JPS63139975A - Gas stream dry distillation of hydrocarbon-containing solid - Google Patents

Abstract

PURPOSE:To carry out dry distillation inexpensively, and efficiently with excellent safety and controllability by a simple operation, by finely dividing shale into a powder having a particle size of a predetermined value or below and transferring the powder by allowing a single stream thereof to flow through various parts to thereby dry, preheat, dry-distill, cool and burning same. CONSTITUTION:Shale RS which has been finely divided into a powder having a particle size of 1mm or smaller is dried and preheated to 120-260 deg.C in a drying part A consisting of a gas stream-conveying drying pipe 1, a cyclone 2 and a suction fan 3. The powder is then transferred to a preheating part B consisting of a gas stream conveying preheating pipe 4, a cyclone 5 and an initial dry distillation gas pipe 6, heated to 400-450 deg.C and fed to the dry distillation device 7 of a mixing/dry distillation part C consisting of a dry distillation device 7, a waste combustion gas pipe 8 for supplying heat, an air introducing port 9 for diluent air and a cyclone 11, where dry distillation is carried out. Dry-distilled gas G and oil mist are taken out. Unburnt waste shale SS-u is burnt by blowing the dry-distilled gas G and air through the waste shale conveying preheating ascending gas stream pipe 12 of a combustion part D into a gas stream circulating combustion device 13. Burnt waste shale SS-b is cooled in each of gas stream cooling devices 14-1-3 through the extrusion fan 15 of a gas CG is used for the make up of heat and waste heat boiler 16.

Description

[Detailed Description of the Invention] PA (Prior Art) It has been a long time since oil shale and oil sands, which have enormous potential as fossil fuels to replace heavy oil and coal, whose remaining amounts have been determined, have attracted attention. Research and development efforts are being carried out competitively around the world, and practical application is steadily progressing. There are several processes that have reached commercial scale or are close to achieving commercial scale, and there are countless published process examples.

The problem is that oil sands and oil sands have extremely poor energy reserves compared to heavy oil and coal, and only a small amount of energy can be extracted by processing a large amount. , is destined to no longer keep up with the economic pace.

From this point of view, most of the processes already published have low economic efficiency, and even those that are currently being implemented have to be split into three parts, the carbon part and the oil part, and the oil part remains at a commercial pace. Although various efforts have been made to increase the carbon content, residual combustible content in the hydrocarbon carbonized gas and waste sierre cannot be avoided. Therefore, in order to increase the efficiency of the entire process, it is imperative that the process utilizes the gas and residual carbon to the maximum extent possible.

On the other hand, in processes such as temperature increase heat transfer, volatilization, carbonization, and carbon combustion, the representative diameter of shale and its distribution are the biggest factors, and the type and appropriate size must be determined by the shale.

Efforts have been made to make the particle size finer with the passage of time, in order to make it easier to process and shorten heat transfer and reaction times.

Scale-up is possible, automatic control is easy,
This is because efficiency has been increased as a result.

As a first consideration, it is easy to think that the equipment and expenses involved in pulverization are significant and account for a large part of the cost, but in most industries, the cost of pulverization itself is 10%, which is roughly equivalent to 10% of the total cost of semi-finished products and finished products. If granules are not particularly required, or in terms of product appearance, it is currently wiser to backfill fine particles near the original mine, or to dispose of waste shale containing residual carbon, rather than using troublesome utilization techniques. However, this process is beside the point, and economic efficiency cannot be ensured unless we put our utmost effort into it.

In the cement industry, raw materials are pulverized to an average diameter of 30 to 50 microns and a maximum diameter of about 300 microns using a combination of airflow beds and rotating beds. Grinding costs account for less than 10% of direct manufacturing costs. This size is the most appropriate size for heat transfer, calcination, and tarinka mineral formation reactions, as well as transportation, storage, and handling.

