發(fā)泡聚苯乙烯的回收
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1、 塑料成型工藝 -------發(fā)泡聚苯乙烯(EPS)的回收 學(xué)號(hào): 姓名: 楊勇 成績(jī): 2012年4月 摘要:發(fā)泡聚苯乙烯又名聚苯乙烯泡沫, 也叫泡沫塑料, 簡(jiǎn)稱EPS , 它是由聚苯乙烯、阻燃劑和發(fā)泡劑組成, 是一種用途廣泛的新型材料, 主要用于包裝、保溫領(lǐng)域, 在家用電器、儀器、儀表
2、、工藝品及其它易損貴重產(chǎn)品的包裝及近年來(lái)迅速發(fā)展的快餐食品包裝中應(yīng)用較廣。但由于產(chǎn)品為一次性使用, 用后若隨意丟棄, 容易造成環(huán)境污染, 而且在水中或泥土中多年不腐爛, 影響市容及農(nóng)作物的生產(chǎn) ;若集中堆放, 占地面積大, 不利于防火; 若將其當(dāng)作廢料燃燒, 會(huì)產(chǎn)生一種刺鼻的黑煙, 對(duì)環(huán)境造成嚴(yán)重危害。本文旨在講述回收廢EPS的科學(xué)方法、技術(shù)與應(yīng)用,提高聚苯乙烯的回收利用價(jià)值,保護(hù)環(huán)境。 關(guān)鍵詞:發(fā)泡聚苯乙烯 回收 新型材料 環(huán)境污染 利用價(jià)值 發(fā)泡聚苯乙烯(EPS)的回收 發(fā)泡聚苯乙烯又名聚苯乙烯泡沫, 也叫泡沫塑料, 簡(jiǎn)稱EPS , 它是由
3、聚苯乙烯、阻燃劑和發(fā)泡劑組成, 是一種用途廣泛的新型材料, 主要用于包裝、保溫領(lǐng)域, 在家用電器、儀器、儀表、工藝品及其它易損貴重產(chǎn)品的包裝及近年來(lái)迅速發(fā)展的快餐食品包裝中應(yīng)用較廣。大家所熟知的模塑包裝泡沫、建筑絕緣材料、盛蔬菜和魚的板條箱、公共餐飲業(yè)和快餐店的盤子和飯盒等,都是由EPS 制成 。但由于產(chǎn)品為一次性使用, 用后若隨意丟棄, 容易造成環(huán)境污染, 而且在水中或泥土中多年不腐爛, 影響市容及農(nóng)作物的生產(chǎn) ;若集中堆放, 占地面積大, 不利于防火; 若將其當(dāng)作廢料燃燒, 會(huì)產(chǎn)生一種刺鼻的黑煙, 對(duì)環(huán)境造成嚴(yán)重危害。 具有諷刺意義的是,EPS的一些有價(jià)值的特性阻礙了對(duì)它的廣泛回收。它的
4、質(zhì)量較輕意味著在定點(diǎn)可回收的材料量非常有限,如快餐店或?qū)W校餐廳每星期平均產(chǎn)生的廢EPS包裝材料量只有45kg。這個(gè)量很難保證相關(guān)的運(yùn)輸成本和隨后的機(jī)械回收費(fèi)用。而且,EPS用語(yǔ)各種形式的產(chǎn)品,使消費(fèi)者很難辨認(rèn)。 那么,發(fā)泡聚苯乙烯該如何回收呢? 日本從七十年代開始首先進(jìn)行對(duì)EPS廢料工業(yè)化處理和利用的研究, 隨著塑料工業(yè)的迅速發(fā)展,EPS塑料的產(chǎn)量日益增加, 僅我國(guó)年產(chǎn)量就在約十萬(wàn)噸以上, 因此對(duì)廢EPS塑料的回收利用已引起人們的足夠重視, 并先后在不同領(lǐng)域內(nèi)開展研究工作,先后取得了不錯(cuò)的進(jìn)展。 (一)、EPS的回收技術(shù)手段 為了給大家更好的理解廢EPS塑料的回收利用,我們先來(lái)介紹一下
5、在回收過(guò)程中常用的技術(shù)手段。 1、 EPS泡沫的壓實(shí) 大多數(shù)EPS回收過(guò)程中的一個(gè)重要部分是泡沫的壓實(shí),以便它能夠方便地運(yùn)輸、計(jì)量和搬運(yùn)。EPS泡沫的壓實(shí)涉及到泡孔結(jié)構(gòu)的完全或部分坍塌。為了使容積密度增加,排除泡孔中的空氣是必要的?,F(xiàn)在很多公司設(shè)計(jì)開發(fā)了一系列專門用于EPS等松散物料壓實(shí)的設(shè)備。這種EPS壓實(shí)機(jī)可以大大減少EPS泡沫的占用空間,方便EPS泡沫塊的回收和運(yùn)輸。應(yīng)用這種泡沫壓實(shí)機(jī),把EPS泡沫材料壓縮成密度比較大的塊狀,可以大大降低運(yùn)輸成本,方便進(jìn)一步再生處理或占用較少的垃圾填埋空間。 2. 廢EPS的粉碎 EPS的回收最簡(jiǎn)單的方法是泡沫的粉碎。來(lái)源
6、于廢棄包裝材料的EPS可被粉碎用來(lái)生產(chǎn)分級(jí)的EPS泡沫碎片。制得的EPS泡沫碎片粒徑為1—50mm,這取決于旋轉(zhuǎn)切斷機(jī)的類型。生產(chǎn)不同的粒徑等級(jí)以適用于特定的場(chǎng)合。廢EPS泡沫經(jīng)過(guò)適當(dāng)粉碎可作為土壤改良劑(粒徑范圍為4—8mm)、堆肥助劑(粒徑范圍為6—12mm)、也可用作田地排水系統(tǒng)(粒徑范圍為8—25mm)和排水管覆蓋層(粒徑范圍為25—50mm). (二)、EPS的回收形式 1、 EPS的機(jī)械回收 聚苯乙烯泡沫塑料是熱塑性塑料,回收的EPS將會(huì)重新制成聚苯乙烯. 民用EPS泡沫通常以袋裝形式用半掛拖車運(yùn)送到機(jī)械回收廠。一旦檢查完卸下的廢EPS后,就通過(guò)手工分離除去
