JPS61111948A - Apparatus for manufacturing cement clinker with small alkalicontent - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing cement by a drying method and a semi-drying method, and an apparatus for producing cement clinker with a low alkali content, which is made of a raw material containing alkali and other harmful substances, and a fuel containing harmful substances. . The invention is particularly suitable for firing cement clinker using preheaters, rotary kilns, and coolers.

Raw materials for cement production 111 contain certain amounts of alkali compounds, chlorine compounds, and sulfur compounds depending on geological conditions. This also applies to the fuel required. These chemicals are vaporized during cement clinker WA production in the hot kiln area, especially the sintering area, and are carried along with the exhaust gas stream in the direction of the preslitter. In the colder regions of the Kirno system these chemical compounds condense and enter the sintering zone again with the material flow. In that case, as a result of internal circulation, alkaline compounds increase, and these alkaline compounds accumulate sticky dust in the preheater.
After 1 degree precipitation, the quality of the produced cement was 4 degrees.

As is well known, certain aggregates containing amorphous or soluble silicic acid contain 0.6 mass percent N of the cement used.
It is possible to process concrete into concrete only if atO and Qi are This is advantageous for certain zones of aggregates containing silicic acid in the form of silica, since the alkali content of the cement used is reduced to 0.6 mass percent NatO equivalent during cement production.

According to Technical Hydrogen, the alkaline content of cement kritka is ``
A decrease in ... can occur through the so-called bypass system. In that case, in the transition zone between the Y-heater and the rotary kiln, part of the exhaust gas (flue gas) or the entire amount of exhaust gas from the rotary kiln is removed from the installation, dedusted and returned to the installation again or blown into the atmosphere. Be interrupted by releasing. Dump the dust that accumulates.

The gas is removed from the kiln at a point where the alkaline compounds are as gaseous as possible and the dust concentration is low, and then it is strongly cooled with cold air. In that case, the problem is dust in the cooling system! The purpose is to prevent alkali compounds from condensing on the way to the cooling device in order to prevent adhesion or precipitation. After cooling, a wet IFI (condensation) of the bypass gas is usually carried out, and subsequent dedusting can be carried out in an electric gas purification system. The cooled bypass gas is then conveyed directly to the atmosphere or fed to the flue gas of the kiln unit after the preheater.

Regarding the above issues, please refer to the publication of the Federal Republic of Germany 2335
045, Publication No. 2613610, Federal Republic of Germany Patent No. 2708486C, Federal Republic of Germany J! , is described in Japanese Patent Publication No. 2742099 and Japanese Publication No. 2838692.

The equipment and equipment for the production of low-alkali cement kritkas known from the technical water mills are expensive in construction and equipment.

A further disadvantage of these known devices is that they are difficult to operate if the alkaline compounds are already condensed and deposited on the dust before the gas is drawn in. That's especially true
w, no or unsatisfactory treatment of hazardous exhaust gases such as NOx; heat losses amounting to 50% of total heat consumption;
This eliminates the use of secondary air for consumption outside the semenodo clinker calciner.

The object of the present invention is to develop an inexpensive device that can produce cement concrete with a low alkali content in a manner that is compatible with the environment. This device converts the accumulated by-products into a usable form, making the use of secondary air possible.

The object of this invention is to develop an apparatus for producing cement concrete with low alkali content.

This device removes harmful components from flue gas at temperatures of 750°C or higher.
Especially alkaline compounds, or S Oe, Hrs -N
Ox, C1 and dust are also removed.

This task is accomplished as follows. That is, in the zone from the preheater to the rotary kiln, a water discharge reactor with a pump operated with cleaning fluid, in particular water, is provided at the flue gas take-off location, and at the end opposite the flue gas take-off there is a water discharge reactor with a pump. A collection vessel is connected, which has a ball tap for supplying fresh water, a chemical supply device, and a pure gas discharge pipe. From this pure gas discharge pipe a pure gas pipe incorporating a supporting ventilation fan leads to the preheater flue gas pipe. The pure gas pipe has a pure gas outlet to the atmosphere behind the support ventilation fan.

The pure gas pipe and the preheater flue gas pipe combine to form a flue gas mixing pipe, which leads to the electronic filter via a flue gas ventilation fan.

The collecting vessel, which has a heat exchanger with feed and return pipes, can be equipped with a cooler and is downstream connected to a Surano separator together with a pump. Sludge removal can be accomplished by providing a separate water circuit with a Surano separator.

