WO2005036959A2

WO2005036959A2 - Electric fumigation apparatus

Info

Publication number: WO2005036959A2
Application number: PCT/KR2004/002675
Authority: WO
Inventors: Kyung-Woo Lee
Original assignee: Handoo Ipem Co., Ltd.
Priority date: 2003-10-20
Filing date: 2004-10-19
Publication date: 2005-04-28
Also published as: WO2005036959A3

Abstract

The present invention is a fumigation apparatus comprising: a container (10) which has an empty inner space with a predetermined volume for storing sulfur therein, of which an upper portion is open; a heating plate (20) for heating the container to a predetermined temperature, which contacts with a bottom of the container (10); a heating means (30) for heating the heating plate (20); a heat-transferring element (40) which is upwardly projected by a predetermined height from the bottom of the container (10); a porous film (50) with a predetermined thickness formed on an inner surface and a bottom of the container (10) and on a surface of the heat-transferring element (40); and a temperature-controlling means for controlling a heating temperature wherein the bottom of the container (10) and an upper surface of the heating plate (20), which are opposite to each other, are divided into a plurality of partitions, and opposite surfaces of the respective partition are inclined by a predetermined degree, so that the heating temperature can be controlled by a contact area between the container (10) and the heating plate (20) when the container is rotated by a predetermined degree.

Description

ELECTRIC FUMIGATION APPARATUS

Technical Field The present invention relates to an electric fumigation apparatus. In particular, the electric fumigation apparatus has a porous film formed at an inner surface of a container which is in contact with liquid sulfur, insecticide, fungicide or insect repellent, thereby increasing sharply the liquid surface area by osmotic action, and expanding the evaporative area of the liquid surface being contacted with atmosphere so that the evaporativity of the sulfur or liquid to be fumigated may be maximized.

Background Art In general, the control device for spraying the pesticides on the crops may be classified into a spray type, a fog type, a smoke type, and a fumigation type; wherein the spray type is to spray the pesticides, which is diluted with a large quantity of water, by a sprayer on the crops; the fog type is to diffuse the pesticides using heat of exliaust gas from a jet engine; the smoke type is to diffuse the pesticides in the form of smoke; and the fumigation type is to apply active ingredients as a vapor or gaseous state in an enclosed space. In the commonly used spray type, the pesticides is diluted with a large quantity of water and sprayed by a sprayer. The spray type is generally used for spraying pesticides onto crops cultivated on an exposed land, but problems occurs in a greenhouse since a worker has to spray directly onto the crops, and accordingly the worker may be poisoned by the toxic chemicals. Thus, the worker must pay careful attention and also must be equipped with thoroughgoing protective implements when spraying the chemicals. In the fumigation type, which is used in an airtight space differently from the spray type, the chemicals such as sulfur or chemicals, mainly solid, powder or liquid state of fumigant, mixed with a predetermined additive are put in a container for heating, and the container is heated electrically to evaporate and introduce an active ingredient onto the crops, whereby pests or diseases are controlled more effectively since the chemicals act as ultra-small particles vapor state, and the fumigation type has a simple structure. In addition, the fumigation type enables the operation to be performed at night automatically when one does not work and so it has been mainly used in an airtight space. Meanwhile, sulfur which is mainly used in the fumigation device is effective in controlling pests and diseases in organically growing plants, and is an environmental friendly material having safety authorized internationally. In particular, sulfur is inexpensive compared with the other chemicals, sulfur does not have tolerance or a chemical-resistance, thus it can be used continuously. Furthermore, in a closed space such as in a greenhouse, the sulfur fumigating method is performed by heating sulfur in a solid or in powder state up to a predetermined temperature to vaporize the sulfur and fill the space with the vapor of sulfur to control pests and diseases. Therefore, the sulfur fumigating method does not make toxic residues in comparison with general chemicals, and thus it is proper for producing organically growing crops. Also, the automatic operation is possible at night and so any additional worker's effort is not necessary. However, sulfur is a flammable and very dangerous material having a melting point 114^°C, a flashing point 207.2 ^°C, and an ignition point 255 ^°C, and the burned sulfur becomes fatally poisonous sulfur dioxide gas to do considerable damage to facilities as well as human body and plants In addition, sulfur is changed into a yellow liquid state at 114^°C, a fungicide effect decreases as temperature increases, whereas a viscosity of sulfur liquid increases as temperature increases. The sulfur becomes a dark orange liquid state with a high viscosity at about 160^°C, and then is getting black to be spontaneously burnt at a combustion temperature of 414°C . The conventional fumigation type device using sulfur has a simple structure as shown in Fig. 1, which comprises a container 10 for filling a predetermined amount of sulfur, a heating plate 20 placed under a bottom of the container 10, and heating means 30 for heating the heating plate 20. In the conventional fumigation type device, when powder sulfur is put in the container 10, and the heating plate 20 is heated by the heating means 30 and melted, there occurs a temperature difference of 20~80 ^°C between liquid sulfur in the lower position and liquid sulfur in the upper position, depending on the amount of sulfur and the surrounding temperature due to the low thermal conductivity of liquid sulfur. For example, when the heating plate 20 is heated to a temperature of about 240 °C by the heating means 30, sulfur in the lower position is kept on temperature of about 200 ^°C , and sulfur in the upper position is at about 150^°C . Accordingly, there are problems that the temperature of sulfur in the lower position is considerably different from in the upper position. The evaporation amount depends on only the temperature of upper position and so the fungicidal effect of liquid sulfur in the low position exposed at relatively high temperature is gradually decreased.

