JPS646136B2 - - Google Patents
Info
- Publication number
- JPS646136B2 JPS646136B2 JP117384A JP117384A JPS646136B2 JP S646136 B2 JPS646136 B2 JP S646136B2 JP 117384 A JP117384 A JP 117384A JP 117384 A JP117384 A JP 117384A JP S646136 B2 JPS646136 B2 JP S646136B2
- Authority
- JP
- Japan
- Prior art keywords
- specific gravity
- pellets
- weight
- shale
- firing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000010304 firing Methods 0.000 claims description 11
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 9
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 8
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 239000008188 pellet Substances 0.000 description 18
- 230000005484 gravity Effects 0.000 description 16
- 238000000034 method Methods 0.000 description 10
- 239000000654 additive Substances 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- 239000002994 raw material Substances 0.000 description 6
- 238000010521 absorption reaction Methods 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 3
- 238000005469 granulation Methods 0.000 description 3
- 230000003179 granulation Effects 0.000 description 3
- 229910052595 hematite Inorganic materials 0.000 description 3
- 239000011019 hematite Substances 0.000 description 3
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 230000003750 conditioning effect Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- 239000010802 sludge Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 239000004035 construction material Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 230000009970 fire resistant effect Effects 0.000 description 1
- 238000005187 foaming Methods 0.000 description 1
- 239000004088 foaming agent Substances 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
Landscapes
- Porous Artificial Stone Or Porous Ceramic Products (AREA)
- Carbon And Carbon Compounds (AREA)
Description
本発明は軽量骨材の製造方法の改良法に関する
ものである。
従来頁岩を原料とする軽量骨材の製造方法とし
ては、該頁岩を粉砕して100メツシユ以下とした
のちこれに適量の水を加えてペレタイザーで造
粒、乾燥、焼成する方法が実用されている。
しかしながら、この方法で得られた焼成ペレツ
トは、骨材として充分な圧壊強度（直径７mmで50
Kg以上）と耐吸水率（５〜７重量％）は得られる
が、見掛比重が1.25程度と比較的高いという問題
点があつた。
近年建築材の軽量化と断熱性能の強化が要望さ
れており、又耐火性で強度がある低比重の骨材の
出現が待たれているのが現状である。
そこで上記の見掛比重（以下単に比重と略称す
る）を効率よく大幅に低下させたとする新規な軽
量骨材の製造方法（特開昭50−98923号公報）が
提案されている。
この方法は、頁岩又は石泥100部に対しパルプ
スラツジ10〜30部を添加混合して粒状化し、これ
を800〜1150℃にて焼成することにより比重約0.7
の骨材を得たとするものである。
しかし、上記の方法で使用する添加剤は、製紙
工場で発生する水分含有率85重量％程度のパルプ
ヘドロ（特開昭50−105718号公報、実施例１参
照）を大型ドライヤーで膨大な水分を蒸発させ、
水分含有率10重量％程度まで乾燥して使用しなけ
ればならず、非実用的なコスト高となるだけでな
く、増量材としても全く寄与しない等の欠点があ
つた。
本発明の目的は、上記の欠点を解消し、得られ
る焼成物の比重を、更に小さくすることのできる
骨材の製造方法を提供することにある。
この目的を達成するため本願発明者等は鋭意研
究の結果、微粉末状の頁岩に、発泡剤として知ら
れる炭化硅素と共に用いれば、焼成時に一酸化炭
素を発生すると思われる酸化鉄、好ましくは酸化
第二鉄の所定量とを夫々超微粉末として、添加混
合し、ペレツトとして焼成すると著るしく比重が
低下することを見出し本発明の方法に到達したも
のである。
即ち本発明の方法は、主原料の頁岩の平均粒度
を15μｍ以下とし、これに平均粒度10μｍ以下の
酸化鉄、好ましくは酸化第二鉄及び炭化硅素を内
割りで２〜10重量％（Fe2O3）、0.1〜2.5重量％
（SiC）を夫々添加、混合したのち調湿して造粒
し、焼成するというものである。
本発明法において、頁岩及び添加剤を常識外と
