JPS6362559B2 - - Google Patents
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- Publication number
- JPS6362559B2 JPS6362559B2 JP17320683A JP17320683A JPS6362559B2 JP S6362559 B2 JPS6362559 B2 JP S6362559B2 JP 17320683 A JP17320683 A JP 17320683A JP 17320683 A JP17320683 A JP 17320683A JP S6362559 B2 JPS6362559 B2 JP S6362559B2
- Authority
- JP
- Japan
- Prior art keywords
- coal
- low
- weight
- temperature
- steam
- 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
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- 239000003245 coal Substances 0.000 claims description 33
- 238000000034 method Methods 0.000 claims description 18
- 238000011282 treatment Methods 0.000 claims description 17
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 8
- 238000001035 drying Methods 0.000 claims description 8
- 229910052760 oxygen Inorganic materials 0.000 claims description 8
- 239000001301 oxygen Substances 0.000 claims description 8
- 238000000748 compression moulding Methods 0.000 claims description 6
- 239000007789 gas Substances 0.000 claims description 5
- 239000003077 lignite Substances 0.000 claims description 5
- 238000002407 reforming Methods 0.000 claims description 5
- 229920006395 saturated elastomer Polymers 0.000 claims description 5
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 229910052757 nitrogen Inorganic materials 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 16
- 230000003647 oxidation Effects 0.000 description 9
- 238000007254 oxidation reaction Methods 0.000 description 9
- 238000010438 heat treatment Methods 0.000 description 7
- 230000002269 spontaneous effect Effects 0.000 description 6
- 239000004484 Briquette Substances 0.000 description 5
- 239000003610 charcoal Substances 0.000 description 4
- 238000002485 combustion reaction Methods 0.000 description 4
- 239000011230 binding agent Substances 0.000 description 3
- 230000018044 dehydration Effects 0.000 description 3
- 238000006297 dehydration reaction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000007654 immersion Methods 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 239000003415 peat Substances 0.000 description 3
- 239000003476 subbituminous coal Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000002802 bituminous coal Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- OLBVUFHMDRJKTK-UHFFFAOYSA-N [N].[O] Chemical compound [N].[O] OLBVUFHMDRJKTK-UHFFFAOYSA-N 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000004939 coking Methods 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000000921 elemental analysis Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 238000011866 long-term treatment Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000009738 saturating Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
