FR2694567A1 - Process for the management of solid and liquid waste in a solid bed pressure gasification process - Google Patents

Abstract

a) Process for the management of solid and liquid waste according to a process of gasification under pressure on a solid bed, b) Process characterized in that at the gasifier under pressure on a solid bed are fed 1 to 80% of waste and 20 to 99% of gasification material, in the form of lignite lignite, the coal portion being adjusted so that the calorific value of the gasification material is at least 12 MJ / kg, that the heavy metal parts of the waste having a boiling zone above 650degree C, related to the coal portion, are below 5 g / kg of coal, that the granulation of the gasification mixture below 10 mm is not greater at 20%, and that the portion of the waste components having a bulk density of less than 400 kg / m3 does not exceed 50% of the gasification material.

Description

i

  "Process for the management of solid and liquid waste

  according to a gasification process under pressure on solid bed "

  The invention relates to the field of gasification

  and in particular gasification under pressure on solid bed as well as the field of waste management.

  Solid bed gasification is carried out using the most diverse materials.

  such as raw lignite, briquettes of lignite, ligneous lignite and coal The quality of these materials used, with regard to the ash and water content, can fluctuate within wide limits. Preparation expense for the gasification material is low. This relatively high ease with which gasification under

  The pressure on the solid bed accommodates the gasification material, and the possibility of using the products as materials has resulted in another, also, baking waste.

  The fundamental disadvantage of solid bed pressure gasification is that of dust, high boiling and low boiling hydrocarbons, and water soluble inorganic and organic combinations, are

  contained in the raw gas and that

  Costly nexes are needed to extract and

  to collect the different products as well as to avoid

risks to the environment.

  By the document DD 259 875, there is known a proposal according to which, to avoid these products

  the height of the fuel spill.

  in the solid bed pressurized gasifier is extremely low and because of the temperatures thus obtained of about 1000 C in the gas chamber, tars, oils and dust particles contained in the raw gas are converted into gas raw in the gas chamber This process is not

  controllable from the point of view of the safety

  because of the extremely low discharge of the solid bed, it provokes the irruptions of oxygen which may result in gas explosions.

  in the connected facilities.

  There is further known a proposal according to DD-PS 43 253, in which the liquid and solid constituents contained in the gas, must be converted into gaz by auto-oxidation with addition of

  Gasification means This process is not legal.

  economically because some of the gas produced is burned A certain definite conversion

  liquid and solid constituents is not guaranteed.

  In addition, the proposal does not contain any additional safety measures and there is reason to fear that

  the process described, gas explosions.

  In the document DD 150 475, it is indicated a solution according to which by implementing a

  hydrogenation catalyst during a post-

  gasification of crude gasification gas under pressure

  On the solid bed, very high hydrocarbons must be converted by hydrocracking. This process has the disadvantage that the inlet temperature of the raw gas in the post-gasifier must be adjusted.

  on the operating temperature of the catalyst.

  This in the case of the implementation of lignite in the gasification process, can not be realized

  than with a complex technique of control and

  Another disadvantage of the process is the

  Fast catalyst lure by coal dust and ash particles that are driven by the raw gas and the resulting high operating costs. In DE-OS 253 219 7 and 253 219 8, it is furthermore stated that for the post-gasification of hydrocarbons

  from the crude gasification gas under pres-

  On a solid bed, this raw gas, with the addition of oxygen, is introduced into a post-gasifier which contains a solid bed of inert materials or catalytic materials, thanks to which, because of

  temperature rises, gasification reactions

  and cracking must occur.

  This method is disadvantageous in that, in

  this case, a control of the composition of the raw gas and

  if that of the amount of raw gas in the post-

  gasifier, is not possible, and the discharge of the solid bed into the post-gasifier can result,

  because of pollution as a result of the

  and ash, to a collapse in yield,

  or at the end of the gasification process.

  For waste containing harmful organic substances, such as dioxin and furan,

  as well as heavy metals, it is proposed that

  to treat residues containing

  heavy metals, by integration into

  gileux (DE 391 825 9, DE 371 348 2, DE 391 901 1 or

  DE 350 221 5) to obtain solid products

  These can be landfilled and can be partially deposited at a very high expense in underground dumps. Other solutions provide for mergers

  Such solutions are described in documents DE-

  393 934 4, DE 320 698 4 These installations require

  a very high energy expenditure They are

  currently mainly at the stage of

  laboratories and pilot plants and still need to be transferred to the

  practice, considerable time and considerable effort

development.

