【正文】
epower engine. Although Campbell reached a speed of over 304 miles per hour, he had great difficulty in controlling the car because a tyre burst during the first run. After his attempt, Campbell was disappointed to learn that his average speed had been 299 miles per hour. However, a few days later, he was told that a mistake had been made. His average speed had been 301 miles per hour. Since that time, racing drivers have reached speeds of over 400 miles an hour. Followings footsteps many years later, Sir Malcolm39。Lesson73 The recordholder 紀(jì)錄保持者s fishing, or eight hours in a cinema seeing the same film over and over again, is usually as far as they get. They have all been put to shame by a boy who, while playing truant, travelled 1600 miles. He hitch hiked to Dover and, towards evening, went into a boat to find somewhere to sleep. When he woke up next morning, he discovered that the boat had, in the meantime, travelled to Calais. No one noticed the boy as he crept off. From there, he hitchhiked to Paris in a lorry. The driver gave him a few biscuits and a cup of coffee and left him just outside the city. The next car the boy stopped did not take him into the centre of Paris as he hoped it would, but to Perpignan on the FrenchSpanish border. There he was picked up by a policeman and sent back to England by the local authorities. He has surely set up a record for the thousands of boys who dream of evading school.An ancient bus stopped by a dry river bed and a party of famous actors and actresses got off. Dressed in dark glasses and old clothes, they had taken special precautions so that no one should recognize them. But as they soon discovered, disguises can sometimes be too perfect.39。 said Gloria Gleam. It couldn39。 Brinksley Meers agreed. 39。t we e more often ?39。Meanwhile, two other actors, Rockwall Slinger and Merlin Greeves, had carried two large food baskets to a shady spot under some trees. When they had all made themselves fortable, a stranger appeared. He looked very angry. Now you gut out of here, all of you!39。 I39。t read !39。39。said Rockwall,39。t be too hard on us. I39。 Oh, is it ?39。Well, I39。 SOS 呼救信號(hào) lay thick on the ground. The woman knew that the nearest village was miles away. When it grew dark. she turned a suitcase into a bed and put the children inside it, covering them with all the clothes she could find. During the night, it got terribly cold. The woman kept as near as she could to the children and even tried to get into the case herself, but it was too small. Early ,next morning she heard planes passing overhead and wondered how she could send a signal. Then she had an idea. She stamped out the letters39。 