废聚苯乙烯泡沫塑料的回收利用

将废弃的聚苯乙烯泡沫塑料回收利用既可解决它所带来的污染,又可缓解化工能源不足问题。本文对废旧聚苯乙烯泡沫塑料的再生利用进行了研究。     

猪粪便污水PSB液肥化及其对绿豆插条不定根发生的促进作用

研究结果表明,用猪粪便污水培养光合细菌(简称PSB)生产PSB液肥是可行的,但须进行预酸化处理;猪粪便污水发酵液(CODcr2 173 mg/L)通过8 d培养获得的光合细菌液肥PSB含量可达4.5×108MPN/mL。采用蒸馏水、“绿泉”植物营养液和光合细菌液肥(分别稀释50、100、200和400倍)等6种供试液进行绿豆不定根发生生物试验。结果表明:光合细菌液肥能明显促进绿豆插条不定根发生,其中稀释200倍液的绿豆不定根数量、长度和生物量与蒸馏水处理相比,分别增加24%、57%和73%,而且不定根出现时间比蒸馏水提早3 d。猪粪便污水光合细菌液肥化技术,可为农业循环经济的实施提供很好的技术支持,有助于禽畜养殖业的可持续发展。     

蠕虫(蚯蚓)处理生物垃圾的初步研究

利用蚯蚓的生理代谢活动来处理生物垃圾,从而改变土壤的理化性质,提高土壤肥力,改善土壤中的氮、磷和钾等元素的含量,同时蚯蚓自身也得以存活和增殖。试验通过测定经蚯蚓消化代谢后的生物垃圾,从产物中找出氮、磷、钾的变化规律。同时试验表明蚯蚓的周繁殖率为34%,单独个体日处理生物垃圾量为0.957 g。利用蠕虫(蚯蚓)对生物垃圾进行处理不仅可获得良好的环境效益、生态效益,同时通过蚯蚓增殖更可获得较好的经济效益。     

烟草综合利用现状及其前景

目前我国种植的烟草主要用作卷烟原料,但烟草栽培上的副产物以及卷烟工业中的废次物占其生物学产量一半以上,如何合理综合利用烟草关系到我国烟草农业以及卷烟工业的可持续发展。从烟草各个部位、卷烟工业废次物以及转基因烟草三个方面对国内外烟草综合利用的现状作一简要综述,并对烟草的综合利用前景进行展望。     

Using the RUSLE to identify factors controlling erosion rates of mine soils

Observable differences in particle size, smoothness and compaction between cap site (slope 2·8 per cent) and batter site (slope 20·7 per cent) surfaces on the waste rock dump at Ranger Uranium Mine were quantified in terms of revised universal soil loss equation (RUSLE) parameter values. Cap site surface material had a K_m (erodibility corrected for sediment density) of 0·030 and batter site surface material had a K_m of 0·0056. Using these K_m values (derived from particle size distributions), slope length and steepness (LS) factors of 0·36 for the cap site and 3·66 for the batter site, and a cover (C) factor of 0·45 for the cap site and 0·16 for the batter site, the RUSLE predicts an erosion rate from the cap site that is 1·9 times greater than erosion from the much steeper batter site. The RUSLE indicates that the finer particle size and blocky soil structure of the cap site (D₅₀ = 0·91 mm) compared with the looser granular structure of the batter site (D₅₀ = 1·74 mm) strongly influence erosion. The predictions are similar to observed soil losses from erosion plots on these sites under rainfall simulation events, for which the measured erosion rate from the cap site was approximately twice that from the batter site. For the RUSLE to predict the observed erosion rates, the support practice (P) factor for the cap site would have to be approximately 30 per cent greater than the P factor for the batter site. The higher cap site P factor probably results from smoothing and compaction caused by vehicle movement across the surface. Compaction is considered to have greatly reduced infiltration capacity, thus increasing the erodibility of the cap site. Vehicles probably also crushed the surface material at the cap site, creating the observed finer particle size distribution and further increasing the erodibility. Compaction, through its effects on erodibility (K_m) and surface roughness (P), is concluded to be the major cause of higher erosion from the cap site, even though the slope steepness is 10 times less. Parameterisation of the RUSLE quantifies the differences between sites and explains the unexpected erosion rates observed. The results highlight the need for careful management of rehabilitated sites to avoid increases in erosion which may arise from compaction by machinery.     