  In the gasification technique, document DD 267 880 discloses a proposal according to which a liquid fuel containing ash is brought with steam to the reaction chamber via a pipe.

  separately and independently of a burner

  their which is fed with a fuel in the form of dust, and the oxygen necessary for the partial autothermal oxidation of the liquid fuel containing ash, is brought to the gasification reactor

  through the coal dust burner

  good. The gasification of liquid residues requires, according to this process, a significant implementation of coal dust, the use of which results in

  high gas production costs The amount of

  liquid sidus implemented is very limited in the

case of this process.

  Other patents considered for this analysis in the field of solid bed pressure gasification, such as DE 261 930 2, DE

  334 238 3 and DE 332 720 3, which propose for the

  inorganic harmful substances, an extra-

  liquid slag, do not indicate

  to prevent heavy metal vapor absorption of the raw gas.

  The problem and the object of the invention

  ist to complete the processes for the management of

  solid and liquid waste so as to be able to obtain,

  with a high rate of return, an excellent elimination

  of inorganic harmful substances or

  organic harmful substances at the point of

high boiling.

  This object is achieved in accordance with the

  thanks to the fact that 1 to 80% of waste and

  at the same time 20 to 99% lignite in pieces, are

  brought into a gasifier under pressure on a so-

lide.

  The percentage of lignite fed is adequate

  percentage of harmful substances as well as

calorific value of the waste.

  This percentage is adjusted proportionally to the content of salts, heavy metals, dioxin and

  in furan, and is inversely proportional to the

  In the solid bed pressurized gasifier, by forming a defined temperature profile in the fuel explosion, the lignite is converted to a temperature of 300 to 800 ° C and for a residence time greater than 1 hour in an activator with a specific surface of about 400 m 2 / g, which together with the gasification gas from the waste, adsorbs the vapors of heavy metals, salts, dioxin and furan, and the

  transports to deeper areas of the

  with temperatures of about 1 2000 C A

  temperatures, combinations of organic substances

  harmful substances are destroyed and inorganic combinations are predominantly integrated

in the slag taking birth.

  The establishment of the aforementioned temperature profile, the maximum temperature in the expansion and the residence time of the lignite at temperatures of

  300 to 8000 C for the formation of the activator, is re-

  as follows in the case of a solid bed pressurized gasifier with a volume of about 80 m 3: the residence time of the lignite greater than 1 hour in a temperature range of 300 to 8000 C is

  obtained by setting an oxygen load of approxi-

  ron 3400 m 3 02 / h Lower oxygen loads

  lead to longer residence times.

  the maximum temperature in the expansion is re-

  by the choice of the steam-oxygen ratio For a vaporoxygen setting of 7 kg of steam / 1 m 3 i N. 2, the maximum temperature is about 1 2000 C. With the lowering of the vapor-oxygen ratio, the

  maximum temperature increases correspondingly

you.

  the position and conformation of the reaction zones

  the temperature profile of the zone temperature measurements at the periphery of the solid-bed gasifier in one or more planes are maintained at the required level by continuous extraction of the slag taking into account the

  ratio of the quantity of mineral substances in-

  produced at the quantity of slag extracted

  correct setting, the average value of the temperature

  at the tip of the rotating grid

  te, is about 3500 C and in the plane placed 2 m

  much higher, about 4500 C But the maximum temperature must be constantly in the vicinity of the ash melting temperature An analysis of the size of the extracted slag, confirms the optimum maximum temperature when granulation

  less than 5 mm does not exceed 40%.

  As other control parameters on the position and conformation of the reaction zones, it is possible to use the C 02 content of the gasification gas

  which must be less than 40% by volume, the temperature

  the output of the raw gas, which must have

  between 250 and 3500 C, the temperature of

  extracted between 250 and 350 ° C

  and the differential pressure of the proliferation of

  which should not rise above 10 k Pa.

  An optimal way of proceeding is

  to be obtained by an algorithmic combination

  of all the parameters listed.

  The solid waste feed in the solid bed pressurized gasifier is carried out in admixture with coal via an airlock. In the case of a compact form, the granulation

  should be between 5 and 100 mm, while the densi-

  of the total mixture must not be less than

re at 500 kg / m 3.

  Liquid waste with a content of

  from 1% to 40% are introduced to the

  superior and at a central gasification

  under pressure on a solid bed, with a fraction

  from 1 to 20% of gasification materials used

  directly in the profusion.