7、雜質(zhì),如紙、金屬、其他的聚合物和食品殘?jiān)H缓髮⒕酆衔锓鬯槌山q狀物,隨后進(jìn)入洗滌和干燥過(guò)程。絨狀物首先通過(guò)離心干燥出去大量的水,再通過(guò)對(duì)流加熱干燥。接著采用擠出機(jī)壓縮并將絨狀物加熱到205℃,最后通過(guò)帶花邊的口模擠出并制粒. 制粒是指用EPS壓縮機(jī)和回收造粒機(jī)將EPS廢料轉(zhuǎn)化為PS顆粒,用于制造塑料制品,如衣架、花盆、錄影帶、家具、建筑材料或保溫材料等。無(wú)論是哪種方式,回收EPS前提都需要進(jìn)行壓縮,才能降低整個(gè)回收流程的成本。 ★ 機(jī)械回收EPS過(guò)程中的降解: 在EPS的機(jī)械回收過(guò)程中,由于壓實(shí)過(guò)程中的局部過(guò)熱或者再次配合導(dǎo)致的熱歷史會(huì)使聚合物發(fā)生部分降解。這種降解可由顏色
8、變黃和產(chǎn)生氣味(由于乙醛降解產(chǎn)物的生產(chǎn))而證實(shí)。變色是阻燃劑改性的EPS所特有的問(wèn)題,由于這些添加劑是溫度敏感型的,能在聚合物再加工過(guò)程中分解。值得注意的是,由于民用EPS已應(yīng)用食品行業(yè),因此,不好的氣味也可能是食品殘?jiān)坝椭蛘呤秤糜蜌堄辔锏拇嬖趯?dǎo)致的。 用于EPS中的添加劑在機(jī)械回收過(guò)程中也會(huì)出現(xiàn)降解和腐蝕問(wèn)題。例如,在EPS的回收過(guò)程中含鹵阻燃劑會(huì)形成鹵化氣體,在水存在的情況下這些氣體會(huì)形成酸,從而導(dǎo)致加工設(shè)備的腐蝕。此外,EPS的分子量會(huì)下降并最終影響到材料的機(jī)械性能, 潤(rùn)滑劑如金屬的硬脂酸鹽也會(huì)與阻燃劑和成核劑反應(yīng)而使泡孔結(jié)構(gòu)失控。 2、EPS的溶劑回收 一種比較新的回
9、收EPS的方法是將EPS聚合物溶解在檸檬油精中。檸檬油精是從柑橘類水果皮中提取的可生物降解的溶劑(即橘皮黃酮)。當(dāng)這種溶劑噴到EPS泡沫上時(shí),EPS泡沫放出氣體,并轉(zhuǎn)化成密度比原始發(fā)泡材料 高很多倍的凝膠狀材料。d-檸檬油精這種溶劑能夠安全地溶解EPS并且?guī)缀醪挥绊懢酆衔锏氖褂眯阅?。d-檸檬油精的結(jié)構(gòu)和性能如圖所示: 分子式 C10H16 分子量 136.24 結(jié)構(gòu)式 相對(duì)密度(20℃) 0.844 粘度(25℃)/mPa.s 0.98 凝固點(diǎn) -97℃ 沸點(diǎn) 175.~179℃ 折光率 1.473 閃點(diǎn) 4
10、8℃ 自燃點(diǎn) 237℃ 無(wú)色液體。易燃。有刺激性。有愉快的檸檬香味。能與乙醇混溶,不溶于水 。 由于它能通過(guò)卡車大量運(yùn)送到塑料回收廠中,因此使用這種溶劑能夠顯著地提高運(yùn)輸廢EPS泡沫的經(jīng)濟(jì)效果。通過(guò)網(wǎng)式過(guò)濾器過(guò)濾凝膠來(lái)純化廢PS,不僅能夠出去粒子狀的雜質(zhì)如土,也能夠除去其他的聚合物,這是由于這些物質(zhì)不溶于檸檬油精。凝膠過(guò)濾后,通過(guò)將第二種溶劑(嚴(yán)格來(lái)說(shuō)是非溶劑)加到混合物中使純化的PS沉淀。最后采用離心分離將這3種組分分離,使PS脫氣并擠出,溶劑蒸發(fā)并回收重復(fù)使用。 用于EPS回收的d-檸檬油精工藝有下列優(yōu)點(diǎn): ① 作為天然的溶劑,d-檸檬油精是絕對(duì)安全的
11、,是無(wú)毒的; ② 由于在溶解和壓實(shí)過(guò)程中不加熱,因此聚苯乙烯的物理性能幾乎沒(méi)有下降; ③ EPS的體積降為原始體積的1/25,這大大節(jié)約了運(yùn)輸成本; ④ d-檸檬油精可以回收并反復(fù)使用多次; ⑤ 由于只將EPS浸泡在d-檸檬油精中而使其溶解,因此加工過(guò)程中幾乎不需要能量; ⑥ 值得注意的是,盡管d-檸檬油精是有機(jī)精制油,但從阻燃角度來(lái)說(shuō)它是安全的。實(shí)驗(yàn)證明,將點(diǎn)煙的香煙扔進(jìn)含有20%EPS溶解物的檸檬油精溶液中,溶液不會(huì)燃燒。 3、EPS的焚燒,回收能量 當(dāng)大量的EPS機(jī)械回收不能產(chǎn)生可觀的經(jīng)濟(jì)效益時(shí),焚燒EPS廢物并回收能量是可行的方法。廢焚燒法回收熱能是將廢棄聚苯乙烯塑料置于
12、特殊的焚燒爐中燃燒回收熱量,以替代部分燃料。聚苯乙烯的熱值高達(dá)4600kJ/kg,超過(guò)了燃油平均4400kJ/kg的熱值,換句話說(shuō),1kgEPS泡沫產(chǎn)生的熱量等于1.2—1.4L燃料油產(chǎn)生的熱量,從而可部分替代煉鐵、發(fā)電、燃燒鍋爐的燃料。燃燒法雖然可以獲得能量但需要使用專門的燃燒高爐,否則聚苯乙烯燃燒不充分會(huì)產(chǎn)生苯乙烯、二惡英等有害物質(zhì),對(duì)環(huán)境造成二次污染。焚燒法回收裝置成本較高,而且材料的使用價(jià)值也沒(méi)有得到充分的利用。 (三)、回收EPS的應(yīng)用 1、用于制造輕質(zhì)建筑材料:用可發(fā)性聚苯乙烯的預(yù)發(fā)泡顆粒或以破碎成小塊的聚苯乙烯泡沫廢棄物為主體補(bǔ)加不同的填料,使用不同的粘結(jié)劑制成各種輕
