TWI700259B - Waste incineration fly ash resources reproduction-based light-weight pellet material, preparation method and manufacturing system thereof - Google Patents

Abstract

The method for manufacturing a waste incineration fly ash resources reproduction -based light-weight pellet material of the invention comprises mixing a raw material consisting of a waste incineration fly ash, an additive containing a silicon aluminate and the like in uniform processing, and then adding water to be granulated into a green pellet ball in half-dry state, and further fired it into a light-weight pellet material through a thermal processing in a rotary kiln. Because of utilizing the rotary kiln apparatus system and molten sintering curing process in the present invention, the toxic substance such as heavy metal, dioxin and furan of the waste incineration fly ash is able to be decomposed and then stabilized in the glass-solidified product formed by melt sintering. Further, through air bubble formed form vaporization of the additive containing a silicon aluminate, the waste incineration fly ash is made to form a light-weight pellet material, which has pores in entire inner and is able to be used in construction engineering projects.

Description

Waste incineration fly ash resources to reproduce lightweight material, and its production method and manufacturing system

The present invention relates to a waste incineration fly ash resource recycled lightweight material, its production method and manufacturing system, and the method for manufacturing lightweight material of the present invention, especially the production of a waste incineration fly ash resource recycled lightweight material The method can effectively stabilize the waste incineration fly ash, and can prepare light pellets with high economic value.

The secondary products produced by the incineration of garbage by garbage incinerators are collectively referred to as municipal solid waste incinerators. Depending on the location and nature of their output, they can be divided into three types: bottom ash, fly ash, and reacted ash. Among them, fly ash and reaction ash are commonly referred to as collectively. Waste incineration fly ash (incineration fly ash). According to the different properties and contents of various incineration ash residues, each has its own treatment method. According to the domestic treatment status, bottom ash is a "general industrial waste" specified by the Environmental Protection Agency, which is a material that can be directly reused. The waste incineration fly ash (referring to fly ash, reaction ash, or a mixture of fly ash and reaction ash) is "hazardous industrial waste" because it contains high concentrations of toxic substances such as heavy metals, dioxin, and furans, resulting in waste Incineration fly ash cannot be reused directly, but needs to be stabilized, and after the stabilized treatment, it must pass the toxicity characteristic leaching procedure (hereinafter referred to as TCLP) dissolution standards before it can be buried or recycled.

For the stabilization treatment of waste incineration fly ash, the currently commonly used method in China is the cement curing method, which is uniformly mixed with an appropriate amount of cement and waste incineration fly ash, and the cement curing treatment equipment is used to shape it and fully apply it Health preservation, so that the heavy metals in the waste incineration fly ash reach a chemically stable state. The stable mechanism of the cement curing method is to use the strong alkalinity of cement (pH=12), which can oxidize water-soluble heavy metals into insoluble compounds.

However, although the cement curing method is simple to operate and has become a common way to dispose of waste incineration fly ash, it still cannot achieve complete stability after curing. There are still doubts about the elution of heavy metals for a long time. The waste after cement curing Incineration of fly ash has no subsequent reuse value. It can only be covered with soil for burying. In addition, there is a problem of volume increase after solidification, which increases the subsequent handling and burying costs. Take the current woodland waste incineration fly ash cement curing plant in Taipei County as an example. It can process 63 tons of waste incineration fly ash per day. After adding curing agents, chemical stabilizers, cement and water, it will eventually produce 92 tons of waste incineration. The volume of the fly ash cured product is about 1.5 times larger.

In the contents of waste incineration fly ash, the main harmful substances are solid heavy metals (in the form of chlorides, oxides, sulfates, and silicates), as well as gaseous dioxins (PCDDs) and furans (PCDFs). It has a very high leaching rate and toxicity. However, since the commonly used cement solidification method cannot effectively stabilize the waste incineration fly ash for a long period of time, based on the current foreign practice and research results, it is believed that sintering solidification and melting solidification are better. The two processing methods are briefly introduced below.

The sintering and solidification method is to mix the waste incineration fly ash to be processed with the material with aluminosilicate composition, and then after granulation molding, it is fired into a vitreous solid at a high temperature of 1000~1100℃. It is stable The mechanism is to stabilize and seal heavy metal components through the dense crystalline structure of the glass body. In addition, the maximum capacity reduction rate can be over 1/2.

