry: Steaming process of soybeans Chestnut dew boiled industry: Water steaming process of chestnuts Pickle industry: Sterilization process of canned cans Industry of soymilk beverages etc .: Direct heating type Liquid continuous sterilization process By the way, the live steam of the boiler contains a large amount of iron, chloride ions, silica, foreign substances and the like due to boiler additives, and when this live steam is directly blown into food ingredients,
The surface of beans and chestnuts turns black due to the formation of tannin iron, which has the detrimental effect of losing its commercial value. In addition, the incorporation of a large amount of foreign substances is not preferable in food hygiene. Therefore, conventionally, in the food industry, the following technical measures have been taken to prevent and remove foreign matter in live steam.

Use of food boiler additives.

Stainless steel steam piping.

Take out steam from the top of the steam main pipe,
Install a steam trap for drain discharge in the main piping.

Attach a steam filter (about 1 μm mesh).

The entrained particles including foreign matter are removed by a cyclone.

[Problems to be Solved by the Invention] Use of Food Boiler Additives Food boiler additives include a tin can: an aqueous solution of sodium hydroxide, sodium carbonate and tannin, and an oxygen scavenger: sodium sulfite. In the steam obtained by using the above additive, a large amount of foreign matters and the like due to iron, chloride ions, silica and boiler additives remain, and the above-mentioned problems have not been sufficiently solved.

The use of stainless steel for the steam pipe can be expected to have an effect of reducing the mixing ratio of iron, but cannot prevent the mixing of other foreign substances.

The steam pipe section has the effect of suppressing the mixing of drain, but it cannot be a drastic means for removing foreign matter.

Use of a steam filter Insoluble solids can be removed, but soluble solids cannot.

Cyclone method Since the flow rate of the entrained particles in the steam pipe is high and the particles are too fine, the collection efficiency of the cyclone is extremely low.

As described above, the conventional solution is completely insufficient in terms of effect, and cannot be a drastic solution for solving the problem. Further, there is a great possibility that the numerical value of the foreign matter component will be significantly increased due to a change in the operation state of the boiler. For this reason, some of these food industries have introduced indirect pure steam generators for pyrogen-free use in the pharmaceutical industry. However, since this pure steam generator requires a pretreatment facility incorporating ion exchange resin, the initial cost is high, and there are economical problems for use in the food industry, and water supply is required. In addition, there is a problem that a large amount of wastewater is discharged.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an inexpensive pure steam generator that can reliably generate a pure steam that can be used in the food industry, has a simple structure, and is compact.

[Means for Solving the Problems] The pure steam generator for food of the present invention is a free-standing container having a liquid stored at the bottom, and is directly connected to the upper portion of the container, and the separated product outlet is provided inside the container. And a cyclone housed in the sea. Then, after the boiler's live steam is supplied into the liquid at the bottom from the inlet provided at the bottom of the container and once condensed, it is re-evaporated at the gas-liquid interface of the liquid at the bottom,
The re-evaporated steam is introduced into a cyclone to separate and remove the entrained droplets, resulting in almost 100% dryness.
And a heat exchange system that does not require replenishment of the bottom liquid by returning the cyclone separated liquid from the separated substance outlet to the bottom of the container. .

Further, a punching metal formed of a plate having a plurality of openings may be mounted in the bottom liquid of the container.

[Action]

The live steam blown into the liquid at the bottom of the container is deprived of heat and condenses when coming into contact with the liquid. The vapor once condensed regains its calorific value from the live steam newly blown into the liquid and re-evaporates from the gas-liquid interface. As described above, heat exchange is directly performed between the live steam and the condensed steam, and the live steam is once held in the liquid and then re-evaporates from the gas-liquid interface. For this reason, the flow velocity of the steam is lower than at the beginning, and accordingly, the diameter of the entrained particles containing foreign matter increases. The re-evaporated vapor is led into a cyclone connected to the gas-liquid separation section, where the entrained particles are separated and removed by the cyclone to become pure steam. Since the entrained particles have a low speed and a large diameter due to re-evaporation, they are efficiently collected by the cyclone and reliably separated from the vapor. As a result, the steam flowing out of the cyclone becomes a pure steam with high purity and almost 100% dryness. Further, the entrained droplets separated by the cyclone are liquefied and returned to the bottom of the container. Therefore, it is not necessary to supply the liquid at the bottom.

On the other hand, it is assumed that the live steam blown into the liquid does not condense, passes through the liquid in a high-speed state, and flows into the cyclone. In this case, since the entrained particles are still in a miniaturized state, a reduction in cyclone collection efficiency becomes a problem. The punching metal is mounted in order to cope with such a case, and the passing of the live steam blown into the liquid is restricted by the punching metal, and the surface becomes large as fine bubbles. For this reason, the gas-liquid contact area increases, and the live steam is efficiently condensed.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a pure steam generator for food according to the present invention. The pure steam generator includes a condensing section (3a) for blowing live steam (1) generated by a boiler (not shown) into a liquid (2) stored at the bottom to temporarily condense the steam, and a condensed steam. (3) having a gas-liquid separation part (3b) for re-evaporating the water at the gas-liquid interface (2a), and a cyclone (5) directly connected to the upper part of the container (3) as main components. . In the present embodiment, the material of the liquid contacting parts such as the container (3) and the pipe part is made of stainless steel (SUS316), and boiler water is used as the liquid (2).