13、質(zhì)的建筑材料。比如,用碎木絲為填料,以水泥為粘結(jié)劑,加水混合,然后模塑成各種形狀的輕質(zhì)水泥隔板,或制成人造木材;內(nèi)襯鐵絲支架制成的輕質(zhì)泡沫板可以作為墻板、臺(tái)面,或裝飾板;用膨脹珍珠巖做填料能制成屋頂隔熱板;以泥土為粘接劑和填料,與聚苯乙烯泡沫顆粒等量均勻混合并壓制成型,干燥后煅燒,可制成供高層建筑用的輕質(zhì)大砌塊,或地下滲、排廢水的透水管;以廢尼龍絲為填料可制成輕質(zhì)抗彎澆鑄材料等等。這種回收方法工藝簡(jiǎn)單,可回收量大,投資小,是一種較好的回收利用方式,唯一不足就是產(chǎn)品的技術(shù)附加值較小。 2、用于制造通用型聚苯乙烯:將聚苯乙烯泡沫廢棄物經(jīng)高溫消泡冷卻后,機(jī)械破碎,擠塑成條,再切粒制成通用型聚苯
14、乙烯。這種方法的主要問(wèn)題是再生料的外觀可能是由于廢棄泡沫破碎前未洗凈以及在烘焙擠塑過(guò)程中局部溫度過(guò)高等原因而呈棕色,失去了新聚苯乙烯無(wú)色透明的特點(diǎn)。其抗沖擊性能也較差,只能用做一些低值塑料零件,很難與一般塑料如聚乙烯、聚丙烯、聚氯乙烯制品媲美。 3、用于再制可發(fā)性聚苯乙烯:用廢棄PS泡沫循環(huán)再制EPS或再模制泡沫制品,應(yīng)該說(shuō)是廢PS泡沫最合理的利用方向。因?yàn)閺U聚苯乙烯泡沫材料除表面受環(huán)境污染略變質(zhì)外,內(nèi)部還保持著原有聚苯乙烯泡沫的性能,這就為多次利用創(chuàng)造了條件。只有這樣,重新模塑或制造EPS才能最好地發(fā)揮聚苯乙烯泡沫的多方面優(yōu)良特性。利用廢聚苯乙烯泡沫制造EPS或再模塑有下列幾種方法:第
15、一,溶解聚合法。將廢烙泡沫材料溶解于苯乙烯單體中,加入分散劑使PS的苯乙烯溶液成珠粒狀懸浮在水中,加熱使其聚合,然后加發(fā)泡劑,繼續(xù)聚合制成珠粒發(fā)泡料。它的優(yōu)點(diǎn)是利用廢烙代替了部分苯乙烯,可使成本降低,缺點(diǎn)是要消耗苯乙烯單體,同時(shí)也受到PS表面清潔度不穩(wěn)定對(duì)引發(fā)劑活性的影響,很難制得均勻一致的產(chǎn)品。第二,球化發(fā)泡法。是將通用型的聚苯乙烯切成圓柱形粒料,懸浮在分散劑的水溶液中,加熱使圓柱體熔融球化,再降溫加壓加發(fā)泡劑,冷卻后經(jīng)過(guò)濾、洗滌和低溫干燥制成珠粒本方法的關(guān)鍵在于原料的質(zhì)量,否則難以保證新制EPS的質(zhì)量。第三,珠粒破碎再模塑法。是在液體介質(zhì)中選用合適的軟化劑,表面活性劑和消泡劑,將大塊廢PS
16、泡沫選擇性地破碎到直徑4—8mm的球形珠粒,加發(fā)泡劑后再模塑成泡沫制品。本法工藝簡(jiǎn)單,消耗的附加材料少,模制成品的各項(xiàng)物理性能與原廢料接近,而且投資小,效益大,值得推廣。 4、溴化改性制備阻燃劑。聚苯乙烯分子中含有苯環(huán)結(jié)構(gòu),苯環(huán)上的氫原子可被親電試劑取代。有人將回收的聚苯乙烯泡沫塑料清洗干燥后溶于二氯甲烷溶液中,在三氯化鋁催化下,與液溴發(fā)生親電取代反應(yīng)而制得阻燃劑溴化聚苯乙烯。含溴量可高達(dá)6%,可作為聚氯乙烯、ABS、聚丙烯等塑料制品的阻燃。與其它有機(jī)阻燃劑相比,溴化聚苯乙烯用量低,阻燃效果好,燃燒過(guò)程中不釋放惡英等有毒致癌物質(zhì),特別是與三氧化二銻并用,其協(xié)同阻燃效果更好,是一種性能良好
17、的阻燃劑。用該工藝制備的溴化聚苯乙烯,性能可以與商品溴化聚苯乙烯阻燃劑相媲美,而且成本低。但因?yàn)樽枞紕┍旧淼挠昧烤筒皇呛艽?,因此此法不能滿足大量廢PS的回收工作。 5、熱分解技術(shù):一方面,可裂解制造苯乙烯單體,即把廢聚苯乙烯泡沫塑料在加熱條件下,選擇合適的催化劑使其裂解生成苯乙烯單體。在苯乙烯供應(yīng)比較緊張的情況下,利用聚苯乙烯泡沫廢棄物解聚制造苯乙烯,以滿足市場(chǎng)的需要,是一條合理的利用途徑。美國(guó)、法國(guó)、和日本等也進(jìn)行過(guò)大量實(shí)驗(yàn),但未見有工業(yè)化的報(bào)導(dǎo)。解聚制造苯乙烯主要問(wèn)題是苯乙烯的轉(zhuǎn)化率比較低,在較好的情況下也不過(guò)70%左右,一般僅在40%左右,轉(zhuǎn)化率低,不僅影響生產(chǎn)成本,而且留下的殘?jiān)?/p>
18、還給裂解設(shè)備的清洗和連續(xù)運(yùn)轉(zhuǎn)造成困難。另一方面,可裂解制油。將泡沫塑料隔絕空氣加熱或在水汽下加熱分解可得到小分子量烴的混合物,再用催化劑分解重整,可得不含硫的汽油餾份和煤油餾份及部分氣體。1kg塑料可得1L油品,其余主要是殘?zhí)?。日本在這方面研究較多,我國(guó)在這方面也取得一定成效,現(xiàn)在正在進(jìn)行產(chǎn)業(yè)化。 6、接枝改性制備涂料。涂料的制備均由基料添加顏料經(jīng)攪拌研磨而成?;蠟槌赡の?,聚苯乙烯泡沫由有機(jī)高分子組成,經(jīng)溶劑溶解以后可以作為涂料的基料,其耐水性和絕緣性良好。但用作基料制備的涂料附著力和成膜性很差,只要將其進(jìn)行改性處理并添加適量的交聯(lián)劑,增塑劑,以改善其成膜性能及膜層質(zhì)量,這樣就可以制成