In addition, the melting and solidification method promotes thermal decomposition, combustion and gasification of organic matter in waste incineration fly ash at high temperatures (above 1300°C), while inorganic matter is melted to form a glassy solid. After melting and solidification, the organic pollutants such as dioxin and furan in the waste incineration fly ash are decomposed and destroyed by heat, and the heavy metal salts with lower boiling points, except for a small part of the decomposition due to gasification, most of them are transferred to the vitreous In the cured product, the possibility of leaching can be greatly reduced. After the waste incineration fly ash is melted and solidified, the maximum volume reduction rate can reach more than 1/2.

In summary, the incineration fly ash generated during the waste incineration process must be stabilized. In addition, the cement curing method commonly used in China cannot effectively stabilize the above-mentioned toxic substances, but also has certain limitations in the reuse of the cured product after treatment. Compared with the cement solidification method, the sintering solidification method and the melting solidification method can decompose and stabilize most of the toxic substances in the waste incineration fly ash. Therefore, the waste incineration fly ash treated by these two methods can be buried. And there is no concern about the dissolution of toxic substances. However, the waste incineration fly ash after treatment has no economic value after being buried, and the manual treatment and land cost required for the burial are also quite high. Therefore, how to make the treated waste incineration fly ash into a lightweight building usable Pellets have become the goal of the industry and research units.

In view of the fact that the existing method of burying waste incineration fly ash after treatment is quite uneconomical, the purpose of the present invention is to provide a method for making lightweight material from waste incineration fly ash resources, which combines sintering solidification and melting solidification. This mechanism can be used to make waste incineration fly ash into a lightweight material with high economic value.

In order to achieve the above objectives, the manufacturing method of the waste incineration fly ash resource remade lightweight material of the present invention includes the following steps: master batch preparation step: the dried waste incineration fly ash powder and additives are put into a mixing unit Add water and mix to form a masterbatch mixture with a moisture content in the range of 15%~35%; granulation step: put the masterbatch mixture into a granulation unit to make raw material with a particle size distribution of 2~20mm Ball; and firing step: the first raw material ball is transported to the firing unit for firing in a low-temperature stage and firing in a high-temperature stage in order to obtain light pellets. The particle density of the recycled lightweight material from waste incineration fly ash resources is in the range of 0.3 g/cm ³ to 1.8 g/cm ³ .

In addition, according to the technical idea of the present invention, there are no particular restrictions on what can be used as an additive, as long as it has fluxing, foaming and viscosity-increasing effects. For example, aluminosilicate-containing substances can be used.

In addition, according to one of the technical ideas of the present invention, substances suitable for use as additives further include aluminosilicates, aluminosilicate-containing crystals, aluminosilicate precursors, alkali metal oxides, and sources thereof Raw materials, for example, reservoir sludge, water purification sludge, stone processing sludge, clay, fly ash, furnace stone powder, river silt, kaolin, granite powder, brick powder, marble powder or a combination of them. For example, the additives are preferably reservoir silt, harbor silt, stone processing sludge, clay and other materials.

According to an embodiment of the present invention, the weight ratio of the waste incineration fly ash to the additive is in the range of 5 wt%: 95 wt% to 25 wt%: 75 wt%, and the waste incineration fly ash and the additive They are powders with a median particle size D ₅₀ ≦7 microns (μm). In addition, the weight ratio of the waste fly ash to the additive is not particularly limited. For example, it is preferably in the range of 5 wt%: 95 wt% to 25 wt%: 75 wt%; more preferably, it is 5 wt%: 95 wt%~25.5 wt%: 74.5 wt%; the best one is in the range of 5 wt%: 95 wt%~26 wt%: 74 wt%.

According to an embodiment of the present invention, the conditions for the low-temperature stage firing are: in a first predetermined time interval (t1), the temperature is increased from the first temperature (T1) to the second temperature (T2), and the rotation speed is 2 The range of ~6rpm; the firing conditions of this high-temperature stage are: in the second predetermined time interval (t1), the temperature is raised from the third temperature (T3) to the fourth temperature (T4). In addition, according to an embodiment of the present invention, firing in the low temperature stage further includes maintaining Y at a second temperature (T2) for X minutes; and, firing in the high temperature stage further includes maintaining Y at a fourth temperature (T4). minute. Furthermore, X, and Y are not particularly limited, and the two may be the same or different; for example, X, and Y may be in the range of 5 to 30, preferably 5 to 28 More preferably, it is in the range of 5 to 25, and the best is in the range of 5 to 22. Furthermore, t1, t2, T1, T2, T3, and T4 respectively conform to the following relations:

15 min≦t1≦60 min, 25 min≦t2≦50 min, and 0.6≦t1/t2≦2.4;

40℃≦T1≦700℃, 40℃≦T2≦700℃, and T1≦T2;

600℃≦T3≦1250℃, 600℃≦T4≦1250℃, and T3≦T4.