If it is made even finer, the heat transfer and reaction time will be shortened, but
With existing crushers, the cost of crushing increases rapidly, and there are also some problems with handling.

On the other hand, if the grinding is made even coarser, the grinding cost will be commensurately reduced, but the mineral formation reaction will be non-uniform, the required quality will not be ensured, or at least the residence time will have to be increased, and the equipment will be difficult to handle. It has the disadvantage of becoming dull.

(Problems to be Solved by the Invention) The appropriate size for oil siere is preferably lumpy for fixed beds, granular for moving beds, and several mm for rotating beds.

In a well-known process that is actually being put into practical use, - is required to be at most 3 kat, preferably 2 wn or less. That is, the time required for the particles to be entrained in the air flow, transported, dispersed, and transferred to heat increases with the particle size, so in order to complete the heat transfer and reaction, the air flow pipe becomes significantly longer with the particle size, making it impractical.

The present invention provides a carbonization method that maximizes the recovery of oil from fine raw ore oil shale and has excellent equipment efficiency.

(Working as a means to solve the problem) The present invention is for pulverizing raw ore to a size of k 1 mm or less. The powder shale is heated to a temperature as high as possible in the range of 120 to 250°C, air-dried, dehydrated, and preheated.
Airflow cooling breath from 00 to 250℃.

In the carbonization of the present invention, the raw material shale is heated to a temperature of 400° C. by instantaneous airflow swirling heat transfer using a part of the waste shale combustion gas, initial carbonization is carried out, and further carbonization is carried out in the carbonization vessel.

In order to keep the indirect heat transfer at ℃ forward bending and the forward bending carbonization temperature before 500℃ as constant as possible, in addition to the combustion gas '1:! ′＼ E2 It will be used for the waste aging boiler that will be installed. In addition, part of the 500°C pre-bent gas used for temperature increase and heat retention mentioned above is
It will be installed in the middle region of the boiler to utilize residual heat.

In the present invention, most of the temperature raising before carbonization is carried out in an air stream, so
The particle size shall be k 1 rran or less. Fortunately,
In general, oil shale is easy to crush and is as hard as limestone, and in the case of the above-mentioned cement, if the direct cost is 10%,
Considering the pulverized particle size, the cost is only 173 yen. For cement, a 10,000 t/d facility has been put into practical use, and although it has not been realized due to the concentration of demand, it is possible, and from now on, it will be easy to use compact and large capacity equipment for oil and shale. facilities are possible.

It varies widely depending on the production area, but if you look at famous products that are produced around the world and have development plans, most of them are carbon distilled.
It starts and ends between 0 and 600°C.

In order to maximize the oil fraction, approximately 450 to 550
It is desirable to keep it constant at the optimum temperature of °C.

The initial carbonization rate is determined depending on the properties of the oil/siel, but it is usually heated up to 400°C for a few seconds before heating up to the optimum carbonization temperature, the amount of heat required for carbonation, and the amount of temperature lowered due to heat loss. , indirectly supplying heat from the outside.

The waste Sierre combustion is also carried out using airflow heating and a cyclone combustor type airflow swirling combustor to achieve complete combustion at 800 to 1000°C. This temperature range is the easiest among high-temperature technologies, and even for the same enthalpy, a method with a smaller amount of heat carrier and a higher temperature has a so-called higher heat value and is of greater utility value. This will allow us to operate the boiler and partially cover the heating of the raw material and reheating.

Cooling is also performed in an air stream bed, making full use of the heat-exchanged solids and gases, and by using a single flow, the process and equipment can be simplified.

Referring to FIG. 1, A is a drying section consisting of an air flow conveying drying pipe 1, a cyclone 2, and a suction fan 3. Here, the granular material Sierre is dried and preheated to 120 to 260°C. 120°C is the minimum temperature for drying, and 250°C is due to the raw ore Sierre.Since compound water evaporates in the 200C front layer, a higher temperature is recommended as long as no volatilization of hydrocarbon gas is observed. Although this is convenient for subsequent processes, it also lowers boiler efficiency, so approximately 200°C is best.