Landscapes
- Solid Fuels And Fuel-Associated Substances (AREA)
Description
本発明は低品位炭の改質方法に関し、詳しくは
泥炭、褐炭、亜瀝青炭などの低品位炭の耐水性お
よび水中浸漬後の圧漬強度を向上させると共に、
含水率を低減させ、かつ活性を低下させて自然発
火の防止を図り、輸送性、貯蔵性を向上させる低
品位炭の改質方法に関する。
褐炭などの低品位炭は含水率が高いため、その
輸送が不経済であるばかりでなく、活性が強いた
め輸送中や貯蔵中などに自然発火を起こし易い等
の理由で、その利用範囲は山元近傍に限られてい
る。
このような事情に鑑み、これら低品位炭の脱水
および自然発火の防止に関する研究が行なわれ、
種々の提案がなされている。たとえば、脱水法と
しては蒸発法、機械的脱水法などが知られて
おり、また自然発火防止法としては空気遮断法
（水中貯炭、石炭表面コーテイング、貯炭表面被
覆、圧縮貯炭、不活性ガスシールなど）、冷却
法、微粉炭の除去、プリケツト化などの対策
が行なわれている。具体的には乾燥後水蒸気存在
下で加熱処理し、大気圧下で加熱成形して練炭と
する方法（特開昭56―104996号公報）、乾燥後急
速加熱し、次いで急速冷却する方法（特開昭56―
149494号公報）などがある。
しかしながら、これらの方法は十分な効果が得
られなかつたり、操作が煩雑であつたりして必ず
しも満足すべき方法ではなかつた。
そこで本発明者らは既に高温下に圧縮成形する
方法（特公昭62―47479号公報）、乾燥後原料炭を
酸化処理して自然発火を防止する方法（特開昭59
―74189号公報）を提案している。さらに続けて
本発明者らは石炭を実質的に含水率０重量％にな
るまで乾燥し、次いで成形温度まで急速加熱し、
高圧下で圧縮成形し、成形物を酸化処理する方法
（特開昭59―161491号公報）を提案している。
本発明者らは、さらに低品位炭の改質方法につ
いて改良を重ねた結果、上記酸化処理後にスチー
ム処理を行なうことにより、成形炭の耐水性およ
び水中浸漬後の圧漬強度を一層向上させることが
できることを見出し、本発明を完成するに到つ
た。
すなわち、本発明は低品位炭を85〜150℃で実
質的に含水率０重量％になるまで乾燥後、200〜
400℃の成形温度まで10分以内で急速加熱し、こ
の温度において直ちに１〜5t／cm2の圧力で圧縮成
形し、得られた成形物を100〜200℃で酸素濃度１
〜21容量％の空気あるいは酸素と窒素の混合ガス
を用いて酸化処理し、次いで80〜150℃の飽和水
蒸気中でスチーム処理することを特徴とする低品
位炭の改質方法を提供するものである。
石炭の中では泥炭が最も自然発火しやすく、以
下褐炭、亜瀝青炭、瀝青炭の順であることが知ら
ている。また、泥炭、褐炭、亜瀝青炭、瀝青炭な
どの低品位炭は含水率が高いため、輸送効率が悪
いものである。したがつて、本発明ではこれらの
低品位炭を対象としてその改質を行なうものであ
る。
本発明を実施するにあたつて、原料炭は予め粉
砕して粒状としておくことが望ましく、特に粒径
を３mm以下としておくことが好ましい。また、低
品位炭は天日乾燥などにより乾燥して含水率を15
〜20重量％まで低減させておくことが望ましい。
低品位炭の乾燥は85〜150℃の温度で加熱する
ことにより行ない、好ましくは窒素ガス等の不活
性ガス中で、実質的に含水率が０重量％となるま
で行なう。乾燥時間は低品位炭の種類、加熱温度
などを考慮して決定する。この乾燥により低品位
炭中の水分の大部分が除かれ、さらに可燃性ガス
の一部も除去される。
乾燥した低品位炭は、次に10分以内、好ましく
は５〜７分で200〜400℃の温度まで急速に加熱す
る。このような急速加熱を行なうのは、高温で長
時間処理することによる成形性の低下を防止する
ためである。
急速加熱後、200〜400℃の温度において１〜
5t／cm2、好ましくは２〜3t／cm2の圧力にて瞬時に
圧縮成形する。また、通常は圧縮成形する場合、
外部よりピツチ等のバインダーを加えることが必
要であるが、本発明においては自己副生タールを
バインダーとする為、外部バインダーを必要とし
ない。なお、一般に成形温度が高いほど耐水性が
向上する傾向がある。
続いて、高温圧縮成形された石炭の酸化処理を
行なう。この操作は耐自然発火性を改善すること
を目的としており、100〜200℃の温度で行なうと
すぐれた効果が得られる。酸化処理は酸素濃度１
〜21容量％、好ましくは４〜10容量％で30分〜５
時間、好ましくは２〜３時間行なう。酸化処理は
空気を用いて行なうこともできるが、望ましくは
酸素と窒素を所定割合に混合した混合ガスを使用
する。
上記酸化処理後、スチーム処理を行なう。スチ
ーム処理は80〜150℃、好ましくは90℃の飽和湿
度中で２〜８時間行なう。なお、成形炭に対して
酸化処理とスチーム処理を同時に施しても差支え
ない。このスチームによる表面処理により、成形
炭の表面が疎水化され、成形炭に耐水性をもたせ
ることができる。
本発明の方法を適用した石炭は100時間水中に
浸漬した後の圧漬強度が100Kg／cm以上と耐水性
が高く、雨ざらしになつても形がくずれず、しか
も水中浸漬後の圧漬強度も高く、取扱いや貯蔵が
容易である。本発明の方法を適用した石炭は含水
率が著減しており、しかも原炭や豪州ブリケツト
と比較してすぐれた耐自然発火性、耐発塵性を有
しており、粉砕してもこの性質を十分に維持し得
る。また、上記の如く圧漬強度が大きく、しかも
かさ密度も通常1.1g／cm3と大きいため、輸送効率
もきわめて高いものである。さらに燃料として用