19、各類涂料。比如,將廢聚苯乙烯泡沫塑料粉碎后溶于二甲苯中,加入引發(fā)劑,在一定溫度下滴入丙烯酸進(jìn)行接枝改性反應(yīng),得組份甲;將石油瀝青溶于二甲苯,得組份乙;將水、乳化劑以及助劑混合均勻得組份丙;將上述三種成份在乳化釜中進(jìn)行共乳化,制得防水涂料。丙烯酸分子在聚苯乙烯的分子鏈上的接枝,不僅增強(qiáng)了涂膜的附著力,而且提高了乳液的穩(wěn)定性。制得的涂料具有良好的耐熱性、低溫柔韌性和粘接強(qiáng)度。另外,用柔性的丙稀酸丁酯接枝在剛性的聚苯乙烯分子鏈上,可提高聚苯乙烯的柔韌性和附著力,與適當(dāng)助劑配合,可制成性能良好的防腐涂料。 參考文獻(xiàn): 1、【澳】約翰.沙伊斯 著 《聚合物回收---科學(xué)、技術(shù)與應(yīng)用》
20、 化學(xué)工業(yè)出版社 2004.4 2、鐘世云 許乾慰 王公善 編著 《聚合物降解與穩(wěn)定化》 化學(xué)工業(yè)出版社 2002.12 3、韓寶仁 朱元吉 馮連勛 編著 《塑料異型材制造原理與技術(shù)》 化學(xué)工業(yè)出版社 2001.9 4、王建國(guó) 編著 《高分子合成新技術(shù)》 化學(xué)工業(yè)出版社 2004.4 5、翟金平 胡漢杰 主編 《聚合物成型原理及成型技術(shù)》 化學(xué)工業(yè)出版社 2001.7 附:英文文獻(xiàn) (一)、Mechanical recycling EPS in the process of degradation ----By J
21、ohn. Shayi Si Expanded polystyrene, also known as polystyrene foam, also known as foam, referred to the EPS, it is made ??of polystyrene, flame retardants and blowing agents, is a versatile new materials, mainly used for packaging,insulation field, a wider application in the packaging of household
22、appliances, instruments, meters, crafts and other vulnerable valuable products and the rapid development in recent years, fast food packaging. Molded packing foam, known as building insulation materials, crates of of Sheng vegetables and fish, public catering and fast food shops, plates and lunch bo
23、xes are made ??from EPS. However, due to a one-time use product, used, thrown away, likely to cause environmental pollution, and not rot in the water or soil for many years, affecting the amenity and crop production; if the focus is stacked large area, is not conducive to the fire; if as waste combu
24、stion, will produce a pungent black smoke, causing serious harm to the environment. Ironically, some of the valuable features of the EPS hindered its wide range of recycling. The quality of lesser means are very limited in the amount of designated recyclable materials, such as fast food restaurants
25、 or school cafeterias week on average generated waste EPS packaging material is only 45kg. This quantity is difficult to ensure that the transportation costs and the subsequent mechanical recycling cost. Moreover, the EPS terms of products of various forms, so that consumers difficult to identify.