  As waste, can be treated

  shredded light products, waste material

  plastics, textile waste, automotive tire trimmings, paper and wood waste, charged active coke, contaminated soil, sludge and sludge, as well as mixtures of oil and tar containing

solids.

  The removal of slag out of the gasification

  under pressure on a solid bed, is carried out in

  tinu using a rotating rack, and through

  The slag does not contain any environmentally harmful substances. It can be used in the building materials industry.

  truction or be landfilled.

  The raw gas leaving the gasifier under

  pressure on solid bed is still responsible for

  harmful substances which, because of their low boiling point, are not transported

  the lower zones of expansion with a temperature

  erated to be destroyed or rendered harmless. They are treated in

  gas preparation and in con-

  gas densification and / or in

flow rate zeification.

  The advantage of the process according to the invention

  lies in the fact that vapors of sub-

  harmful stains are absorbed by the activator

  from coal in the solid bed pressurized gasifier and entrained in higher temperature zones where they can be made harmless, as well as in the production of the activator usable for the purpose mentioned above in the same reactor where also waste treatment. An exemplary embodiment of the invention is shown in the attached drawing and will be described

in more detail below.

  In a solid bed pressurized gasifier 1, which is operated under a pressure of 25 bars, about 10.5 tons of waste are introduced.

on time.

  The components of the waste are fixed in the table below: Heavy metals boiling point 6500 c mg / kg g / h heating value MJ / kg MJ / hx 103 granulation mm Mass flow% t / h Bulk density 400 kg / m 3 Density Mass flow kg / m 3 t / h (2) 3 t / h of contaminated soil (3) 2 t / h of products

light torn

quetés (4) 2 t / h of waste

contaminated wood

  mined (5) 0.5 t / h of tire trim (6) 2 t / h of decantation sludge (7) 1 t / h of creosote and solids mixture 1, 5 6.3 8.0

10500 28.0

4.0

25.1

4.5 12.6 16.0 14.0 8.0, 1

2.1

0.1

0.1

2 0.01

0.2

0.2

  , 5 t / h of waste 830 g / h, 2 x 103 MJ / h 2.71 t / h 0.5 4.5 t / h KO on o% The coal requirement is determined corresponding to the predefined limit values , such as the heavy metal content in relation to the coal portion of less than 5 g / kg, the heating value greater than 12 MJ / kg of gasification materials, the portion of grains of less than 10 mm less than 20% in the gasification material, and waste components with a bulk density of less than 400 kg / m 3 less than 50% or the total bulk density

  greater than 500 kg / m 3 in the gasification

  tion. In the exemplary embodiment indicated for a quantitative flow rate of heavy metals of 40 830 g / h, there is a coal requirement of 8.166 t / h (40 830 g / hr).

  heavy metals / h: 5 g of heavy metals / kg of lignin

  te) For this portion of coal, the other limit values (calorific value, granulation less than mm, and bulk density less than 400 kg / m 3) are all respected A modification of the components

  It is not necessary The quantity of

  zeification per hour, which is fed to the pressurized gasifier 1 on a solid bed, is therefore 10.5 t of

  waste 4 + 8,166 t of lignite 8 = 18,666 t The quantity

  the oxygen required for gasification is

  0.0083 m 3 at normal pressure 02 / MJ heat capacity

  This results in an amount of oxygen of: (80.2 x 103 MJ / h + 16.8 x 103 MJ / hx 8.166 t / h) x 0.0083 m 3 i N / MJ = 1800 m 3 i N / h

  The residence time for the activation of the

  The result of this adjustment is calculated as follows: • Apparent volume of the reactor • Portions between 300 and

5000 C

  Quantitative Flow of Gasification Material / Bulk Density of the Gasification Material m 3 x 0.7 = 2.1 h 18.666 kg / h / 700 kg / m 3

  with 2.1 h, the activation time is sufficient.

  The amount of oxygen is introduced in

  10 with 12.6 t of steam per hour above the rotating grate 9 in the solid bed gasifier The vapor-oxygen ratio thus adjusted of 7 kg of steam / m 3 N 02, ensures in the bed gasifier solid, in the oxidation zone, a temperature of 1 2000 C. This results in a slag aggregate 12, in which the heavy metals are melted, in a total amount of 4 t / h, which is continuously slurried by the intermediate of the rotating grid 9, taking into account the ratio of the quantity of mineral matter introduced to the quantity of slag extracted (ratio

  = 1.2: 1), and is fed to recovery means.