According to an embodiment of the present invention, the first predetermined time interval (t1) and the second predetermined time interval (t2) may be the same or different, and are not particularly limited. For example, for example, the lower limit of t1 is preferably 15 min or more, more preferably 16 min or more, and the best is 17 min or more; on the other hand, the lower limit of t2 is preferably 25 min or more, and more The best is greater than or equal to 26 min, and the best is greater than or equal to 27 min.

Secondly, according to an embodiment of the present invention, the upper limit of the first predetermined time interval (t1) is preferably less than or equal to 60 min, more preferably less than or equal to 59 min, and most preferably less than or equal to 58 min; on the other hand, The upper limit of the second predetermined time interval (t2) is preferably less than or equal to 50 min, more preferably less than or equal to 49 min, and most preferably less than or equal to 48 min.

Furthermore, according to an embodiment of the present invention, the first predetermined time interval (t1) and the second predetermined time interval (t2) are not particularly limited. For example, for example, the first predetermined time interval (t1) and the second predetermined time interval (t2) should satisfy the relational expression of 0.6≦t1/t2≦2.4, and preferably satisfy the relationship of 0.6≦t1/t2≦2.35 The relational expression is better to satisfy the relational expression of 0.6≦t1/t2≦2.30, and the best one is to satisfy the relational expression of 0.6≦t1/t2≦2.25.

According to an embodiment of the present invention, the first temperature (T1) and the second temperature (T2) of the low-temperature stage are not particularly limited, and the two may be the same or different. For example, for example, the first temperature (T1) is preferably in the range of 40°C to 700°C, preferably in the range of 40°C to 690°C, more preferably in the range of 40°C to 680°C, most Preferably, it is in the range of 40°C to 670°C. On the other hand, the second temperature (T2) is preferably in the range of 40°C to 700°C, preferably in the range of 40°C to 690°C, more preferably in the range of 40°C to 680°C, and most preferably It is in the range of 40°C to 670°C. In addition, the temperature difference between the first temperature (T1) and the second temperature (T2) is not particularly limited. For example, for example, the value of (T2-T1) may be above 50°C, preferably 100 ℃, more preferably above 150℃, and most preferably above 200℃.

According to an embodiment of the present invention, the third temperature (T3) and the fourth temperature (T4) of the high temperature stage are not particularly limited, and the two may be the same or different. For example, for example, the third temperature (T3) is preferably in the range of 600°C to 1250°C, preferably in the range of 600°C to 1240°C, more preferably in the range of 600°C to 1230°C, most preferably Those are in the range of 600°C to 1220°C. On the other hand, the fourth temperature (T4) is preferably in the range of 600°C to 1250°C, preferably in the range of 600°C to 1240°C, more preferably in the range of 600°C to 1230°C, and most preferably In the range of 600°C to 1220°C. In addition, the temperature difference between the third temperature (T3) and the fourth temperature (T4) is not particularly limited. For example, for example, the value of (T4-T3) can be above 50°C, preferably 100°C. ℃, more preferably above 150℃, and most preferably above 200℃.

According to an embodiment of the present invention, the waste incineration fly ash is fly ash, and the non-aqueous part of the masterbatch mixture contains the following components: silicon dioxide 49~58wt%, aluminum oxide 21~23 wt%, ferric oxide 6~7 wt%, calcium oxide 5~11 wt%, magnesium oxide 2~3 wt%, sodium oxide less than 1 wt%, potassium oxide less than 1 wt%, organic matter 1~5 wt%, the above ratio is the weight percentage of each component in the non-water part of the mixture.

According to an embodiment of the present invention, the waste incineration fly ash is reacted ash, and the non-aqueous part of the masterbatch mixture contains the following components: silica 44~56 wt%, trioxide Aluminum 17~22 wt%, ferric oxide 5~7 wt%, calcium oxide 6~15 wt%, magnesium oxide 1~2 wt%, sodium oxide less than 1 wt%, potassium oxide less than 1.5 wt%, organic matter 1 ~5 wt%, the above ratio is the weight percentage of each component to the non-water part of the mixture.

According to an embodiment of the present invention, the waste incineration fly ash is composed of fly ash and reaction ash, and the non-aqueous part of the masterbatch mixture contains the following components: silica 45~56wt%, two Aluminum 18~22 wt%, ferric oxide 6~7 wt%, calcium oxide 6~14 wt%, magnesium oxide 1~2 wt%, sodium oxide less than 1 wt%, potassium oxide less than 1.5 wt%, organic matter 1~ 5 wt%, the above ratio is the weight percentage of each component in the non-water part of the mixture.

