Preparation and application of embedded and immobilized Achromobacter sp. agent for effective removal of ammonia nitrogen from water

A novel wastewater-quality-improver, Sodium Alginate Embedded Microbe-treated Zeolite (SAEMZ), was proposed. The strains used are screened from black-odorous water and have high-efficiency NH4+-N degradation performance. The Gram-positive bacteria, belonging to Achromobacter sp., was determined through the screening and identification for this strain, whose removal rate of NH4+-N can reach 88.06%, to decrease the NH4+-N concentration from 61.83 mg/L to 7.80 mg/L, and its optimal growth conditions are pH 7-8, rotation speed 150-210 r/min, temperature 25-35 °C. The SAEMZ's removal effect on NH4+-N was considered in this research from aspects of reusability, storage stability, and the effects of dosage, coexisting ions, and wastewater's concentration. The increase of the SAEMZ's dosage effectively improved the NH4+-N removal rate; Ca2+ in the solution promoted the NH4+-N removal rate, while Mg2+ and Mn2+ inhibited it. Also, the NH4+-N removal rate improved slightly with Fe2+ concentration's increase and then decreased significantly; with the increase of the wastewater dilution factor, the NH4+-N removal rate showed an upward trend and with the increase of the SAEMZ's reuse times, it decreased. Therefore, recycle times should be controlled to less than 3 times in practical application; the SAEMZ still maintains its physiological stability, high mechanical strength, and good storage stability after being stored at 4 °C for 120 days.