Discharge Standard Of Water Pollutants Research Articles

Pre-precipitation of Sewage-SNAD Granular Sludge Process Test

Using artificial water, the simultaneous partial nitrification, ANAMMOX (anaerobic ammonium oxidation), and denitrification (SNAD) granular sludge process was started in a sequencing batch reactor (SBR), and then the ammonia concentration in the influent was reduced gradually. After stable operation for a period of time under the low ammonia concentration, sewage treated by a pre-precipitation process was used as a substrate to investigate the performance and stability of the SNAD granular sludge process. The results show that after the SNAD process was successfully started, the ammonia removal rate was greater than 98%, and total the nitrogen removal rate was about 89%. As the influent ammonia concentration decreased, the nitride-oxidizing bacteria (NOB) activity was increased and the total nitrogen removal rate gradually decreased to 75%. When the pre-precipitated domestic sewage (NH4+-N 52-63 mg·L-1, COD 99-123 mg·L-1) was used as the inflow, the average effluent removal rate of the total effluent was 73.2%, the effluent COD concentration was below 35 mg·L-1, and the maximum effluent ammonia nitrogen and total nitrogen concentration were 0.7 mg·L-1 and 12.8 mg·L-1. The ammonia and total nitrogen concentration in the continuous 30 day effluent reached the 1A level of the integrated discharge standard of water pollutants for municipal wastewater treatment, indicating that the removal of organics and nitrogen from domestic sewage was achieved efficiently and synchronously.

Startup Strategies for the SNAD Granular Sludge Process at Low Temperature

To study the effect of the startup strategies on the simultaneous partial nitrification, ANAMMOX, and denitrification (SNAD) granular sludge processes, these processes were initiated by starting the completely autotrophic nitrogen removal over nitrite (CANON) process and anaerobic ammonia oxidation-denitrification (SAD) process at 12.7℃ and 18.3℃, respectively. The results show that the ammonia nitrogen was almost completely removed and the total nitrogen removal rate reached 86.7% after the R1 reactor was successfully started. When the ammonia concentration was low, the total nitrogen removal rate in the effluent decreased to 75.3%, the total nitrogen concentration in the effluent was~10 mg·L-1, and excessive proliferation of the NOB was observed. The total nitrogen concentration in the effluent exceeded the 1A level of the integrated discharge standard of water pollutants applied in Beijing City. After the R2 reactor was successfully started, the effluent contained almost no ammonia nitrogen and the total nitrogen removal rate was~89.1%, that is, slightly higher than that of the R1 reactor. When the ammonia concentration was low, the concentration of ammonia nitrogen in effluent was less than 1.0 mg·L-1 and the total nitrogen concentration in the effluent was less than 6 mg·L-1. The concentrations of ammonia nitrogen and total nitrogen in the effluent reached the 1A level of the integrated discharge standard of water pollutants applied in Beijing City. First, the startup of the SAD process gradually eliminated the NOB from the system through anaerobic operation in the initial stage of the startup, maintained the stability of the system, provided a good basis for the subsequent aeration to start the SNAD process, maintained the stable operation of the reactor, and the long-term discharge of total nitrogen reached the standard.

Current Situation and Future Development Direction of Water Utilization in Chinese Steel Industry

Considering the serious shortage of water in China, there are two main problems of water utilization in steel plants. One is to save fresh water consumption, and the other is to reduce the waste water discharge. In 2012, the fresh water consumption and the waste water discharge of Chinese key steel plants accounted for 1.2% and 2.4% of the industry sectors. The discharge standard of water pollutants for steel plants in China is more and more rigorous. Since the new century, the specific fresh water consumption per ton steel of Chinese key steel plants was reduced from 25.24t in 2000 to 3.25t in 2015 by technical progress, such as coke dry quenching (CDQ), dry de-dusting of blast furnace gas (BFG) and converter gas (BOFG), etc. Technologies for saving fresh water and reducing waste water discharge will be developed in the future. Seawater desalination technique will be developed in the eco-industrial port zones of steel plants to reduce the ground water extraction. Civil sewage will be processed and used in the suburban steel plants. These two demonstration projects have been built in Shougang Jingtang steel plant and Tangshan steel plant respectively.

Research on the large-scale application of nitrogen removal for the treatment of synthetic ammonia wastewater

The capability of anoxic–aerobic (A/O) process treatment and influencing factors of high concentration ammonia industrial wastewater were studied in this paper. Results showed that the A/O process system had achieved favorable performance and the quality of effluent could meet the direct emission standard of Discharge standard of water pollutants for ammonia industry (GB13458-2013) under the optimal conditions as follows: the perfect inflow loading of ammonia 0.12 kg/(m3 d), the mixed liquid recycle ratio (R) 200%, and sludge return ratio 80%, the carbon-to-nitrogen ratio (C/N ratio) 4.5–5.5. Besides, the results also confirmed that the activity of nitrifying bacteria in activated sludge was greatly inhibited due to the high concentration of free ammonia (FA). In addition, carbon shortage had a marked effect on the denitrification efficiency of the system.

