臺灣博碩士論文加值系統

電鍍工業為金屬表面處理業的一環，可增加物件的表面光澤與防蝕耐磨性以提昇物件的價值。但電鍍工業之製程中所排放廢水中常含有大量有害重金屬如銅、鉻、鉛、鐵、鎳、鋅等等，若未經妥善處理便任意排放，將會破壞自然環境並污染飲水水源，對人體健康造成危害。電鍍廢水中的重金屬可藉由化學混凝法來加以去除，將混凝劑加入電鍍廢水中使無法沉降之微小膠體物質(重金屬)產生凝聚作用以形成膠羽，在混凝過程中可由於膠羽之吸附及電性中和等作用而除去重金屬，待靜置一段時間後，膠羽會沉澱形成污泥，將污泥移除後便可達到去除電鍍廢水中的重金屬的目的。由於電鍍製程中之鍍件材質及使用藥劑的不同，致使廢水中污染物特性差異頗大，不易作比較。故本篇研究採用經濟部工業局所屬之工業污染防治技術服務團所提供之資料，選取在一般電鍍廢水中最常存在之重金屬及其濃度配製模擬電鍍廢水，並利用多元氯化鋁(polyaluminum chloride)、硫酸鐵(ferric sulfate)、石灰(lime)三種混凝劑及高分子助凝劑PA-322 (主成分為hydrolyzed polyacrylamide)來進行杯瓶試驗(jar test)，以找出最佳操作條件。由實驗結果得知，當水樣之pH值調整為11，硫酸鐵加藥量0.5 g時，重金屬去除率可達到100 %，處理後上澄液之pH值接近中性，為此次研究中最理想的處理結果。

Electroplating industry is a branch of metal surface treatment industry, which can improve the surface luster and erosion resistance of electroplate to increase its value. But the wastewater discharge from electroplating process usually contains a large quantity of toxic heavy metals such as Cu, Cr, Pb, Fe, Ni, Zn, etc. If we discharge the wastewater without proper treatment, these heavy metals will do damage to the natural environment and pollute the drinking water source and endanger our health. The heavy metals in electroplating industrial wastewater can be removed by chemical coagulation. Adding coagulant into electroplating industrial wastewater can make tiny colloidal particles (heavy metals) aggregate to form large flocs. In coagulation process, the heavy metals can be removed by adsorption and charge neutralization of flocs. We will achieve our objective of removing these heavy metals by settling for a period of time, for the flocs settle to form sludge and then they are removed.Because the characteristics and concentrations of heavy metals in electroplating industrial wastewater depend on the electroplating materials and on used chemicals in electroplating producing process, it is hard to compare each other. So we prepare the simulate electroplating industrial wastewater in laboratory to make the results significant, the information of main components and their concentrations of heavy metals in electroplating industrial wastewater are supported by industrial pollution control corporation (IPCC). We choose the maximum concentration values of heavy metals that often exist in electroplating industrial wastewater to prepare simulate electroplating industrial wastewater.In this work, we use three kinds of coagulants: polyaluminum chloride (PAC), ferric sulfate, lime and PA-322 flocculant (main ingredient-hydrolyzed polyacrylamide) to remove heavy metals in electroplating industrial wastewater by chemical coagulation with jar test to find the optimal operating conditions. From the experimental results, we concluded that when we add 0.5 g ferric sulfate into the sample solution whose pH value has been adjusted to pH = 11, the removal efficiency of each heavy metal can achieve 100 % and the pH value of supernatant is near neutrality. These are the best results obtained in this research.