In addition, some organic acids of agricultural chemicals or fertilizers sprayed frequently in the greenhouse may be penetrated into sulfur in the container to decrease the combustion point of sulfur and to make problem of burning sulfur. Furthermore, to prevent sulfur from being burnt, a sulfur fumigation device is required in which sulfur is evaporated by making the heating temperature as lower as possible. In addition, in the conventional device, the evaporation rate of sulfur may be remarkably affected depending on the amount of sulfur in the container 10 and the atmosphere temperature, so that it is difficult to accurately forecast the fumigation amount, and thus its use is limited only for some crops which is less or not sensitive to the sulfur. Furthermore, the conventional device has problems that the sulfur in the container 10 should be continuously heated under a high temperature and so its fungicidal effect may be getting decreased, whereby the whole of sulfur must be regularly replaced. Thus, the environment may be polluted due to the waste sulfur, and also there can be a danger of fire resulting in the fatal gas over a wide area when the waste sulfur is burnt due to carelessness. The present applicant has recently filed a patent application serial No. 2001-

83968 entitled "Fumigation type control device" wherein a heat-transferring element 40 is upwardly projected to a predetermined height from a bottom surface of the heating plate 20, and thereby an area for heating sulfur may be increased. When sulfur is evaporated using the above heat-transferring element 40, there is an advantage in that the heating area of sulfur is expanded to generate some more amount of sulfur vapor and thus it is possible to evaporate a certain amount of sulfur at a lower temperature. However, there are problems that since there is still a considerable difference in the temperature of sulfur on a bottom surface and in the upper position inside the container 10, high temperature for heating is required, thereby there exists a danger of fire, and the evaporation amount of sulfur is remarkably reduced, particularly at a temperature of less than the temperature of 180 °C .

Disclosure of Invention To solve the above-indicated problems, it is, therefore, an object of the present invention is to provide a fumigation apparatus including a porous film formed on a surface of the heat-transferring element and an internal surface of a container which is contacted with sulfur to expand a liquid surface area of sulfur being exposed to atmosphere by a porous film, and also to obtain a required amount of sulfur vapor at a low temperature and to improve the safety of the apparatus.

To achieve the above object, the fumigation apparatus according to the present invention comprises: a container which has an empty inner space with a predetermined volume for storing sulfur therein, of which an upper portion is open; a heating plate for heating the container to a predetermined temperature, which contacts with a bottom of the container; a heating means for heating the heating plate; a heat-transferring element which is upwardly projected by a predetermined height from the bottom of the container; and a porous film with a predetermined thickness formed on an inner surface and the bottom of the container and on a surface of the heat-transferring element. Furthermore, another fumigation apparatus according to the present invention comprises: a container which has an empty inner space with a predetermined volume for storing sulfur therein, of which an upper portion is open; a heating plate for heating the container to a predetermined temperature, which contacts with a bottom of the container; a heating means for heating the heating plate; a heat-transferring element which is upwardly projected by a predetermined height from the bottom of the container; a porous film with a predetermined thickness formed on an inner surface and a bottom of the container and on a surface of the heat-transferring element; and a temperature-controlling means for controlling a heating temperature wherein the bottom of the container and an upper surface of the heating plate, which are opposite to each other, are divided into a plurality of partitions, and opposite surfaces of the respective partition are inclined by a predetermined degree, so that the heating temperature can be controlled by a contact area between the container and the heating plate when the container is rotated by a predetermined degree.