According to an embodiment of the present invention, the additive contains at least aluminosilicate, preferably any one selected from reservoir sludge, water purification sludge, stone processing sludge, clay, and mixtures thereof.

According to an embodiment of the present invention, the lightweight material is a material used in general construction projects or gardening plants.

According to an embodiment of the present invention, after the firing step, a cooling step is further included: the light pellets obtained by firing are cooled and annealed.

According to an embodiment of the present invention, preferably, the dust recovered in the firing step is mixed with the ground fly ash, reaction ash and additives in the master batch preparation step.

In addition, the present invention can provide a system for manufacturing light-weight particles of waste incineration fly ash, which at least includes: a grinding unit for grinding waste incineration fly ash and additives into powder; a mixing unit that uses The waste incineration fly ash, the additive and water are mixed to form a master batch mixture; a granulation unit is arranged at the downstream end of the mixing unit to receive the master batch mixture from the mixing unit and produce The pellets are formed into raw pellets; and a firing unit, which at least includes a double-tube rotary kiln and a monitoring device; wherein the double-tube rotary kiln is formed by a drying and preheating kiln and a roasting kiln connected in series , And the drying and preheating kiln and the roasting kiln are each independently provided with a temperature adjustment mechanism and a rotation speed adjustment mechanism; the inlet of the drying and preheating kiln is arranged at the downstream end of the granulation unit for receiving The raw meal balls of the pellet unit are fired in the first stage; the roasting kiln receives the raw meal pellets from the drying and preheating kiln and is fired in the second stage at a temperature between 1100 and 1400°C to obtain light particles The monitoring device is electrically connected with the temperature adjustment mechanisms and the rotational speed adjustment mechanisms to detect and control the drying and preheating kiln, and the temperature and rotational speed in the roasting kiln.

The specific effects that the present invention can achieve include:

1. In the present invention, the aluminosilicate additive is added to the waste incineration fly ash, and then the light pellets are burned in a rotary kiln through a heat treatment process. The aluminosilicate additive is used to generate foaming gas at high temperature, and the The waste incineration fly ash is made into a light-weight material with pores throughout the interior, which can be used in construction projects, which greatly increases the economic value of the waste incineration fly ash after treatment, and eliminates the high labor and land costs of burying the waste incineration fly ash .

2. The invention uses rotary kiln system equipment to melt and sinter and solidify the heavy metals, dioxin, furan and other toxic substances in the waste incineration fly ash, decompose and stabilize in the vitreous solidified substance formed by melting and sintering, so it can effectively stabilize To reduce the toxic substances in the fly ash from waste incineration, the light pellets produced will not have any doubts about the dissolution of toxic substances, and can be safely used in construction projects.

In the following, different specific embodiments are listed and explained in more detail for the implementation of the present invention, so as to make the spirit and content of the present invention more complete and easy to understand; however, those with ordinary knowledge in this art should understand Of course, the present invention is not limited to these examples, and other same or equal functions and sequence of steps can also be used to achieve the present invention.

In this article, the scientific and technical terms used here have the same meanings as understood and used by those with ordinary knowledge in the technical field of the present invention. In addition, without conflict with context, the singular nouns used in this specification cover the plural nouns; and the plural nouns also cover the singular nouns.

In this article, the values and parameters used to define the scope of the present invention inevitably contain standard deviations due to individual test methods, so they are mostly expressed as approximate quantitative values. However, in specific embodiments, Relevant values presented as accurately as possible. In this article, "about" usually depends on the considerations of those with ordinary knowledge in the technical field of the present invention, and generally means that the actual value falls within the acceptable standard error of the average value. For example, the actual value is a Within ±10%, ±5%, ±1%, or ±0.5% of a specific value or range.

In the embodiment of the present invention, waste incineration fly ash and aluminosilicate-containing additives are provided as raw materials. The waste incineration fly ash can be fly ash or reacted ash. The aluminosilicate-containing additive has the effects of fluxing, foaming and viscosity increasing, such as reservoir silt, harbor silt, Stone processing sludge, clay and other materials;

Next, please refer to Fig. 1, which shows the standard step flow of the manufacturing method of the waste incineration fly ash resource reprocessing lightweight material of the present invention. The manufacturing method includes:

Masterbatch preparation step S1: Put the dried waste incineration fly ash powder and additives into a mixing unit, then add water and mix to form a masterbatch mixture with a moisture content in the range of 15% to 35%.

Granulation step S2: Put the master batch mixture into a granulation unit to form raw pellets with a particle size distribution of 2-20 mm.

