Modeling urban pollutant wash-off processes with ecological memory.

Urbanization increases the extent of impervious surfaces, runoff, sediment, and nutrient loadings downstream, leading to the deterioration of urban surface waters. During pollutant wash-off from urban surfaces, the peak concentration of pollutants typically occurs after the rainfall peak. However, current urban wash-off models do not consider this time delay, assuming that the effect of rainfall on the wash-off process is immediate.

Contribution of road dust from Low Impact Development (LID) construction sites to atmospheric pollution from heavy metals.

The re-suspension of road dust due to intense Low Impact Development (LID) construction activities may be a major contributor to atmospheric metal pollution. However, the distribution characteristics, mobility potential, and pollutant load of atmospheric particles at LID construction sites are not clear. Consequently, management practices to mitigate air pollution from LID construction are lacking.

[Evaluation of Effect of Urban Non-point Source Pollution Control on Porous Asphalt-Bio-retention Combined Roads].

Different combinations of low impact development (LID) technologies can be applied for control of urban non-point source pollution. There are currently few evaluations of urban non-point source pollution and pollution load reduction based on a combination of porous asphalt and bio-retention. Taking Shenzhen International Low Carbon City as an example, road-deposited sediments were collected prior to and after rainfall events.

Influence of low impact development construction on pollutant process of road-deposited sediments and associated heavy metals.

Intense Low-Impact Development (LID) construction in China could lead to increasingly severe stormwater and receiving water pollution due to the lack of appropriate regulation for mitigating pollution from LID construction. Samples of road-deposited sediments (RDS) were collected from 50 study sites at seven LID construction stages and four road hierarchies to analyze the pollution process and determine the size of the region influenced by LID construction. Six heavy metals were analyzed, and the RDS index model was adopted to estimate the potential heavy metal load washed off by stormwater runoff.

Feasibility and simulation model of a pilot scale membrane bioreactor for wastewater treatment and reuse from Chinese traditional medicine.

The lack and pollution of water resource make wastewater reuse necessary. The pilot scale long-term tests for submerged membrane bioreactor were conducted to treat the effluents of anaerobic or aerobic treatment process for the high-strength Chinese traditional medicine wastewater. This article was focused on the feasibility of the wastewater treatment and reuse at shorter hydraulic retention time (HRT) of 5.

[Characteristics and operation of enhanced continuous bio-hydrogen production reactor using support carrier].

A kind of granular activated carbon, whose granular size is no more than 2mm and specific gravity is 1.54g/cm3, was used as the support carrier to allow retention of activated sludge within a continuous stirred-tank reactor (CSTR) using molasses wastewater as substrate for bio-hydrogen production. Continuous operation characteristics and operational controlling strategy of the enhanced continuous bio-hydrogen production system were investigated.

[Application of denaturing gradient gel electrophoresis and temperature gradient gel electrophoresis in microbial molecular ecology].

In recent years, denaturing gradient gel electrophoresis (DGGE) and temperature gradient gel electrophoresis (TGGE) are well-established molecular tools in microbial molecular ecology that allows the study of diversity and dynamics of microbial communities. The technique is reliable, reproducible rapid and inexpensive. Here, the principle, the limitations and potentials application of DGGE/TGGE techniques are introduced in this paper.

[Start-up and continuous operation of bio-hydrogen production reactor at pH 5].

A continuous stirred-tank reactor(CSTR)for bio-hydrogen production using molasses wastewater as substrate was investigated. Emphasis was placed on assessing the start-up and continuous operation characteristics when keeping pH value constant. It was found that at pH of 5, biomass of 6g/L, organic loading rate (OLR) of 7.

[Application of PCR-DGGE to resolve microbial diversity in bio-hydrogen producing reactor].

To reveal microbial diversity of anaerobic activated sludge in bio-hydrogen producing reactor, sludge in different period were sampled and their genomic DNA of microbial community was extracted directly. After purification of the genomic DNA using DNA gel recovery kit, the 16S rRNA genes (V3 region) were amplified by using the universal primers (F338GC and R534). The result of agarose gel (2%) electrophoresis show that the PCR products were about 200bp.

Monitoring of microbial community structure and succession in the biohydrogen production reactor by denaturing gradient gel electrophoresis (DGGE).

To study the structure of microbial communities in the biological hydrogen production reactor and determine the ecological function of hydrogen producing bacteria, anaerobic sludge was obtained from the continuous stirred tank reactor (CSTR) in different periods of time, and the diversity and dynamics of microbial communities were investigated by denaturing gradient gel electrophoresis (DGGE). The results of DGGE demonstrated that an obvious shift of microbial population happened from the beginning of star-up to the 28th day, and the ethanol type fermentation was established. After 28 days the structure of microbial community became stable, and the climax community was formed.

[Continuous operation of hydrogen bio-production reactor with ethanol-type fermentation].

The natural response of a continuous stirred tank reactor (CSTR) for hydrogen bio-production using molasses wastewater as substrate was investigated. Emphasis was placed on assessing the operational controlling strategy on the stable operation of CSTR with high efficiency. It was found that at an initial biomass of 15g/L, an equilibrial microbial community in the ethanol-type fermentation and efficient stable operation of CSTR could be established with following conditions: temperature of 35 degrees C +/- 1 degrees C, COD organic loading rate (OLR) of 40kg/(m3 x d), hydraulic retention time (HRT) of 4h, pH value of 4.