Brief Description of Drawings The above objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: Fig. 1 is a side cross-sectional view o f a conventional fumigation apparatus; Fig. 2 is a side cross-sectional view of a fumigation apparatus of a former application filed by the present applicant; Fig. 3 is a side cross-sectional view of the fumigation apparatus according to one embodiment of the present invention; Fig. 4 is a side cross-sectional view of the fumigation apparatus according to another embodiment of the present invention, wherein a part for accommodating different chemicals, such as insecticide or repellents, is changed.; Fig. 5 is a plane cross-sectional view along A- A line of Fig. 4; Fig. 6 is a cross-sectional view of the fumigation apparatus according to another embodiment of the present invention, wherein a heat-transferring element is changed; Fig. 7 is a side cross-sectional view of the fumigation apparatus according to another embodiment of the present invention; Fig. 8 is a side cross-sectional view of Fig. 7. Fig. 9 is a side cross-sectional view of showing a structure in which the accommodating part for liquid chemicals is engaged with the cartridge for liquid chemicals. Fig. 10 is a side cross-sectional view of showing the fumigation apparatus according to another embodiment of the present invention. Fig. 11 is side cross-sectional view of showing a structure in which the cartridge for liquid chemicals is engaged between the container and the protective cover; and Figs. 12 and 13 are side cross-sectional views of showing operation states in which a contact area with the heating plate is changed by a rotation of the container according to the present invention, thereby adjusting parts to be heated. Best Mode for carrying out the Invention

A preferred embodiment of the present invention will now be described with reference to the accompanying drawings. In the following description, same drawing reference numerals are used for the same elements even in different drawings. As shown in Fig. 3, the fumigation apparatus according to the present invention comprises a container 10 for storing sulfur therein; a heating plate 20 for heating a bottom of the container 10 to a predetermined temperature, which contacts with the bottom of the container 10; a heating means 30 for directly heating the heating plate 20; and a heat-transferring element 40 which is upwardly projected by a predetermined height from the bottom of the container 10, which are similar to those of the conventional apparatus.

The above container 10 is integrally formed by casting, e.g., die casting using the material with a very high thermal conductivity such as aluminum alloy. This container has an empty inner space with a predetermined volume for storing sulfur therein, of which an upper portion is open.

The heating plate 20 is a plate formed of the material with a high thermal conductivity, being contacted tightly with the bottom of the container, and the heating means 30 is an element for generating heat for heating the heating plate 20.

Meanwhile, the heat-transferring element 40 is upwardly projected by a predetermined height from the bottom of the container 10, and the heat-transferring element 40 is integrally formed from the bottom of the container 10 by means of a process such as die casting; The heat-transferring element 40 can be shaped as a tapered projection wherein the thickness of the tapered projection is getting smaller upwardly, or it can be shaped as a plurality of rings wherein the rings are coaxial and have different diameters from each other, or it can be shaped as a plurality of circular arc. Preferably, in order to maximize an area for heat-transferring, the heat-transferring element 40 can be provided with grooves of semi-circle shape or otherwise variable shapes on the circumferential surface of the rings

In particular, the fumigation apparatus according to the present invention is characterized in comprising a porous film 50 with a uniform thickness formed on an inner side surface and a bottom of the container 10 and on a surface of the heat- transferring element. That is, the porous film 50 is formed with a uniform thickness along the surfaces contacted with sulfur.

The porous film 50 has a plurality of minute holes formed by corroding the surfaces by means of acids such as hydrochloric acid and acetic acid, so that the heating area for sulfur can be more expanded by the osmotic action for absorbing sulfur through the minute holes.

