Entity

Time filter

Source Type


Liu Z.-H.,Beijing Institute of Technology | Ge Y.-S.,Beijing Institute of Technology | Tan J.-W.,Beijing Institute of Technology | Fan S.-B.,Beijing Municipal Research Academy of Environmental Protection | And 2 more authors.
Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology | Year: 2010

To evaluate the consistency of ESC (European steady cycle) and ETC (European transient cycle) model with bus driving cycle and to compare the emission discrepancy between legislation limits and real-time measurement, the bus driving cycle survey and real-time emission test have been conducted. The statistical characteristic of bus driving cycle was derived from the clustering analysis of driving cycle survey. Four buses which have the same characteristic were chosen to conduct real-time measurement using SEMTECH portable gaseous pollutant analyzer. The results indicate that there have great differences between the bus real-time driving cycle and regulations of ESC stable model and ETC transient model. The CO and NOx emission of the four buses exceed the limits frequently though the engines of the buses did pass the ESC and ETC legislation. In other words, the existing models can not control buses emission effectively. It is necessary to develop a special model for approving bus type on test bench or use portable emission test equipments as a supplement measurement. Source


Qu Y.,CAS Institute of Process Engineering | Wei Q.,Beijing Municipal Research Academy of Environmental Protection | Wei Q.,Beijing University of Chemical Technology | Li H.,CAS Institute of Process Engineering | And 3 more authors.
Bioresource Technology | Year: 2014

Ionic liquid (IL) has been widely investigated in 5-HMF production from biomass. However, most of studies employed IL as reaction solvent which requires a large amount of IL. In the present study, IL was utilized as catalyst in the conversion of microcrystalline cellulose (MCC) to 5-HMF under microwave irradiation (MI) in N,N-dimethylacetamide (DMAc) containing LiCl. 1,1,3,3-tetramethylguanidine (TMG)-based ILs, including 1,1,3,3-tetramethylguanidine tetrafluoroborate ([TMG][BF4]) and 1,1,3,3-tetramethylguanidine lactate ([TMG]L) which were commonly used in the absorption of SO2 and CO2 from flue gas, were synthesized and applied in the conversion of MCC to 5-HMF for the first time. Of the catalysts employed, [TMG]BF4 showed high catalytic activity in 5-HMF production from MCC. The condition including the ratio of IL to MCC, temperature and time for MCC conversion was optimized using Central Composite Design (CCD) and Response Surface Methodology (RSM). The highest 5-HMF yield of 28.63% was achieved with the optimal condition. © 2014 Elsevier Ltd. Source


Liang K.-Q.,Beijing Municipal Research Academy of Environmental Protection | Liang K.-Q.,National Engineering Research Center for Urban Environmental Pollution Control | Xiong Y.,Beijing Municipal Research Academy of Environmental Protection | Xiong Y.,National Engineering Research Center for Urban Environmental Pollution Control | And 7 more authors.
Huanjing Kexue/Environmental Science | Year: 2012

Based on high SS/BOD and low C/N ratio of waste water of municipal wastewater treatment plant, the structure of currently existing hydrolysis reactor was reformed to improve the influent quality. In order to strengthen the sludge hydrolysis and improve effluent water quality, two layers water distributors were set up so that the sludge hydrolysis zone was formed between the two layers distribution. For the purpose of the hydrolysis reactor not only plays the role of the primary sedimentation tank but also improves the effluent water biodegradability, input water ratios of the upper and lower water distributor in the experiment were changed to get the best input water ratio to guide the large-scale application of this sort hydrolysis reactor. Results show, four kinds of input water ratio have varying degrees COD and SS removal efficiency, however, input water ratio for 1:1 can substantially increase SCOD/COD ratio and VFA concentration of effluent water compared with the other three input water ratios. To improve the effluent biodegradability, input water ratio for 1:1 was chosen for the best input water ratio. That was the ratio of flow of upper distributor was 50%, and the ratio of the lower one was 50%, at this case it can reduce the processing burden of COD and SS for follow-up treatment, but also improve the biodegradability of the effluent. Source


Xiong Y.,China University of Geosciences | Xiong Y.,Beijing Municipal Research Academy of Environmental Protection | Wang Q.,Xinjiang Akesu Water Group | Song Y.-H.,Beijing University of Chemical Technology | And 2 more authors.
Huanjing Kexue/Environmental Science | Year: 2013

In order to strengthen the sludge hydrolysis and improve effluent carbon source, the structure of currently existing hydrolysis reactor was reformed. The new process combined separation of suspended solids in influent and hydrolysis of settled sludge. Experimental results show that the removal rate of SS was 81.4%, the average SS/BOD5 ratio of effluent was dropped to 0.4, far less than that of the influent ratios; SCOD/COD and COD0.45~5/COD ratio of the effluent increased by 35.4% and 17.7%, but the COD>100/COD ratio reduced by 53.2%; BOD5/TN ratio increased from 3.7 to 4.7 and the BOD5/TP ratio from 23.8 to 36.4. The improvement of effluent carbon source was helpful for nitrogen and phosphorus removal in follow-up process. Meanwhile, the hydrolytic rate of sludge was up to 51.9%, realizing the reduction and resource-regeneration. Source


Liang K.,Beijing Municipal Research Academy of Environmental Protection | Zhou J.,Huazhong University of Science and Technology | Xiong Y.,Beijing Municipal Research Academy of Environmental Protection | Tao T.,Huazhong University of Science and Technology
Huazhong Keji Daxue Xuebao (Ziran Kexue Ban)/Journal of Huazhong University of Science and Technology (Natural Science Edition) | Year: 2012

Taking urban sewage of low C/N ratio as a treatment object in a productive scale test, different efficiency on nitrogen removal of the hydrolysis-A/O (anoxic-oxic) process at different nitrification liquid-reflux-ratio was studied. Simultaneously, the influence of nitrification liquid-reflux-ratio on nitrogen removal efficiency was discussed as the relative ratio of removal quantities was used for the evaluation. Results show that hydrolysis-A/O process has high removal efficiency of COD, TN, NH4 +-N, TP, and the average removing efficiency is 84.0%, 64.2%, 98.2% and 73.2% respectively. Apart from TP and SS, the A standard of GB18918-2002 is reached by other index. Meanwhile, it is more efficient when the nitrification liquid-reflux-ratio at the high ratio condition. Comparing with the condition of the nitrification liquid reflux ratio at 100%, the hydrolysis-A/O process system and the hydrolysis process system output water concentration of COD, NH4 +-N, TN, TP are 8.90, 0.07, 3.74, 0.58 mg/L and 25.40, 6.22, 4.09, 1.46 mg/L lower respectively when the nitrification liquid reflux ratio at 200 %. Because of different water quality conditions of the experiment at each stage, the material balance equations is done and the relative ratio of removal quantities per hour index βj, i is used for the evaluation of the removal ability of pollutant in different nitrification liquid reflux ratio. Evaluation results show that in the high nitrification liquid reflux ratio the hydrolysisi pool has higher removal capacity and then the removal loading of the A/O biological pool is reduced, at this case, pullutants removal ability of the entire process is enhanced. Source

Discover hidden collaborations