Galvanizing Engineering هندسة الجلفنة

  Galvanizing Flux : Wet or Dry Method  The advantages and disadvantages of the dry and wet methods are still disputed, which is better? But the choice depends to a large extent on the quality of the products for  galvanizing. The main advantages of the dry method • Higher production capacity. • Reducing the output Dross. • Lower operating cost. The main disadvantages of the dry method: • Needs a bath (more space) • Needs heating (energy consumption) • Needs continuous treatment or shut down to adjust the concentration of the tank and iron content  • These equipments need continuous and periodic maintenance.  The main advantages of the wet method: • Providing space and equipment (there is no bath or heating). • A layer of Flux on the surface of the zinc kettle gives a better cleaning of the products surface  especially when there were errors in the previous stages. • In general, it gives less thickness of zinc, especially if the product is pulled through the flux layer, as it is abrasi

الفلكس  الطريقة الرطبة او الجافة    إن محاسن ومساوئ طريقتي الفلكس الجافة والرطبة مازالت موضع خلاف ، أيهما أفضل ؟ ولكن الخيار يعتمد إلى حد كبير على نوعية المنتجات المراد جلفنتها .   أهم محاسن الطريقة الجافة : ·        طاقة إنتاجية أعلى . ·        تقليل الدروس الناتج . ·        كلفة تشغيلية أقل . أهم مساوئ الطريقة الجافة : ·        تحتاج لحوض ( حيز كبير ) ·        تحتاج للتسخين (استهلاك طاقة ) ·        تحتاج لمعالجة مستمرة او توقف لضبط تركيز الحوض ومعالجة الحديد ·        تحتاج هذه التجهيزات لصيانة مستمرة ودورية .    أهم محاسن الطريقة الرطبة :   ·        توفير في المكان والمعدات ( لا يوجد حوض أو تسخين ). ·        طبقة الفلكس على سطح حوض الزنك تعطي تنظيف أفضل لسطح المنتج وخاصة عندما تكون هناك أخطاء في المراحل السابقة .   ·        بشكل عام تعطي سماكة أقل من الزنك وخاصة إذا تم سحب المنتج من خلال طبقة الفلكس حيث أنها تقوم بفعل الكشط. ·        تزيد من مجال السلامة عندما تكون المنتجات غير مجففة حيث تقلل من تطاير الزنك . ·        كمية الآش قد تكون أقل .

Observations:  1-Reducing material consumption (zinc)  2- Reducing energy consumption   3- Increasing quality of production. Description : New research has developed a novel, METALLIC FLUX COMPUND, to reduce ash formation, theoretical, this compound will increase ash formation to 50%     Environmental feasibility:     1-    Reducing waste ash 2-    Reducing consumption of energy Economic feasibility: The total quantity of ash = 203.1 ton / y    in 2003   The zinc in ash = 203.1*0.7 = 142.17 The price of ash is considered as 55% zinc That mean = 0.41* 203.1 = 83.271 The loses = 142.17 – 83.271 = 58.9 ton saving / year The price of zinc per ton = 1253 Saving = 58.9 *1253 =73801.7 $  / year    Technical and organization consideration: The additives  depend on the amount of production 250 gr \ ton production 10976.632 *0.25 = 2744.158 kg The price of gold flux = 4938.168 $ The price of total quantity for one year = 2.7442 *4938.168 = 13551.32 $. Abou

                                                                         1-        6 HCl + Fe 2 O 3 ----- 2 FeCl 3 + 3 H 2 O  2-             Fe + HCl  -------- Fe Cl 2 + H 2   The main concentration of pickling tank is 16% wt/ wt . The performance of the tank can't be effective when it reaches 5  wt/ wt . At this point the iron content is 150 gr / lit . it means you have  ore or iron mine . There is more than one option to treat this consumed acid : ·         Acid Regeneration : it can be used on or off line by using special type of resins in order to get rid of iron then concentrate  it to reach crystal stage as FeCl 3 and it is necessary to keep Fe content within 10 gr/ lit to reduce dipping time in pickling or acid tank . the second option to treat the consumed acid off line by evaporation or treat it with sulfuric acid as below 3 H 2 SO 4 + 2 FeCl 3 ------ 6 HCl +   Fe 2 ( SO 4 ) 3   H 2 SO 4 +  FeCl 2 ------  2 HCl +   Fe SO 4 The value of ferric sulfa

      A-       degreasant   1-    Degreasing: It is  used to remove organic substances or contamination   , the concentration of this material usually  10% wt/wt from tap water  2-    Actually 7.5% has been used in decreasing tank the, the process take place without problem in production 3-    The temperature of the tank is  75 c, there are neutral , alkaline and acidic degreaser .  4-    The dipping time is the same . 5 -    The method of check the concentration is necessary  to improve performance  and to  control .     B- pickling additive   1-     This additive is used as: a- inhibitor agent b- wetting gent c- anti – vaporization agent 2-     1.4% of the concentrated acid is added to the pickling tank from the pickling additive   3-     The use of the pickling additive has taken place with out any problems 4-  they are  harm ful    in case of producing new substances from consumed acid , and same for water treatment ( almost contain heavy  metals  and

     There are two factors to be considered : 1 - The iron for galvanizing is a product and not galvanized for the purpose of maintenance. 2- If the option to choose the metal exists, it is desirable to choose iron  that gives us a high quality product within the basic criteria, including: 1- The chemical composition of the metal, especially the content of silicon, carbon and phosphorous .... etc . 2- The surface must be free of organic pollutants (dyes, paints, polymers, bitumen). 3-   No  high corrosion or  pores in the metal surfaces . 4- The thickness of the iron should be consistent and  no significant differences. 5- The design  of products should allow draining of molten zinc.