Meanwhile, the container 10 can be provided with an accommodating part 60 for accommodating solid, powder, liquid chemicals or additional cartridge type container, which is separated from the part for putting sulfur therein, and the liquid chemicals such as insecticide, fungicide, antiseptic, repellent and the like has a melting or boiling point different from that of sulfur. The accommodating part 60 can be located at the center of the container 10 separately from the part for sulfur, or can be located at the outer part of the container 10 In particular, it is most preferable that the accommodating part 60 for solid, powder, liquid chemicals, is upwardly projected with a higher height than the other heat-transferring elements 40 as shown in Fig. 4, Fig. 5 is a plane cross-sectional view along A-A line of Fig. 4. Fig. 5 illustrates a construction having the heat-transferring element 40 and the porous film, which are partitions shaped in a plurality of rings or a plurality of circular arcs on concentric circles having different diameters from each other/ That is, a porous film 50 is formed on the surface of the heat-transferring element 40 shaped in a plurality of rings or arcs and on a bottom surface and an inner circumferential surface of the container 10. Thus, melted sulfur can be directly contacted with the porous film 50. Meanwhile, as shown in Fig. 6, the heat-transferring element 40 may have grooves of semi-circle shape or otherwise variable shapes formed on the circumferential surface of the element, so that the heat-transferring area can be maximized. Then, the porous film 50 can be formed on the circumferential surface thereof. Since the porous film 50 has a plurality of minute holes, the melted sulfur is filled therein and so raised upwardly by an osmotic action, whereby the liquid surface area exposed to atmosphere and the evaporation area can be more expanded. Meanwhile, Figs. 7 and 8 are diagrams illustrating the fumigation apparatus according to another embodiment of the present invention. The construction of the present embodiment includes a container 10 for storing the predetermined amount of sulfur therein; a heating plate 20 for heating a bottom of the container 10 to a predetermined temperature, which contacts with the bottom of the container 10; a heating means 30 for directly heating the heating plate 20; a heat-transferring element 40 which is formed with a predetermined height from the bottom of the container 10; and a porous film 50 formed with a uniform thickness along an inner surface and a bottom of the container 10 and along a surface of the heat-transferring element 40 upwardly projected from the bottom of the container 10, which is similar to the construction of the above-mentioned embodiment. This embodiment is characterized in that the fumigation apparatus comprises a temperature-controlling part 70 for controlling the heating temperature of the container 10 by rotating the container 10 and changing an area contacted between the container 10 and the heating plate 20, wherein a bottom of the container 10 and an upper surface of the heating plate 20 are divided into a plurality of partitions, and opposite surfaces of the respective partition are inclined by a predetermined degree. That is to say, the temperature-controlling part 70 has a rotating axis 71 and an axial groove 72 respectively formed on the center of the bottom of the container 10 and on the center of an upper surface of the heating plate 20 and. Outside the rotating axis 70 and the axial groove 72, an engagement groove 73 and an engagement projection 74 with larger diameters are formed so that they are engaged with each other. Surfaces outside the engagement projection and groove are partitioned into two or more partitions, and opposite surfaces of the partitions to be contacted to each other are respectively inclined in the same directions. The axial groove 72 and the engagement projection 74 are formed on the bottom of the container 10, and the rotating axis 71 and the engagement groove 73 are formed on the upper surface of the heating plate 20. The engagement projection 74 is formed higher than the engagement groove 73, and thus the surfaces outside the engagement groove 73 and the engagement projection 74 are distant from each other by the predetermined height (H) in case .the container is moved down to the maximum. Meanwhile, as shown in Fig. 9, in order to accommodate more liquid chemicals than a capacity of the accommodating part for liquid chemicals 60 and to prevent the liquid chemicals from spreading through the accommodating part for sulfur, a separate cartridge type container 80 for filling an insecticide or repellent is designed to be easily inserted and detached to/from the accommodating part for liquid chemicals 60. That is to say, the cartridge for liquid chemicals 80 has a similar outside diameter to an inside diameter of the accommodating part for liquid chemicals 60, and the cartridge also has a higher height than the heat-transferring element 40, which is a side wall of the accommodating part for liquid chemicals 60, thereby having a various size. Specially, an orifice of the cartridge for liquid chemicals 80 through which the chemicals are evaporated may have a small size in case of liquid chemicals with a high volatility, while it may have a large size in case of liquid chemicals with a low volatility.

