RU101789U1 - ELECTRIC FURNACE FOR FIRING VERMICULITE CONCENTRATES - Google Patents

Abstract

 An electric furnace for roasting vermiculite concentrates, containing flat baking sheets made of refractory material, mounted at an angle to each other, equipped with electric heaters located on the surface of the baking sheets under the covers, characterized in that the furnace further comprises a housing and perforated suction tubes fixed longitudinally in relation to the upper end parts of the baking sheets and the hopper-precipitator with an exhaust fan.

Description

The utility model relates to the field of building materials, namely, to technological equipment for the production of expanded vermiculite, used as a heat-insulating material in construction and a porous aggregate for lightweight concrete and mortar.

A known technological complex and a furnace for firing vermiculite (patent No. 47082, IPC ⁷ F27B 15/00 published on 08/10/2005, BI No. 22), comprising a firing furnace and a screen for fractionating vermiculite concentrate, mounted on a multi-section hopper for sorted concentrate and a hopper with a roll a feeder placed under a multi-section hopper that feeds fractionally sorted concentrate into the furnace. The furnace is made in the form of flat baking sheets made of refractory material, installed at an angle relative to each other, which ensures that the raw material is poured during firing from one to the other, while the baking sheets are equipped with electric heaters located on the surfaces of the baking sheets.

Common features of the known analogue with the claimed utility model are the oven itself, flat trays made of refractory material, mounted at an angle to each other and equipped with electric heaters located on the surface of the trays.

The disadvantage of the technological complex and the furnace for firing vermiculite is the inability to isolate finely dispersed (dusty) vermiculite, which is formed during firing during expansion and separation of particles of vermiculite, due to which, due to dust, the quality of the main product, expanded vermiculite, deteriorates and the loss of finely dispersed vermiculite, which is valuable raw material for the production of building mixtures, fire retardant paints and coatings.

Known furnace for firing vermiculite (options) [RF patent No. 85993, IPC F27B 15/00 (2006.01), published 08/20/2009, BI No. 23], including baking sheets made of refractory material, installed in relation to each other at an angle providing the pouring of raw materials during the firing process from one to the other, and equipped with electric heaters located on the surface of the baking sheets, the first two baking sheets are installed at the same level at an angle to each other with the possibility of pouring from each of them onto the third and subsequent lower baking sheets.

Common features with the claimed utility model are the oven itself, including baking sheets made of refractory material, installed in relation to each other at an angle to ensure that the raw material is poured during firing from one to the other, and equipped with electric heaters located on the surface of the baking sheets, the first two the baking sheets are installed at the same level at an angle to each other with the possibility of pouring from each of them onto the third and subsequent lower located baking sheets.

The disadvantage of the furnace for burning vermiculite is the inability to isolate finely dispersed vermiculite, which is formed during firing during expansion and separation of particles of vermiculite, resulting in deterioration of the quality of the main product - expanded vermiculite and the loss of finely dispersed vermiculite, which is a valuable raw material for the production of building mixtures, flame retardant paints and coatings .

As a prototype, an electric furnace for roasting vermiculite concentrates was selected (RF patent No. 2351862, IPC F27B 9/00 (2006.01), published April 10, 2009, BI No. 10), including flat baking sheets made of refractory material and installed at an angle to each other equipped with electric heaters located on the surface of the baking sheets, the baking sheets are provided with lids, and electric heaters are placed under the covers on the surface of the baking sheets.

The disadvantage of an electric furnace for firing vermiculite concentrates is the impossibility of separating finely dispersed vermiculite, which is formed during firing during expansion and separation of particles of vermiculite, resulting in deterioration of the quality of the main product, expanded vermiculite, and the loss of finely dispersed vermiculite, which is a valuable raw material for the production of building mixtures, fire retardant paints and smears.

During the production operation of such furnaces, it was found that during firing, expansion and separation of vermiculite particles occurs, accompanied by the release of a significant amount of finely dispersed vermiculite (vermiculite dust). The finely dispersed material is in the general array of expanded vermiculite (the main product). Filling intergranular voids, finely dispersed material increases the bulk density of the main product, worsening its quality.

The objective of the claimed utility model is to expand the arsenal of technical means aimed at achieving a technical result.

The technical result of the utility model is to improve the quality of the main product (expanded vermiculite) by isolating finely dispersed vermiculite from the total array during the firing process and obtaining additional volumes of finely dispersed vermiculite, which is a valuable raw material.

The specified technical result is achieved in that the electric furnace for roasting vermiculite concentrates, containing flat baking sheets made of refractory material and installed at an angle to each other, equipped with electric heaters located on the refractory surface of the baking sheets under the covers, further comprises a precipitating hopper with an exhaust fan , housing and perforated suction cups fixed in the housing longitudinally with respect to the upper end parts of the baking sheets.

