DE102004039386A1 - Boiler has preheating mechanism that varies warmth of vegetable oil using cooling agent - Google Patents

Abstract

A combustion chamber is defined by a cooling agent jacket (21) in a housing (10). Vegetable oil is supplied to a burner (23) through a supply line (24). A preheating mechanism (30) changes the warmth of the vegetable oil using the cooling agent. The preheating mechanism is arranged proximate the upper wall (25) of the cooling agent jacket.

Description

The The invention relates to a boiler for the combustion of liquid fuels according to the preamble of claim 1 and a method for Operation of the same.

Such a boiler is for example from the DE 190 25 729 A1 known. This boiler works with high efficiency at very low temperatures of the exhaust gases and relatively high temperatures of the heat exchange medium (water).

Want not fossil fuels but renewable fuels especially vegetable oil, especially rapeseed oil burn, so it comes in particular for longer storage times of the rapeseed oil to difficulties when feeding the oil to the burner, during the evaporation of the oil in the burner and during combustion even.

Of the Invention is based on the object, a boiler of the beginning to show that the burning of vegetable oil, in particular of rapeseed oil is improved. Furthermore, it is the object of the present invention to show a corresponding procedure.

These Task is by a boiler according to claim 1 or a Method according to claim 12 solved.

Especially the object is achieved by a boiler for the combustion of liquid fuels, comprising a housing or the like, heat-insulating Umman telung, a combustion chamber with a coolant jacket and a connected Burner, a supply line for supplying the fuel to the burner, the fuel being vegetable oil, especially rapeseed oil is and the supply line designed as a preheater Line section includes, in the vicinity of the coolant jacket for replacement of heat from the coolant to the vegetable oil is appropriate.

One essential point of the invention is that a preheating of vegetable oil takes place before this is led to the burner. This succeeds not only to achieve a lower viscosity of the vegetable oil, what the sputtering process It is advantageous, it is also the vegetable oil through the preheating one higher and more easily ignitable temperature brought.

Preferably is the preheating device on or near a top wall of the coolant jacket appropriate. This can ensure that the highest within of the heat exchanger circuit prevailing temperature for heat exchange to disposal stands.

The preheater is preferably opposite the sheath is thermally insulated, so that the vegetable oil at substantially exactly the temperature of the coolant remains.

The preheater is preferably tank-shaped formed and has a relative to the supply line considerably extended cross section. This will ensure that the vegetable oil is in the range the preheating device has a long residence time. Due to this high residence time is not only ensures that the temperature present in the coolant indeed is achieved, but also physical / chemical processes in the vegetable oil in motion brought, which ensure improved combustion. For this belongs also the cancellation of changes in the structure of vegetable oil through longer Storage. The volume of the preheater is preferably such that an amount contained in it of vegetable oil a need of the burner for at least half an hour, preferably 10 hours, especially preferably equal to about one day. By this not insignificant Volume of the tank-shaped preheater the o.g. Processes favored considerably. Another improvement can be achieved by that in the preheater deflectors or the like means of extension of the flow path of vegetable oil are attached. This essentially depends only on that each in the preheater introduced Subset of vegetable oil flows through the preheating with the same residence time, so that no Residual quantities in the preheater but there are no "shortcuts" to exist which the subsets of vegetable oil in less time the preheating can flow through.

Preferably are the preheating devices divided into at least two subsections, which at different Places to absorb heat the coolant are attached. This results in an even with uneven heating of the coolant safe preheating of vegetable oil.

The preheaters are preferably at an upper area, preferably in the area from beveled Upper edges of the coolant jacket attached with formation of triangular cross-sections. Thereby on the one hand an optimal design of the combustion chamber is ensured saved on the other place, since the housing of the boiler in cubic Shape can persist.

It is provided a pumping device in the supply line, which is formed and attached is controlled, that a complete filling of the preheater is guaranteed at a first start-up or after restarting after servicing the boiler. This improves the further operation.

Preferably is a (openable for cleaning) Filter device in the supply line between the preheater and the burner attached. In this area, which is traversed by the preheated vegetable oil, can very fine filter devices are provided without the Pressure drop over the filter would be too big.

The preheater is preferably formed and mounted so that the vegetable oil with a Temperature of at least 60 ° -80 ° Celsius supplied to the burner becomes. This temperature of vegetable oil has become protracted Try to be particularly cheap exposed.

to procedural solution of above-mentioned Task is a method of operating a boiler with Vegetable oil preferably rapeseed oil shown, wherein the vegetable oil before feeding to a burner over a period of at least 0.5-24 h is warmed up. The resulting advantages have already been described above.

following Become embodiments of the Invention explained in more detail with reference to figures. Show here

1 a schematic sectional view of an embodiment of the invention,

2 a partial section of another embodiment of the invention in a view similar to the 1 and

3 a front view of the embodiment according to 2 ,

In The following description will be for the same and the same Parts used the same reference numerals.

At the in 1 the embodiment shown is a boiler, as he himself from the DE 100 25 729 A1 is known. This boiler has a housing 10 on, in which a combustion chamber 20 is arranged in the upper area. The combustion chamber 20 is from a coolant jacket 21 surrounded, wherein usually water is used as the coolant. At the housing 10 is a burner housing 23 ' fastened, its burner 23 in the combustion chamber 20 sitting. The air supply to the burner 23 happens via an air supply line 13 ,

The hot gases are passed over the coolant jacket 21 as well as heat exchangers 22 cooled. The cooled exhaust gas is passed through an exhaust pipe 11 with a suction fan 12 aspirated. Forming condensate is via a condensate drain 14 dissipated.