It is preferable to prepare cartridges for liquid chemicals having a various size of the orifice 81. In addition, as shown in Fig. 10, the container 10, the heating plate 20 and the heating means 30 are placed in the protective cover 90 having a larger size than the outside diameter of the container 10. Here, a plural of vertical brackets 100 is formed at a predetermined height from the bottom of the protective cover 90, and the heating plate 20 engaged with the heating means 30 is mounted on the bracket 100. The heating plate 20 may be engaged fixedly with the bracket 200, or engaged detachably. The protective cover 90 is for protecting a worker from a hot surface of the container 10, and also for preventing heat loss escaped from the heated container 10 from being wasted. Meanwhile, an internal circumference surface of the protective cover 90 is distant from an outer circumference surface of the container 10 by a predetermined interval, and a ring shaped cartridge for liquid, solid or powder chemicals 110 is easily inserted detachably between the circumference surfaces, as shown in Fig. 11. The ring shaped cartridge for liquid chemicals 110 is for accommodating the insecticide, fungicide or repellent which have relatively low boiling point, so that the active ingredient can easily be evaporated with a small amount of convection heat energy produced from the container 10, and also prevents heat generated from the container 10 from being transferred to the outside. An operation of the present invention having the above structure is as follows. The present invention is provided to control pests in an airtight space such as a greenhouse, and it also has a function of insecticide and fungicide. In the present invention of the above structure, similarly to the prior art, a predetermined amount of sulfur is filled into the container 10, and a heating plate 20 is heated to a predetermined temperature by the heating means 30 to produce sulfur vapor. Here, the sulfur is heated up to a predetermined temperature and melted, and the melted sulfur is filled into minute holes of the porous film 50, which is formed in the container 10, and the liquid sulfur is drawn up, thereby providing a larger surface area for evaporating easily. That is, sulfur in the container 10 contacts the porous film 50, which has a uniform thickness on an internal circumference surface, a bottom and the heat- transferring element 40, and some heated and melted sulfur is absorbed into the porous film 50 by an osmotic action and drawn up and also heated, thereby making larger an area for evaporation. As the surface area of a liquid sulfur is enlarged, an area for evaporating sulfur vapor is enlarged that much, thereby generating more sulfur vapors through the enlarged evaporation area. In more detail, this invention includes the lateral surface inside the container, the bottom, and the porous film 50 formed by oxidizing the surface of the heat- transferring element 40, which is projected integrally upwardly from the bottom of the container 10, thereby absorbing the melted sulfur through the porous film 50 by an osmotic action, and lifting the melted sulfur to a higher level than a level of liquid sulfur to increase a surface area for heating sulfur. In other words, sulfur in the container 10 begins to be melted by heating, the melted sulfur is absorbed into the porous film 50 formed above the level of sulfur, thereby increasing considerably the evaporating area and producing more sulfur vapor. Table 1 shows exemplary comparison results between evaporation amounts of sulfur through the porous film 50 in the non-osmotic action type container and general container.

[Table 1]

Amount of evaporation of sulfur (g/100 hours)

The measurement shown in the table 1 is made at 13 ^°C of room temperature. As shown in the above Table, an evaporation amount of sulfur by osmotic action according to the present invention shows a wide difference of the evaporation amount in comparison with the amount in the general container of a bigger capacity. In addition, the present invention shown in the table 1 also shows a remarkable difference of the evaporation amount in comparison with non osmotic action type in the same condition, which was previously filed by the present applicant. Specially, as shown in the table, although a temperature for heating the container 10 by osmotic action according to the present invention is lower than others, this invention obtains more amount of evaporation. In addition, pesticide or repellent may be filled directly or additional cartridge type container in the accommodating part for liquid chemicals 60, which is isolated by the heat- transferring element in the container 10, and the evaporated substances performs a pest control, repellent action as well as disease control by the fumigation of sulfur. In the mean time, the substances, such as pesticide, fungicide or repellent may have a different boiling point from sulfur, and so the present invention has a temperature control means 70. The temperature control means 70 rotates the upper container 10 by an appropriate angle and controls an area which are contacted with an upper surface of the heating plate 20, thereby controlling temperature for heating the sulfur, pesticide, fungicide or repellent. In other words, when the container 10 is moved down to the maximum as shown in Fig. 7 and Fig. 8, the engagement projection 74, which is projected downwardly in the center of a lower surface of the container 10, is mounted in a contact state on a bottom of the engagement groove 73 of the heating plate 20, and an inclined lower surface except the engagement projection 74 is distant from an inclined upper surface of the heating plate 20 by a predetermined interval. This arrangement results from the structure where the engagement projection 74 of the container 10 is higher than the engagement groove 73 of the heating plate 20. When the heating plate 20 is heated in the above state, the accommodating part for liquid chemicals 60 with pesticide, fungicide or repellent is heated through the engagement groove 73 and the engagement projection 74 contacted with each other to perform controlling or repelling insect and fungus, and heat is also transferred to the inclined surfaces of the outside regardless of separation of the surfaces, thereby heating sulfur in a lower degree. The heating of the container 10 is for heating concentrically and evaporating only liquid chemicals in the accommodating part for liquid chemicals 60. Differently from the above, when the above container 10 is rotated as shown in

