کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4481200 1623093 2015 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Cost-effective bioregeneration of nitrate-laden ion exchange brine through deliberate bicarbonate incorporation
ترجمه فارسی عنوان
زیست سازگاری مؤثر با محلول تبادل یونی نیترات از طریق ترکیب بی کربنات عمدی
کلمات کلیدی
استفاده مجدد از شور، قلیایی بی کربنات، مشتقات باکتریایی، آلودگی نیترات، آب آشامیدنی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی


• CaCl2-induced partial sulfate removal with little residual calcium.
• Salinity and alkalinity stabilization for stable brine biotreatment.
• Hematite-enriched high-density activated sludge for brine biotreatment.
• Sulfide-synchronized nitrate and nitrite reduction for carbon-limited denitrification.
• Use of biogenic alkalinity and CaCl2 to induce CaCO3 flocculation in post treatment.

Bioregeneration of nitrate-laden ion exchange brine is desired to minimize its environmental impacts, but faces common challenges, i.e., enriching sufficient salt-tolerant denitrifying bacteria and stabilizing brine salinity and alkalinity for stable brine biotreatment and economically removing undesired organics derived in biotreatment. Incorporation of 0.25 M bicarbonate in 0.5 M chloride brine little affected resin regeneration but created a benign alkaline condition to favor bio-based brine regeneration. The first-quarter sulfate-mainly enriched spent brine (SB) was acidified with carbon source acetic acid for using CaCl2 at an efficiency >80% to remove sulfate. Residual Ca2+ was limited below 2 mM by re-mixing the first-quarter and remained SB to favor denitrification. Under CO2–H−CO3CO2–HCO3− system buffered pH condition (8.3–8.8), nitrate was removed at 0.90 gN/L/d by hematite-enriched well-settled activated sludge (SVI 8.5 ml/g) and the biogenic alkalinity was retained as bicarbonate. The biogenic alkalinity met the need of alkalinity in removing residual Ca2+ after sulfate removal and in CaCl2-induced CaCO3 flocculation to remove 63% of soluble organic carbon (SOC) in biotreated brine. Carbon-limited denitrification was also operated after activated sludge acclimation with sulfide to cut SOC formation during denitrification. Overall, this bicarbonate-incorporation approach, stabilizing the brine salinity and alkalinity for stable denitrification and economical removal of undesired SOC, suits long-term cost-effective brine bioregeneration.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Water Research - Volume 75, 15 May 2015, Pages 33–42
نویسندگان
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