The firing step S3: transport the first raw material ball to the firing unit to sequentially perform low-temperature stage firing and high-temperature stage firing, thereby obtaining light pellets.

According to another embodiment of the present invention, before the masterbatch preparation step S1, it may further include a raw material pretreatment step S4: firstly the garbage is incinerated into fly ash and additives (herein mainly reservoir sludge). Drying to constant weight, preferably, the waste incineration fly ash and additives are transported by scrapers to an oven for drying, and the oven temperature is between 95°C and 105°C. Then, the dried waste incineration fly ash and additives are respectively broken into pieces; preferably, this crushing step is broken into pieces using a jaw crusher. The crushed waste incineration fly ash and additives are respectively finely ground into powder and stored in their respective storage bins; preferably, this grinding step is finely ground by a ball mill to a median particle size D ₅₀ ≦ 7 microns ( μm) powder

Through the above raw material pretreatment step S4 of homogenization treatment such as drying, crushing and grinding, the raw material is manufactured into a homogeneous powder, which can be uniformly mixed in the subsequent preparation step S1 of the master batch mixture to Ensure that lightweight pellets with stable quality and excellent performance can be produced;

In the master batch preparation step S1, the ground waste incineration fly ash and additives are measured in an appropriate ratio, and then mixed with water to form a mixture with a moisture content of 15% to 35%, so that the mixture is The non-aqueous part (that is, the mixed solid of waste incineration fly ash and additives) can have a specific and better chemical composition. The mixture can have three formula designs. The first group is the fly ash series, which is only used for grinding Then fly ash and additives are mixed with water to form a mixture; the second group is the reaction ash series, which is only the reaction ash after grinding and the additives are mixed with water to form a mixture; the third group is the mixed ash series, which are respectively Take the ground fly ash, reaction ash and additives and mix with water to form the first mixture. In addition, the dust recovered in the subsequent high-temperature firing process can be added; the above three formula design principles are based on the used fly ash, The chemical components contained in the reaction ash and additives are adjusted in an appropriate ratio to the composition ratio of the chemical components required by each formula, as shown in Table 1:

Table 1 formula Fly Ash Series Reaction Ash Series Mixed series Use raw materials Fly ash + additives Reaction ash + additives Fly ash + reaction ash + additives + recovered dust Chemical composition (wt.%) Silicon dioxide (SiO ₂ ) 49~58 44~56 45~56 Aluminum oxide (Al ₂ O ₃ ) 21~23 17~22 18~22 Iron trioxide (Fe ₂ O ₃ ) 6~7 5~7 6~7 Calcium Oxide (CaO) 5~11 6~15 6~14 Magnesium Oxide (MgO) 2~3 1~2 1~2 Sodium oxide (Na ₂ O) ＜1 ＜1 ＜1 Potassium Oxide (K ₂ O) ＜1 ＜1.5 ＜1.5 Organic matter 1~5 1~5 1~5

The process of mixing ingredients can be based on the formula shown in Table 1. The ingredients can be measured with the electronic scale attached to the conveyor belt, and then mixed with water through a double-shaft mixer to homogeneity, ready for granulation.

Next, in the granulation step S2, the mixture is made into spherical raw material balls with a continuous gradation of 5-20 mm; preferably, the mixture after the mixing is completed is transported to The disc granulator is used for granulation, and the granulation method adopts the wet pelletizing method to avoid dust flying and implement clean production that emphasizes environmental protection;

In the firing step S3, the raw material balls are transported to the rotary kiln to be fired into light pellets. The highest furnace temperature used for firing is between 1100 and 1400°C, which can vary according to different recipes. And firing according to the preset firing curve. The firing unit can be a rotary kiln, and the exhaust gas of the rotary kiln must be desulfurized and collected by air pollution prevention equipment, so that it can meet the national air pollution prevention standards. The recovered dust can also be reused in the production of lightweight materials and mixed with waste incineration fly ash and additives in the mixing step to achieve the "zero waste" concept promoted by the Environmental Protection Agency.

According to the technical idea of the present invention, the raw material ball is fired in a low temperature stage and a high temperature stage in sequence; the conditions of the low temperature stage firing are: in the first predetermined time interval (t1), the temperature is changed from the first The temperature (T1) is raised to the second temperature (T2), and the rotation speed is in the range of 2-6 rpm; the conditions for firing in this high-temperature stage are: in the second predetermined time interval (t2), the temperature is increased from the third temperature (T3) ) Raise the temperature to the fourth temperature (T4); and t1, t2, T1, T2, T3, and T4 meet the following relations respectively: 15 min≦t1≦60 min, 25 min≦t2≦50 min, and 0.6≦t1/t2≦2.4; 40℃≦T1≦700℃, 40℃≦T2≦700℃, and T1≦T2; 600℃≦T3≦1250℃, 600℃≦T4≦1250℃, and T3≦T4.

