Study On Immobilized Microorganisms In The Treatment Of High Ammonia-nitrogen Wastewater

Water is all of the life on those planets. With the rapid development of the industry andurban construction, water pollution in our country has also increased. In addition, the shortageof per capita water resources has been seriously restricted the sustainable development of oureconomy. It does great harm to ecological environment. In recent years, the discharge ofindustrial waste water with high ammonia-nitrogen concentration are on the increase.Although the efficiency of high ammonia-nitrogen wastewater treatment improvescontinuously in China, the high cost of wastewater treatment disadvantage does generallyexist in traditional water treatment technology. Therefore, the development of economic andefficient wastewater treatment technology to reduce the investment and the operating costsplays an important role in economic development and environmental protection.In some biological wastewater treatment applications, with the development of the newmaterial and the perfection of the matching technology, Aerated Biological Fluidized Tankprocess grows rapidly. The process has many advantages, such as small occupation, highburthen capability, without back washing, no return sludge, and no sludge bulking, etc. It hasbeen used for the wastewater secondary and the deep treatment of municipal wastewater, coal,papermaking, medicine and electricity, etc. But because of the low efficiency ofmicroorganisms in wastewater treatment, the operating costs of the process have beenincreased. In order to make better use of microorganisms in treating wastewater to increaseefficiency of microorganisms and reduce the operating costs of the process, in this article,JHE-1, JHE-3and porous spherical suspended carriers were chose as microorganisms carriers,aerobic biological fluidized bed technology (ABFT) was adopted to degrade highammonia-nitrogen wastewater. The effects of the dosage of immobilized microorganisms, pHvalue, the hydraulic retention time (HRT) and the aeration flux were studied and acquiredmany achievements, the best microorganisms carriers and the best optimal conditions for thebiological wastewater treatment were chose.(1) In different conditions of the dosage of immobilized microorganisms, pH, HRT andthe aeration flux, JHE-1carriers were chose as microorganisms carriers for the single factorexperiment and the orthogonal experiment of the biological wastewater treatment. Theexperiment results showed that, under the condition of the dosage of immobilizedmicroorganisms70mg/L, pH8, the hydraulic retention time (HRT)4days and the aerationflux0.9L/min, the removal rate of ammonia-nitrogen could be raised to92%.(2) In different conditions of the dosage of immobilized microorganisms, pH, HRT andthe aeration flux, JHE-3carriers were chose as microorganisms carriers for the single factorexperiment and the orthogonal experiment of the biological wastewater treatment. The experiment results showed that, under the condition of the dosage of immobilizedmicroorganisms130mg/L, pH7.5, the hydraulic retention time (HRT)5.5days and theaeration flux0.9L/min, the removal rate of ammonia-nitrogen could be raised to91%.(3) In different conditions of the dosage of immobilized microorganisms, pH, HRT andthe aeration flux, the porous spherical suspended carriers were chose as microorganismscarriers for the single factor experiment and the orthogonal experiment of the biologicalwastewater treatment. The experiment results showed that, under the condition of the dosageof immobilized microorganisms200mg/L, pH7.5, the hydraulic retention time (HRT)5.5days and the aeration flux0.9L/min, the removal rate of ammonia-nitrogen could be raised to83%.(4) Through the comparison with the experiment, we know that the effects of threecarriers vary in high ammonia-nitrogen wastewater treatment, JHE-1carriers have goodhydrophile, the microorganisms grow well on it, the removal rate of ammonia-nitrogen washigh; the microorganisms on JHE-3carriers have a good adaptability to weak alkalienvironment, but the dosage of immobilized microorganisms are high, the hydraulic retentiontime (HRT) is long; the microorganisms on the porous spherical suspended carriers also havea good adaptability to weak alkali environment, but the dosage of immobilizedmicroorganisms are high, the hydraulic retention time (HRT) is long, the removal rate ofammonia-nitrogen was low. The order of the influential factor on the removal rate ofammonia-nitrogen from high to low is: pH, the hydraulic retention time (HRT), the aerationflux.(5) Of the three carriers, JHE-1carriers have the highest removal rate ofammonia-nitrogen. Through the comparison with field experiment, the utilization of themicroorganisms increased.(6) Through the material accounting, the treatment costs can save14.8million yuan ayear in this conditions, the operating costs reduce obviously.