26、Because a lot of transporting it by truck to a plastic recycling factory, so the use of such solvents can significantly improve the economic effects of the transport of waste EPS foam. By comb filters gel purification of waste PS, not only to go out to the particle-like impurities such as soil, can
27、also remove the other polymers, it is because these substances do not dissolve in the limonene. Gel filtration, the solvent will be the second (strictly speaking, non-solvent) is added to the mixture manipulation precipitation of purified PS. Finally, the centrifugal separation of these three kinds
28、of component separation, the PS degassing and extrusion, solvent evaporation and recycled to be reused. EPS mechanical recycling process due to local overheating in the compaction process again with the result of the thermal history makes polymer partially degraded. This degradation is confirme
29、d by the yellow color, and odor (due to the acetaldehyde degradation products in production). The color is flame retardant modified EPS-specific problems, because these additives are temperature sensitive, can decompose in the polymer processing. It is worth noting that the civil EPS has been applie
30、d to the food industry, an unpleasant smell may also be caused by the presence of food residues and grease or cooking oil residue of. Additives used in the EPS will also appear in the mechanical recycling process degradation and corrosion problems. For example, the halogen-containing flame retardan
31、ts in EPS recycling process the formation of halogenated gases, these gases in the presence of water the formation of acid, leading to corrosion of processing equipment. In addition, the molecular weight of EPS will decline and ultimately affect the mechanical properties of materials, lubricants suc
32、h as metal stearate will be flame retardant, and nucleating agent response, leaving the foam structure out of control. A relatively new method of recycling EPS polymer dissolved in limonene. Limonene is a biodegradable solvent extracted from citrus fruit peel (orange peel flavonoids). When the solv
33、ent is sprayed into the EPS foam, EPS foam emits gases, and transformed into a density many times higher than the original foam material of the gelatinous material. D-Limonene such solvents can be safely dissolved EPS and almost does not affect the use properties of the polymer. D-Limonene proces