In addition, in another embodiment of the present invention, after the firing step S3, a cooling step S5 is further included: the light weight material obtained by firing is cooled and annealed; preferably, the light weight material is Use a cooler to cool and anneal according to the pre-set slow cooling curve. In addition, after the cooling step S5, a screening and classification step S6 can be further included: the light particles obtained by cooling are classified and stored according to their unit weight and particle size. Before the light particles leave the factory, It must also be tested by the Toxicity Characteristic Dissolution Program (TCLP) to assess that it meets the national dissolution standards, and then it becomes a finished product that can be sold.

The preferred embodiment of the present invention is to mix waste incineration fly ash, aluminosilicate additives and other raw materials in a metered ratio to make them contain specific chemical components, and add water to granulate them into a semi-dry raw material ball , And then burned into light pellets in rotary kiln through heat treatment process. Because the preferred embodiment of the present invention uses rotary kiln system equipment to melt and sinter and solidify the heavy metals, dioxin, furan and other toxic substances in the waste incineration fly ash, decompose and stabilize the glassy solidified material formed by the melting and sintering In addition, by generating foaming gas at a high temperature containing aluminosilicate additives, the waste incineration fly ash is made into a lightweight material with small pores throughout the interior, which can be used in construction projects.

Corresponding to the above-mentioned method for manufacturing waste incineration fly ash resources to reprocess lightweight materials of the present invention, the present invention provides a manufacturing system for incineration fly ash reprocessed lightweight materials, which mainly includes a drying unit 1, a grinding unit 2, Mixing unit 3, granulating unit 4 and firing unit 5.

Provide waste incineration fly ash as raw materials and aluminosilicate as additives. The waste incineration fly ash can be fly ash or reacted ash. The aluminosilicate-containing additives have fluxing , Foaming and viscosity-increasing effects, such as reservoir silt, harbor silt, stone processing sludge, clay and other materials. The raw materials and additives are sent to the drying unit 1 for drying. The waste incineration fly ash and additives (herein mainly reservoir sludge) as raw materials are transported to the oven for drying until constant weight, as described above, The temperature of the oven is preferably between 95°C and 105°C.

The dried waste incineration fly ash and additives are transported to the grinding unit 2. The grinding unit 2 includes a crushing device 21 and a grinding device 22. The crushing device 21 may be, for example, a jaw crusher to incinerate the dried waste. The ash and additives are crushed into pieces. The grinding device 22 can be, for example, a ball mill. The crushed waste incineration fly ash and additives are respectively finely ground into powder and stored in their respective silos. The ball mill can crush the The waste incineration fly ash and additives are finely ground into powder with a median particle size D ₅₀ ≦7 microns (μm).

The above-mentioned homogenized waste incineration fly ash and additives are transported to the mixing unit 3. The mixing unit 3 is arranged downstream of the grinding unit 1, and is used to mix the homogenized waste incineration fly ash and additives with water. Masterbatch mixture. Measure and take the ground waste incineration fly ash and additives in an appropriate ratio, and mix with water to form a mixture with a moisture content of 15% to 35%, so that the non-water part of the mixture (ie, waste incineration fly ash) The mixed solid of ash and additives) may have specific and preferable chemical composition.

The mixed masterbatch mixture is conveyed to the granulation unit 4, which is arranged at the downstream end of the mixing unit 3 to receive the masterbatch mixture from the mixing unit 3 and granulate to form a raw material ball, for example The masterbatch mixture is made into spherical raw material balls with a continuous gradation of 5-20 mm, which can be granulated by a disc granulator. The granulation method can be wet-balling to avoid dust flying.

The pelletized raw material balls are transported to the firing unit 5. The firing unit 5 includes at least a double-tube rotary kiln 51 and a monitoring device 52. The double-tube rotary kiln 51 is composed of a drying preheating kiln 511 and a roasting kiln 512. It is connected in series, and the drying and preheating kiln 511 and the roasting kiln 512 are independently equipped with temperature adjustment mechanisms and speed adjustment mechanisms, so the heating temperature curves of the drying and preheating kiln 511 and roasting kiln 512 can be independently controlled and adjusted . The drying and preheating kiln 511 receives the raw meal pellets from the pelletizing unit 3 and performs the first stage firing, and the roasting kiln 512 receives the raw meal pellets from the drying and preheating kiln 511 and performs the second step at a temperature between 1100 and 1400°C. Stage firing to obtain light pellets. The double-tube rotary kiln 51 is further provided with an angle adjustment mechanism, which is electrically connected with the monitoring device 52 to adjust the inclination angle of the double-tube rotary kiln 41. The drying and preheating kiln 511 and the roasting kiln 512 are respectively provided with a gas regulating mechanism, and the gas regulating mechanism is electrically connected with the monitoring device 52 to detect and adjust the gas composition ratio in the drying and preheating kiln 511 and the roasting kiln 512.