四川省秸秆和畜禽粪便县域分布特征和资源化利用潜力

为明晰四川省近年秸秆和畜禽粪便分布格局和特征,基于2018年四川省县域尺度主要粮油作物产量和畜禽出栏量,通过空间分析明确四川主要粮油作物秸秆(水稻、小麦、玉米、油菜)和畜禽粪便(牛、羊、猪、家禽)资源分布状况及聚集区,探讨各县秸秆和畜禽粪便循环利用潜力和途径。结果表明：四川省2018年秸秆可收集总量为2 808.55万t,呈现“一个中心,东密西疏”的分布规律,秸秆种类以玉米和水稻秸秆为主;畜禽粪便总量为8 162.02万t,呈现“三个中心,外密内疏”的分布规律,猪粪占绝对优势,占比高达57.8%。2018年四川省秸秆肥料化理论上可节约当年全省7.4%氮肥和5.0%磷肥投入,可全量替代当年全省钾肥用量,秸秆能源化可替代1 422.71万t标准煤或6.22×10⁹m³沼气。2018年四川省畜禽粪便全部肥料化可节约当年全省42.6%氮肥投入,可全量替代当年全省磷肥和钾肥用量,畜禽粪便能源化利用可折算成835.19万t标准煤或4.15×10⁹m³沼气。99%、95%和90%置信区间秸秆热点县分别有30、40...     

利用不同无机和有机固体废物配制技术新成土的研究

为拓展固体废物的利用途径,以生活污泥、蚯蚓粪、秸秆、粉煤灰、煤渣为原料通过为期3个月的室内恒温培养来制备技术新成土,研究不同原料配比对技术新成土理化性质的影响。结果表明：制备的技术新成土pH在7.08～7.69之间,水稳性团聚体总量为49.83%～86.44%,团聚体破碎率为13.10%～32.20%,平均质量直径和几何平均直径分别为0.54～1.04 mm和0.54～0.89 mm。培养后技术新成土的氮、磷、钾速效养分分别下降了11.03%～38.08%、5.79%～25.06%、0.11%～10.52%,总有机碳含量在5.26%～8.74%之间,整体养分含量处于较高水平。DTPA提取态Zn含量升高了15.74%～102.40%,DTPA提取态Cd含量降低了17.39%～65.02%。生物毒性实验表明有9种处理不会对植物生长产生明显影响,有3种处理需要对配方进行调整。综合pH、团聚体总量及稳定性、养分含量来看,所制备的技术新成土的性质基本达到了自然土壤的正常范围,可以用于土壤复垦、改良或代替部分自然土壤。污泥会导致处理中重金属Zn含量较高,因此制备的技术新成土应避免种植蔬菜、粮食等农...     

农田尾菜发酵过程中农药残留变化特征

基于尾菜中存在农药残留的现状,以设施农业尾菜黄瓜秧为研究对象,采用气相色谱法和超高效液相色谱-串联质谱法检测了尾菜黄瓜秧在静态好氧发酵过程中多菌灵、吡虫啉、哒螨灵等50种农药残留的动态变化,并分析发酵重要影响因子堆高对农药残留消解的影响。结果表明:在尾菜黄瓜秧中共检测出腐霉利、多菌灵、嘧菌酯、苯醚甲环唑、烯酰吗啉、虫螨腈、吡虫啉、啶虫脒和哒螨灵9种农药残留,其中多菌灵平均残留量最高,达11.2 mg/kg,其他8种农药平均残留量在0.042~0.89 mg/kg之间。在发酵的24 d中,不同堆高条件下9种农药的消解规律均符合一级反应动力学方程,但不同农药半衰期差异较大,其中吡虫啉的平均半衰期最长,为28.9 d,多菌灵的平均半衰期最短,为10.2 d;不同堆高处理中农药的消解速率也有差异,总体上在2.5 m堆高下各农药的消解率最高、半衰期最短。本研究结果可为尾菜发酵参数优化、农业废弃物的高效资源化利用以及研发基于尾菜发酵产物的有机蔬菜专用有机肥提供理论支撑。     