The container (3) is a self-standing container having a cylindrical shape. The condenser (3a) has an inlet (3c) for introducing live steam (1), and a drain (drip) collected on the bottom surface. A drain outlet (3d) is formed. In the liquid (2), two punching metals (6) are vertically separated from each other. The punching metal (6) is provided with a plurality of openings (6a) in a circular plate made of stainless steel, and is attached to the inner diameter portion of the container (3) by an appropriate means. The positions of the openings (6a) are shifted from each other in a state where the punching metals (6) are arranged vertically. An outlet (3e) for discharging the re-evaporated vapor is formed above the gas-liquid separation section (3b).
e) communicates with the inlet (5a) of the cyclone (5) via the external pipe (7).

The cyclone (5) is directly connected to the lid (3f) of the container (3), and the separated material outlet (5b) is located in the gas-liquid separation part (3b). (5c) is an outlet for letting out the pure steam (8) after the foreign matter is separated and removed.

In the figure, reference numeral (3g) denotes a supply port for supplying the liquid (2), which is closed after supplying the liquid (2) first and storing it at the bottom. Further, (9) is a pressure equalizing pipe communicating with the blow valve (10). The drip drain collected on the bottom of the container (3) flows into the blow valve (10) from the drain outlet (3d), and is discharged from the drain valve (12) or (13) to the drain pipe. The equalizing pipe (9) is connected to the container (3) and the blow valve (1
0), the pressure inside the blow valve (1)
It prevents backflow from 0) into the container (3). When the liquid (2) in the container (3) increases and the liquid level rises, the overflow is discharged from the liquid drain valves (12) and (13).

The live steam (1) blown into the liquid (2) from the inlet (3c) loses heat when it comes into contact with the liquid (2), and once condenses. At this time, the punching metal (6) functions to regulate the rise of the live steam (1) in the liquid and to condense efficiently. The condensed steam obtains the calorific value of the freshly blown live steam (1) and re-evaporates from the gas-liquid interface (2a). The vapor (11) rises in the gas-liquid separator (3b), is once taken out of the container (3) from the outlet (3e), and is introduced into the cyclone (5) by the external pipe (7). .
As the steam (11) swirls inside the cyclone (5),
The entrained particles are separated by centrifugal force, and the dryness is almost
Outlet (5c) as 100% pure team (8)
Spill out of. The entrained liquid separated by the cyclone (5) is liquefied, reaches the inner wall of the container (3) from the separation outlet (5b) at the lower end of the cyclone (5) through the drain pipe, and flows the inner wall. To the liquid (2). for that reason,
There is no decrease in liquid (2) and no replenishment is required.

〔The invention's effect〕

The pure steam generator for food according to the present invention condenses the live steam of the boiler once in the liquid at the bottom of the container, and introduces the vapor re-evaporated at the gas-liquid interface into the cyclone to thereby generate the entrained particles containing foreign matter. It has a configuration to separate and remove. Therefore, according to the present invention, the diameter of the entrained particles increases with a decrease in the steam flow rate, and the cyclone collection efficiency is significantly improved. Therefore, foreign matter components in the steam are extremely effectively removed. The amount of entrained particles contained in the extracted steam is 1/10000 to 1/100000 (weight ratio) compared to live steam.
It has been experimentally confirmed that the concentration of foreign matter is 1/100 or less of that of live steam, and it is possible to obtain a pure steam with almost 100% dryness that can sufficiently satisfy the steam purity required in the food industry. be able to.

In addition, the pure steam generator is simple and compact in structure, does not require liquid replenishment, and does not require special pretreatment equipment, so that it is inexpensive and economically advantageous.

[Brief description of the drawings]

FIG. 1 is a structural model diagram of a food pure steam generator according to the present invention. 1 ... Live steam, 2 ... Liquid 2a: Gas-liquid interface 3 ... Container, 5 ... Cyclone 3a: Condensing part, 6 ... Punching metal 3b: Gas-liquid separating part, 6a: Opening 11 ... Re-evaporated steam, 8 ... Pure steam

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-193502 (JP, A) JP-A-2-64301 (JP, A) JP-A-63-247503 (JP, A) 142507 (JP, U)

Claims (2)

(57) [Claims] 1. A self-contained container having a liquid stored at a bottom portion, and a cyclone directly connected to an upper portion of the container and having an outlet for separating the separated product contained in the container. After the raw steam from the boiler is supplied into the liquid at the bottom from an inlet provided at the bottom of the vessel and once condensed, the vapor is re-evaporated at the gas-liquid interface of the liquid at the bottom, and the re-evaporated steam is discharged. By introducing the cyclone into the cyclone and separating and removing the droplets, a pure steam having a dryness of almost 100% is generated, and the separated liquid of the cyclone is returned from the separated material outlet to the bottom of the container. A pure steam generator for foods, wherein a heat exchange system is formed which does not require replenishment of the bottom liquid. 2. A pure steam generator, wherein a punching metal formed of a plate having a plurality of openings formed therein is mounted in a liquid at the bottom of the container.