34、s for EPS recycling has the following advantages: As a natural solvent d-Limonene is absolutely safe, non-toxic; As the heat in the process of dissolution and compaction, so the physical properties of polystyrene almost did not decline; EPS volume reduced to the original volume of 1/25, a signi
35、ficant reduction in transportation costs; d-Limonene can be recycled and used for several times; As an EPS soaked in d-Limonene to dissolve, so the process requires little energy; It is noteworthy that, although the d-Limonene is organic refined oil, but the flame-retardant point of view it is s
36、afe. Experiments show that the cigarette lighter cigarette thrown into the Limonene solution containing 20% EPS solutes, the solution will not burn. (二)、Recycling Mystery: Expanded Polystyrene ——By Kasen Seaver It’s the eternal question: Can I recycle expande
37、d polystyrene? It’s everywhere: It holds your food, secures items in packages, provides insulation in homes and it’s even in your bike helmet. It’s also known as plastic #6, which you’ve seen used in plastic cups and CD and DVD cases. Fun fact: In 2006, the Alliance of Foam Packaging Recyclers rep
38、orted that 56 million pounds of EPS were recycled that year alone. That’s an astonishing amount considering that EPS is 98 percent air. Here’s the thing: Even if your community recycles plastic #6, it may not accept EPS. It’s a similar case to the plastic bag conundrum, where different versions of
39、plastics require separate recycling streams. Because it’s so lightweight, EPS takes up 0.01 percent of the total municipal solid waste stream by weight, but as you may have guessed, its volume is a greater problem than its weight. It takes up space in landfills and doesn’t biodegrade. If you haven’
40、t recycled EPS before, here’s how: Methods of Recycling Like we mentioned earlier, the most convenient method for consumers utilizes curbside recycling programs; however, due to transportation coordination and contamination rates, most communities do not have EPS recycling programs. But don’t de
41、spair; you have a number of options at your fingertips: Drop-off sites – Check E to find where you can find polystyrene recycling in your area. Make sure to call local sites beforehand to make sure EPS is accepted and in what form. If they do take EPS, most accept packing materials but not food or