思われる微細な粒度まで微粉砕する理由は、これ
は本発明法の主たる特徴であるが、焼成時にペレ
ツト内部の反応性を良くし微細で均一な気泡を生
成させるためである。これより粗粒のものを使用
すると他の条件、例えば焼成時の酸素雰囲気や温
度、焼成時間、酸化第二鉄、炭酸塩、アルミナ等
通常の各種の添加剤の添加等をいかに工夫して
も、本発明法のような効果は得られない。
次に添加剤として、頁岩に対し内割りで酸化鉄
を２〜10重量％、炭化硅素を0.1〜2.5重量％混入
するのは、ともにこれ以下では焼成ペレツトの比
重低下が顕著でなく、又、これ以上添加しても効
果の向上は望まれないからである。特に炭化硅素
は多過ぎると異常発泡が見られるので注意を要す
る。この炭化硅素の代りに窒化硅素の添加も有効
である。
次にペレツトの焼成温度は高温とするほど、焼
成ペレツトの比重は軽くなる傾向を示すが、あま
り高温になるとペレツトの表面まで溶融し、ロー
タリーキルンでの焼成中にペレツト同志が融着す
る現象を示すので1120℃以下1050℃以上で、高温
ゾーンの滞留時間を20〜30分程度とするのが好ま
しい。又この際の炉内雰囲気の酸素含有量は焼成
物の排出側で８〜10容量％、原料供給側から排出
側に至る中間は12〜13容量％程度でよく、従来の
ように極力酸素濃度を制限する必要はない。
そのほか原料ならびに添加物の粉砕、混合、そ
してこれに適当量の水を加えて調湿後の造粒操作
等については通常の機器、例えば粉砕はチユーブ
ミル、造粒はパン型ペレタイザー等を用い特に制
限された操作を要しない。
本発明の方法によれば、ペレツトの直径や形状
（円筒形、楕円形等）の如何に関らず、確実に比
重0.55前後の軽量骨材を製造することが可能とな
る。
この軽量骨材の大きさについては、制約されな
いが、通常直径５mmから20mmのものが実用され、
比重が同じならば直径が大きくなるほど圧壊強度
は大きくなり、逆に吸水率は減少するが、本発明
法により得られる平均粒径約７mmのほぼ球状の焼
成ペレツトでは、圧壊強度が約25Kg程度、吸水率
は１〜４重量％程度と単に比重が軽量であるだけ
でなく骨材として具備すべき性状においても優れ
たものということができる。
以下実施例について説明する。
実施例 １
頁岩を、シングルトグルクラツシヤーで粗砕し
たのちロータリーキルンタイプのドライヤーで乾
燥し、次いでインペラブレーカーにかけて２次粉
砕し、更にチユーブミル（大塚鉄工製、直径2.5
ｍ、長さ5.6ｍ、ボールサイズ50〜75mm、回転数
20r.p.m.）を用い平均粒径が15μｍ以下となるま
で微粉砕した。次にこの主原料60Kgに、添加剤と
して平均粒径5μｍ以下のヘマタイト（株式会社
鉄原製Fe2O3粉末）を内割りで７重量％と、平均
粒径5μｍ以下の炭化硅素の所定量を夫々添加し、
これを容量0.03m3のコンクリートミキサーで混合
したのち常法により、調湿、パン型ペレタイザー
による造粒を平均粒径が約５mmとなるようにして
行なつた。
該グリーンペレツトは乾燥器で充分な乾燥を行
なつたのち、内径500mm、長さ4000mm、傾斜度4.5
％、回転数3r.p.m.、加熱源はプロパンバーナー
のテストキルンで炉出口側温度1080〜1115℃、入
口側温度630℃、炉出口側と炉入口側の酸素濃度
は夫々８〜９容量％、12〜13容量％に保持し、該
ペレツトの焼成帯滞留時間を20分間となるように
して、１分間に300ｇ給鉱して各30分間該ペレツ
トの焼成を行なつた。
焼成後のペレツトは、放冷したのち平均粒径を
測定、その他の物性についてはJISA1135に従つ
て測定した。尚使用した頁岩の組成は第１表に示
したものを使用した。その結果をそれぞれの平均
値として第１表に示す。
尚原料及び添加物の粒度は光透過式粒度計で測
定した。
The present invention relates to an improved method for producing lightweight aggregate. The conventional method for producing lightweight aggregates using shale as a raw material is to crush the shale to a size of 100 mesh or less, add an appropriate amount of water to it, granulate it with a pelletizer, dry it, and fire it. . However, the fired pellets obtained by this method have sufficient crushing strength (50
Kg or more) and water absorption resistance (5 to 7% by weight), but there was a problem that the apparent specific gravity was relatively high at about 1.25. In recent years, there has been a demand for lighter weight construction materials and stronger heat insulating performance, and the current situation is that fire-resistant, strong, low specific gravity aggregates are awaited. Therefore, a new method for producing lightweight aggregates has been proposed (Japanese Unexamined Patent Publication No. 50-98923), which efficiently and significantly reduces the above-mentioned apparent specific gravity (hereinafter simply referred to as specific gravity). In this method, 10 to 30 parts of pulp sludge is added to 100 parts of shale or stone mud, granulated, and then calcined at 800 to 1150°C, with a specific gravity of approximately 0.7.
