ES2244354A1 - Indirect combustion dehydrator, for e.g. gypsum fabrication material, includes concentric chambers for simultaneous two-stage drying based on combustion gas heat - Google Patents

Abstract

An indirect combustion dehydrator for e.g. gypsum fabrication material has concentric inner, intermediate and outer chambers for simultaneous preliminary and final drying in the inner and outer chambers respectively. The rotary tubular system utilizes the gases flowing from an outer feed pipe, and the final drying is based on direct action of the combustion gases.

Description

Furnace with rotary tubular kettle system and indirect combustion for dehydration of the mineral destined to the manufacture of plaster and plaster or other materials.

Object of the invention

The object of the present invention refers to an oven, of the type called rotary fire pots indirect and cyclic intermittent loading and unloading, in which to perform dehydration of the material (plaster stone or the material that is in powder form), this is introduced into the inside of it, which in turn is inside the home that it wraps it and where combustion occurs, which incorporates a three chamber rotary tubular kettle system concentric

Specifically, the oven cooking system that the invention advocates, consists of an indirect combustion of intermittent action, the pot being prepared to achieve dehydration of the material in two simultaneous phases; one of pre-drying and other final dehydration, all  by incorporating the three mentioned cameras unified in the same oven, getting a considerable reduction in cooking times and energy use calorific with the consequent energy and cost savings of production.

Field of application of the invention

The field of application of the oven with system rotary tubular kettle and indirect combustion for dehydration of the ore destined for the manufacture of gypsum and plaster or other materials object of the invention is that of the industry dedicated to the construction of machinery and ovens in in general and specifically that of ovens for dehydration of ore in the manufacture of plasters and plasters or that of others materials.

Background of the invention

The problems that exist are well known on our planet because of air pollution produced by technological and industrial development (in particularly due to the deterioration suffered by the ozone layer). This pollution is produced by emissions into the atmosphere of CO2 (carbon dioxide) from the combustion of hydrocarbons of the industrial sector in general.

All this has forced the governments of the developed states to take measures to, where possible, reduce such contamination, such as agreements derived from Kyoto Protocol of 1997 of recent entry into force.

In today's ovens, although it has reached a high technological grade (among which recuperators are used of heat), these measures are not enough to take advantage of maximum said energy that goes directly to the atmosphere, with the consequent damage to the ozone layer.

Therefore research was necessary and innovation of ways to reduce fuel consumption employees without prejudice to production, as is the case with the The present invention, which, as will be described, has advantages functional that contribute to improve energy efficiency reducing pollution and providing a more system Economical and fast for the function that is intended.

Explanation of the invention.

Thus, with the present invention, it has been achieved the manufacture of an oven that substantially reduces the fuel consumption (gas, fuel oil, diesel or oil), basing its operation essentially on taking advantage of maximum calories produced by the combustion of fuels employees for that purpose.

With the new oven it is possible to reduce consumption in kilocalories necessary for dehydration of the mineral in the manufacture of plaster and plaster, of the order of between 30% and 50%, taking as reference the current ovens.

This reduction is achieved thanks to the design and configuration of the new oven in which dehydration is produces in two simultaneous phases, instead of performing a single load per dehydration cycle and cooking from completely raw material on each occasion as it came performing in current ovens, that is, given its configuration structural and mechanical, with the new furnace it is achieved that the material dehydration is carried out in two chambers independent but united in solidarity with each other, in which takes advantage of the same heat energy while accelerating the process, significantly reducing cooking times.

The new oven with tubular kettle system Rotary and indirect combustion for mineral dehydration intended for the manufacture of plaster and plaster or other materials, It consists basically of a metal structure forming a longitudinal tubular body, located horizontally, at whose ends it incorporates individual rings of rolling, being coupled concentrically and jointly to said tubular body and between said rings, two tubes of larger diameter, which rotate together with the main tube of rolling and they are attached to it and each other by suitable supports, forming a single block divided into three cameras

The first of these cameras or central camera is where the raw material is deposited.

The second is a receiving camera where deposit the material from the central chamber, during interval between one cycle and the next, and thus avoiding to mix the material that has received the treatment of pre-dried with the material you have already received the final dehydration treatment. Your mission, therefore, is retain the pre-dried material inside until that the oven has stopped rotating in the direction of discharge of the finished material

The third chamber is where the final dehydration process of the material that comes from the second chamber has already been pre-dried before In the first chamber.