The preheating section B consists of an airflow conveying preheating pipe 4, a cyclone, and a carbonized gas vibro containing a conveying combustion exhaust gas. The optimum temperature for initial carbonization is around 400°C depending on the properties of Nair, but after drying and calcination (dehydration)
The amount of gas is determined by the temperature of the raw material shale, which is made as high as possible in the range of 0 to 250° C., and the temperature of the combustion exhaust gas, and it is naturally preferable that the amount of gas be small. Within the range of gas amount determined by these temperature relationships, no matter how small the amount is, it is sufficient for airflow conveyance.

Carbonization starts before 400℃ in quasi-static change, but the temperature conductivity of metals and common minerals is 1710 to 17100.
Since the temperature is about 100%, it takes a long time for the center temperature to become equal to the surface temperature. In this airflow conveyance heat transfer, it is 1 second forward bending,
Particle size and particle size distribution play an important role here. When the average diameter is around 100 microns, it takes a few tenths of a second for the center temperature to reach the midpoint of the difference from the surface temperature.

This is because the gas is closely connected to the optimum temperature of the above-mentioned initial carbonization, and the process efficiency of the post-treatment is reduced. However, if there is no such concern or there are operational stability issues that outweigh this concern, it is possible to increase the initial dry distillation fraction due to this air flow.

Furthermore, if the carbonization characteristics of Nair are carried out suddenly from, for example, 450°C and efficiently terminated at 550°C, then when the temperature is raised to 400°C, the used gas is not the initial carbonized gas vibro, In some cases, it may also be used to reheat the steamer. The choice of this system will depend on the nature of the raw Sière, such as keeping the initial carbonization to a small amount as much as possible by not allowing carbonization to take place anywhere, or by increasing the amount considerably and making the carbonization vessel smaller instead. There used to be.

The mixing/carbonization section C includes a carbonization device 7, a combustion exhaust gas pipe 8 for heat replenishment, an air inlet 9 for dilution, and a carbonization gas 1.
It consists of a second dust removal cyclone 11.

The raw material Sierre heated to 400 to 450°C as mentioned above enters the carbonization vessel 7, and after being replenished with ripening, the optimum temperature for carbonization is usually 50°C.
The temperature is lowered to 0°C, the heat required for carbonization is replenished, and the heat loss of the equipment is also compensated. This allows the complete carbonization to be carried out optimally.

This heat supply is indirect heat exchange and is used for drying or plaster calcining. steam tube rotary heat exchanger,
A pan mixer with a vibrating conveyor type stirrer, a tank with a ribbon spiral for mixing, a double drum mill, etc., depending on the characteristics of the raw material Siehl and its carbonization process, and also considering the size, economy, safety, and stability of the unit. equipment for optimal mixing, heat transfer, and carbonization gas and oil extraction. Consider ways to improve indirect heat transfer efficiency, such as by inserting a pipe, using a jacket type, or using a fin type.

The combustion section consists of a waste ale conveying preconditioning updraft pipe 12 and an airflow swirling type combustor 13, which applies hydrocarbon-based gas combustion of carbonized gas for the core frame, introduces make-up air, and produces exhaust gas as a result of combustion. Mainly in the boiler, some of the raw material Sierre is used for preheating and carbonization, and then used again in the boiler, combustion waste Sierre is discharged, and its enthalpy is used to preheat the combustion air. In terms of quantity, the above-mentioned combustion make-up air may also be used for cooling, that is, for the combustion waste air conveying heat transfer.

The cooling section E includes a multistage cyclone 14, an air flow conveying pipe, and a forced fan 15. Cyclones are classified as 3 due to temperature.
The steps are appropriate. If there are 4 stages, the cooling temperature of the waste sierre will be lower, and the heat recovery from the air will be even greater, but the equipment will be larger, so it is determined by taking into account these factors.

leading to. The system as a whole is extremely simple, with solid flow and
Both airflow penetrates the system within 1 minute. The sierre stagnates in the carbonizer 7, but since it is a fine powder and has good carbonization properties, 2 to 3 minutes is sufficient.

