河南省某設備制造有限公司  酸洗磷化廢水處理工程案例

一 工程概況

工程名稱：河南省某設備制造有限公司

工程性質：酸洗磷化廢水處理工程

工程范圍：污水處理站1米內的所有內容，包括設備的供貨、指導調試。

酸洗廢水是為了清除金屬表面氧化物，采用硫酸、硝酸、鹽酸、氫氟酸及磷酸等酸進行酸洗法處理時而產生的廢水。廢水多來源于鋼鐵廠或電鍍廠，pH值一般在1.5以下(游離酸0.5-2%)，呈強酸性，采用中和法對廢水進行處理，常采用的中和劑有石灰、白云石及氧化鎂、阻滯分離法。

鋼鐵工業硫酸洗液處理工藝主要有中和法、硫酸鐵鹽法、有機溶液萃取法、滲析法、離子交換法等方法。后面三種方法尚處于試驗研究階段，工業應用較多的是硫酸鐵鹽法生產硫酸亞鐵、聚合鐵及顏料等產品。

對酸洗廢水酸性的處理，實際化學清洗廢水中含重金屬離子較多，也應對重金屬離子進行妥善處理。重金屬離子的處理方法有氫氧化物沉淀法、硫化物沉淀法、氧化還原法和離子交換法等，其中以氫氧化物沉淀法使用較普遍，成本低。

為去除酸洗廢液中的銅、鐵等污染離子，向酸洗廢液中加入液體工業氫氧化鈉、純堿、石灰等，利用壓縮空氣攪動混合，同時可使亞鐵離子氧化，在鐵離子的催化下，聯氨也可分解。調節溶液pH值在10以上的合適范圍，鐵、銅等重金屬離子可與氫氧根離子反應生成難溶于水的金屬氫氧化物沉淀。

此時銅離子將以氫氧化銅的形式沉淀，剩余銅離子的理論含量<0.1mg/L，可滿足排放標難;三價鉻離子的氫氧化物是兩性氫氧化物，它會溶于過量的堿中，所以加堿后溶液pH值應控制在8~9左右。廢液調節溶液pH值后經過靜置沉淀，可將大部分重金屬離子去除，再用酸中和至pH值為9以下排放，如果輔以過濾手段，則去除效果更好。為了防止氫氧化銅部分溶解，排放液pH值不宜低于8。

對于含Cr6+的酸洗廢水常用加亞硫酸氫鈉等還原劑的方法使其轉變成Cr3+, 還原反應在pH9.2時氫氧化鉻會再溶解。

利用薄層分析的原理，廢酸液進入設備裝置，填料將酸截留，廢酸液變成廢液，廢液中的物質被填料阻滯，分別依次排除設備，可根據技術需求截取，用反洗水先淋填料，從設備中流出再生酸。不同的酸液要用不同的填料。

濟寧天通是一家水處理設備生產和銷售集一體的公司，公司擁有高尖端的技術人才，擁有高素質的工作團隊，可以及時地為客戶提供完善的售后服務。我公司主要產品：水處理設備，污水處理設備、廢水處理設備、工業污水設備、農業廢水設備、雨水凈水設備、醫院污水設備、鋼廠廢水設備、屠宰場廢水設備、食品廠廢水處理設備等多種設備，可根據要求專業定制水處理設備。

The case of acid washing and phosphating wastewater treatment project of a equipment manufacturing co., LTD in henan province

Project overview

Project name: henan province equipment manufacturing co. LTD

Engineering properties: acid - washing phosphating wastewater treatment works

Project scope: all contents within 1 meter of sewage treatment station, including equipment supply and guidance debugging.

The acid washing wastewater is to remove the metal surface oxides, and use acid, nitric acid, hydrochloric acid, hydrofluoric acid and phosphoric acid to treat the waste water. Waste water from steel mill or electroplating factory, the pH is in commonly 1.5 the following (0.5-2% free acid), a strong acid, neutralization method to deal with waste water, often using neutralizer of limestone, dolomite and magnesium oxide, block separation process.

The treatment process of sulfuric acid in iron and steel industry mainly includes neutralization method, sulfuric acid salt method, organic solution extraction method, dialysis method, ion exchange method and so on. The latter three methods are still in the experimental research stage, and the industrial application is mainly the production of ferrous sulfate, iron and pigment and other products.

In the treatment of acid washing wastewater, the actual chemical cleaning wastewater contains more heavy metal ions and the heavy metal ions should be treated properly. The treatment of heavy metal ions is composed of hydroxide precipitation method, sulfide precipitation method, REDOX method and ion exchange method, etc., and the use of hydroxide precipitation method is more common and the cost is low.

To remove the pollution such as copper, iron ion in the pickling waste liquor, to add liquid industrial pickling waste liquor caustic soda, soda ash, lime, etc., using compressed air agitation mix, can make the ferrous ion oxidation at the same time, under the catalysis of ferric ion, hydrazine decomposition. The pH value of the adjustment solution is in the appropriate range of 10 or more, and heavy metal ions such as iron and copper can react with hydroxide ions to produce hydroxide precipitation that is difficult to dissolve in water.

The copper ion will be precipitated in the form of copper hydroxide, and the theoretical content of remaining copper ions is < 0.1mg/L, which can meet the difficulty of the emission standard. Trivalent chromium-ion hydroxide is a bisexual hydroxide, which is soluble in excess alkali, so the pH of the solution should be controlled at about 8~ 9. Waste liquid after incubation precipitation after adjusting the solution pH value, can remove most of the heavy metal ions, acid neutralization with below pH value of 9 emissions, if supplemented by filtering, removing effect is better. In order to prevent the partial dissolution of the copper hydroxide, the pH value of the discharge liquid should not be less than 8.

For the acid washed wastewater containing Cr6 +, it is used to convert it to Cr3+ and the reduction reaction will dissolve in pH9.2.

By using the principle of thin layer analysis, the waste acid into the equipment, packing will intercept, acid waste acid into liquid waste, the substances in the waste liquor is filler block, respectively, in turn, ruled out equipment, according to the technical requirements capture, first with backwashing water spray packing, equipment from the regenerated acid. Different acids have different fillings.

Jining day pass is a set of water treatment equipment production and sales of the company, the company has sophisticated technology talented person, has a high quality work team, can provide customers with perfect after-sales service in a timely manner. My company main products: water treatment equipment, sewage treatment equipment, wastewater treatment, industrial wastewater, agricultural wastewater, rain water purification equipment, hospital sewage equipment, steel plant waste water equipment, slaughterhouse wastewater treatment equipment, food factory waste water treatment equipment and other equipment, can professional custom according to the water treatment equipment.