In this way, the use of energy in The new oven object of the invention is made thanks to the configuration of its three concentric chambers through cycles that Repeat in the following sequence:

- In the first chamber or internal chamber, in the that primary dehydration is performed or pre-removed, combustion gases are introduced, through an outer conduction, since wrapping the whole of the three chambers is the combustion home where there is the maximum temperature, taking a tour of its interior and heating the raw material that houses up to a certain temperature.

- In the third camera or external camera in which final dehydration is performed, the material is received, then having passed through the second chamber or reception chamber, with the temperature that has been reached in the first chamber during the previous cycle, proceeding to finish the dehydration of the material (in this case the calories needed for the final dehydration come from home that wraps it where the maximum temperature is reached, through the sheet metal that forms its outer structure).

- The gases from this combustion are those that have been introduced through external driving directly in the first primary dehydration chamber before described, repeating the cycle again.

In furnaces known and used so far gases are expelled directly into the atmosphere or reused only for the material itself, which is done in independent intervals in which each time must be reached the right temperature starting from a totally raw material that once dehydrated must be extracted to give way to a new load, while the furnace of the invention takes advantage of said gases for the first phase of dehydration or pre-drying which means a significant saving of time and energy, since the final dehydration process is performs in less time having been pre-dried the material in the previous phase and at the same time that the final dehydration of the previous load.

That is to say, in rotation regime of the new oven and in the process of dehydration of the material, the central chamber goes dehydrating the material of a load by means of the flow of hot gases from the combustion home that reach your inside through an outer duct. The intermediate chamber or receiver of the pre-dried material is empty and the external chamber where the dehydration of the material ends contains the material of the previous load in the process of final dehydration, which is heated in turn by the calories that come from the combustion home radiated to the inside of it through the metal sheet that forms the outer tubular structure of said chamber.

During cooking intervals between cycles and the next one, the oven stops and changes its direction of rotation, proceeding to the emptying or discharge of the dehydrated material. To the same time the material coming from the central chamber that has received the pre-drying treatment, goes to the intermediate chamber where it is deposited until the end of Turn in the direction of discharge.

Once the cooked material has been unloaded and being the intermediate chamber full and the outer chamber empty, the oven is stops and changes its direction of rotation again, starting then a new cycle, in which this material deposited in the chamber intermediate passes to the final dehydration chamber leaving said empty chamber and simultaneously enters the central chamber a new load of raw material, giving way to a new firing of  pre-drying in the central chamber and dehydration Final in the external camera.

Additionally, so that the material can move inside the oven (since it works level and in position horizontal as a whole), the invention provides for the existence of some spirals and stirring blades inside the tubes that make up the cameras. These spirals and shovels are conveniently welded to the inner wall of the chambers.

Finally, the electrical installation of the new oven, has motion detectors, photocells, detectors flow, temperature probes and safety devices for protection of machinery as well as operators, whose information is collected by a PLC which offers total control and exhaustive about the plant, either manual or automatic. The installation also has a scada program for monitoring of temperatures, alarms, historical and state of the different devices

The new oven with tubular kettle system Rotary and indirect combustion for mineral dehydration intended for the manufacture of plaster and plaster or other materials represents, therefore, an innovative structure of structural and constitutive characteristics unknown up to now for this purpose, reasons that together with its practical utility, will provide sufficient grounds to obtain the privilege of exclusivity that is requested.

Description of the drawings

For a better interpretation of the invention, accompanies the present specification of some drawings in which a form of non-limiting example is illustrated realization of an oven with rotary tubular kettle system and indirect combustion for dehydration of the mineral destined to the manufacture of plaster and plaster or other materials subject to invention, according to the principles of the claims.

In these drawings:

Figures 1 and 2 show paths seen in front and side elevation respectively of the new oven object of the invention in which the different ones are appreciated externally parts that constitute it.

Figure 3 shows a sectional view longitudinal of the oven in which the integral parts are observed of its internal components and in which the route has been indicated that make the gases coming from the combustion chamber to the central pre-drying chamber.