The collection vessel can also be constructed as a heat exchanger, for example by means of a double jacket construction.

This new device for producing low-alkali cement concrete works in such a way that the flue gas is withdrawn as a so-called bypass gas by means of the negative pressure created by the injection water reactor at the flue gas withdrawal location.

In that case, between the cleaning water and the removed flue gas, a convex,
A strong and complete heat and mass exchange takes place. 1) The cleaning water and gas are brought to temperature, the dust and water-soluble chemicals or gases are transferred to the water phase, and the Sot binds to the CaO in the dust. It will be done. Most of the alkali is soluble in water; the remaining portion is contained in the insoluble residue.

From the jet water reactor, the mixture of wash water and remaining moist flue gas is introduced directly into the collection vessel after heat and mass exchange. In this collection vessel, the mixture is separated by a difference in density, and one portion of the solid is precipitated.

Washing water coming from the collection container is sucked through a pump attached to the jet water reactor, circulated, and supplied to the collection container again via the jet water reactor.

Depending on the precipitation of the solid residue, the total amount of water fed into the water injection reactor is removed from the collection vessel via a sludge 1) separator, or sludge removal is carried out by a separate water circuit. A slazono separator is connected in the water circuit.

In addition to sludge, purified wash water comes out of the Surano separator. The wash water may be heated again depending on the location.

In order to regenerate the wash water, chemicals such as pH adjusters, foaming agents, and surfactants should be added to the circuit.

This device contains alkali! Is it possible to produce a cement concrete with a nano equivalent of 0.6 mass percent or less?

The resulting by-products can then be used again for cement production or, for example, as fertilizer. In order to utilize the secondary heat, a heat exchanger installed in the collection vessel or a collection device configured as a heat exchanger can be connected to a heating device, for example, by means of a power supply.

Example Please provide detailed information regarding the figures showing the two embodiments.

In the first example (semi-drying method shown in Figure 1), a-tally kiln 1
An injection water reactor 4 is arranged at the flue gas take-off position 3 between the preheater and the grate preheater 42 . This jet q/f water reactor 4
is passed through a collection vessel 5, which has a heat exchanger I4 for secondary energy 111 with a feed/return conduit 13, a float valve 15, and a four-product feeder I9. A cleaning water conduit 20 is connected to 5.
A pump 12 and a heat exchanger 17 are arranged in this conduit. Furthermore, a purification pipe 25 is connected to the collection container 5, and in the purification pipe there are installed a suranono separation (10, a pump 18, a heat exchanger 1).
The Usurano fractionator 10, which is installed in
It is equipped with In the injection water reactor 4, a negative pressure is created by the washing water pumped during circulation.

This causes the flue gas to be sucked out of the grate preheater 2 at the extraction point 3, and as a result of this suction process there is a sudden and intense heat exchange between the circulating pump water as cleaning water and the bypass gas.
An exchange of substances takes place. This water/flue gas mixture is introduced into a collection vessel 5 in which the mixture is separated on the basis of density differences and converted into liquid and gaseous phases. The humid and cooled bypass gas, which is far away from the environmental pollutants, exits the collection vessel via the purifying exhaust pipe 6 and is discharged to the atmosphere from the pure gas outlet 24 by the supporting ventilation fan 7 in the pure gas pipe 21. The Shinto gas mixture is then discharged into the flue gas ventilation fan 8 and the flue gas mixing pipe 23 for treatment.
It is introduced into the electronic filter 9 through the.

The wash water or a part thereof is taken out from the collection container and led out from the hydrocyclone 10, and after Surano separation, the purified wash water is heated by the wash water circulation and sent to the "L pump 1".
8 is guided through the heat exchanger 17 which is discharged into the collecting container 5. In order to keep the amount of water in the device constant, fresh water is supplied to the collection container 5 via the float valve I5. This water cutoff is used in advance for cooling W+6 of the liquid cyclone 10 to create a concentration difference in order to reduce the water-soluble gas component by 11jl-J°.

The separated sludge 11 is then treated centrally according to the embodiments described below.

According to the second embodiment (drying method in FIG. 2), the jet water reactor 4
is located at position 3 of the flue gas outlet 11 at the transition between the vertical preheater 2 and the rotary kill/l and is recessed.

The jet water reactor 4 is fireproof and passes through a collection vessel 5, which includes a heat exchanger 7 for the utilization of secondary air.
514, a sending/returning conduit 13, and a flow pipe F15. The cleaning water conduit 20 has a liquid cycle τ: /10.
A pump 12 is provided for sludge separation and for driving the jet water reactor 4.

