FR2694375A1 - Waste incinerator furnace - has alternative rotary or fixed primary hearths and main fixed hearth both with burners and square section scrapers removing ash - Google Patents

Abstract

The incinerator loader (2) and burner (3) lead to a rotary hearth (1) opening out in the final static combustion chamber (4), above a sole plate (5). The final chamber has another burner (6) and primary air entries (7,8), with an upper post combustion chamber (13). Square section scrapers (11) push cinders over the sole plate towards an exit (12) to the ashpan. The rotary hearth may be replaced by a static primary hearth, with sole plates and pokers, for certain waste. The pokers may be several staggered metal or refractory blocks of square or rectangular section, close mounted. ADVANTAGE - Allows regulated combustion with non polluting fumes or odour. Simple construction, for humid waste, with minimum slag.

Description

The present invention relates to a multi-purpose incinerator for the destruction of household waste, hospital waste, organic waste or industrial waste under economic, regulatory and non-polluting conditions.

 There are currently two common techniques for destroying solid waste.

On the one hand static hearth or rack ovens and on the other hand rotary or oscillating hearth ovens
The advantages and disadvantages of these techniques are well known Static ovens require complex and expensive devices to ensure the progression of waste in the hearth, over a relatively large distance between the loading orifice and that of ash removal, while that the rotary ovens which ensure this progression simply and easily cause very high rates of unburnt in the chews because of the difficulty of sending combustion air into the mass of waste
The present invention makes it possible to produce a simple oven, of reduced cotttt, reliable and economical to operate while being in accordance with current requirements.
For this, it uses in combination and improving them, using known techniques, which makes it possible to avoid the drawbacks of each of the solutions and to obtain an efficient, simple and economical oven.
The + our 1 according to the invention consists of a primary rotating hearth, designed and produced according to the principle of known rotary or oscillating fors, followed by an end of static combustion chamber, equipped with a specific ringing device and flowing ash to the ashtray
During each loading, the waste falls into the rotating drum or they undergo the usual phases of pyrolysis and incineration progressively along the drum under the effect of its rotation
When they reach the end of the drum, they still contain a significant amount of unburned material due to the fact that it is impossible to send the primary combustion air into the mass of waste all along the drum.

In conventional ovens, these ash and chews rich in tTtatière = unburnt fall directly into the ashtray or into an Ott well. The temperature is insufficient to complete their destruction. We therefore obtain an unacceptable final unburned rate with regard to the environment and regulations.

 In a + or according to the invention, the rotary drum opens into a static final combustion chamber, the combustion surface of which consists of a horizontal flat hearth, provided with combustion air diffusers and comprising an auxiliary burner intended to maintain in all circumstances the temperature necessary for the perfect destruction of waste.

The combustion residues leaving the drum fall from a certain height, 500 mm or more, onto the floor, which has the effect of dislocating them and aerating them.

The primary combustion air, sent by side injectors and by diffusers embedded in the floor, can thus penetrate into the mass of waste and ensure its complete destruction.

 To further improve ventilation and therefore the perfect destruction of combustible waste, a tackling device opens out at the floor.

This device consists of several metal blocks ost other refractory material, of square or rectangular section, placed with a small clearance side by side and occupying the entire width of the sole.

 ; At rest these blocks remain outside the chamber, under the rotating drum.

Periodically, part of the blocks, for example the even blocks counted from the right, advance a certain distance and penetrate into the hearth by practically scraping the sole, then quickly return to their rest position.

Then, after a certain time, the other blocks, therefore odd, make the same movement.

These actions have the effect of gradually pushing the residues towards the ash removal opening and creating ventilation grooves.

R for periods longer than that of the old-fashioned nerling operations, it is necessary to produce more or less complete ashes of the sole
For this, the totality of the blocks, even and odd, is advanced at the same time over the desired distance and pushes back the ashes and bottom ash to the ash removal orifice.

For certain types of waste, it might be preferable to remove the rotary primary hearth or to replace it with a static primary hearth comprising means ensuring the progression of the residues, for example with blocks identical to those used in the final combustion chamber.

The invention will be described in more detail with reference to the accompanying drawings, by way of nonlimiting example, in which FIG. I represents an oven according to the invention seen in longitudinal section and FIG. II represents a detail of embodiment of the device. old-fashioned and repressed ash.

The oven consists of a rotary cylindrical primary hearth (1) slightly inclined, and a loading device (2) for the introduction of waste into the primary hearth.

An ignition burner (3) ignites the charge which then progresses by rotation of the hearth towards the final static combustion chamber (4) where it falls on the hearth (5).

A burner (6) and lateral air inlets (7) and under the hearth (8) maintain and activate the combustion of waste.

For certain wastes, the rotating primary hearth can be eliminated or replaced by a static primary hearth itself comprising one or more floors of hearths equipped with the device (11) for annealing and ash removal.

Periodically, the even (9) or odd (10) rows of tacking and ash removal blocks (11), @ enter into the chamber (4) to ventilate and repel the combustion materials towards the orifice (12) for evacuating ashes.

The fumes escape through the upper orifice (13) towards the post-combustion chamber.

Thanks to this design and to this process according to the invention, the destruction of waste, even relatively wet, takes place quickly and efficiently at high temperature with a minimum of additional energy consumption and without producing excess unburnts. .

The main application of the invention is economic destruction, without smoke and polluting odors and with a minimal rate of unburnt in ash and ash, common hospital, household and industrial waste.

Claims (2)

CLAIMS 1 - Oven for the incineration of household waste, hospital, industrial or other waste, comprising a loading device (2), a burner (3) and an after-combustion chamber (13), characterized in that it understands and uses in combination; a primary hearth of the rotating type (1), opening at a certain height above a hearth (5) in a final static combustion chamber (4), comprising an auxiliary burner (6) and air inlets primary (7) and (8) and equipped with a specific device (11) for annealing and for discharging the ashes towards the discharge orifice (12) in the ashtray.  2 - Oven for incineration, according to claim 1, characterized by the + that, for certain waste, the rotating primary hearth can be removed or replaced by a static primary hearth comprising itself a bare several floors of floors equipped with ringing and ash removal device (11).  - Oven for incineration, according to claims 1 or 2, characterized in that the device (11) for annealing and ash removal consists of several blocks of metal or other refractory material, of square or rectangular section, pairs (9) and odd (10) placed with a small play side by side, occupying the entire width of the sole (5) and can penetrate more or less, deep into the chamber by practically scraping the top of the sole (5)  4 - Oven for incineration, according to claim 3, characterized in that the even refractory blocks (9i and odd (10) can be actuated alternately or simultaneously