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391.
屠宰废水具有有机物含量高、可生化性较好等特点,因此生化处理是屠宰废水的主要工艺。某公司对屠宰废水采用"气浮-水解酸化-SBR"工艺进行处理,废水处理结果表明,当废水进水SS、COD cr、BOD5、NH3-N平均浓度分别为580 mg/L、1 900 mg/L、1 140 mg/L、54 mg/L时,出水SS、COD cr、BOD5、NH3-N平均浓度分别为45 mg/L、55 mg/L、15 mg/L、10 mg/L,出水水质指标满足《肉类加工工业水污染物排放标准》(GB 13457-92)的一级排放标准要求,废水中SS、COD cr、BOD5、NH3-N平均去除率分别为92%、97%、98.5%、72%。 相似文献
392.
The importance of soil organic carbon (SOC) under forests in the global carbon cycle depends on the stability of the soil carbon and
its availability to soil microbial biomass. We investigated the e ects of successive rotations of Chinese fir (Cunninghamia lanceolata
(Lamb.) Hook) plantations on the stability of SOC and its availability to microbes by adopting the two-step hydrolysis with H2SO4
and density fractionation. The results showed that successive rotations of Chinese fir decreased the quantity of total SOC, recalcitrant
fraction, and carbohydrates in Labile Pool I (LP I), and microbial properties evidently, especially at 0–10 cm horizon. However, cellulose
included in Labile Pool II (LP II) and the cellulose/total carbohydrates ratio increased in successive rotations of Chinese fir. The noncellulose
of carbohydrates included in LP I maybe highly available to soil microbial biomass. Hence the availability of SOC to microbial
biomass declined over the successive rotations. Although there was no significant change in recalcitrance of SOC over the successive
rotations of Chinese fir, the percentage of heavy fraction to total SOC increased, suggesting that the degree of physical protection for
SOC increased and SOC became more stable over the successive rotations. The degradation of SOC quality in successive rotation soils
may be attributed to worse environmental conditions resulted from disturbance that related to “slash and burn” site preparation. Being
highly correlated with soil microbial properties, the cellulose/total carbohydrates ratio as an e ective indicator of changes in availability
of SOC to microbial biomass brought by management practices in forest soils. 相似文献
393.
394.
高温菌的生理生化及其16S rDNA序列分析 总被引:1,自引:0,他引:1
利用高温菌耐热嗜热的特性和有机物好氧分解的基本原理,从厨余垃圾处理系统中分离筛选到6株在65℃能产生淀粉酶、脂肪酶、蛋白质酶及纤维素酶的高温高效菌种,并对其生理生化和16S rDNA进行了分析。结果表明:筛选出的6株高温菌,经鉴定都有芽孢,并具有兼氧性;对其进行16S rDNA区段序列测定显示,6株高温菌属于Geobacillus thermog lucosidasius菌种中的不同亚种;分离筛选出的高温菌经过2h的迟缓期后很快进入对数生长期,且持续时间较长,生长速度尤以HB6最快;6株高温菌株全部具有淀粉、纤维素、蛋白质降解活性,5株有脂肪降解活性。可见高温菌具有更高的有机物降解活性和更快的代谢速率,可提高有机物质的降解速率,缩短工艺运行时间,有利于工业化生产,在厨余资源化利用上具有广泛的应用前景。 相似文献
395.