The light weight material after firing is conveyed to the cooling unit 6, and the cooling unit 6 is arranged at the downstream end of the firing unit 5 to cool the light weight material, and the light weight material obtained by firing is cooled and annealed; preferably However, the lightweight material is cooled and annealed using a cooler according to the pre-set slow cooling curve.

The cooled light pellets are transported to a screening unit 7, where they are classified and stored according to their unit weight and particle size.

The light pellets after screening are transported to a poison detection unit 8 before leaving the factory, and the light pellets are tested for poisons, for example, the toxicity characteristic leaching procedure (TCLP) test.

Specific examples are given below to illustrate the method for preparing the lightweight material from waste incineration fly ash resources of the present invention, and to analyze its water absorption, density and strength properties. "Example 1-3"

In Examples 1-3, waste incineration fly ash, waste incineration reaction ash, and additives (in this example, reservoir sludge) were dried, crushed, and ground in the proportions shown in Table 2 below, and then Add clear water and mix to obtain a masterbatch mixture. The moisture content of the masterbatch mixture is between 15% and 25%.

The masterbatch mixture is transported to a disc granulator on a conveyor belt for granulation to form a continuous gradation of 5-15 mm of crushed raw material balls.

Then, put the raw meal balls into a double-cylinder rotary kiln for low-temperature stage firing and high-temperature stage firing at the temperature, heating time, and rotation speed shown in Table 1, to obtain light pellets S1, S2, S3.

After cooling and annealing the lightweight material S1, S2, S3, the physical properties of the product were analyzed, and the results obtained were recorded in Table 1.

Table 2 Example 1 Example 2 Example 3 Light pellets S1 S2 S3 Raw material ratio Waste incineration fly ash (wt%) 5~25 0 5~10 Waste incineration reaction ash (wt%) 0 5~25 5~10 Reservoir silt (wt%) 75~95 75~95 80~90 Water content of masterbatch mixture (%) 15~25 15~25 15~25 Average particle size of raw meal (mm) 5~15 5~15 5~15 Low-temperature firing The first temperature (℃) 60 60 60 The second temperature (℃) 650 650 650 Heating time (min) 18~25 15~25 20~25 Speed (rpm) 4~6 4~6 4~6 High-temperature firing The third temperature (℃) 950 950 950 The fourth temperature (℃) 1350 1400 1350 Time (min) 25~45 30~50 30~50 Speed (rpm) 1~2 1~2 1~2 Product properties Loose unit weight (kg/m ³ ) 450~700 450~700 450~700 Particle size (mm) 5~20 5~20 5~20 Particle density (g/cm ³ ) 0.8~1.4 0.8~1.4 0.8~1.4 Water absorption rate (%) 10~16 10~16 10~16 Cylinder compression strength (Mpa) 3~8 3~8 3~8

From the results in Table 2, it can be found that the loose unit weight of the light pellets S1, S2, and S3 prepared in Examples 1-3 of the present invention is between 450 and 700 kg/m ³ and the particle density is between 0.8 and 1.4 g. /cm ³ ; the water absorption rate is between 10-16%; the cylinder compressive strength is between 3-8Mpa, which is suitable for general construction projects or gardening and planting materials.

The preferred embodiment of the present invention is to mix waste incineration fly ash, aluminosilicate additives and other raw materials according to the metered ratio to make it contain specific chemical components, and add water to granulate into a semi-dry raw material ball , And then burned into light pellets in rotary kiln through heat treatment process. Because the preferred embodiment of the present invention uses rotary kiln system equipment to melt and sinter and solidify the heavy metals, dioxin, furan and other toxic substances in the waste incineration fly ash, decompose and stabilize in the glassy solidified material formed by melting and sintering In addition, by generating foaming gas at a high temperature containing aluminosilicate additives, the waste incineration fly ash is made into a lightweight material with small pores throughout the interior, which can be used in construction projects.