The supply of vegetable oil, especially rapeseed oil is done via a supply line 24 , which are located in front of the mouth of the burner housing 23 ' to a tank-shaped preheater 30 extended, on a top wall 25 of the coolant jacket 21 is mounted. In this way it is guaranteed that over the line 24 supplied oil at an extremely low flow rate through the preheater 30 flows and thereby assumes its temperature due to the heat exchange to the coolant, before the oil in the burner 23 is burned. Furthermore, the preheating device 30 opposite the housing 10 heat insulated, so that the heat absorbed is not dissipated to the outside and the housing 10 has on its outer wall substantially room temperature and not the coolant temperature of 60 ° -80 ° Celsius. Due to this slow heating and the simultaneous prolonged keeping warm of the vegetable oil, its fine-structure is favorably influenced (for combustion).

The in the 2 and 3 embodiment of the invention shown differs from the 1 first in that the preheating device is divided into two tank-shaped lines 30 and 30 ' which are formed with a substantially triangular cross-section and in the region of bevelled upper edges 26 . 26 ' of the coolant jacket 21 or the correspondingly shaped combustion chamber 20 are arranged. On the one hand, this construction saves space, on the other hand, there is an extended "line", wherein this line extension can be further increased by that within the preheater 30 . 30 ' deflecting 31 be attached. This also ensures that no dead zones arise in which the vegetable oil lingers longer while other parts with (too) high flow rate to the burner 23 reach.

For filling the preheater 30 . 30 ' is a pump 27 provided, which at a first start of the device, the preheating 30 . 30 ' filled in such a way that essentially no air remains there.

The preheated vegetable oil reaches the burner 23 over a filter 28 that can be opened from the outside for cleaning purposes.

10

casing

11

exhaust pipe

12

aspirator

13

air supply

14

condensate drain

20

combustion chamber

21

Coolant jacket

22

heat exchangers

23

burner

23 '

burner housing

24 24 '

supply line

25

upper wall

26 26 '

top edge

27

pump

28

filter

30 30 '

preheater

31

deflecting

Claims (12)

Heating boiler for the combustion of liquid fuels, comprising a housing ( 10 ) or the like heat-insulating jacket, a combustion chamber ( 20 ) with a coolant jacket ( 21 ) and a connected burner ( 23 ) and a supply line ( 24 ) for supplying the fuel to the burner ( 23 ), characterized in that the fuel is vegetable oil, in particular rapeseed oil and the supply line ( 24 . 24 ' ) as a preheating device ( 30 ) formed in the vicinity of the coolant jacket ( 21 ) is attached to the exchange of heat from the coolant to the vegetable oil. Heating boiler according to claim 1, characterized in that the preheating device ( 30 . 30 ' ) on or near a top wall ( 25 ) of the coolant jacket ( 21 ) is attached. Heating boiler according to one of the preceding claims, characterized in that the preheating device ( 30 . 30 ' ) opposite the casing ( 10 ) is thermally insulated. Heating boiler according to one of the preceding claims, characterized in that the preheating device ( 30 . 30 ' ) is tank-shaped and one opposite the supply line ( 24 . 24 ' ) has significantly expanded cross-section. Heating boiler according to one of the preceding claims, in particular according to claim 4, characterized in that the volume of the preheating device ( 30 . 30 ' ) such that an amount of vegetable oil contained in it meets a burner ( 23 ) for at least half an hour, preferably for at least 10 hours, more preferably for at least one day. Heating boiler according to one of the preceding claims, in particular according to one of claims 4 or 5, characterized in that in the preheating devices ( 30 . 30 ' ) Deflection devices ( 31 ) or the like means for extending a flow path of the vegetable oil are attached. Heating boiler according to one of the preceding claims, characterized in that the preheating devices in at least two sections ( 30 and 30 ' ) and these are mounted at different locations for receiving heat from the coolant. Heating boiler according to one of the preceding claims, characterized in that the preheating devices ( 30 . 30 ' ) at an upper region, preferably in the region of bevelled upper edges ( 26 . 26 ' ) of the coolant jacket ( 21 ) are attached to form triangular cross-sections. Heating boiler according to one of the preceding claims, characterized in that a pumping device ( 27 ) in the supply line ( 24 . 24 ' ) and designed such that upon initial or re-operation of the boiler, a full charge of the preheating devices ( 30 . 30 ' ) is guaranteed. Heating boiler according to one of the preceding claims, characterized in that a filter device ( 28 ) in the supply line ( 23 . 23 ' ) between the preheater ( 30 . 30 ' ) and the burner ( 23 ) is attached. Heating boiler according to one of the preceding claims, characterized in that the preheating device ( 30 ) is designed and installed such that the vegetable oil at a temperature of at least 60 ° C to 80 ° C the burner ( 23 ) is supplied. Method for operating a boiler with vegetable oil, preferably with rapeseed oil, characterized in that the vegetable oil before being fed to a burner via a Period of at least half an hour, preferably at least 10 h, especially preferably heated from 24 h.