A negative pressure is created in the jet water reactor 4 by the pumped wash water during circulation.

In this way, only a bypass gas number ratio is performed at the flue gas removal location 3. As a result, the gas and wash water are deeply mixed, and there is a strong and complete heat and mass exchange between the two media. The water-bypass mixture is then introduced into the collection vessel 5, in which the gaseous phase is separated from the liquid phase due to density differences. After this, it is purified and moistened.
The bypass gas, which has been cooled by 1j, escapes from the collection volume 45 via the pure gas discharge line 6, in which case the gas supply is carried out in the pure gas line 21 by means of a supporting ventilation fan 7. The purified and cooled bypass gas is used to treat the vertical preheater gas. For this purpose, the pure gas line 21 leads into a preheater flue gas line 22.

The gas mixture thus created is conveyed by a flue gas ventilation fan 8 in a flue gas mixture conduit 23 to an electronic filter 9, in this way the drying rotary kiln which has been applied in prior art water hammers. Expensive treatment of preheater exhaust gas can be omitted. In order to keep the water 1 in the device constant, fresh water is pumped into the collection container 5 via the float valve 15.
I: Provided.

The dust concentration in the bypass gas when producing cement using the dry method is higher than when producing cement using the semi-dry method.
A hydrocyclone 1o is arranged between the collection container 5 and the pop 12 and does not require cooling. This is because the extracted sludge 11 prevents the soluble components from increasing beyond saturation.

Particular advantages of the invention are the low alkali content Y1° of the cement clinker, the overall low investment in the construction and equipment technology of the various parts of the equipment, in particular the expensive processing equipment and additional bypass gas. This eliminates the need for a filter, reduces the space required to install the corresponding cement clinker firing equipment, completely removes SO3 from dust and bypass gas, and improves the working environment.

- The essence of the major advantages of this system is that it does not require the addition of short piping lines, and there are no operational failures compared to conventional equipment, such as the generation of dusty sludge that sticks to the unit. Effective operation of the device according to the invention is guaranteed.

What is beneficial to history is that by-products that meet the purpose are created, and this by-product p1. Things are l'f! It is possible to use secondary heat effectively.

[Brief explanation of drawings]

Figure 1 shows the cement clinker firing equipment used in the semi-drying method.
Figure 2 shows a cement clinker firing device used in the drying method. Reference numeral l in the figure: Rotary kiln, 2: Preheater, 3: Flue gas extraction position, 4: Injection water reactor, 5: Collection container, 6: Pure gas discharge pipe, 7...Support ventilation fan, 8
... Flue gas ventilation fan, 9... Electronic filter, lO.
...Sludge separator, 1! ...Sludge, 12.. Pump for operating the jet water reflector, 13.. 4 feed/return pipes,
14゜I7...Heat exchanger, 15...Float valve, 16
...Liquid cyclone cooling device! 8 - Pump for purification pipes, 19... Steam supply for the equipment 11, 20... Cleaning water conduit, 21... Pure gas piping, 22... Preheater flue gas pipe,
23... Flue gas mixture pipe, 24... Pure gas discharge 1.
, 25...purification pipe.

Claims (1)

[Claims] 1) A flue between the preheater (2) and the rotary kiln (1) in an apparatus for producing cement clinker with low alkali, which comprises a preheater, a rotary kiln, and a gas purification device. A device characterized in that a jet water reactor (4) is arranged at the gas extraction position (3). 2) A collection container (5) is connected to the end of the injection water reactor (4) opposite the flue gas extraction position (3), and this collection container is connected to a fresh water supply float valve (15), Device according to claim 1), comprising a drug supply device (19) and a pure gas discharge pipe (6). 3) Pure gas pipe (21) with built-in support ventilation fan (7) runs from pure gas discharge pipe (6) to preheater flue gas pipe (22)
The pure gas pipe (21) is connected to the supporting ventilation fan (7).
) has a pure gas outlet (24) leading to the atmosphere at the rear, and a flue gas ventilation fan (8) leading to an electronic filter (9) is installed in the pure gas conduit (23). Range 1)
The device described in. 4) Heat exchanger (14) with feed and return conduits (13)
2. The device according to claim 1, wherein a sludge separator (10) with a pump (18) is connected downstream to the collection vessel (5), which is associated with a sludge separator (10).