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201.
胡椒大、中量元素的含量在不同树龄中有所不同,幼龄期以氮最高,其N:P2O3:K2O:Ca:Mg为1:0.15:0.53-0.9:0.22-0.38:0.15-0.30;成年龄则以K2O最高,N:P2O3:K2O:Ca:Mg为1:0.13:1.32:0.44:0.16.在不施微肥的情况下,胡椒叶片缺B、Mo、Zn.成年龄胡椒各养分含量都是从萌芽期(收获后)开始,随生育期的进展而增加,到果实成熟期下降.一株中产胡椒N、P2O5、K2O总吸收量为282.4g,其比例为1:0.19:0.9.  相似文献   
202.
炼油厂汽提废水含较高浓度的酚 ,会对污水处理场产生冲击。采用上流式曝气生物滤池对废水进行预处理工业试验 ,取得了满意的试验结果 :出水酚浓度低于 9.0mg/L ,酚降解率 >90 % ,完全可以消除它对污水处理场的冲击。并通过工业试验为工艺设计和工业运行确定了有关参数和运行条件。  相似文献   
203.
在分析各种运行参数对雾化效果影响的基础上 ,介绍了喷雾增湿塔用离心式雾化器的选型与放大设计的方法。  相似文献   
204.
Decolorization of textile wastewater by photo-fenton oxidation technology   总被引:16,自引:0,他引:16  
Kang SF  Liao CH  Po ST 《Chemosphere》2000,41(8):1287-1294
This paper describes the use of photo-fenton process for color removal from textile wastewater stream. The wastewater sample to be treated was simulated by using colorless polyvinyl alcohol (PVA) and reactive dyestuff of R94H. As a result, the hydroxyl radical (HO*) oxidation can effectively remove color, but the chemical oxygen demand (COD) was removed in a slight degree. The color removal is markedly related with the amount of HO* formed. The optimum pH for both the OH* formation and color removal occurs at pH 3-5. Up to 96% of color can be removed within 30 min under the studied conditions. Due to the photoreduction of ferric ion into ferrous ion, color resurgence was observed after 30 min. The ferrous dosage and UV power affect the color removal in a positive way, however, the marginal benefit is less significant in the higher range of both. PVA as the major background COD of a textile wastewater stream inhibits the color removal insignificantly as its concentration increases.  相似文献   
205.
A multi-step mass transfer-biodegradation model is developed to describe the bioactive adsorber dynamics for the biotreatment of livestock generated odor causing VOCs (VOC-odor) based on a biologically active dust particle (BADP) process. The BADP process employs dust particles with adsorbat-acclimated microbial culture to form the bioactivated dust particles (BDP) for the simultaneously adsorption, mass transfer, and biodegradation of VOC-odor. The model incorporating age and size distributions of BDP considers the equilibrium partitioning of VOC-odor at BDP and bulk gas interface that followed by two kinetic processes occurring in the bulk and solid phases: bulk gas mass transfer-biodegradation and BDP biofilm diffusion-biodegradation. Analytical equations indicate that the overall biotransformation rate of VOC-odor in a BADP process is controlled by BDP-bulk gas equilibrium processes represented by the slowest of two kinetic processes determined by a dimensionless group: the Thiele modulus (phi 2), the Damkohler number (Da) and the Biot number (Bi). Computer simulations demonstrate that the most favorable performance of a BADP system in reducing VOC-odor concentrations is operated under Bi < 1, Da < 1, or Bi > 1 phi 2 < 1; indicating diffusion-biodegradation controlled. The dimensionless group can be used to identify the dominant rate-limiting processes and to evaluate the overall biomineralization rate in a BADP process. Simulation results allow the determination of preliminary design for prototype development.  相似文献   
206.