42、medical containers. Bring empty containers free of tape, labels, plastic film, etc. As you know, contaminants can ruin the recycling process. Mail-back - If a drop-off site doesn’t exist in your area, you can also use a mail-back program such as the Alliance of Foam Packaging Recyclers. Remember t
43、o remove all debris from the EPS before breaking it into smaller pieces that fit into a box for shipping. Reuse for loose fill – What about packing peanuts? Their simplest reuse is in another package you need to ship. You can also donate them to UPS or other shipping stores, who will gladly reuse
44、the material. Not sure where to go? Call the automated, 24-hour Peanut Hot line at 800-828-2214 to find a site near your residence that will reuse them. Large volume - Working with a recycling company for pick-up service is best if your business receives mass amounts of EPS. Company requirements f
45、or storage and equipment vary, but it’s typical for storage containers to remain outdoors in a bin where EPS is kept clean, dry and unexposed to the elements. It is wise to check with the company to see how they accept EPS, whether it be stacked, bagged, bailed, condensed, etc. On-site (for industr
46、y) – In the event that your business needs to routinely condense large pieces of EPS, look for devices from companies like RecycleTech or Styromelt?. For example, Styromelt? is a device that uses thermal compaction to not only reduce the volume of EPS, but also to sterilize the briquette. Adva
47、ncing Technologies Biodegradable packing materials are definitely in style. Puffy Stuff produces a plant-based product that can be used as fertilizer on your lawn. It breaks down into inert proteins after coming in contact with water and is consumed by soil bacteria. Puffy Stuff claims its product
48、is so natural, you can eat it (although we haven’t tried it – yet!). Also, scientists at Sony discovered that EPS completely dissolves when sprayed with limonene, a natural oil extracted from the skin of oranges or other citrus fruits. The EPS dissolves at room temperature and can be processed for reuse. Because of the varied uses for EPS, recycling requirements are a little more complex than, say, paper and other plastics, but it is worth taking the time in order to keep this prevalent material in use and out of landfills.
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