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961.
962.
Strategy for olive mill wastewater treatment and reuse with a sewage plant in an arid region. 总被引:1,自引:0,他引:1
This study was conducted to evaluate the treatability of OMW (olive mill wastewater) with sewage and sewage sludge, which could supplement nutrients and microbes required for OMW treatment and reduce its possible toxicity. The amount of OMW added to an aeration tank was based on the loading difference between the designed and actual COD loads, while the amount added to anaerobic digestion for energy recovery was determined by CH4 production. The COD removal efficiencies were 70-85% for both systems. Compost of OMW with dried sewage sludge also showed a similar temperature profile without OMW addition. This strongly suggested that OMW can be treated at a sewage plant without pretreatment and the treated effluent can be reused in irrigation for an arid region. 相似文献
963.
The secondary effluent from municipal plants in Korea generally represents higher BOD with lower SS. Therefore, more soluble forms of organics and NH4-N need to be removed to improve its effluent for reuse. In this study reuse possibility of secondary effluent and CSO (combined sewer overflow) using BAF (biological aerated filter) was evaluated. The tertiary application with 1.2 h EBCT, SS, BOD and COD showed stable concentrations less than 1.3, 1.3 and 6.2 mg/L, respectively. Nitrogen could be nitrified even at 7 degrees suggesting BAF can be used for a water reuse method as well as an effective add-on facility in cold regions. However, BAF was not stable with CSO application at increased flow rates suggesting CSO must be equalised prior to application. Disinfection was necessary even during normal weather conditions. 相似文献
964.
A method was developed to assess the heat insulation performance of intumescent coatings. The method consists of temperature measurements using the bench‐scaled experimental set‐up of a cone calorimeter and finite difference simulation to calculate the effective thermal conductivity dependent on time/temperature. This simulation procedure was also adapted to the small scale test furnace, in which the standard time–temperature curve is applied to a larger sample and thus which provides results relevant for approval. Investigations on temperature and calculated effective thermal conduction were performed on intumescent coatings in both experimental set‐ups using various coating thicknesses. The results correspond to each other as well as showing the limits of transferability between both fire tests. It is shown that bench‐scaled cone calorimeter tests are a valuable tool for assessing and predicting the performance of intumescent coatings in larger tests relevant for approval. The correlation fails for processes at surface temperatures above 750°C, which are not reached in the cone calorimeter, but are attained in the small scale furnace set‐up. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
965.
966.
Male weanling rats were subjected to standard 28-day PER trials following the outline by the AOAC (1984) except that the diets contained 8.5% protein (N × 6.25) as one of six wheat-based breakfast cereals, white flour, whole wheat flour or casein. One of the cereals was an extrusion puffed product, three were flaked and toasted cereals and two were extruded cereals. Of the two extruded cereals, one was lightly toasted and the other was more heavily toasted. Relative PER (R-PER) was lowest for the puffed cereal (- 15.3) and highest for the extruded-lightly toasted cereal (69.9). R-PER for the flaked cereals ranged from 1.7 to 16.3; the other extruded cereal had a R-PER of 2.8 and each of the two flours had a R-PER of 42.9. 相似文献
967.
968.
969.
Summary Fourier transform infrared spectroscopy and birefringence measurements have been used to study the changes in molecular orientation which occur on drawing of plasticized as compared to pure polystyrene (PS) at a temperature T=Tg+Cte. No influence of plasticizers on orientation can be detected whatever the interactions between small molecules and PS chains are. Comparison with previous results obtained on PS-poly(vinylmethyl ether) compatible blends confirms the importance of the macromolecular nature of the second component to enhance the friction coefficient leading to higher level of chain orientation. 相似文献
970.