in the snow. Fortunately, a pilot saw the signal and sent a message by radio to the nearest town. It was not long before a helicopter arrived on the scene to rescue the survivors of the plane crash.39。 said the voice of the television announcer,39。公司位于包拯的故鄉(xiāng)安徽省會(huì)合肥。公司創(chuàng)始人,榮獲國(guó)家三項(xiàng)技術(shù)專(zhuān)利的陳寶林先生,一直致力于生物質(zhì)能替代化石能源燃燒及污泥無(wú)害化處置與生物質(zhì)循環(huán)再利用方面的開(kāi)發(fā)與研究,三項(xiàng)技術(shù)專(zhuān)利號(hào)分別是:ZL2005 (送料鼓風(fēng)裝置)、(燃燒生物質(zhì)鍋爐送料、送風(fēng)噴口裝置)、(污泥生物質(zhì)焚燒系統(tǒng))。公司在鍋爐燃用生物質(zhì)能的技術(shù)改造工程中,在合肥地區(qū)、蚌埠市、全椒、和縣、六安市、涇縣、桐城,以及江蘇、廣西、湖北、黑龍江等地改燒了多臺(tái)4t/h至20t/h的鏈條爐排鍋爐和循環(huán)流化床鍋爐,以及寧國(guó)發(fā)電廠35t/h鏈條爐排電站鍋爐。 擬建地點(diǎn)本項(xiàng)目廠址選在安徽省宣城市涇縣烏溪鎮(zhèn)中國(guó)宣紙集團(tuán)公司工藝品廠對(duì)面,原中國(guó)宣紙集團(tuán)公司下屬原勞服公司,場(chǎng)地約500M2。 規(guī)模本項(xiàng)目為污泥(生物質(zhì))焚燒處置,其最終建設(shè)規(guī)模為:日污泥處置能力40噸。資金來(lái)源為:自籌50%,融資50%。如不進(jìn)行無(wú)害化處理,必將對(duì)周邊環(huán)境,及周邊人民的生產(chǎn)生活帶來(lái)巨大災(zāi)難,甚至影響到中國(guó)宣紙集團(tuán)公司的整體形象。因此,對(duì)污泥進(jìn)行無(wú)害化處置十分必要。3. 污泥處理處置概況 污泥的最終處置主要方法主要有:海洋投棄、土地利用、污泥農(nóng)用、填埋、焚燒以及綜合利用等。 污泥處置的趨勢(shì)從早期的海洋投棄與填埋,走向土地利用(綠地、林地利用)、農(nóng)用,發(fā)展到污泥的熱處理(熱干化與焚燒),最終會(huì)走向資源回收再利用的方向。隨著環(huán)境標(biāo)準(zhǔn)的逐次升級(jí),焚燒處理所占的的比例也越來(lái)越大。它可以使污泥中有機(jī)物全部碳化、燒死病原體,可以對(duì)含有重金屬或化學(xué)污染物的污泥實(shí)現(xiàn)完全的惰性化處理,可最大限度減少污染,且焚燒后產(chǎn)生的焚燒灰可以用做改良土壤、制作建材等。 污泥熱干化處理是污泥處理技術(shù)中一種先進(jìn)和科學(xué)的處理方法。經(jīng)過(guò)干化處理后的污泥體積可以減為原來(lái)的五分之一左右,產(chǎn)品穩(wěn)定,且無(wú)臭味、無(wú)病原體生物。污泥的單獨(dú)使用熱干化工藝來(lái)處理有以下優(yōu)點(diǎn):可以減少污泥的體積,從而減少了儲(chǔ)存、處置和運(yùn)輸費(fèi)用;干燥處理后的污泥產(chǎn)品既可以用做肥料和土壤改良劑也可以用做其他工業(yè)工藝過(guò)程中原料或燃料;干燥后污泥無(wú)塵、無(wú)味,整個(gè)系統(tǒng)運(yùn)行安全、高效,且與污泥焚燒相比其投資和運(yùn)行成本較低。5. 現(xiàn)有污泥處理技術(shù)中的主要問(wèn)題 主流技術(shù)污泥富含有害污染物,同時(shí)也含有一些有益成分,比如它本身含有化學(xué)能,干燥的污泥在燃燒時(shí)可放出大量的熱量;某些污泥富含有價(jià)值的有機(jī)組分或無(wú)機(jī)組分。在此基礎(chǔ)上,可進(jìn)一步將污泥處理后的產(chǎn)物資源化,如作為原料或燃料等使用。 現(xiàn)有的熱干化技術(shù)早在20世紀(jì)40年代,工業(yè)化國(guó)家就已經(jīng)用直接加熱鼓式干燥器來(lái)干燥污泥。 無(wú)論終端無(wú)害化處理意向是污泥作為燃料還是原料利用,污泥干化都是重要的第一步,所以污泥干化在整個(gè)污泥處置體系中處于核心地位。 干燥不同的污泥,對(duì)設(shè)備的要求也不盡相同,這是因?yàn)槲勰嘣诟稍镞^(guò)程中有一特殊的膠粘相階段(含水率為60%左右)。 ② 尾氣處理和臭味控制 污泥終端處理必須是環(huán)境安全的,不能產(chǎn)生二次污染。以熱風(fēng)為干燥劑直接干燥時(shí),由于熱風(fēng)的量很大,使得尾氣處理成本非常高,這一缺陷使人們一度將興趣轉(zhuǎn)到了間接加熱系統(tǒng)上,后來(lái)發(fā)展出來(lái)的轉(zhuǎn)鼓式直接加熱工藝采用了氣體循環(huán)回用的設(shè)計(jì),尾氣的量只有直接加熱系統(tǒng)的15%,相應(yīng)尾氣處理的負(fù)擔(dān)大幅度下降。 ③ 設(shè)備安全問(wèn)題 在干燥器里,起火或爆炸事故相當(dāng)頻繁,令污泥干燥設(shè)備的安全性能倍受置疑。必須控制的安全要素是:氧氣含量<12%;粉塵濃度<60 g/m3;顆粒溫度<110 ℃。特別要指出的是,控制顆粒溫度是通過(guò)降低干燥劑溫度而實(shí)現(xiàn)參數(shù)控制的,這樣產(chǎn)生兩個(gè)問(wèn)題:一是加大了干燥劑流量,使得干燥劑的輸送功耗以及尾氣處理量都大幅度增加,成本急劇上升;二是膠粘相階段停留時(shí)間延長(zhǎng),使得污泥粘結(jié)問(wèn)題難以處理,影響設(shè)備的運(yùn)行可靠性。 現(xiàn)有的直接焚燒技術(shù)污泥的含水量高,直接焚燒時(shí),污泥所含的化學(xué)能甚至不足以維持所含水分的蒸發(fā),所以對(duì)于高含水率的污泥,必須加入其它燃料,同時(shí)對(duì)燃燒室進(jìn)行特殊的絕熱設(shè)計(jì),才能保證足夠高的焚燒溫度。隨著環(huán)境標(biāo)準(zhǔn)趨于嚴(yán)苛,焚燒處理的成本也越來(lái)越高,實(shí)際上,焚燒處理的成本幾乎完全受排放標(biāo)準(zhǔn)的制約,幾個(gè)控制性指標(biāo)有: 二噁英問(wèn)題二噁英是一類(lèi)劇毒物質(zhì),其急性毒性相當(dāng)于氰化鉀的1000倍,大量的動(dòng)物實(shí)驗(yàn)表明很低濃度的二噁英類(lèi)就對(duì)動(dòng)物表現(xiàn)出致死效應(yīng)。醫(yī)療及工業(yè)固體廢棄物焚燒爐是主要的二噁英類(lèi)排放源,國(guó)外已經(jīng)發(fā)生過(guò)多起強(qiáng)制關(guān)閉焚燒爐的事件。要在常規(guī)焚燒爐系統(tǒng)中控制二噁英的排放,以下技術(shù)措施是必須的: b 使用技術(shù)成熟可靠的爐膛和爐排結(jié)構(gòu),使垃圾在焚燒爐中得以充分燃燒,以減少二噁英的濃度; d. 盡量縮短煙氣在處理和排放過(guò)程中處于300~700℃區(qū)域的時(shí)間,控制排煙溫度不超過(guò)200℃。 惡臭問(wèn)題嚴(yán)格控制整個(gè)濕污泥系統(tǒng)以及爐膛內(nèi)都處于可靠的負(fù)壓狀態(tài),以保證處理現(xiàn)場(chǎng)無(wú)惡臭外溢,這需要增加相應(yīng)的設(shè)備投資和精細(xì)的運(yùn)行管理;同時(shí)燃燒室內(nèi)必須維持高溫,爐膛出口煙氣溫度不低于850℃,以保證消除煙氣的惡臭。以上特征直接影響到處理方案的選擇。 直接摻燒:不可行濕污泥直接在燃煤鍋爐內(nèi)直接摻燒,具有成本最低的顯著優(yōu)勢(shì),但該技術(shù)路徑是不可行的,判斷的理由有很多,主要有兩條,一是污泥本身的發(fā)熱量不足以支持其水分的蒸發(fā),在小型工業(yè)鍋爐內(nèi)摻燒的結(jié)果必然造成著火困難、爐膛溫度顯著下降,嚴(yán)重影響鍋爐的正常運(yùn)行;二是直接摻燒無(wú)法解決鍋爐房惡臭、排煙惡臭、二噁英分解等最基本的問(wèn)題,除非在爐膛內(nèi)新增柴油燃燒器作為輔助熱源,但成本無(wú)法接受。 一體化焚燒系統(tǒng):經(jīng)濟(jì)性不合理 一體化污泥焚燒是成熟可靠的技術(shù),該系統(tǒng)包括簡(jiǎn)單熱干化和焚燒爐兩個(gè)硬件系統(tǒng),配以柴油燃燒器(尾氣的二次燃燒),可以達(dá)到污泥的徹底無(wú)害化。 流程設(shè)計(jì)說(shuō)明:以專(zhuān)利技術(shù)為基礎(chǔ)的流程設(shè)計(jì)我公司通過(guò)長(zhǎng)期的技術(shù)積累,形成了專(zhuān)利技術(shù):污泥生物質(zhì)焚燒系統(tǒng)(已授權(quán),專(zhuān)利號(hào):),以該專(zhuān)利技術(shù)為基礎(chǔ),結(jié)合項(xiàng)目的基礎(chǔ)數(shù)據(jù),設(shè)計(jì)的中水污泥處理流程如下圖:凝結(jié)水水蒸汽熱汽循環(huán)汽尾氣干顆粒濕顆粒污泥倉(cāng)干粉倉(cāng)混捏機(jī)造粒機(jī)熱干化爐污泥焚燒鍋爐換熱器流程說(shuō)明:污泥與干粉在混捏機(jī)中混合均勻,進(jìn)入造粒機(jī)中制出濕顆粒,再進(jìn)入熱干化爐完成干化,干化熱源為循環(huán)汽;循環(huán)汽由換熱器加熱,加熱熱源為來(lái)自污泥焚燒鍋爐的飽和蒸汽,其凝結(jié)水通過(guò)疏水閥回流到鍋爐房軟水箱;熱干化爐產(chǎn)生的大量水汽進(jìn)入循環(huán)汽中,循環(huán)汽設(shè)置一個(gè)乏氣排放支路,以維持循環(huán)汽的總量平衡。熱干化后的中水污泥顆粒的含水率低于20%,通過(guò)對(duì)中國(guó)宣紙集團(tuán)公司的提供的中水污泥樣品制取的含水率為20%的檢材的實(shí)驗(yàn)室觀察證實(shí),這種污泥可以在大氣環(huán)境中存放,3天內(nèi)不散發(fā)臭味。 技術(shù)特征 獨(dú)特的造粒技術(shù)利用廉價(jià)的生物質(zhì)粉末,充分利用污泥的生物特性和生物質(zhì)粉末的吸水性,直接混捏造粒,該成型技術(shù)工藝路線簡(jiǎn)潔,圓滿解決了污泥粘結(jié)問(wèn)題,所制顆粒具有良好的冷態(tài)強(qiáng)度。多余的干燥尾氣直接送入污泥焚燒鍋爐爐膛,有效解決了污泥的惡臭問(wèn)題。 節(jié)省化石能源利用生物質(zhì)焚燒污泥,并將爐膛火焰中