成型和灼烧温度对垃圾衍生燃料灰渣理化特性的影响

以生活垃圾衍生燃料(refuse derived fuel,RDF)为研究对象,通过挤压成型的RDF与非成型的RDF在600~1 100℃条件下灼烧,所产生的灰渣进行质量、粒径、化学成分等特性进行分析,探索RDF灰渣随温度变化的规律以及潜在的应用价值。研究结果表明,在1 000℃以下,RDF灰渣随着温度提高,灰分组分发生分解反应,主要是残余有机物、碳酸盐、硫酸盐的分解,灰渣粒径减小;当温度升至1 000℃以上,灰分组分发生化合反应,生成产物以复合硅酸盐为主,灰渣粒径增大甚至结块;灰渣在化学反应过程中,非金属元素C,Cl,S转化为气体化合物逸出主体,使灰渣质量减小;成型RDF灰渣晶体含量比非成型RDF高;成型RDF灰渣粒径比非成型RDF灰渣大。     

生物质飞灰对餐厨垃圾两相厌氧消化的影响

为解决餐厨垃圾在厌氧消化过程中的酸抑制问题,并为生物质飞灰提供新的资源化利用途径,在产酸相中添加不同比例的飞灰,研究了生物质飞灰对餐厨垃圾中温两相厌氧消化过程中产酸和产气的影响。结果表明:添加生物质飞灰可以提高酸化相的p H值,促进餐厨垃圾酸化,添加3%的生物质飞灰,产酸相的挥发性脂肪酸(VFA)的平均浓度为9 845.45 mg·L-1,比空白处理(CK)提高了49.66%,差异显著;添加3%生物质飞灰处理的产甲烷相更稳定,产气效果更好,累积产气量为27.43 L,比0、1%、4%和5%的飞灰添加比例分别高了25.15%、13.70%、4.34%和6.55%;添加3%生物质飞灰处理的平均负荷产气量为490.33 m L·g VS-1,比0、1%、4%和5%的飞灰添加比例平均值分别提高了22.49%、12.35%、6.36%和8.22%。研究表明,添加生物质飞灰有助于促进餐厨垃圾酸化和提高产甲烷相的产气量;在高有机负荷的时候,添加生物质飞灰有助于提高系统运行的稳定性。     

绒毛白蜡根区局部盐胁迫对其生长的影响

绒毛白蜡（Fraxinus velutina）是滨海盐渍区主要的植被和园林绿化乔木,其发达的根系易受土壤盐分异质性的影响。为探索局部盐胁迫对其生长的影响,采用分根培养桶对幼苗进行局部盐胁迫处理,分析幼苗的生长特征、光合特性、根系分布和离子积累。结果表明,局部低盐胁迫处理的幼苗生长量显著高于均匀盐胁迫和局部高盐胁迫处理;虽然局部高盐胁迫对叶片的水势无影响,但是显著降低了叶片的气孔导度、光合速率和蒸腾速率。局部盐胁迫处理中,无盐胁迫区的根系生物量显著高于盐胁迫区;与均匀盐胁迫相比,局部盐胁迫能够显著降低叶片中Na+的含量,增加K+/Na+。虽然绒毛白蜡的生长在局部盐胁迫条件下受到抑制,且局部盐分越高抑制越强,但生长量与均匀盐胁迫相比显著增高。在局部盐胁迫条件下,细根在无胁迫区的补偿性生长能够提供叶片所需水分,降低叶片中Na+的积累,增加K+含量,缓解了盐胁迫的不利影响。     

西伯利亚花楸组培苗增殖扩繁培养

该试验采用不同的培养基配方针对西伯利亚花楸组培苗进行扩大培养,以得出最佳扩 繁培养基配方,结果表明:MS+6-BA 0.5 mg/L+NAA 0.12 mg/L+IBA 0.05 mg/L+GA3 1.0mg/L 配方最有利于西伯利亚花楸组培苗的扩繁。     