It is assumed that the aggregate of However, the additive used in the above method uses a large dryer to evaporate the pulp sludge (see Example 1 of JP-A-50-105718), which has a water content of about 85% by weight, generated in a paper mill. let me,
It has to be used after being dried to a water content of about 10% by weight, which not only results in impractically high costs, but also has drawbacks such as not contributing at all as a filler. An object of the present invention is to provide a method for producing aggregate that can eliminate the above-mentioned drawbacks and further reduce the specific gravity of the resulting fired product. In order to achieve this objective, the inventors of the present invention have conducted intensive research and found that when used with finely powdered shale together with silicon carbide, known as a foaming agent, iron oxide, preferably iron oxide, which is thought to generate carbon monoxide during firing, The method of the present invention was developed based on the discovery that when a predetermined amount of ferric iron is added and mixed in the form of ultrafine powder, and fired as pellets, the specific gravity is significantly reduced. That is, in the method of the present invention, the average particle size of shale as the main raw material is 15 μm or less, and 2 to 10% by weight (Fe 2 O3 ), 0.1-2.5% by weight
(SiC) is added and mixed, then the humidity is adjusted, granulated, and fired. In the method of the present invention, the reason why the shale and additives are pulverized to a fine particle size that seems to be unconventional is that this is the main feature of the method of the present invention, but it improves the reactivity inside the pellet during firing and produces fine and uniform pellets. This is to generate bubbles. If coarser grains are used, no matter how much other conditions such as oxygen atmosphere and temperature during firing, firing time, addition of various usual additives such as ferric oxide, carbonate, alumina, etc. , the effect like the method of the present invention cannot be obtained. Next, as additives, 2 to 10% by weight of iron oxide and 0.1 to 2.5% by weight of silicon carbide are mixed into the shale, because if both are below this, the specific gravity of the fired pellets will not decrease significantly. This is because even if more than this is added, no improvement in the effect is expected. In particular, care must be taken when using too much silicon carbide as abnormal foaming may occur. It is also effective to add silicon nitride instead of silicon carbide. Next, the higher the pellet firing temperature is, the lighter the specific gravity of the fired pellets tends to be. However, if the temperature is too high, the pellets will melt to the surface, and the pellets will fuse together during firing in the rotary kiln. Therefore, it is preferable that the temperature is below 1120°C and above 1050°C, and the residence time in the high temperature zone is about 20 to 30 minutes. In addition, the oxygen content of the atmosphere inside the furnace at this time may be 8 to 10% by volume on the discharge side of the fired product, and 12 to 13% by volume in the middle from the raw material supply side to the discharge side, and as in the past, the oxygen concentration should be kept as low as possible. There is no need to limit it. In addition, the pulverization and mixing of raw materials and additives, the addition of an appropriate amount of water to the mixture, and the granulation operation after conditioning the humidity are carried out using normal equipment, such as a tube mill for pulverization and a pan-type pelletizer for granulation, with particular restrictions. No additional operations are required. According to the method of the present invention, it is possible to reliably produce lightweight aggregates with a specific gravity of around 0.55, regardless of the pellet diameter or shape (cylindrical, elliptical, etc.). There are no restrictions on the size of this lightweight aggregate, but those with a diameter of 5 mm to 20 mm are commonly used.
If the specific gravity is the same, the larger the diameter, the greater the crushing strength, and conversely the water absorption rate decreases. However, in the case of almost spherical calcined pellets with an average particle diameter of about 7 mm obtained by the method of the present invention, the crushing strength is about 25 kg, The water absorption rate is about 1 to 4% by weight, and it can be said that it not only has a light specific gravity but also has excellent properties as an aggregate. Examples will be described below. Example 1 Shale was roughly crushed with a single toggle crusher, dried with a rotary kiln type dryer, then secondary crushed with an impeller breaker, and further crushed with a tube mill (manufactured by Otsuka Iron Works, diameter 2.5
m, length 5.6m, ball size 50-75mm, rotation speed
20 rpm) until the average particle size was 15 μm or less. Next, to 60 kg of this main raw material, 7% by weight of hematite (Fe 2 O 3 powder manufactured by Tetsuhara Co., Ltd.) with an average particle size of 5 μm or less as additives and a predetermined amount of silicon carbide with an average particle size of 5 μm or less are added. Add each of
This was mixed in a concrete mixer with a capacity of 0.03 m 3 , and then subjected to humidity conditioning and granulation using a pan-type pelletizer in a conventional manner so that the average particle size was about 5 mm. After thoroughly drying the green pellets in a dryer, the green pellets have an inner diameter of 500 mm, a length of 4000 mm, and a slope of 4.5.