In the working space formed by the refractory surface of the baking sheet and the lid, due to electric heaters, high temperature is created, causing the vermiculite concentrate to swell and the separation of vermiculite particles, accompanied by the release of a significant amount of finely dispersed vermiculite. Due to the high temperature, the air in the working space is heated and rushes up to the upper end parts of the baking sheets, involving the separated particles of finely dispersed vermiculite. Through the end parts of the baking sheets with lids, finely dispersed material is ejected from the working spaces. Thus, the main product (expanded vermiculite) during firing, pouring from one baking sheet to another, rolls and accumulates in the bunker of the main product, and finely dispersed vermiculite is ejected by the flow of heated air through the end parts into the area where the perforated suction pumps are located, where due to the vacuum created by the exhaust by the fan of the precipitating hopper, it is sucked by them and enters the precipitating hopper through pipelines.

That part of finely dispersed vermiculite that did not get into the perforated suction cups settles in the bottom of the tray for finely dispersed vermiculite and is sucked in by the perforated suction cup placed in it.

Distinctive features of the claimed utility model from the prototype is the presence of a housing and perforated suction cups mounted longitudinally in relation to the upper end parts of the baking sheets with lids and a precipitating hopper with an exhaust fan, which proves the compliance of the claimed utility model with the patentability condition “novelty”.

Figure 1 shows a diagram of an electric furnace for firing vermiculite concentrates.

Figure 2 shows the layout of the perforated suction device relative to the end of the pan and the heaters on the surface of the refractory base in the firing space (view A, the cover is conditionally removed).

An electric furnace for firing vermiculite concentrates contains a feeder-dispenser 1, housing 2, a hopper for the main product (expanded vermiculite) 3 and a tray for finely dispersed material 4. Perforated suction devices 5 are placed longitudinally at the upper end parts of the baking sheets in the inner space of the housing 2. Perforated suction cups 5 are connected to pipelines 6 (indicated by a thick line) connected to the hopper-precipitator 7, on which an exhaust fan 8 is installed, which ensures discharge in the hopper-precipitator 7 and in the perforated suction cups 5. The metering feeder 1 is in communication with the upper counterflow 9 .

The baking sheet has a working space 10 formed by a lid 11 and a refractory surface 12. Inside the working space 10 on the refractory surface 12 there are heaters 13 made of nichrome and secured by washers 14 on insulators 15 mounted on mounts 16.

The heaters 13 are fixed by washers 14 and placed on the refractory surface 12 with a certain step r, Fig.2. It also shows the position of the perforated suction device 5 relative to the end of the pan. The width of the refractory surface B depends on the number of heaters 13 and the pitch of their placement r.

Pipelines 6 connected to perforated suction devices 5 are held by fasteners 17.

An electric furnace for firing vermiculite concentrates works as follows.

Vermiculite concentrate from the hopper of the feeder-dispenser 1 enters through estrus 9 into the working spaces 10 of the upper and subsequent baking sheets, where it is fired (expanded). In the working spaces 10 of the baking sheets formed by the covers 11 and the refractory bases 12, due to the heaters 13 connected to the electric network (not shown in FIGS. 1 and 2), a high temperature of ~ 750 ° C is created, which is necessary for the expansion of vermiculite concentrate. Due to the high temperature, the air in the working spaces 10 heats up and, becoming less dense than the air outside the working spaces 10, rises upward, forming an air temperature draft. Swelling is accompanied by the formation of finely dispersed material, which is removed from the working spaces 10 by the air flow formed by the temperature traction through the upper end parts of the baking sheets. Here, perforated suction nozzles 5 connected longitudinally to the end parts of the trays connected to the pipelines 6 held by the fasteners 17 suck in finely dispersed vermiculite. The air flow generated by the discharge in the hopper-precipitator 7, pipelines and perforated suction pumps 5, formed by an exhaust fan 8, carries fine vermiculite into the hopper-precipitator 7.

Getting into the large space of the precipitating hopper 7, the air flow sharply loses speed and particles of finely dispersed vermiculite fall down and accumulate in the precipitating hopper 7.

That part of finely dispersed vermiculite that did not get into the perforated suction cups 5 settles in the bottom of the tray 4 and is also absorbed by the perforated suction cup 5 placed in it.

Ultimately, finely dispersed vermiculite formed during expansion accumulates in the precipitating hopper 7, and the main product thus purified (expanded vermiculite), which does not contain finely dispersed components, accumulates in the main product hopper 3.

Thus, the technical result of the utility model is achieved - improving the quality of the main product (expanded vermiculite) by isolating finely dispersed vermiculite from the total mass during firing and obtaining additional volumes of finely dispersed vermiculite, which is a valuable raw material.

Claims (1)

An electric furnace for roasting vermiculite concentrates, containing flat baking sheets made of refractory material, mounted at an angle to each other, equipped with electric heaters located on the surface of the baking sheets under the covers, characterized in that the furnace further comprises a housing and perforated suction tubes fixed longitudinally in relation to the upper end parts of the baking sheets and the hopper-precipitator with an exhaust fan.