【正文】 Enzymic hydrolysis of steam exploded herbaceous agricultural waste(Brassica carinata) at different particule sizes在不同粒子大小情況下草本農(nóng)業(yè)廢棄物(蕓苔屬植物)的蒸汽爆炸酶水解Abstract摘要The objective of this work was to evaluate the effect of particle size on steamexplosion pretreatment of herbaceous lignocellulosicbiomass. Hemicellulose and cellulose recovery, and effectiveness of enzymic hydrolysis of the cellulosic residue is presented for steamexplosion pretreatment of an agriculture residue (Brassica carinata) using different particle sizes. The parameters tested were: particle size (2
5, 5
8 and 8
12 mm), temperature (190 and 210 8C), and residence time (4 and 8 min). The positional analysis of filtrate and water insoluble fibre after pretreatment and enzymic digestibility data are presented. Larger steamexploded particle (8
12 mm) results in higher cellulose and enzymic digestibilities. The use ofvery small particles in steam explosion would not be desirable in optimising the effectiveness of the process improving economy.這項工作的目的是評估效果的粒子大小對蒸汽爆破預(yù)處理木質(zhì)纖維素的草本生物量。半纖維素和纖維素的復(fù)蘇,和有效性的纖維素酶法水解的殘留提出了蒸汽爆破預(yù)處理的農(nóng)業(yè)殘留物(蕓苔屬植物carinata)使用不同的粒子大小。測試參數(shù)是:顆粒大小(25,58和812毫米)、溫度(190和2108c)和停留時間(4和8分鐘)。成分分析的水不溶性纖維的濾液和預(yù)處理和酶消化后提出了數(shù)據(jù)。較大的蒸汽爆炸粒子(812毫米)導(dǎo)致更高的纖維素和酶消化性。 使用非常小的粒子在蒸汽爆炸不會是可取的,在優(yōu)化的過程的有效性的改善經(jīng)濟。1. Introduction介紹Herbaceous agricultural residues represent a major source of lignocellulosic material with considerable potential for use in biomasstoethanol renewable energy schemes. It is estimated that about 100 million tons of these residues are annually generated in the EU[1]. Selected herbaceous crops includingBrassica carinata are currently under study as potential energy sources[2]. B. carinata represents a new source of non food raw materials either for biomass to be processed into energy or for products from the seed oil which could betransformed into liquid biofuels and highvalueadded derivatives. Because of the special characteristics of this species, its production may serve for the diversification of agricultural systems of cereals in the Mediterranean region of the EU. The creation of a new market is alsoforeseen in the southern European countries as a solution to a future shortage of feedstocks for biodiesel in this area. Moreover, the lignocellulosic residue generated in this crop could be also an interesting feedstock for ethanol production[3].草本農(nóng)業(yè)殘留物代表的主要來源與可觀的潛力木質(zhì)纖維材料使用在生物質(zhì)乙醇可再生能源計劃。據(jù)估計,大約1億噸的這些殘留物是在歐盟每年生成。選擇草本作物includingBrassica carinata正在研究潛在的能量來源。b . carinata代表一個新源的非食品原料或者生物質(zhì)是加工成能源或產(chǎn)品從籽油可以轉(zhuǎn)化為液體燃料和highvalueadded衍生品。由于這一物種的特殊特征,其生產(chǎn)可能為多樣化的農(nóng)業(yè)系統(tǒng)在地中海地區(qū)的谷物的歐盟。創(chuàng)建一個新的市場也預(yù)見在南部歐洲國家來解決未來生物柴油原料的短缺在這個地區(qū)。此外,木質(zhì)纖維素的殘渣產(chǎn)生在這種作物可能也是一個有趣的原料在乙醇生產(chǎn)。Although considerable progress has been made in technology for the conversion of lignocellulosic biomass into ethanol, substantial opportunities still exist to reduce production costs[4,5]. In this context, enzymic hydrolysis processes are advantageous because enzymes carinata catalyse only specific reactions, consequently there are no side reactions or byproducts and the hydrolysis can potentially be run with yields approaching 100% of theoretical [6]. Pretreatment is necessary to achieve reasonable rates and yields in the enzymic hydrolysis of biomass. To open up the lignocellulosic structure to wide microbial degradation, expensive energy demand ing pretreatment processes are required. In the pretreatment area, the reduction of power for milling is one of the technological improvements that will result in substantially lower ethanol production costs. Autohydrolysis steam explosion has generally been accepted as one of the most costeffective method for pretreating lignocellulosic biomass, since no addition of external catalyst is necessary[7
9].The most important variables in steamexplosion pretreatment are time, temperature and chip size. Generally, when larger chips are used, heat transfer problems may res