いた場合、発熱量が高く燃料用炭として好適な性
状を有している。
次に、本発明の実施例を示す。
実施例 １〜６
豪州ヤルーン炭250gを３mm以下に粉砕し、窒
素ガス雰囲気中で含水率０重量％となるまで120
℃で乾燥した。乾燥には、約３時間要した。その
後、その乾燥炭（性状を第１表に示す。）8gを内
径25mmφの金型中に入れ、第２表に示す時間内に
所定の成形温度まで急速加熱し、次いで3t／cm2の
圧縮圧で瞬時に成形を行ない、直径25mm、厚み
1.4mmの成形炭を成形した。しかる後、成形炭
200gを充填塔に仕込み、500ml／分の流量の酸素
濃度６容量％の酸素―窒素混合ガス中で150℃の
温度で３時間酸化処理を行なつた。酸化処理後、
成形炭を90℃飽和湿度中でスチーム処理した。こ
のスチーム処理は、100℃の温浴でフラスコ内の
蒸留水を90℃に加熱し、フラスコ中を水蒸気で飽
和させ、この飽和水蒸気中に成形炭を放置するこ
とにより行なつた。結果を第２表に示す。なお、
実施例２、３、５および６については水中に100
時間浸漬して耐水性の評価を行なつた。
比較例 １〜６
実施例１〜６において、酸化処理、スチーム処
理のいずれか一方もしくは両方の処理を行なわな
かつたこと以外は実施例１〜６と同様に行なつ
た。結果を第２表に示す。なお、比較例２、３、
５および６については水中に100時間浸漬して耐
水性の評価を行なつた。
第１表
ａ） 工業分析としての乾燥炭の分析値（ドライ
ベース）
灰分： 1.2重量％
揮発分：50.9重量％
固定炭素：47.9重量％
ｂ） 元素分析（ドライアツシユフリー）
炭素：64.0重量％
水素： 4.5重量％
窒素： 1.0重量％
酸素：30.3重量％
硫黄： 0.2重量％
The present invention relates to a method for reforming low-rank coal, and more specifically, improves the water resistance and compaction strength of low-rank coal such as peat, lignite, and sub-bituminous coal after immersion in water, and
The present invention relates to a method for reforming low-rank coal that reduces moisture content and activity, prevents spontaneous combustion, and improves transportability and storability. Low-grade coal such as lignite has a high moisture content, which makes it uneconomical to transport.It is also highly active and tends to spontaneously ignite during transportation and storage. Limited to nearby areas. In view of these circumstances, research has been conducted on dehydration of these low-rank coals and prevention of spontaneous combustion.
Various proposals have been made. For example, evaporation methods and mechanical dehydration methods are known as dehydration methods, and air blocking methods (underwater coal storage, coal surface coating, coal storage surface coating, compressed coal storage, inert gas sealing, etc.) are known as methods to prevent spontaneous combustion. ), cooling methods, removal of pulverized coal, and precketing. Specifically, methods include a method in which drying is then heat-treated in the presence of steam, and heat-molded under atmospheric pressure to form briquettes (Japanese Patent Application Laid-Open No. 104996/1983); 1977-
149494). However, these methods are not always satisfactory because they do not provide sufficient effects or require complicated operations. Therefore, the present inventors have already developed a method of compression molding under high temperature (Japanese Patent Publication No. 62-47479), and a method of oxidizing coking coal after drying to prevent spontaneous combustion (Japanese Patent Publication No. 59/1989).