Fig. 12, the inclined lower surface of the container 10 is contacted widely with the inclined upper surface of the heating plate 20, and heat is transferred through the inclined surfaces well as the accommodating part for liquid chemicals 60 in the center, thereby melting sulfur as well as the insecticide, the fungicide and the repellent. Meanwhile, when the container 10 is rotated as shown in Fig. 13, it moves up glidingly along an inclined upper surface up to a minute height. Here, the bottom of the engagement projection 74 in the center is separated from the bottom of the engagement groove 73, and so heat is transferred only through the inclined surfaces where the bottom of the container 10 and the upper surface of the heating plate 20 contact with each other. Specially, as shown in Fig. 9, in case the cartridge for liquid chemicals 80 having a large internal volume is engaged detachably with the accommodating part for liquid chemicals 60 of the container 10, more liquid chemicals than the accommodating part for liquid chemicals 60 can be evaporated for a long time, thereby resulting an effective management and preventing the liquid chemicals from spreading through the accommodating part for sulfur. In addition, when a size of the orifice 81, through which the liquid chemicals in the cartridge 80 is evaporated, is chosen appropriately according to a boiling point or volatile rate of the liquid chemicals, an evaporation efficiency of the insecticide or repellent evaporated at a high temperature can be maximized. In addition, as shown in Fig. 10, the container 10 of the present invention is covered by the separate protective cover 90 to prevent unnecessary heat leakage and to prevent a worker from a bum through his carelessness. Specially, in the present invention as shown in Fig. 11, in case the ring shaped cartridge for liquid chemicals 110 is inserted detachably between the container 10 and the protective cover 90, as well as the accommodating part for liquid chemicals 60 of the container 10, convective waste heat generated from the container 10 is used, thereby evaporating the insecticide or repellent having a low boiling point and maximizing a heat efficiency. As above, the present invention includes the porous film 50 as a surface with sulfur in the container 10 to increase an evaporating surface area and decrease remarkably a heating temperature needed from the heating means 30. So, in the invention, a vaporization amount of sulfur is increased and any waste sulfur does not produced . In addition, in the present invention, liquid chemicals having a different melting point from that of sulfur such as pesticide, fungicide or repellent are applicable to the container separately or simultaneously, and so the invention may be used in many ways, and allows optimum control of temperature by rotating the container 10.

Industrial Applicability As described above, the present invention includes a multiple of the heat transferring element 40 which is formed from the bottom of the container 10 up to a predetermined height; and the porous film 50 which is formed on the internal circumference surface, the bottom of the container and a surface of the heat-transferring element 40, thereby increasing a contact area of sulfur with heat through the container and increasing an evaporation efficiency of sulfur. This increase of the contact area allows temperature for heating to be lower and prevents an accident of combustion resulting from heating sulfur at higher temperature. The present invention reduces power consumption for heating, and does not produce any waste sulfur to allow maintenance in harmony with environment. Specially, the invention further includes the accommodating part for liquid chemicals 60 holding the liquid chemicals such as pesticide, fungicide or repellent as well as a room for sulfur in the container, and so it can be used for a general use as well as a biological control to provide a maximum vaporization effect of the liquid chemicals by an exact temperature control.

Claims

What is claimed is: 1. A fumigation apparatus comprising a container which has an empty inner space with a predetermined volume for storing sulfur therein, of which an upper portion is open; a heating plate for heating the container to a predetermined temperature, which contacts with a bottom of the container; a heating means for heating the heating plate; a heat-transferring element which is upwardly projected by a predetermined height from the bottom of the container; and a porous film with a predetermined thickness formed on an inner surface and the bottom of the container and on a surface of the heat-transferring element.