赤泥与粉煤灰固稳疏浚底泥磷的研究

底泥疏浚是解决水体富营养化的重要举措之一,如何有效处理疏浚底泥已经成为亟待解决的难题。土地利用是有效吸纳疏浚底泥的方法之一,但却存在营养元素尤其是磷元素容易流失的问题。以铝业矿渣赤泥和煤燃烧副产物粉煤灰为原料,将其用于疏浚底泥中磷的固稳,考察了疏浚底泥的性质、固稳剂对疏浚底泥pH的影响、固稳时间以及固稳剂添加量对磷浸出量的影响。结果表明:疏浚底泥的pH随着固稳剂添加量的增加而升高,磷的浸出量随着固稳时间的延长而降低;对于掺混赤泥的疏浚底泥,磷的浸出量随着赤泥添加量的增加而增加,而对于掺混粉煤灰或赤泥与粉煤灰等量混合的疏浚底泥,磷的浸出量随着固稳剂添加量的增加而降低。粉煤灰或赤泥与粉煤灰等量混合作为固稳剂均能够有效固稳疏浚底泥中的磷。     

Growth,Metabolism and Yield of Rice Cultivated in Soils Amended with Fly Ash and Cyanobacteria and Metal Loads in Plant Parts

Soil amendment with fly ash(FA) and combined supplementation with N_2-fixing cyanobacteria masses as biofertilizer were done in field experiments with rice. Amendments with FA levels, 0, 0.5, 1.0, 2.0, 4.0, 8.0 and 10.0 kg/m~2, caused increase in growth and yield of rice up to 8.0 kg/m~2, monitored with several parameters. Pigment contents and enzyme activities of leaves were enhanced by FA, with the maximum level of FA at 10.0 kg/m~2. Protein content of rice seeds was the highest in plants grown at FA level 4.0 kg/m~2. Basic soil properties, p H value, percentage of silt, percentage of clay, water-holding capacity, electrical conductivity, cation exchange capacity, and organic carbon content increased due to the FA amendment. Parallel supplementation of FA amended plots with 1.0 kg/m~2 N_2-fixing cyanobacteria mass caused further significant increments of the most soil properties, and rice growth and yield parameters. 1000-grain weight of rice plants grown at FA level 4.0 kg/m~2 along with cyanobacteria supplementation was the maximum. Cyanobacteria supplementation caused increase of important basic properties of soil including the total N-content. Estimations of elemental content in soils and plant parts(root and seed) were done by the atomic absorption spectrophotometry. Accumulations of K, P, Fe and several plant micronutrients(Mn, Ni, Co, Zn and Cu) and toxic elements(Pb, Cr and Cd) increased in soils and plant parts as a function of the FA gradation, but Na content remained almost unchanged in soils and seeds. Supplementation of cyanobacteria had ameliorating effect on toxic metal contents of soils and plant parts. The FA level 4.0 kg/m~2, with 1.0 kg/m~2 cyanobacteria mass supplementation, could be taken ideal, since there would be recharging of the soil with essential micronutrients as well as toxic chemicals in comparative lesser proportions, and cyanobacteria mass would cause lessening toxic metal loads with usual N_2-fixation.     

Ca/CTS/FA复合材料对酸性大红的吸附研究

以粉煤灰(Fly ash,FA)为原料,通过负载壳聚糖和钙离子制备一种新型吸附剂(Ca/CTS/FA)用于酸性大红3R(Acid scarlet3R,AS 3R)染料的吸附去除,考察了最佳吸附条件和吸附性能,探讨了吸附动力学、吸附热力学及复合吸附剂的再生。结果表明:水体p H、吸附剂投加量、吸附时间和振荡频率均对吸附有影响。在不同温度下,Ca/CTS/FA对AS 3R的吸附动力学均能用准二级吸附速率方程精确描述(R~2=1.00)。不同温度下的等温吸附数据分别用Langmuir模型、Freundlich模型和Dubinin-Radushkevich(D-R)模型进行拟合,结果表明等温吸附行为更符合Langmuir模型,同时也较好地符合Freundlich模型和D-R模型;由D-R方程获得的平均吸附能、表观活化能及热力学研究均表明该吸附过程由化学吸附、物理吸附和氢键作用共同控制。热力学参数中吸附自由能变为负值、焓变为正值说明该吸附是吸热性质的自发过程。Ca/CTS/FA复合吸附剂能用0.01 mol·L-1Na OH溶液再生,至少可循环使用8次以上,再生率均在99%以上。     