In summary, the preferred embodiment of the present invention is effective in stabilizing the waste incineration and flying ash, and the light-weight material obtained by it can also obtain substantial economic benefits, which is beneficial to the people’s livelihood, construction and environmental protection of the country. It is very positive. However, as shown in the above description, drawings and table, it is one of the preferred embodiments of the present invention, and is not limited to the present invention. Therefore, all the structures, devices, features, etc. of the present invention are similar and similar All of them should fall within the creation purpose of the invention and the scope of the patent application.

1: Drying unit

2: Grinding unit

3: Mixing unit

4: Granulation unit

5: Firing unit

6: Cooling unit

7: Screening unit

8: Poison detection unit

51: Double barrel rotary kiln

52: Monitoring device

511: Drying and preheating kiln

512: roasting kiln

Fig. 1 is a flow chart of a preferred embodiment of the manufacturing method of waste incineration fly ash resource recycling lightweight material according to the present invention. Fig. 2 is a system block diagram of an embodiment of the manufacturing system of the incineration fly ash re-processed lightweight material according to the present invention.

S1~S6: steps

Claims (7)

A manufacturing method for regenerating lightweight material from waste incineration fly ash resources, which includes: master batch mixture preparation steps: putting dried waste incineration fly ash powder and additives into a mixing unit, and then adding water to mix to form a moisture content The masterbatch mixture in the range of 15%~35%; the granulation step: the masterbatch mixture is put into a granulation unit to make raw pellets with a particle size distribution of 2-20mm; and the firing step: The first raw material ball is transported to the burning unit for low-temperature stage burning and high-temperature stage burning in order to obtain light pellets; wherein the weight ratio of the waste incineration fly ash to the additive is 5wt%: 95wt%~25wt%: 75wt%, and the waste incineration fly ash and the additive are powders with a median particle size D ₅₀ ≦ 7 microns (μm) respectively; the additive contains at least aluminosilicate; the low temperature The conditions of the stage firing are: in the first predetermined time interval (t1), the temperature is raised from the first temperature (T1) to the second temperature (T2), and the rotation speed is in the range of 2-6 rpm; the high-temperature stage firing The condition of is: increase the temperature from the third temperature (T3) to the fourth temperature (T4) in the second predetermined time interval (t2); and t1, t2, T1, T2, T3, and T4 meet the following relations respectively: 15min≦t1≦60min, 25min≦t2≦50min, and 0.6≦t1/t2≦2.4; 40℃≦T1≦700℃, 40℃≦T2≦700℃, and T1≦T2; 600℃≦T3≦1250℃, 600℃≦T4≦1250℃, and T3≦T4. For example, the manufacturing method of waste incineration fly ash resources to reproduce lightweight materials as described in claim 1, wherein the waste incineration fly ash is fly ash, and the non-aqueous part of the mixture contains the following components: Silicon dioxide 49~58wt%, aluminum oxide 21~23wt%, iron oxide 6~7wt%, calcium oxide 5~11wt%, magnesium oxide 2~3wt%, sodium oxide less than 1wt%, oxygen Potassium is less than 1wt% and organic matter is 1~5wt%. The above proportion is the weight percentage of each component in the non-water part of the mixture. The manufacturing method of regenerating lightweight material from waste incineration fly ash resources as described in claim 1, wherein the waste incineration fly ash is reacted ash, and the non-aqueous part of the master batch contains the following components ：Silicon dioxide 44~56wt%, aluminum oxide 17~22wt%, iron oxide 5~7wt%, calcium oxide 6~15wt%, magnesium oxide 1~2wt%, sodium oxide less than 1wt%, potassium oxide less than 1.5wt%, organic matter 1~5wt%, the above proportion is the weight percentage of each component in the non-water part of the mixture. For example, the method for making lightweight material from waste incineration fly ash resources described in claim 1, wherein the waste incineration fly ash is fly ash and reaction ash, and the non-aqueous part of the master batch contains the following components: Silica 45~56wt%, aluminum trioxide 18~22wt%, iron trioxide 6~7wt%, calcium oxide 6~14wt%, magnesium oxide 1~2wt%, sodium oxide less than 1wt%, potassium oxide less than 1.5 wt%, organic matter 1~5wt%, the above ratio is the weight percentage of each component in the non-water part of the mixture. The method for producing lightweight material from waste incineration fly ash resources as described in claim 1, wherein the additive is any one of reservoir sludge, water purification sludge, stone processing sludge, clay, and mixtures thereof. Such as the method for making lightweight material from waste incineration fly ash resources as described in claim 1, wherein the lightweight material is used for general construction projects or horticultural planting materials. As described in any one of Claims 1 to 6, the method for preparing lightweight material from waste incineration fly ash resources, wherein the particle density of the lightweight material is 0.3 g/cm ³ ~1.8 g/cm ³ .

Images