Research on the Effects of Modified HDPE for Wastewater Treatment

MBBR processes improve reliability, simplify operation and require less space than traditional wastewater treatment systems. The performance of biological membrane carriers is very important to MBBR operating efficiency. Modified HDPE material is more hydrophilic and electropositive. The experiment indicates that: The grafting percent is 3.67% at 40 min exposing time in Acetone-AA-BP system. The outflow CODCr and NH3-N removal efficiency is 87.57~93.12% and 68.82~76.33% respectively in modified HDPE system. The outflow CODCr and NH3-N concentration is content to II series in Discharge standard of water pollutants (DB 11/307-2005).

Tertiary Treatment of Paper Industries Effluent with Advanced Electrochemical Oxidation Process in the Presence of Modified Bentonite Powdery Electrodes

Tertiary treatment wascarried out to treat pulp and paper effluent from secondary treatment processby a three-dimensional electrode system equipped with modifiedbentonites as powdery electrode. The cetyl trimethylammonium bromide modified bentonite (CTAB-bent) and hydroxy-aluminum pillaredorganic bentonite (OH-Al-CTAB-bent) were synthesized and characterized by XRDand FTIR spectroscopy analysis.The impacts such as the dosage of particle electrode, electrolysis times,current density were on the COD removal efficiency and decolorization effect ofeffluent were also investigated. The results showed that the experimentscarried out by three-dimensional electrode system with OH-Al-CTAB-bent weresufficient for the COD and color removal efficiency. A current density of 30mA/cm2, electrolysis time of 40min, and the particle electrodedosage of 1.6g/L were selected as an optimum conditions that allows fast andlow cost treatment. The effluent can achieve the discharge standard of waterpollutants for pulp and paper industry (GB3544-2008) after electrolysis.

Feasibility Study on Satisfing Standard of Water Pollutants for Pulp and Paper Industry

Contrasting《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2008) to《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2001), this article educes impact for pulp and paper industry by 《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2008). This article discuss producing technics and dealing with waste water technics of pulp and paper industry, that satisfy GB3544-2008.

Experimental Study on Combined Process of EOW and MBR for Treatment of UDMH Wastewater

The combined process of Electrolyzed oxidizing water(EOW)and membrane bioreactor(MBR)was applied to treat the UDMH wastewater, and its treatment efficiency was compared with that by MBR alone．In the combined process, the treatment efficiency of UDMH wastewater is better than MBR alone. When the influent COD and UDMH are 800 to 1000 mg•L-1and 300 mg•L-1, the effluent COD and UDMH are about 55 mg•L-1and 0.3 to 1.5 mg•L-1respectively, close the demand of the Discharge standard of water pollutants for space propellant．In the MBR process alone，the effluent COD and UDMH are about 90 mg•L-1and 45 mg•L-1respectively, which worse than the combined process EOW-MBR, especially the effluent UDMH far beyond the demand of the Discharge standard of water pollutants for space propellant．

The Practice of the Printing and Dyeing Wastewater Treated by the Process of the First Coagulation Sedimentation/Hydrolysis Acidification/Anoxic/Oxic System/Secondary Coagulation Sedimentation

Printing and deying wastwater was one of the wastewater of difficulty biological treatment. the process of the coagulation sedimentation/hydrolysis acidification/Anoxic/Oxic System/coagulation sedimentation was adopted to treat the printing and dyeing wastewater, the wastewater after disposal had reached the first discharge standard of the discharge standard of water pollutants for dyeing and finishing of textile industry ( GB 4287 -92).

Treatment of simulated brominated butyl rubber wastewater by bipolar membrane electrodialysis

A large amount of wastewaters containing sodium bromide (NaBr) is usually generated during the production of brominated butyl rubber; it can cause contamination of the environment. In this study, a method was reported to regenerate hydrobromic acid (HBr) and sodium hydroxide (NaOH) from a simulated NaBr wastewater by bipolar membrane electrodialysis (BMED). Sodium hydroxide may be recycled in the neutralization washing process of preparing the brominated butyl rubber. The effects of operation parameters, such as sodium bromide concentration, current density, and initial acid and base concentrations, on regeneration were analyzed, on the basis of proper energy consumption and current efficiency. The results indicated that a low energy consumption and a high current efficiency were achieved when the concentration of sodium bromide was in the range of 11,000–16,000 mg/L with both the initial concentration of the acid and base at about 0.10 mol/L. Additionally, it was also demonstrated that a high current density applied to the BMED stack usually resulted in both higher energy consumption and current efficiency. Finally, a discharged NaBr concentration of 133.9 mg/L, which was far below the discharge standard of water pollutants for industry, could be obtained from the initial concentration of 16,000 mg/L after the operation of BMED process for 3.5 h. Therefore, this process cannot only achieve the elimination of environmental pollution, but also the recycling of resources.

Treatment of gasification effluent of fertilizer with biochemical united technology

Introduced the technology and application of treating the gasification effluent of fertilizer with the physical-chemistry and biochemistry united technology. The technology is simple and viable, and occupies less land. When the main equipment runs normally, the gasification effluent of fertilizer treated with the united technology reached the requirement by second-degree discharge standard of the ‘Discharge standard of water pollutants for synthesize ammonia industry’.