Figure 2 schematically represents the above process, mainly consisting of solid (air) and gas (air/gas) flows, with the vertical axis representing temperature and the horizontal axis representing processes unrelated to time. Separate division, solid line is siere, band shape is gas, arrow is flow direction, ■
The marks indicate mutual heat transfer. The numbers in 0 indicate the proportional amount when the unit amount of raw material air is 1, and the numbers in parentheses indicate the corresponding amount of air/gas.

For example, if the solid is 2g, the value of the gas is equivalent to -N. Additionally, the temperature range and unit amount of gas used in the waste heat boiler are shown on the left.

Of course, all numbers are just examples.

Figure 3 shows the heat balance estimated for a practical machine based on the results of the Process Development Unit (PDU).

Although attempts are made to recover as much oil as possible and to avoid the heat required for carbonization, equipment damage, and sensible heat of carbonization gas and oil mist, the process is done at a low temperature, but residual carbon increases. Complete combustion increases the sensible heat of combustion exhaust gas +S+ At the same time, the sensible heat of combustion of waste Sierre is recovered as much as possible by the multi-stage airflow maturation recovery device. However, the sensible heat of the cooled waste ale,
Since it is impossible to avoid the dissipation heat loss of the combustor, the decomposition heat of carbonates, and the sensible heat after further heat recovery of the boiler exhaust gas, the amount of heat that contributes to steam generation is the remaining heat from oil extraction, that is, the carbonization gas. It is difficult to imagine that the amount of heat held by hydrocarbons and waste sierre would be reduced to the level of powder.

However, all existing processes are efficient and economical systems.

(Effects of the Invention) The present invention is based on the pulverization of raw ore Sierre, and necessitates the use of a heat recovery device such as a steam boiler.

Existing processes do not assume pulverization, and some mention the installation of a waste heat boiler, but an example of proactively utilizing surplus total heat ff1t is a good large-capacity one. There is no problem in its existence. The entire heat content of the raw ore sier is extracted, and there is nothing to dispose of, and the cooled waste sier is powder, so it is easy to handle and has good soil destruction properties when backfilled.

The carbonized gaseous hydrocarbons are utilized for combustion, but may also be used for other purposes in some cases, and the waste sierre-containing hydrocarbons and carbon are completely combusted. The entire process is extremely simple, equipment efficient, and has almost no limits on scale-up. It is easy to control automatically, easy to operate, and has excellent stability. It can be said that any existing process is simple and economical.

[Brief explanation of the drawing]

FIG. 1 is a schematic flowchart of the present invention, FIG. 2 is a characteristic diagram showing temperature and flow, and FIG. 3 is a diagram of the heat balance of the present invention. 1: Air flow conveyance drying pipe 2: Air flow conveyance drying knife 5 = Exhaust gas fan 4: Air flow conveyance preheating pipe 5: Air flow conveyance preheating cyclone 6: Initial carbonization gas pipe 7: Carbonization vessel 8: Carbonization group temperature raising/heat retention pipe 9: Carbonization Air inlet for group heating and heat retention 13: Swirl type combustor 14: Combustion waste siere 15: Cooling fan Air flow cooling device 16: Waste heat boiler Applicant: Director of the Agency of Industrial Science and Technology Sachi Iizuka Mihane 3 Figure F (, -! 1ia

Claims (1)

[Claims] Shale crushed to 1 mm or less is pushed through the entire system.
A single airflow by a suction fan flows through the airflow, and the airflow conveys and
An air-flow carbonization method for hydrocarbon-containing solids that utilizes swirling to perform transfer, drying, heat transfer, partial carbonization, combustion, and cooling.