  By means of temperature measurements 11 at the periphery

  In the reactor, control is made of the zone levels which are predominant for the formation of the activator. In the bed pressurized gasifier

  solid, the hydrocarbons contained in the earth

  are distilled, cracked or gasified.

  consisting of old tires and light shredded products, are converted to 40 to 70%

  gaseous constituents and 20 to 50%

  res 3 to 12% will, depending on the composition,

  in the ash / slag fraction The constituent parts

  wastes are extracted in the form of a mixture of ash and slag via

of the rotating grid.

  Through the collector chamber

  13 g of raw gas 13, 12 600 m 3 at normal pressure of dry crude gas and 8 400 m 3 at normal pressure of steam per hour, at a temperature of about 450 ° C., are sent via the collecting pipe. of raw gas 14 in gas treatment plants, gas condensate plants, and / or in flotation rate gasification plants This raw gas has the following composition

C 02 33.5%

Co -15.0%

H 2 36.0%

CH 4 12.5%

N 2 09%

02 0.1%

C 1 C 4 2.0%

  In addition, this raw gas contains about 90 g of cyclic hydrocarbon and aliphatic / m 3 at normal pressure and 10 g of dust / m 3 at normal pressure,

  which contains about 20% of

ders.

LIST OF REFERENCES

  Solid bed pressurized gasifier contaminated soil light shredded products contaminated wood waste pneumatic trimmings sludge mix of creosote and solid products lignite rotating grate mixture of gasification agents slag aggregate raw gas collecting chamber raw gas gathering pipe

4

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Claims (10)

  1. Process for waste recovery   solid and liquid, according to a process of gasification   in the case of gasification under pressure on a solid bed, characterized in that 1 to 80% of waste and 20 to 99% of gasification materials are fed to the pressurized solid bed gasifier in the form of lignite into pieces, the portion of   coal is adjusted so that the calorific   that the gasification material is at least 12 MJ / kg, that the heavy metal constituents of waste having a boiling range above 6500 C, relative to the coal portion, are below 5 g / kg of coal, the granulation of the gasification mixture being less than 10 mm is not more than 20%, and the portion of the waste components having a bulk density   less than 400 kg / m 3 does not exceed 50% of the gasification.   The process according to claim 1, wherein   in that the liquid waste has a content   solids from 1 to 40% and are brought directly   solids gasifier in a proportion of 1 to 20% of the gasification material Implementation.   3. The process according to claim 1, wherein   in that solid waste is brought into   solid-state gasifier in a common form   pact in pieces with a larger grain size   less than 5 mm and less than 100 mm, mixed with the coal.   4. The process according to claim 1, wherein   in that it can be implemented simultaneously   in the pressurized gasifier on a solid bed   of different wastes whose mixing ratio depends on their load of harmful substances, their density and the their granulation.   5. Process according to any one of   Claims 1 to 4, characterized in that the conduct of the gasifier process under pressure on bed   solid is carried out in such a way that it results   the temperature profile as well as the   the residence time of the gasification material and the conformation of the zones in the solid bed pressurized gasifier, an activated carbon, which adsorbs harmful substances (preferably PCBs and / or dioxin as well as heavy metals and / or or saline vapors) which are transported to solid bed gasifier zones with temperatures above 12000 C where destruction occurs   organic harmful substances or an inte-   merging of inorganic harmful substances   in slag particles.   Process according to claim 5, characterized   in that the residence time required for the formation of the activator in the temperature zone   activation time, is set using the hourly quantity re oxygen delivered.   The process according to claim 5, wherein   in that the integration temperature per   harmful substances is regulated by means of the   vapor-oxygen ratio and is controlled through   of the grain structure of the slag.   Process according to any one of   5 to 7, characterized in that the position   and the conformation of the reaction zones are now   at the level required by continuous extraction   naked slag through the lathe   taking into account the ratio between the quantity of mineral matter introduced and the quantity of   slag extracted, and permanent control is   killed by several temperature measurements.   9. The method of claim 8, wherein   in that the temperature measurements are made evenly distributed in two   plans on the periphery of the reactor.   10. Process according to any one of   Claims 1 to 6, characterized in that a coupling of the method is possible with   gas and condensate treatment and / or with   flotation rate gasification plants.