%, rotation speed 3 r.pm, heat source was a propane burner test kiln, temperature at the furnace outlet side was 1080-1115℃, temperature at the inlet side was 630℃, oxygen concentration at the furnace outlet side and furnace inlet side was 8-9% by volume, respectively. The pellets were maintained at 12 to 13% by volume, and the residence time of the pellets in the firing zone was 20 minutes, and the pellets were fired for 30 minutes each while feeding 300 g of ore per minute. After the fired pellets were allowed to cool, the average particle size was measured, and other physical properties were measured in accordance with JISA1135. The composition of the shale used was shown in Table 1. The results are shown in Table 1 as the respective average values. The particle sizes of the raw materials and additives were measured using a light transmission granulometer.
【表】【table】
【表】
表註、※は焼成帯温度が低目の場合の参
考値である。
第１表より明らかなように、実験No.４、５、６
に示すように比重0.5台のものが得られ、圧壊強
度及び吸水率も満足すべきものであつた。尚、圧
壊強度は圧縮試験機によつて圧壊された時の荷重
値の試料100個の平均値である。
実施例 ２
添加剤として炭化硅素の添加量を内割りで0.5
重量％、実施例１で使用したヘマタイトの添加量
を内割りで1.0〜10.0重量％とし、テストキルン
焼成帯の温度を1115℃とした以外は実施例１と同
様にして焼成ペレツトを製造し、その性状を測定
した。その結果を第２表に示す。[Table] Note: * is a reference value when the firing zone temperature is low.
As is clear from Table 1, Experiment Nos. 4, 5, and 6
As shown in Figure 2, a product with a specific gravity of 0.5 was obtained, and its crushing strength and water absorption rate were also satisfactory. Note that the crushing strength is the average value of the load value of 100 samples when crushed by a compression tester. Example 2 The amount of silicon carbide added as an additive was divided into 0.5
Calcined pellets were produced in the same manner as in Example 1, except that the amount of hematite used in Example 1 was 1.0 to 10.0% by weight, and the temperature of the test kiln firing zone was 1115 ° C. Its properties were measured. The results are shown in Table 2.
【表】
第２表を見て判るように、実験No.７のようにヘ
マタイト（Fe2O3）の添加量が少ないものは比重
が比較的大きい値を示したが、それ以外の比重は
0.5台であつた。
実験No.12はヘマタイトの添加量が多いにもかか
わらずむしろ比重が大きくなり、これ以上の添加
は逆に有害であることを示した。[Table] As can be seen from Table 2, samples with a small amount of hematite (Fe 2 O 3 ) added, such as in Experiment No. 7, had relatively high specific gravity values, but other specific gravity values were
It was 0.5 units. Experiment No. 12 showed that despite the large amount of hematite added, the specific gravity actually increased, indicating that adding more than this was actually harmful.
Claims (1)
ｍ以下の酸化鉄及び炭化硅素を夫々内割りで２〜
10重量％、0.1〜2.5重量％添加し混合したのち、
造粒し次いで焼成することを特徴とする軽量骨材
の製造方法。 ２ 焼成温度は1050〜1120℃であることを特徴と
する特許請求の範囲１項記載の軽量骨材の製造方
法。[Claims] 1. Shale with an average grain size of 15 μm or less, an average grain size of 10 μm
m or less iron oxide and silicon carbide each divided into 2~
After adding and mixing 10% by weight and 0.1 to 2.5% by weight,
A method for producing lightweight aggregate, characterized by granulating and then firing. 2. The method for producing lightweight aggregate according to claim 1, wherein the firing temperature is 1050 to 1120°C.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP117384A JPS60145941A (en) | 1984-01-06 | 1984-01-06 | Manufacture of lightweight aggregate |
| DK003985A DK161829C (en) | 1984-01-06 | 1985-01-03 | PROCEDURE FOR THE MANUFACTURING OF EASY SUPPLEMENTARY MATERIALS |
| KR1019850000021A KR850005384A (en) | 1984-01-06 | 1985-01-05 | Method of manufacturing crushed stone for concrete |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP117384A JPS60145941A (en) | 1984-01-06 | 1984-01-06 | Manufacture of lightweight aggregate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60145941A JPS60145941A (en) | 1985-08-01 |
| JPS646136B2 true JPS646136B2 (en) | 1989-02-02 |
Family
ID=11494039
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP117384A Granted JPS60145941A (en) | 1984-01-06 | 1984-01-06 | Manufacture of lightweight aggregate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60145941A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2550839Y2 (en) * | 1991-06-14 | 1997-10-15 | 株式会社村田製作所 | Magnetic sensor |
-
1984
- 1984-01-06 JP JP117384A patent/JPS60145941A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60145941A (en) | 1985-08-01 |
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