Publications by authors named "De-Xiang Liao"

In this study, honeycomb cinders were employed to remove phosphate and Chemical Oxygen Demand (COD(cr)) simultaneously for landfill leachate treatment. Operating conditions of honeycomb cinders pretreatment, pH, temperature, honeycomb cinders dosage, reaction time, and settling time, were evaluated and optimized. The results revealed that the removal efficiencies of both phosphate and COD(cr) could be increased up to 99.

View Article and Find Full Text PDF

Deammonification process was started-up in a sequencing batch reactor (SBR) seeded with anaerobic granular sludge. A kinetic model describing deammonification process was proposed. Due to the presence of concentration gradient of dissolved oxygen (DO) in granular sludge, model correction factors of DO were introduced.

View Article and Find Full Text PDF

An SBR reactor seeded with anaerobic granular sludge was started up to enrich deammonifition bacteria and investigate its nitrogen removal characteristics. Research results showed that deammonification granular sludge could be cultivated successfully with firstly enriched ANAMMOX microorganisms in anaerobic condition and then controlled the dissolved oxygen in the SBR reactor between 0.3 and 0.

View Article and Find Full Text PDF

The performance of phosphorus removal with a sequencing batch reactor was investigated by simulated municipal wastewater. The experimental results showed that phosphorus removal could be achieved in sequencing batch reactor without anaerobic phase, which was conventionally considered as a key phase for phosphorus removal. Phosphorus concentration in the effluent was 1.

View Article and Find Full Text PDF

The presence of heavy metals in municipal sludge restricts its use for agricultural purposes. In this paper, the bioavailability and eco-toxicity of heavy metals in municipal sludge was evaluated, taking into consideration both the speciation of metals and the local environmental characteristics. The dewatered municipal sludge samples were collected from five sewage plants in Changsha, Zhuzhou and Xiangtan respectively, which are representative cities with characteristics of the middle-south region of China.

View Article and Find Full Text PDF

Biosorption potential of Penicillium simplicissimum (Penicillium sp.) immobilized within loofa sponge (PSILS) for lead and copper from aqueous media was explored. The effects of pH, contact time and initial concentration were studied in batch experiments.

View Article and Find Full Text PDF

The performance of biological phosphorus removal (BPR) in a sequencing batch reactor (SBR) with single-stage oxic process was investigated using simulated municipal wastewater. The experimental results showed that BPR could be achieved in a SBR without anaerobic phase, which was conventionally considered as a key phase for BPR. Phosphorus (P) concentration 0.

View Article and Find Full Text PDF

Objective: To isolate the bioflocculant-producing bacteria from activated sludge and investigate the flocculating characteristics of the newly isolated bioflocculant.

Methods: Bacteria were screened from activated sludge samples to isolate bioflocculant-producing bacteria. Flocculating activity was used as a measure of the flocculating capability of the bioflocculant.

View Article and Find Full Text PDF

Hydrogen production by sterilization, microwave and ultrasonication pretreated waste sludge was investigated in this study. A new strain of Pseudomonas sp. GZ1 (EF551040) was inoculated in pretreated waste sludge to produce hydrogen.

View Article and Find Full Text PDF

An SBR reactor seeded with anaerobic granular sludge was started-up to enrich ANAMMOX (anaerobic ammonia oxidation) bacteria and investigate its nitrogen removal characteristics. Research results showed that hydraulic retention time (HRT) was the most important factor to enrich ANAMMOX bacteria. When the HRT was controlled at 30 d during the initial cultivation, the SBR reactor presented ANAMMOX activity at t = 58 days.

View Article and Find Full Text PDF

The performance of simultaneous nitrogen and phosphorus removal with an inner loop sequencing batch reactor were investigated by simulated municipal wastewater. The experimental results showed that COD, NH4(+) -N, and TP can be removed efficiently after four hours aeration, during which dissolved oxygen concentration was at 6 mg/L at the beginning of aerobic phase and pH was in the rang of 7 - 8. The COD and NH4+ -N as well as TP concentration in the effluent were about at 4 - 48 mg x L(1), 0 - 2.

View Article and Find Full Text PDF

Combination of a nitritation process and anoxic ammonium oxidation (ANAMMOX) process for the treatment of ammonia rich influents is evaluated. Herein the combined process was studied with manmade synthetic wastewater. Research results show that when the hydraulic retention time (HRT) was I day, the nitritation activity was stable and the influent ammonium concentration has little effect on it.

View Article and Find Full Text PDF