柴油低温临界吸收法回收装车挥发油气

研究了采用柴油低温临界吸收法回收装车挥发油气的效果。实验结果表明：按装车挥发油气中的总烃体积分数为20.88%、装车挥发油气流量为280 m³/h、年运行时间为2 668 h计,装置年回收油气量为291 t,装置年最大运行功率为206.770 MW,装置投资回收期为3 a;处理后净化气中的总烃体积分数为1.24%,排放质量浓度低于25 g/m³,油气回收率达95%。处理后净化气满足GB 20950—2007《储油库大气污染物排放标准》,取得了较好的环保效益和经济效益。     

膜吸收法净化低浓度甲醛和氨气简

基于膜吸收技术自制双层平板式膜吸收器,搭建净化低浓度甲醛和氨气污染模拟系统,考察不同膜结构参数、进气流量、吸收剂流量等因素对其净化效果的影响。结果表明,聚偏氟乙烯PVDF对低浓度甲醛和氨气的净化效率高于聚四氟乙烯PTFE。对同一材质膜,随着膜孔隙率的增大,甲醛和氨气的净化率呈上升趋势。随着进气流量的增加,甲醛和氨气的净化效率降低;而吸收剂流量对其净化效率影响不大。对于所有实验条件,平均膜孔径为0.22 μm的PVDF 4^#在进气流量u_g=120 L/h时,甲醛和氨气的净化效率最高,分别达94.7%和96.3%。     

干式厌氧消化过程挥发酸对硫酸盐还原菌的影响

在牛粪干式厌氧消化过程中,通过添加不同挥发酸(乙酸、丙酸、丁酸),考察消化稳定阶段,挥发性脂肪酸的分布特征,挥发性脂肪酸酸组成变化对硫酸盐还原菌(SRB)的影响,微生物种群组成和种群间关系。实验结果表明,挥发性脂肪酸对SRB还原速率的贡献依次为:丙酸丁酸乙酸。相比乙酸和丁酸,添加一定量的丙酸,更有利于激活SRB的活性,从而加强SRB与产甲烷菌(MB)的种间协同,保证厌氧系统的稳定运行。     

Impacts of Suburbanization on Urban Eco-environment of Xi’an in China

Suburbanization in large cities is an important phenomenon in the process of urbanization development in China in recent decades,which plays a very important role in promoting city development,whereas some side effects on the eco-environment appeared at the same time.This paper,taking Xi’an City in China as a case study site,analyzed the features of population suburbanization and industry suburbanization and pointed out the impacts of suburbanization on urban eco-environment.Based on the research,suggestions of countermeasures for urban planning and municipal management of Xi’an City in protecting urban eco-environment and conserving natural ecology were put forward in the end.     

Incidence of polybrominated diphenyl ethers in central air conditioner filter dust from a new office building

This study examined polybrominated diphenyl ethers (PBDEs) in central air conditioner filter (CACF) dust from a new office building in Shenzhen, China. Human exposure to PBDE via dust inhalation and ingestion were also estimated. PBDEs level in CACF dust was lower than those in the other countries and regions. Approximately 0.671 pg/kg bw/day PM_2.5 (Particulate Matter up to 2.5 μm in size) bounded Σ₁₅PBDEs can be inhaled deep into the lungs and 4.123 pg/kg bw/day PM₁₀ (Particulate Matter up to 10 μm in size) bounded Σ₁₅PBDEs tend to be deposited in the upper parts of the respiratory system. The average total intake of Σ₁₅PBDEs via dust inhalation and ingestion for adults reached ∼141 pg/kg bw/day in this building. This value was far below the reference dose (RfD) recommended by United States Environmental Protection Agency. Human exposure to PBDEs via dust inhalation and ingestion in the new building is less than the old ones.     

Composition analysis and application of degradation products of whole feathers through a large scale of fermentation

Purpose

Feathers are one of the most abundant bioresources. They are discarded as waste in most cases and could cause environmental pollution. On the other hand, keratin constituted by amino acids is the main component of feathers. In this article, we reported on biorefined feathers and integrants and application of degraded products.

Materials and methods

The fermentation of whole chicken feathers with Stenotrophomonas maltophilia DHHJ in a scale-up of a 5-L bioreactor was investigated in this article. The fermentation process was controlled at 0.08 MPa pressure, 2.5 L/min airflow, and 300 rpm as 100% oxygen saturation level, 40°C, and pH 7.8.

Results

Feathers were almost completely degraded in the tested fermentation reaction with the following conditions: 80 g of whole feathers in 3 L fermentation broth for 72 h, seed age of 16 h, 100 mL inoculation amount, and 50% oxygen saturation level. The degraded products contain 397.1 mg/L soluble protein that has mass weight ranging from 10 to 160 kD, 336.9 mg/L amino acids, and many kinds of metal ions. The fermentation broth was evaluated as leaf fertilizer and found to increase plant growth to 82% or 66% for two- or fourfold dilutions, respectively. In addition, in a hair care assay, the broth showed a hair protective function by increasing weight, flexibility, and strength of the treated hair.

Conclusions

The whole feathers were degraded completely by S. maltophilia DHHJ. The degraded product includes many factors to life, such as peptides, amino acids, and mineral elements. It could be applied as leaf fertilizer and hair care product.     

Atmospheric particle characterization, distribution, and deposition in Xi'an, Shaanxi Province, Central China

Physical characterization and chemical analysis of settled dusts collected in Xi’an from November 2007 to December 2008 show that (1) dust deposition rates ranged from 14.6 to 350.4 g m⁻² yr⁻¹. The average deposition rate (76.7 g m⁻² yr⁻¹) ranks the 11th out of 56 dust deposition rates observed throughout the world. The coal-burning power was the major particle source; (2) on average (except site 4), ∼10% of the settled dusts having size <2.6, ∼30% having size <10.5, and >70% having size <30 μm; (3) the concentrations for 20 out of 27 elements analyzed were upto 18 times higher than their soil background values in China. With such high deposition rates of dusts that contain elevated levels of toxic elements, actions should be taken to reduce emission and studies are needed to assess the potential impacts of settled particles on surface ecosystem, water resource, and human health in the area.     

胶质芽孢杆菌、黑曲霉及与沸石联合对模拟废水中Fe3+处理研究

研究沸石、胶质芽孢杆菌(Bacillus mucilaginosus)、黑曲霉(Aspergillus Niger)、胶质芽孢杆菌与沸石联合以及黑曲霉与沸石联合对模拟废水中Fe3+的吸附等温曲线,分析它们对Fe3+模拟废水的吸附及絮凝作用。结果表明：沸石对Fe3+吸附作用符合Freundlich方程;胶质芽孢杆菌分泌含...     

超声波-铁粉协同降解五氯酚

通过超声波-铁粉联合体系协同降解废水中的五氯酚(PCP).实验结果表明:降解120 min后,PCP去除率可达90.4％;在该体系中铁粉被逐渐腐蚀成Fe2+,随降解时间的延长,Fe2+浓度逐渐增加;体系中的Fe2+可以促进·OH的产生,并且可以与超声空化作用下产生的H2O2发生Fenton试剂氧化反应降解PCP;超声波...     

化工建设项目环境影响评价中几个问题的探讨

从炼油厂煤制氢装置碳资源的利用、炼化装置所产生废物的焚烧处理、炼油装置加氢工艺技术的综合能耗、清洁生产标准的运用、废水处理及废水回用技术等方面对化工建设项目的环境影响评价中存在的问题进行了探讨,以促进我国化工建设项目环境影响评价工作的规范化和法制化.