화학적 응집 침전을 이용한 침출수 및 축산폐수의 처리 = Treatment of leachate and livestockwastewater using chemical precipitation methods

다국어 초록 (Multilingual Abstract)

Crystallization method such as struvite or hydroxyapatite formation is one of the promising methods in removing nitrogen and phosphorus simultaneously recalcitrant wastewater.
In these methods, Alkali is necessary in increasing pH because crystallization is occurred in high pH condition. NaOH has been traditionally used as alkali agent. On view of economic point, lime is cheaper than NaOH.
On this experiment, the feasibility of lime dose instead of NaOH was studied.
Using swine wastewater and leachate from landfill site, the feasibility of removing nutrient salts through struvite formation and the feasibility of using seawater or bittern as magnesium source in chemical coagulation process.
The results obtained from this experiments were summarized as follows.
1. When lime is used as alkali agent instead of NaOH, it is evident that struvite can not be formed because calcium ion presented in lime consumed phosphorus before struvite formation.
2. When seawater-lime coagulation process was applied to swine wastewater, the removal efficiency of ammonia-nitrogen showed 5374%. When bittern was used instead of seawater, the removal efficiency of ammonia-nitrogen ranged from 41% to 78%. In leachate treatment, ammonia-nitrogen removal efficiency showed 29%-52% and 36%-56%, when seawater-lime coagulation method and bittern-lime coagulation method were applied, respectively. In view of stoichiometric balance, it is evident that the main mechanism of ammonium removal was not struvite formation but ammonia stripping.
3. In case of chemical coagulation method using seawater or bittern as magnesium source and lime as alkali agent, COD removal efficiency of swine wastewater ranged from 61% to 79%. it is evaluated that such a removal efficiency is somewhat higher than removal efficiency by struvite formation. Accordingly, seawater-lime or bittern-lime coagulation process can be promising process for simultaneous treatment of nitrogen , phosphorus, COD when considering economic benefit.
4. When lime is used as alkali agent, phosphorus was removed completely because phosphorus was removed prior to struvite formation.
5. Optimum dosage of seawater was 5%, when the process performance was evaluated based on NH3-N, phosphate, COD removal efficiency.
6. NaCl concentration was calculated as 1500 mg/L, based on 5% seawater addition. Accordingly, biological inhibition due to salt concentration can be neglected in following biological treatment system.
7. It is evaluated that sludge recirculation without incineration prior to recycle is useless in view of process performance.

목차 (Table of Contents)

• 목차
• 목차 = i
• List of Table = iii
• List of Figure = iv
• I. 서론 = 1
• 1.1 연구의 필요성 = 1
• 1.2 연구 목적 = 3
• 1.3 연구 내용 = 3
• II. 문헌연구 = 4
• 2.1 응집 침전(Chemical Precipitation) = 4
• 2.2 응집 원리 = 4
• 2.3 Colloid 물질 = 5
• 2.4 응집제의 수중반응 = 7
• 2.5 응집제의 종류 = 8
• 2.6 침출수와 축산폐수의 수질특성 = 10
• 2.6.1 침출수의 수질특성 = 10
• 2.6.2 축산폐수의 수질특성 = 12
• 2.7 화학적 처리방법을 이용한 영양염류 제거방법 = 13
• 2.7.1 결정화에 의한 인의 제거방법 = 13
• 2.7.2 화학적인 질소 제거 = 19
• 2.7.3 결정화에 의한 질소와 인의 동시제거 = 20
• III. 실험방법 및 재료 = 22
• 3.1 실험재료 = 22
• 3.1.1 대상폐수 = 22
• 3.1.2 Magnesium and Phosphate source = 22
• 3.1.3 바닷물과 간수 = 22
• 3.1.4 PAC와 Alum = 23
• 3.2 실험장치 = 23
• 3.3 실험방법 = 23
• 3.3.1 해수-소석회 응집침전 및 간수-소석회 응집침전 실험 = 23
• 3.3.2 MAP침전에 의한 질소, 인 제거실험 = 24
• 3.3.3 PAC와 Alum을 이용한 응집침전 실험 = 24
• IV. 결과 및 고찰 = 26
• 4.1 화학적 응집침전을 이용한 축산폐수처리 = 26
• 4.1.1 해수-소석회를 이용한 응집침전 = 26
• 4.1.2 간수-소석회를 이용한 응집침전 = 29
• 4.1.3 PAC(폴리염화알루미늄), Alum(황산반토)을 이용한 응집침전 = 31
• 4.1.4 MAP 침전법을 이용한 응집침전 = 33
• 4.1.5 슬러지 재순환에 의한 영향 = 35
• 4.2 화학적 응집침전을 이용한 침출수처리 = 37
• 4.2.1 해수-소석회를 이용한 응집침전 = 37
• 4.2.2 간수-소석회를 이용한 응집침전 = 40
• 4.2.3 PAC(폴리염화알루미늄), Alum(황산반토)을 이용한 응집침전 = 42
• 4.2.4 MAP 침전법을 이용한 응집침전 = 44
• 4.2.5 슬러지 재순환에 의한 영향 = 45
• V. 결론 = 48
• 참고문헌 = 50
• Abstract = 54
• 감사의 글 = 56