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891.
以某生产有机颜料厂家为例,介绍了EGSB TCBS处理工艺.当废水中CODCr质量浓度为7 000~8 000mg·L-1,NH3-N质量浓度为200~300 mg·L-1,SS的质量浓度为1 000~2 000 mg·L-1时,采用该工艺处理后,出水ρ(CODCr)<1 000 mg·L-1,ρ(NH3-N)<30 mg·L-1,ρ(SS)<500 mg·L-1.表明EGSB TCBS工艺适应于有机颜料废水的处理,且工艺运行便利,剩余污泥量小. 相似文献
892.
Winter losses of nitrogen and phosphorus from Italian ryegrass, meadow fescue and white clover in a northern temperate climate 总被引:1,自引:0,他引:1
Ievina Sturite Trond Maukon Henriksen Tor Arvid Breland 《Agriculture, ecosystems & environment》2007,120(2-4):280-290
We have studied to what degree Italian ryegrass (Lolium multiflorum Lam.), white clover (Trifolium repens L.) and meadow fescue (Festuca pratensis L.) are able to preserve nitrogen (N) and phosphorous (P) in shoots and roots from one growing season to the next in a northern temperate climate. Field experiments were performed during four consecutive winters in central southeast Norway (60°42′N, 10°51′E), and N and P in plant biomass were measured in the autumn and in the spring. We also measured the contents of total N, total P and organic carbon (C) in seepage water that percolated through the aboveground plant material. Uptake of N and P in Italian ryegrass and white clover was substantially larger than in meadow fescue. The winter losses varied greatly from year to year, depending on the winter climate. On the average for all three of the plant species, the winter losses of N from aboveground biomass were 6, 35, 68 and 10% in the four experimental years, respectively. The corresponding P losses were 11, 36, 60 and 22%. On the average for all plant species and experimental years, 43 (±12)% (S.E., n = 12) of the N, 34 (±9)% of the P and 4 (±1)% of the C that was lost from the aboveground plant biomass during the winter, was recovered in seepage water, basically as a nutrient pulse in melt water in early spring. The very low C recovery rate in seepage water suggested a considerable microbial growth on lost plant C. Assuming that all un-recovered plant C was consumed by microorganisms not included in measurements of the seepage water, modelling showed that microbial immobilisation theoretically might explain the unexpectedly low recovery rates of N and P. The study was not designed to investigate the possible effects of psychrophilic microbes on N and P cycling. Therefore, it is inconclusive and underlines the need for more knowledge on this matter. 相似文献
893.
以生化法处理有机污染物的系统为讨论对象 ,从底物负荷影响微生物生长的角度出发 ,通过对有机污染物负荷与生化反应速度之间的关系的分析 ,得出进口底物浓度的大小会影响生物反应器内微生物的量的多少 ,从而影响器内的生化反应速率的结论 ,并按照“稳定平衡”假说的设想 ,建立了修正的Michaelis -Menten公式 相似文献
894.
TiO_2太阳能光催化降解有机污染物的研究进展 总被引:2,自引:0,他引:2
以太阳能为激发光源的 Ti O2 光催化氧化技术是一项极具运用前景的绿色环保技术。简要介绍了 Ti O2 光催化氧化的原理、催化剂 Ti O2 的制备研究、Ti O2 太阳能反应器的研制以及该项技术在有机污染物降解中的应用 相似文献
895.
896.
Phosphorus (P) is one of the main limiting plant nutrients in most tropical soils. Acquiring quantitative information on soil P status is essential for evaluating its sustainable management in agroecosystems. The objective of this study was to evaluate how land-use shifts from semi-permanent food crop systems (CF) to plantations of tea (Camellia sinensis) (TP) and Eucalyptus grandis (EP) impact on both organic and inorganic P species. Determination of phosphorus status combined a P sequential fractionation procedure and 31P nuclear magnetic resonance (NMR) spectroscopy. Sequentially extracted pools included available P by 0.5 M NaHCO3, Al/Fe-P by 0.1 M NaOH, Ca-P by 0.5 M HCl and residual P by 0.5 M H2SO4 after ignition at 550 °C. Soil total P (STP) varied significantly across land uses (P<0.05) with the lowest mean value (1025.6±23.1 mg kg−1) occurring under CF and the highest (1698.0±86.1 mg kg−1) under TP. The largest P-pools were NaOH-P (47–51% of total soil P) and H2SO4-P (25–32%). NaHCO3-Pi under fertilized land uses (CF and TP) was greater than 12 mg kg−1 indicating that these systems were sustainable. Unfertilized EP was P-deficient, probably as the result of organic-matter accretion and subsequent P immobilization in organic forms. 31P NMR revealed that 88–89% of P compounds in NaOH extract were organic with monoester-P accounting for 59.1–60.8%. This was followed by diester-P (9.8–12.4%), teochoic acid (8.4–10.1%), orthophosphate (8.8–9.7%), unknown compounds (7.4–8.4%), pyrophosphate (1.1–4.6%) and phosphonate (0–1.3%). EP had higher diester-P and no phosphonate compound whereas CF had substantial amount of pyrophosphate (4.6%) and less orthophosphate and teochoic acid. These results indicate that these last P compounds are easily mineralizable P forms participating actively in plant P nutrition. 相似文献
897.
898.
城市垃圾焚烧处理中重金属和有机氯化物的二次污染与防治 总被引:17,自引:0,他引:17
概述城市垃圾焚烧法处理的二次污染问题,着重分析重金属和有机氯化物二次污染物的形成和排放机制,结合我国实际,提出我国垃圾焚烧处理中重金属和有机氯化物二次污染的防治措施。 相似文献
899.
利用有机肥大田定位试验,研究有机肥及其施用方法对水旱轮作的红壤磷吸附和解吸特征的影响.结果表明,施用有机肥料后土壤对磷的吸附量减少.吸附结合能常数K值下降,土壤对磷的亲和力减小.有机肥集中施于冬作的处理其吸附量小于分两季施用的处理.与吸附相反,吸附量大的处理其解吸量小,施用有机肥后,磷解吸量增加.有机肥集中施用的处理其解吸量高于分两季施用的处理.有机肥对低平衡浓度下的磷的解吸影响最大,即有机肥能促进高能吸附阶段的磷的解吸,由于这一阶段吸附的磷通常是很难解吸的,因此这对提高磷的有效性有极其重要的意义. 相似文献
900.
改良剂对铅锌尾矿污染土壤上龙须草生长和叶片叶绿素含量的影响 总被引:9,自引:0,他引:9
采用盆栽试验,研究了4种改良剂对铅锌尾矿污染土壤中龙须草生长和叶片叶绿素含量的影响。结果表明,改良剂处理土壤生长的龙须草长势明显优于对照,地上部生物量均显著高于对照(P≤0.05),增产效果均〉100%。4种改良剂缓解污染土壤中重金属对龙须草毒害作用的大小顺序为钙镁磷肥〉碳酸钙〉有机肥〉海泡石。4种改良剂在不同处理浓度下对龙须草生物量和叶绿素含量的影响趋势表现出一定的相关性,其中随着碳酸钙处理浓度的增加,龙须草生物量和叶绿素含量呈下降趋势;其他3种改良剂随着处理浓度的升高,龙须草生物量呈上升趋势,而叶绿素含量则呈先上升后下降的趋势。 相似文献