2. The fumigation apparatus according to claim 1, wherein the porous film has many minute holes formed by eroding a surface of the heat-transferring element.

3. The fumigation apparatus according to claim 1, wherein the porous film is formed by oxidizing the surface of the heat-transferring element.

4. The fumigation apparatus according to claim 1 further including, in the center of the container, an accommodating part for liquid, solid or powder chemicals with pesticide, fungicide or repellent as well as an accommodating part for sulfur.

5. The fumigation apparatus according to claim 4, further including a cartridge for liquid chemicals having a larger accommodating volume which is inserted detachably to the accommodating part for liquid chemicals.

6. The fumigation apparatus according to 5, wherein the cartridge for liquid chemicals may have a different size of an orifice on its top, depending on a volatility of the liquid chemicals therein.

7. The fumigation apparatus according to claim 4, wherein a heat-transferring element forming the accommodating part for liquid, solid or powder chemicals is higher than the other heat-transferring elements.

8. The fumigation apparatus according to claim 1, wherein the container and the heating plate are covered by a protective cover, and they are distant from the cover by predetermined intervals on the downside and outside the container and the heating plate, and wherein a bottom of the heating plate is mounted on a plural of brackets which are formed at a predetermined height from a bottom of the protective cover.

9. The fumigation apparatus according to claim 8, wherein between an internal circumference surface of the protective cover and an outside surface of the container is detachably inserted a ring shaped cartridge for liquid chemicals to accommodate an insecticide, a fungicide or a repellent having a relatively low boiling point

10. The fumigation apparatus comprising a container which has an empty inner space with a predetermined volume for storing sulfur therein, of which an upper portion is open; a heating plate for heating the container to a predetermined temperature, which contacts with a bottom of the container; a heating means for heating the heating plate; a heat- transferring element which is upwardly projected by a predetermined height from the bottom of the container; a porous film with a predetermined thickness formed on an inner surface and a bottom of the container and on a surface of the heat-transferring element; and a temperature-controlling means for controlling a heating temperature wherein the bottom of the container and an upper surface of the heating plate, which are opposite to each other, are divided into a plurality of partitions, and opposite surfaces of the respective partition are inclined by a predetermined degree, so that the heating temperature can be controlled by a contact area between the container and the heating plate when the container is rotated by a predetermined degree.

11. The fumigation apparatus according to claim 10, wherein the porous film of the heat-transferring element 40 has minute holes by eroding the surface of the heat- transferring element.

12. The fumigation apparatus according to claim 10, wherein the porous film is formed by oxidizing the surface of the heat transferring element.

13. The fumigation apparatus according to claim 10, further including, in the center of the container, an accommodating part for liquid, solid or powder chemicals with pesticide, fungicide or repellent as well as an accommodating part for sulfur.

14. The fumigation apparatus according to claim 13, wherein a heat- transferring element including the accommodating part for liquid chemicals is higher than the other heat-transferring elements.

15. The fumigation apparatus according to claim 13, further including a cartridge for liquid or powder chemicals having a larger accommodating volume which is inserted detachably to the accommodating part for liquid chemicals.

16. The fumigation apparatus according to claim 15, wherein the cartridge for liquid or powder chemicals may have a different size of an orifice on its top, depending on a volatility of the liquid chemicals therein.

17. The fumigation apparatus according to claim 10, wherein the temperature- controlling means includes an axial groove and an engagement projection which is projected downwardly in the bottom of the container, the temperature-controlling means further including a rotating axis in the center and an engagement groove on the upper surface of the heating plate to make the groove to be engaged with the engagement projection, and surfaces outside the engagement groove and projection are divided into two more partitions which are inclined in the same direction to contact each other.

18. The fumigation apparatus according to claim 10, wherein the container and the heating plate are covered by a protective cover, and they are distant from the cover by predetermined intervals on the downside and outside the container and the heating plate, and wherein a bottom of the heating plate is mounted on a plural of brackets which are formed at a predetermined height from a bottom of the protective cover.

19. The fumigation apparatus according to claim 18, wherein between an internal circumference surface of the protective cover and an outside surface of the container is detachably inserted a ring shaped cartridge for liquid chemicals to accommodate an insecticide, a fungicide or a repellent having a relatively low boiling point.