草木灰与化肥配施对玉米农艺性状及产量的影响

[目的]研究草木灰与化肥配施对玉米生长及产量的影响,探讨施用草木灰后玉米生长变化规律,筛选出适宜配比,为农田合理配施草木灰、提高作物产量提供参考。[方法]以玉米为试材,采用田间试验方法,对比草木灰与氮、磷、钾化肥配施,玉米株高、穗长、穗粗、百粒重及产量表现。[结果]草木灰与氮磷肥配施,玉米株高、穗长、穗粗、百粒重及产量均高于氮钾和磷钾配施处理,分别比对照高15.41 cm、1.83 cm、0.48 cm、6.16 g,产量达10 938.85 kg/hm~2,比对照(CK)增产37.91%,比施用氮磷钾化肥增产1.86%。与氮磷钾3种营养元素配施,玉米产量为11 036.35 kg/hm~2,比对照(CK)增产39.14%,比施用氮磷钾不施草木灰处理增产2.77%,两者差异不显著。[结论]草木灰与化肥配合施用,玉米农艺性状表现良好,且能提高产量。玉米田草木灰与氮磷钾化肥配合施用,优选氮肥、磷肥,在农业生产中,可用草木灰替代钾肥与氮磷肥配施,减少无机钾肥的施用量,增加玉米产量。     

Potential use of wood ash in South African forestry: a review

The use of landfills as a disposal method for wood ash is costly, environmentally detrimental and is pitted against increasingly stern environmental regulations. Literature has shown that wood ash has the potential to be used as a forest fertiliser and the effects tend to be highly site-specific. Wood ash contains a combination of carbonates, hydroxides and other calcium-containing minerals that are responsible for the liming effect observed following application to soils. In addition, it contains significant magnesium and potassium concentrations, but little nitrogen and sulphur. The phosphorus availability of wood ash varies considerably and in effect can limit soil phosphorus uptake and may affect subsequent nutrient balance in plants. Short-rotation forestry practices and whole-tree harvest systems can induce periodic or persisting nutrient deficiencies and acidify the soil. This may affect the ability of a site to sustain adequate nutrient levels over successive rotations. Utilising wood ash as a soil amendment can offset or correct some nutrient deficiencies and imbalances induced by intensively managed plantation forests. This review covers the international literature on ash applications to forest land, including the effect of ash-beds remaining after slash burning (as a useful analogy for the effects of wood ash on soil properties and tree growth). The results show that ash applications to forest land can be done safely and can potentially stimulate microbial activity and improve pine and eucalypt growth. Safe ash application rates should be determined after consideration of (1) soil buffer capacity and ash alkalinity (expressed as calcium carbonate equivalence) and (2) an evaluation of the concentrations of heavy metals existing in soils and present in the available ash, particularly from cadmium, chromium, lead and arsenic.     

不同改良剂对退化黄壤及其下渗水养分的影响

以添加了改良剂的退化黄壤为研究对象,通过种植莴笋―空心菜―莴笋的盆栽试验,对比分析添加生物质灰渣改良剂与其他改良剂对蔬菜产量、土壤养分的影响,并进一步研究了不同改良剂处理下,退化土壤下渗水养分状况,以期为综合评价改良剂的修复效果提供科学依据。结果表明:(1)NPKH(氮磷钾化肥配施灰渣)和NPKW(氮磷钾化肥配施生物质肥)处理的莴笋产量增幅最大;(2)经改良剂处理的退化土壤有机质的含量和p H提高,随种植时间增加,土壤有机质含量均下降,但NPKH处理的下降幅度最小,其次为NPKC(氮磷钾化肥配施草炭)处理;各改良剂处理对碱解氮的影响差异并不明显,NPKH处理较其他处理能显著提高土壤有效磷(P)、速效钾(K)含量,其中有效P较NPK(单施化肥)处理提高了190.0%~242.9%;(3)单施化肥在退化土壤上易造成氮素的流失(总氮(TN)流失浓度22.08~39.06 mg L~(-1)),NPKH、NPKW和NPKC处理的下渗水TN浓度均低于其他处理;NO_3~--N是土壤氮素损失的主要形式,其变化趋势与TN较一致,呈极显著的相关关系(p0.01,r=0.869);在整个盆栽过程中,土壤下渗水总磷(TP)、可溶性磷(DP)浓度呈极显著的相关性(p0.01,r=0.892),DP浓度占TP的60%以上;NPKH处理中的灰渣含有大量的磷元素,除供作物生长外,部分会随水流失,其下渗水中TP和DP分别为0.70~1.35 mg L~(-1)和0.67~1.27 mg L~(-1),明显高于其他处理,易造成水体富营养化。