Figure 4 also shows a view in cross section in this case of the oven in which also the route inside the gases coming from the combustion chamber to the central chamber of pre-drying

Figures 5 and 6, shows in greater detail paths seen in longitudinal and cross section respectively of the three chamber kettle.

Figures 7 to 9 schematically show the different phases of the path that the material to dehydrate performs during each charge cycle.

Description of an embodiment of the invention

A description will be made below. detailed set of functional parts of the new oven with rotary tubular boiling system and indirect combustion for dehydration of the ore destined for the manufacture of gypsum and plaster or other materials, referring to the drawings that are accompany, which are presented only as an example of possible realization and in which the different parts that understand with the references indicated below:

(M)

Rotating kettle constituted by the set of the three cameras.

(one)

Central Chamber

(2)

Intermediate chamber

(3)

External camera

(4)

Hoops rolling.

(5)

Lifting rollers

(6)

Gearmotor.

(7)

Cogwheel.

(8)

Material input hopper raw.

(9)

Inlet duct of material to the central chamber (1).

(10)

Endless feeder.

(eleven)

Central tubular support

(12)

Blades of the central tubular support (eleven).

(13)

Nozzles for the passage of the material and the gases from the central chamber (1) to the intermediate chamber (2).

(14)

Nozzles for the passage of the material and the gases from the intermediate chamber (2) to the external chamber (3).

(fifteen)

Receiver housing

(16)

Nozzles for the passage of the material of the external camera (3) to the receiving housing (15).

(17)

Endless material conveyor to Exterior.

(18)

Temperature control probe central chamber (1).

(19)

Temperature control probe external camera (3).

(twenty)

Burners

(twenty-one)

Fans

(22)

Combustion chamber.

(2. 3)

External structure of home.

(24)

Outside conduit pipe gases

(25)

Driving gas inlet to the central chamber (1).

(26)

Gas outlet pipe to Exterior.

(m)

Material in process of pre-drying

(m ')

Material in the process of dehydration final.

(m '')

Raw material

In this way, as can be seen in the accompanying figures, the furnace with rotary tubular kettle system and indirect combustion for dehydration of the ore destined for the manufacture of gypsum and plaster or other materials is basically formed by a structure, built entirely with conveniently reinforced metal materials, comprising a kettle (M) consisting of the set of three rotating concentric tubular bodies joined together by suitable supports and arranged horizontally formed by a central chamber (1) of substantially greater length, a chamber intermediate (2) and an external camera
(3).

Near its ends, the aforementioned camera central (1) incorporates two rolling rings (4) that together with the support rollers (5) facilitate the rotation of the kettle (M) in as a whole through the action carried out by the motor-reducer (6) on the gearwheel (7) that is coupled at one of its ends, said reduction motorbike being (6) governed by oven control devices and rotating in one way or another or stops depending on the needs of every moment of the cooking cycle.

The raw material is introduced through a hopper (8) in the central chamber (1) through a duct input (9) that incorporates an endless feeder (10). A support tubular (11) located in the center of said chamber and provided with layered blades (12) arranged radially, when turning the kettle they raise the material inside favoring their contact with the gases in the pre-drying phase that occurs in this camera.

The nozzles (13) allow the passage of the material pre-drying from the central chamber (1) to the chamber intermediate (2), subsequently passing through the nozzles (14) to the external chamber (3) where the process of final dehydration Once the cooking is finished, the material enters the receiving housing (15) through the nozzles (16) to be directed outside the installation through endless conveyor (17).

Both probes (18) and (19) located respectively in the central chamber (1) and in the external chamber (3) detect the temperature of the material, in the process of pre-drying in one and final dehydration in the another, for registration and control through devices relevant available to the oven.

On the other hand, as observed in the Figures 3 and 4, the action of the burners (20), endowed with their corresponding fans (21) intended to facilitate the combustion of the flame in the combustion chamber (22), which is in the lower part of the oven, under the kettle (M), in the interior of the structure of the home (23) properly coated internally of insulating material composed of refractory fiber, causes the heating of moving gases in motion ascending around the kettle (M) and are conducted through an outer pipe (24) towards the inlet conduit (25) to the inside the central chamber (1).