Anaerobic digestion of polyelectrolyte flocculated waste activated sludge   总被引:5,自引:0,他引:5  
Chu CP  Lee DJ  Chang BV  You CH  Liao CS  Tay JH 《Chemosphere》2003,53(7):757-764
This work examined how adding one of three polyelectrolyte flocculants (T3052: cationic, T2000: non-ionic, and T1052: anionic) affected the anaerobic digestion of wastewater sludge. Methane production, floc characteristics (morphology and zeta-potential) and process parameters (soluble chemical oxygen demands (SCODs) and reductive potentials) were monitored along the digestion tests. The digestion rates of T2000- and T1052-conditioned sludge resembled that for original sludge. The T3052-flocculated sludge generated methane at a higher rate during the first 6 days of digestion than did the original one. In the following stage, the digestion rate of sludge flocculated with T3052 at dosage exceeding 15 g/kg dried solids declined. For example, at 40 days of digestion the methane production amounts for original, 15 g/kg DS flocculated, and 40 g/kg flocculated sludge were of 136, 105, and 85 g/kg DS, respectively. The role of flocculants could change in different stages of digestion.The dosed polymers had no apparent toxicity to the inoculum used. The changes in SCOD, adenosintriphosphate concentrations, oxidative and reductive potential, and zeta-potentials did not correlate with the noted hindered digestion for T3052-conditioned sludge. Microphotographic observation revealed that the flocs of T3052-conditioned sludge were not only of a large size, but also were resistant to structural deterioration during digestion. Therefore, mass transfer resistance was proposed to account for the hindered digestion efficiency observed for T3052-conditioned sludge.  相似文献   
207.
Lee CC  Chen HL  Su HJ  Guo YL  Liao PC 《Chemosphere》2005,59(10):1465-1474
The aim of this study was to evaluate the PCDD/Fs patterns in ambient air based on data information emitted from incinerator generated from ambient air measurements and those in serum. Four circular zones, namely A, B, C, and D, were identified based on simulated ambient annual average PCDD/Fs concentrations, from a selected municipal waste incinerator. Sixteen ambient samples were taken from the 4 circular zones across 4-seasons. Eighty-nine volunteers were recruited according to the demographic distribution within each zone. PCDD/Fs profiles were documented both for air and serum samples collected. Comparing to the congener patterns from ambient air and serum samples, we found that OCDD, OCDF, 1,2,3,4,6,7,8-HpCDD, and 1,2,3,4,6,7,8-HpCDF were the predominant groups among 17 congeners from both the ambient air and serum sample. And, factor analysis showed the distribution patterns of PCDD/Fs from ambient air and serum samples are almost identical across different zones, except for congener patterns of serum samples from residents in zone C. In addition, the average PCDD/Fs level significantly reduced for about 10 folds than those of the other three seasons when the incinerator was shut down in one of sampling periods. We might conclude that ambient air exposure was the most important contributor to PCDD/Fs levels in ambient air but not the single in serum. Therefore, another or more powerful source, such as occupational exposure, dietary intake or the consumption of local food, should be further investigated at the same time.  相似文献   
208.
对钠盐型和铵盐型含硫工业废水进行脱硫处理,采用均匀设计法设计试验,得到定量描述试验内在规律的多元非线性回归方程.用该回归方程计算的预测值与试验结果一致.对影响脱硫效果和脱硫效率的影响因素--絮凝剂投加量、pH以及废水含硫量进行了考察.利用回归方程,对反应体系进行了模拟优化处理.研究表明,在试验条件下,用聚合氯化铝作为絮凝剂、pH=7的条件下,采用两段工艺,可以使脱硫后废水含硫量降至40 mg/L以下,满足下游污水处理装置对含硫量的要求.  相似文献   
209.
活性炭纤维(ACF)电极法处理染料废水的探讨   总被引:40,自引:4,他引:40  
贾金平  杨骥 《上海环境科学》1997,16(4):19-22,25
根据Advanced Chemical Oxidation^[1][6]的原理,通过ACF电极的引入,使得电化学处理成为一个自由基反应与絮凝反应相结合的过程,对于多种模拟印染废水可以具有良好的处理效果。通过与其他方法的对比实验,表明在色度去除率方面不比Fenton试剂法逊色,并明显优于絮凝法。经过单级处理,对于实验范围内的还原染料、酸性染料、活性染料及硫化染料,其脱色率全部大于90%,大多数为98  相似文献   
210.
厦门中华白海豚的重金属含量   总被引:5,自引:0,他引:5  
对厦门港海域8只中华白海豚成体和幼仔体内的重金属含量进行了测定。结果表明,与鱼类和无脊上比,中华白海豚的重金属含量很高。成年的含量观于幼仔;肝的含量大大超过其他部位。中华白海豚的重金属含量高,与其它处于海洋食物链的的最顶级密切相关。  相似文献   
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