- Publication No. 74189). Further, the present inventors dried the coal until the moisture content was substantially 0% by weight, then rapidly heated it to the forming temperature,
We have proposed a method of compression molding under high pressure and oxidizing the molded product (Japanese Patent Application Laid-open No. 161491/1983). As a result of further improvements in the method for reforming low-rank coal, the present inventors have found that by performing steam treatment after the above-mentioned oxidation treatment, the water resistance of the briquette coal and the pressing strength after immersion in water are further improved. The inventors have discovered that this can be done, and have completed the present invention. That is, in the present invention, after drying low-rank coal at 85 to 150°C until the water content becomes substantially 0% by weight,
Rapid heating to a molding temperature of 400℃ within 10 minutes, compression molding at this temperature immediately at a pressure of 1 to 5 t/ cm2 , and the resulting molded product at 100 to 200℃ with an oxygen concentration of 1
The present invention provides a method for reforming low-rank coal, which is characterized by oxidation treatment using ~21% by volume of air or a mixed gas of oxygen and nitrogen, and then steam treatment in saturated steam at 80 to 150°C. be. It is known that among coals, peat is the most likely to spontaneously ignite, followed by lignite, subbituminous coal, and bituminous coal. In addition, low-grade coal such as peat, lignite, sub-bituminous coal, and bituminous coal has a high moisture content and therefore has poor transportation efficiency. Therefore, in the present invention, these low-rank coals are targeted for modification. In carrying out the present invention, it is desirable that the raw coal be pulverized in advance into granules, and it is particularly preferable that the particle size is 3 mm or less. In addition, low-grade coal is dried in the sun to reduce its moisture content to 15%.
It is desirable to reduce the amount to ~20% by weight. Drying of the low-rank coal is carried out by heating at a temperature of 85 to 150°C, preferably in an inert gas such as nitrogen gas, until the water content becomes substantially 0% by weight. The drying time is determined by considering the type of low-grade coal, heating temperature, etc. This drying removes most of the moisture in the low-rank coal and also removes some of the combustible gases. The dried low rank coal is then rapidly heated to a temperature of 200-400°C within 10 minutes, preferably 5-7 minutes. The reason for performing such rapid heating is to prevent deterioration in moldability due to long-term treatment at high temperatures. After rapid heating, at a temperature of 200 to 400℃
Compression molding is performed instantly at a pressure of 5t/cm 2 , preferably 2 to 3t/cm 2 . In addition, when compression molding is usually performed,
Although it is necessary to add a binder such as pitch from the outside, the present invention does not require an external binder because the self-by-product tar is used as the binder. In general, the higher the molding temperature, the better the water resistance tends to be. Subsequently, the high-temperature compression molded coal is oxidized. This operation is aimed at improving spontaneous ignition resistance, and excellent effects are obtained when carried out at temperatures of 100-200°C. Oxidation treatment has an oxygen concentration of 1
~21% by volume, preferably 4-10% by volume for 30 minutes ~5
The heating time is preferably 2 to 3 hours. Although the oxidation treatment can be performed using air, it is preferable to use a mixed gas containing oxygen and nitrogen in a predetermined ratio. After the above oxidation treatment, a steam treatment is performed. The steam treatment is carried out at 80 to 150°C, preferably at 90°C and at saturated humidity for 2 to 8 hours. Note that the oxidation treatment and the steam treatment may be applied to the briquette coal at the same time. By this surface treatment with steam, the surface of the briquette charcoal is made hydrophobic, and the briquette charcoal can be made water resistant. Coal produced using the method of the present invention has high water resistance, with a pressure strength of 100 kg/cm or more after being immersed in water for 100 hours, and does not lose its shape even when exposed to the rain. It is expensive and easy to handle and store. Coal produced using the method of the present invention has a significantly reduced moisture content, and has superior spontaneous ignition and dust generation resistance compared to raw coal and Australian briquettes. properties can be sufficiently maintained. Furthermore, as mentioned above, it has a high pressing strength and a bulk density of usually 1.1 g/cm 3 , so its transport efficiency is extremely high. Furthermore, when used as fuel, it has a high calorific value and has properties suitable as fuel coal. Next, examples of the present invention will be shown. Examples 1 to 6 250 g of Australian Yarun coal was crushed to 3 mm or less, and pulverized in a nitrogen gas atmosphere for 120 g until the water content reached 0% by weight.
Dry at °C. Drying took approximately 3 hours. Thereafter, 8g of the dried charcoal (properties are shown in Table 1) was placed in a mold with an inner diameter of 25mmφ, rapidly heated to the specified molding temperature within the time shown in Table 2, and then compressed to 3t/ cm2. Instantly molded using pressure, diameter 25mm, thickness
A 1.4 mm briquette was formed. After that, molded charcoal
200 g was charged into a packed column, and oxidation treatment was performed at a temperature of 150° C. for 3 hours in an oxygen-nitrogen mixed gas having an oxygen concentration of 6% by volume at a flow rate of 500 ml/min. After oxidation treatment,
The briquettes were steam-treated at 90°C and saturated humidity. This steam treatment was carried out by heating the distilled water in the flask to 90°C in a 100°C hot bath, saturating the flask with steam, and leaving the briquettes in this saturated steam. The results are shown in Table 2. In addition,
100 in water for Examples 2, 3, 5 and 6.