Experimental study on pressurized activated sludge process for
high concentration pesticide wastewater 总被引:1,自引:1,他引:0
Pressurized biochemical process derived from traditional activated sludge processes is an innovative technology for wastewater treatment. The main advantage of the pressurized process is that the oxygen transfer barrier can be overcome by increasing the dissolved oxygen level. In this study, high concentration pesticide wastewater was treated by pressurized activated sludge process. It was found that the removal of chemical oxygen demand (COD) increased steadily with the increase of operating pressure, aeration time, and sludge concentration. When the operation pressure was 0.30 MPa and the aeration time was 6 hr, 85.0%–92.5% COD, corresponding to an effluent COD of 230–370 mg/L, was removed from an influent COD of 2500–5000 mg/L. The obtained outlet COD concentration was lower than 350–450 mg/L for the identical process operated under the atmospheric pressure. In addition, pressurized biochemical process could produce a higher COD volumetric loading rate at 5.8–7.6 kg COD/(m3·day), compared with 2.0–2.8 kg COD/(m3·day) using the same equipment at the atmospheric pressure. The COD concentration followed a modified Monod model with Vmax 2.31 day-1 and KS 487 mg/L. 相似文献
396.
分析了目前国内常规的对氨氮废水的处理方法,提出针对不同浓度的氨氮废水,采用不同组合的处理工艺,在使处理后的氨氮废水满足环保要求的前提下,做到工程的初期投资较少,管理运行费用较低,较好地达到经济和环境效益的统一。 相似文献
397.
The effects of deltamethrin at acute and sublethal concentrations on some hematological and biochemical profiles in the Indian major carp Labeo rohita have been examined. The lethal concentrations (LC50) of deltamethrin for 24 and 96 h were found to be 0.44 and 0.38 mg L?1, respectively. During acute treatment (24 h), hemoglobin (Hb), hematocrit (Hct), red blood cell (RBC), white blood cell (WBC), mean cellular volume (MCV), mean cellular hemoglobin (MCH), and mean cellular hemoglobin concentration (MCHC) values were significantly increased compared to control group. Plasma glucose, protein, cholesterol, albumin, globulin, triglyceride, and glycogen in gill and muscle were significantly decreased. Upon sublethal treatment (0.044 mg L?1, 10th of 24 h LC50), RBC and the biochemical parameters, except glucose and cholesterol, decreased significantly, while MCV, MCH, and MCHC values increased up to the 28th day and then declined. Cholesterol level was significantly increased throughout the study period. A biphasic response in the levels of Hb, Hct, WBC, and glucose were observed during sublethal treatment. 相似文献
398.
Hyperbaric oxygen increases the partial pressure of O2 in arterial blood and tissues and thereby relieves cellular hypoxia. We investigated whether this treatment changes biochemical parameters and intestinal mucosal barrier function in rats exposed to toxic levels of CO. Groups of ten Sprague–Dawley rats were treated with CO, with hyperbaric oxygen, or with CO followed by hyperbaric oxygen. A fourth group maintained under normal atmospheric conditions served as a control. CO poisoning increased red blood cell distribution width and the amount of alanine aminotransferase, urea nitrogen, and tight junction creatine kinase but decreased the mean corpuscular hemoglobin (Hb). These changes were reversed after hyperbaric oxygen therapy, which increased the number of red blood cells, hematocrit level, total protein, and Hb level. Hyperbaric oxygen therapy also increased tight junction protein 1 expression and reduced toll-like receptor 4 expression in the rat colon. In conclusion, hyperbaric oxygen resulted in an improved oxic condition in CO-poisoned rats and restored energy metabolism by repairing, to some extent, the organs injured by CO. The therapy may also improve the function of the intestinal mucosal barrier. 相似文献
399.
400.
光催化氧化与生物氧化组合技术对染料化合物降解研究 总被引:31,自引:1,他引:31
将多相光催化氧化法与生物氧化法相结合,探讨两种组合技术对染料化合物的降解。实验选用100ppm的甲基橙和典型实验溶液,适当配以一定浓度范围的生活污水,以保证生物菌种的生存条件。实验结果证明先生物氧化、后光催化氧化是一种比较好的组合方式,24h生物氧化,溶液COD去除达69.68%,色度去除达22.39%,随后光催化氧化1h,COD去除达84.65%,色度去除达91.31%。由此说明,这种组合方式可以体现出两种反应的互补性,尤其对生化处理后的残留色度有明显的改善。 相似文献