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An Inexact Sequential Response Planning approach for optimizing combinations of multiple floodplain management policies

100%

Lu H., He L., Du P., Zhang Y.

Polish Journal of Environmental Studies

2014

tom 23

nr 4

This study proposes an inexact sequential response planning (ISRP) approach for floodplain management on the basis of two-stage stochastic programming techniques. It can facilitate rapid response decision making for upcoming severe flood disasters by efficiently operating available multiple control measures in a quantified manner. The case study considers a floodplain management problem where decision makers want to obtain a cost-effective combination of multiple floodplain management policies (i.e. constructing hydraulic engineering, flood diversion) for coping with the upcoming flooding disasters with various severity levels. Optimal management strategies obtained from ISRP are analyzed, following by the demonstration of extending potentials.

Organic matter and nitrogen distribution, and functional groups of filter at earthworm packing bed in vermifiltration

88%

Yang F., Wang L., Wang G., Du P., Zhang Y.

Polish Journal of Environmental Studies

2015

tom 24

nr 1

This paper studies organic matter (OM) and nitrogen (N) distributions at different depths of an earthworm packing bed, and the N distribution in situ solution in artificial soil (AS). The contents of OM, nitrate nitrogen (NO₃-N), ammonia nitrogen (NH₃-N), and total nitrogen (TN) changed along with the depth of AS. The results of N concentration in situ solution indicated that 35 cm to 40 cm thickness of earthworm packing bed thickness was optimal for removing NH₃-N and TN for synthetic wastewater treatment. Fourier transform infrared spectra showed that most intensity variations of the absorbance peaks increased in AS, decreased in detritus, and slightly changed in sand after synthetic wastewater treatment. Furthermore, certain functional chemical attributes might evaluate the OM contents at the VF media, and AS could act as the main matrices for OM reaction.

Treatment of mixed chemical wastewater by a two-stage A/O process for elimination of COD nitrogen and toxic matters

76%

Du P., Li W., Liang Z., Chen Y., Yang S., Yan F.

Polish Journal of Environmental Studies

2013

tom 22

nr 1

In our work a two-stage A/O system consisting of two independent A/O subsystems was used to remove high concentrations of COD, nitrogen, and toxic matter from mixed wastewater discharged by a comprehensive chemical group. The mixed liquid return was not adopted, and the sludge return ratio was kept at a high value of 100-200% to maintain high usable activated sludge concentration. Adequate NaHCO₃ was added to keep the influent alkalinity/KN ratio around 7.14 to 1. The system was running stably during the whole experimental period. Subsystem one obtained high COD and organic nitrogen removal capability without being influenced by the increasing COD loading. 87.6% COD was removed and 75.7% org-N was transformed to NH₄⁺-N. Due to the low COD/KN ratio created by subsystem one, the nitrification efficiency of subsystem two reached a high value of 92.1%. Besides, aerobic biological oxidation of oxic tank one showed excellent ability on toxic matter elimination. The acute toxicity of the whole system dropped from 0.165 to 0.042 mg HgCl₂/L. It has been proven by this study that, using the two-stage A/O system with sludge return only to treat COD nitrogen and toxic matters, laden mixed wastewater from comprehensive chemical groups may be feasible.

Ograniczanie wyników

3 Polish Journal of Environmental Studies

3 Du P.

2 Zhang Y.

1 Chen Y.

1 He L.

1 Li W.

1 Liang Z.

1 Lu H.

1 Wang G.

1 Wang L.

1 Yan F.

1 Yang F.

1 Yang S.

1 2015

1 2014

1 2013

Wyniki wyszukiwania

An Inexact Sequential Response Planning approach for optimizing combinations of multiple floodplain management policies

Organic matter and nitrogen distribution, and functional groups of filter at earthworm packing bed in vermifiltration

Treatment of mixed chemical wastewater by a two-stage A/O process for elimination of COD nitrogen and toxic matters