稻草与牛粪混合腐解的最佳配比筛选

【目的】以腐殖质组成特征为评价依据,筛选稻草与牛粪混合腐解的最佳配比,为两类农业固体废弃物的资源化应用提供参考。【方法】以稻草和牛粪为材料,采用室内培养法,研究稻草与牛粪质量比为10∶0(Rs),9∶1(Rd1),7∶3(Rd2),5∶5(Rd3),3∶7(Rd4),1∶9(Rd5)和0∶10(Dm)混合腐解90 d,各处理水溶性物质(WSS)、可提取腐殖酸(HE)、胡敏酸(HA)、胡敏素(Hu)组分的有机碳含量(依次表述为C_(WSS)、C_(HE)、C_(HA)、C_(Hu)),以及胡敏酸碱溶液E_4/E_6、腐殖化系数(C_(HA)/C_(FA))的动态变化,筛选稻草与牛粪腐解的最佳配比。【结果】与0 d相比,在腐解完成(90 d)后,各处理C_(WSS)含量均有不同程度降低,相比于稻草,牛粪腐解后更易促进微生物对C_(WSS)的利用,使其下降86.2%;Rd2和Rd5处理使物料C_(HE)含量分别增加10.2%和28.6%,其余处理C_(HE)均有不同程度消耗;与0 d相比,腐解完成后,Rd1、Rd3和Dm处理均有助于C_(HA)的积累,其中牛粪腐解更易促进C_(HA)的形成,使其增加30.5%。在各处理下,物料HA分子均先发生降解、脂族化,而后逐渐缩合、芳香化,但HA分子结构仍趋于简单;在促进HA分子脂族化方面,Rd4处理的优势最大,而Dm处理更有利于HA结构的稳定。Rd3处理在促进腐殖质品质方面的贡献最大,其次为Rd1处理,Dm和Rs处理次之,但Rd2和Rd5处理不利于腐殖质品质的改善;Rs、Rd1、Rd2、Rd3和Rd4处理在腐解过程中更有利于C_(Hu)的分解,且Rd3处理的优势最大,使C_(Hu)含量下降91.0%,而牛粪比例≥90%更有助于C_(Hu)的累积。【结论】稻草与牛粪按照质量比5∶5混合腐解,易促进C_(Hu)的分解和C_(HA)的积累,利于腐殖质品质提升。     

Geomorphic estimates of the stability of a uranium mill tailings containment cover: Nabarlek,Northern Territory,Australia

The geomorphic stability of the cover (cap) over the pit of Nabarlek Uranium Mine in Arnhem Land, Northern Australia, is important because radon gas and other long-lived radio-nuclides arising from mill tailings must be contained for long periods. The primary agents of denudation in the region's seasonally wet tropical environment of low relief are rainwash, overland flow, rilling and gullying. Other agents of erosion are of less concern, although biogenic agents of erosion (e.g. termites and windthrow) may enhance fluvial activity. A combination of modelling, using the Universal Soil Loss Equation, and analogue estimates of denudation and thresholds of rilling and gullying from areas with similar geology, topography and climate are used to estimate the stability of the Nabarlek cover. Denudation rates are conservatively estimated at less than 100mm ky⁻¹. It is suggested that with some minor design modifications the cover will retain its integrity for several thousand years.