Patent Application
20110017190
As it is evident, the sustained growth of economy in Chile has led to a permanent increase of the energy demand. However, we know that the energy supply has been hindered by the country's lack of self-supply; its dependence on other countries has been one of its main problems, especially in respect of natural gas supply from Argentina.
Once the natural gas gasifying plant in Quintero starts operating, it will certainly permit a greater energy supply, although it is known that a higher cost of the energy will irremediably exist.
The problem inherent in the energy supply for domestic and commercial use has been most sensitive, since it involves an important social component. The energy destined to heating, food cooking and hot water supply certainly does not permit any interruption. In this scenario we could think that one of the natural and logical alternatives to be applied are renewable energies, such as firewood and biomass, which due to the diversity of climates could represent a significant alternative, where the Chilean central and south zones—having the greatest forest potential for wood production—are found, in addition to the historical culture of use of firewood ranges and stoves. As a consequence, mention is made of the problem of environmental pollution affecting very important cities of our country, such as Santiago, Rancagua, Chileán, Temuco, Osorno and others.
In effect, for over a decade the goodness of double combustion chamber firewood stoves appeared to be the solution, since everything suggested that by being most efficient they emit less contaminants into the external environment; however, everybody knows that there is a major variable, which is difficult to control by the agencies entrusted with environmental pollution matters, such as the need to use firewood suitable for heating purposes that has a low humidity content (under 20%). For this reason, it is of little advantage to have a stove manufactured according to a good technology if the wood is very humid; therefore, an excessive rise of the environmental pollution level is produced, since no practical regulations force the consumers to use only wood with 20% humidity or less.
In the practice, users can buy firewood in the informal market at a lower cost, but without its fitness for heating purposes being duly guaranteed. According to statistics delivered by CONAMA (the National Environmental Commission), it is estimated that during the year 2006 over 600 tons of PM 10 particulate material were discharged in Santiago, which is attributable to the use of firewood for heating and food cooking; these contamination levels are similar to those emitted by the industry and the overall collective transportation system of the city.
According to CONAMA, in 2006 over 70,000 firewood stoves were installed in Santiago and this figure would exceed one million in the country as a whole. A very strong expansion level has been projected and it could possibly reach three million firewood stoves by the year 2020. The reasons behind this expansion are the attraction and coziness offered by open fire stoves, in addition to their considerable heating capacity; however, their main attractive lies in their low operating cost; according to studies performed by Universidad Austral de Chile, firewood heating can be up to 14 times less expensive than electricity, 9 times cheaper than gas and almost 8 times cheaper than oil.
Firewood represents 17% of the energy consumption in Chile.
The market for firewood appliances in Chile is as follows:
(a) Yearly sales of double chamber combustion stoves: 70,000 units at an average unit value of CH$150,000.—
(b) Yearly sales of firewood ranges: 80,000 at an average value of CH$ 140,000.—
The present disclosure provides an appliance that uses biomass as fuel, equipped with closed combustion chamber, which incorporates a fuel feeding system in the form of briquets made of pressed sawdust using a high tonnage press. This fuel has been designed for the appliance according a specific geometric shape and dimensions, which is loaded to the stove around the combustion chamber. The fuel drops by gravity into the lower portion of the heater; next, each briquet is raised through the side portion of the supporting structure of the appliance by means of an internal conveyor.
The movement of the fuel (briquets) conveyor is performed by a stepper electric motor, i.e. the motor feeds the briquets one by one into the fuel chamber according to the heating needs of the environment by means of a thermoelectric control mechanism.
Characteristics of the present invention include the following:
(a) TO ESTABLISH A SINGLE AND REGULAR FUEL. The combustion chamber is closed in the front part and the user has no direct access to it, as it is now the case with all firewood stoves; it can be provided with a glass window that only permits to see the fire inside the chamber. In respect of the chamber, the appliance can only operate with a predefined fuel and not in the way the user commonly proceeds today, wherein very humid wood can be used without controlling the size and load of the combustion chamber. The briquets are produced according to predefined standards of humidity, density, dimensions and raw material involved. This fuel can be sold in the formal market inside a suitable packing that maintains the original humidity content, preferably not higher than 20%.
(b) AUTONOMY OF THE APPLIANCE. The standard strove considers a briquets transportation circuit that permits to load the unit with about 20 briquets of approximately 500 grams each, i.e., a 10 kg load inside the stove. If we consider an average consumption of 1.5 kg per hour, this means an estimated autonomy of 6 to 7 hours. In other words, the user can load its stove when going to bed and maintain the heating throughout the night.
(c) GREATER HEATING EFFICIENCY. In the use of this heating invention, the appliance can incorporate a turbine to drive the surrounding environmental air through the hot external part of the combustion chamber and thereby increasing the radiation efficiency of the heater; in other words, the heating capacity is comparatively increased in a shorter time as compared with the conventional firewood stoves equipped with single or double combustion chamber.
(d) VARIED APPLICATIONS. This appliance can have diverse applications; e.g., aside from heating, it can be used in firewood ranges where the stepper motor is substituted with a direct manual system for driving the briquets step by step inside the combustion chamber. In this way, the food cooking speed can be controlled according to the needs and the time availability of the user.
The stove can also be used to heat water in commercial and industrial boilers.
The appliance can be provided with a ceramic glass in its front part, so that the user can see the intensity of the fire, although access to the stove by introducing directly the fuel into the chamber is not possible, according to the principles already indicated for this invention.
In view of the foregoing, the present disclosure provides a technical and practical solution that permits to control the fuel load to the stove, a feature that has not been contemplated in the current units equipped with combustion chamber through radiation; in this way, the aspect of environmental pollution can be controlled, especially in the cities already referred to in this specification.
The client can enjoy autonomy, inasmuch as he/she is not permanently concerned with the introduction of firewood to the heater in order to avoid its becoming extinguished.
For a better understanding of the characteristics and advantages of this invention, by way of complement, a number of drawings are enclosed, which are of an illustrative and not restrictive character, where:
With reference to
With reference to
With reference to
Said conveyor (5) may correspond to a chain mechanism equipped with devices for guiding the briquets (2), being driven by toothed pinions made of steel or other heat-resistant material; the pinions are connected by means of an axis made of steel or other suitable material.
In the normal operating phase, once the stepper motor (4) is driven by means of a thermoelectric signal, the following simultaneous movements are produced:
1. The pitch sheave (3) effects one step.
2. The upper rotary gate (9) opens and a briquet falls into the chamber (8).
3. The conveyor (5) effects one pitch movement.
Once the briquets loading inside chamber (8) is complete and the respective motor (4) stops, the upper gate (9) closes and the pitch sheave (3) also stops.
Said ignition lid (6) can be opened to a greater or lesser extent in order to permit the entry of a greater or smaller air flow into the combustion chamber (8).
Between the combustion chamber (8) and the briquets compartment in the heater supporting structure (16) a thermal insulation layer (17) has been installed, with the object of avoiding an overheating in the briquets storage zone.
Said ashtray (15) can consist of a metallic pan for retaining the ash, from which ash can be eventually extracted by the user for its elimination.
| Number | Date | Country | Kind |
|---|---|---|---|
| 3611-2007 | Dec 2007 | CL | national |