Inside this chamber, these gases they provide the necessary heat in the process of pre-drying of the material it contains, going through subsequently the different chambers through the nozzles (13), (14) and (16) towards the receiving housing (15) on which the tube (26) for the exit of gases to the outside, which, before expulsion into the atmosphere, will pass through a filter purifier particles

The sequence depicted in figures 7 to 9 schematically shows the different phases that are repeated in each cooking cycle, like this:

- In a first phase, when turning the oven and thanks to the circulation of gases, it occurs simultaneously the pre-drying of a load of material (m) in the central chamber (1) and the final dehydration of another portion of material (m ') in the external chamber (3) (Figure 7).

- In a second phase of the cycle, the kettle reverse the direction of rotation and discharge the material (m ') from the external chamber (3) to the receiving housing (15) and outside to through the nozzles (16), while the material (m) pre-drying of the central chamber (1) passes through from the nozzles (13) to the intermediate chamber (2) (Figure 8).

- Finally, the material (m) pre-drying passes from the intermediate chamber (2) to the external chamber (3) through the nozzles (14), at the same time as  a new load of raw material (m '') is introduced into the chamber center (1) through the feeder auger (10) located in the inlet duct (9) of said chamber to restart the cycle (Figure 9).

Describe sufficiently the nature of the The present invention, as well as how to implement it, is it states that, within its essentiality, it may be taken to the practice in other embodiments that differ in detail from the one indicated by way of example, and which will reach also the protection that is collected as long as it is not altered, change or modify its fundamental principle.

Claims (4)

1. Furnace with rotary tubular kettle system and indirect combustion for the dehydration of the ore destined for the manufacture of gypsum and plaster or other materials, of the type of so-called cyclic intermittent loading and unloading, in which to perform the dehydration of the material (gypsum stone or whatever material), it is introduced inside it in powdery form, which comprises a structure constituted by a cylindrical furnace with a horizontal axis that extends inside the home that wraps it, equipped with its ends of rolling rings that rotates by means of the action that a motor reducer performs on a cogwheel coupled at one of its ends characterized by comprising a kettle (M) constituted by the set of three rotary concentric tubular bodies joined together by suitable supports and arranged horizontally that form a central chamber (1) of substantially greater length, a chamber in termediate (2) and an external chamber (3), in which the kettle (M) is prepared to achieve dehydration of the material in two phases that take place simultaneously; one of pre-drying in the central chamber (1) by taking advantage of the combustion gases that are conducted from the combustion chamber (22) through an outer pipe (24) towards the inlet conduit (25) inside of said central chamber (1), and another one of final dehydration in the external chamber (3) by means of the direct action of the gases produced in the combustion chamber (22) that circulate through the surrounding structure of the home (23). 2. Furnace with rotary tubular kettle system and indirect combustion for the dehydration of the mineral destined for the manufacture of gypsum and plaster or other materials, according to claim 1, characterized in that by inverting the kettle (M) the direction of rotation, discharges the material already dehydrated from the external chamber (3) to the receiving housing (15) and through the nozzles (16) is directed outside the installation by means of a conveyor auger (17), at the same time as the pre-dried material of the central chamber (1) passes through the nozzles (13) to the intermediate chamber (2). 3. Furnace with rotary tubular kettle system and indirect combustion for dehydration of the ore destined for the manufacture of gypsum and plaster or other materials, according to claims 1 and 2, characterized in that the material of the intermediate chamber (2) passes through from the nozzles (14) to the external chamber (3) at the same time that a new load of raw material is introduced through the inlet conduit (9) through the feeder auger (10) to start a new cooking cycle. 4. Furnace with rotary tubular kettle system and indirect combustion for the dehydration of the mineral destined for the manufacture of gypsum and plaster or other materials, according to claims 1 to 3, characterized in that said said kettle (M) is suitable for receiving in the central chamber (1) by means of an inlet conduit (9) incorporating a feeder auger (10) the raw material through a hopper (8), there being in the center of said central chamber (1) a tubular support (11) ) provided with radially arranged blades (12) that rotate the pot by raising the material inside and favor the action of the pre-drying phase of the gases on the material, and because both probes (18) and (19) located respectively in the central chamber (1) and in the external chamber (3) detect the temperature of the material, in the process of pre-drying in one and of final dehydration in the other, for its registration and control by means of the relevant devices that dis put the oven.