Water resistance was evaluated by immersion for a period of time. Comparative Examples 1 to 6 Examples 1 to 6 were carried out in the same manner as in Examples 1 to 6, except that one or both of the oxidation treatment and the steam treatment was not performed. The results are shown in Table 2. In addition, Comparative Examples 2, 3,
Samples No. 5 and No. 6 were immersed in water for 100 hours to evaluate their water resistance. Table 1 a) Analysis values of dry coal as industrial analysis (dry base) Ash content: 1.2% by weight Volatile content: 50.9% by weight Fixed carbon: 47.9% by weight b) Elemental analysis (dry ash free) Carbon: 64.0% by weight Hydrogen : 4.5% by weight Nitrogen: 1.0% by weight Oxygen: 30.3% by weight Sulfur: 0.2% by weight
【表】【table】
Claims (1)
量％になるまで乾燥後、200〜400℃の成形温度ま
で10分以内で急速加熱し、この温度において直ち
に１〜5t／cm2の圧力で圧縮成形し、得られた成形
物を100〜200℃で酸素濃度１〜21容量％の空気あ
るいは酸素と窒素の混合ガスを用いて酸化処理
し、次いで80〜150℃の飽和水蒸気中でスチーム
処理することを特徴とする低品位炭の改質方法。 ２ 低品位炭が褐炭である特許請求の範囲第１項
記載の方法。[Claims] 1. After drying low-rank coal at 85 to 150°C until the moisture content becomes substantially 0% by weight, it is rapidly heated within 10 minutes to a forming temperature of 200 to 400°C, and at this temperature, immediately Compression molding is performed at a pressure of 1 to 5 t/ cm2 , and the resulting molded product is oxidized at 100 to 200°C using air or a mixed gas of oxygen and nitrogen with an oxygen concentration of 1 to 21% by volume, and then A method for reforming low-rank coal, characterized by steam treatment in saturated steam at 150°C. 2. The method according to claim 1, wherein the low-rank coal is lignite.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17320683A JPS6065097A (en) | 1983-09-21 | 1983-09-21 | Improvement of coal |
| KR1019840000693A KR860002068B1 (en) | 1983-03-07 | 1984-02-14 | Process for modification of coal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17320683A JPS6065097A (en) | 1983-09-21 | 1983-09-21 | Improvement of coal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6065097A JPS6065097A (en) | 1985-04-13 |
| JPS6362559B2 true JPS6362559B2 (en) | 1988-12-02 |
Family
ID=15956077
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17320683A Granted JPS6065097A (en) | 1983-03-07 | 1983-09-21 | Improvement of coal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6065097A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20200135162A (en) | 2019-05-23 | 2020-12-02 | 나부테스코 가부시키가이샤 | Internal-pressure rise prevention structure of speed reducer |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11310785A (en) | 1998-04-30 | 1999-11-09 | Mitsubishi Heavy Ind Ltd | Method and apparatus for coal improvement |
| JP5511855B2 (en) | 2012-01-06 | 2014-06-04 | 三菱重工業株式会社 | Coal deactivation treatment method |
| JP5456073B2 (en) | 2012-01-06 | 2014-03-26 | 三菱重工業株式会社 | Coal deactivation processing equipment |
| JP5536247B1 (en) | 2013-03-04 | 2014-07-02 | 三菱重工業株式会社 | Coal deactivation processing equipment |
| JP5976616B2 (en) * | 2013-10-01 | 2016-08-23 | 株式会社神戸製鋼所 | Method for producing modified coal |
-
1983
- 1983-09-21 JP JP17320683A patent/JPS6065097A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20200135162A (en) | 2019-05-23 | 2020-12-02 | 나부테스코 가부시키가이샤 | Internal-pressure rise prevention structure of speed reducer |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6065097A (en) | 1985-04-13 |
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