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Float It; T b i i Burn It
Cal M e t a Process Goes Full Scale
Chicago studies flotation process la «concent r o t e sludge solids*», taed them ito w e t corn biarstio*"i process
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CALCIUM METAPHOSPHATE NORMAL SUPERPHOSPHATE
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C h i c a g o sanita*i°n tfspierts Imave
N/SUTIONIAL m o v e d another Water, MBETIhiG Selvage, s t e p c l o s e r t o a n J& Sanitation i n t e g r a t e d process Chemistry t o g e t r i d of t h e city's sevuv/age w i t h no protblem of contamiwuitinjsc air o r w a t e r . AMready p i l o t i n g a w e t s l u d g e c o m b u s t i o n p r o c e s s t o c o n v e r t organic m a t t e r t o c=arbi>E* d i o x i d e asad w a t e r , the>' n e w hftaw c o m e u p w i t h w h a t looks like u p r a c t i c a l m e t h o d for -conc e n t r a t i n g slmidge suspensions to a l i i g h e n o u g h solidls coxa t e n t t o use them for d i r e c t feed fto th«c c o m b u s t i o n unit. E m a n u e l IHurwitz of t h e ! \ I e t i o p o l i t a n Sewage O s t r i c t of G r e a t e r Chicago t o l d t h e DSvisioan o f Water-, Sewage, a n d S a n i t a t i o n C h e m i s t r y thiit he a n d W i l l i a m J. Katz of C h a i n Belt l i a v e f o u n d i n time l a b o r a t o r y tlbat s l u d g e voïids will c o n c e n t r a t e by flotation. T h e y have w o r k e d o u t a p r o c e s s for d o i n g this by ^dissolving i t i r in t h e s l u d g e susj>«eiisio»ri a n d then reducing s y s t e m pressure 1:0 atmosphoaric. T h e Ziintmernaan w e t c o m b u s t i o n p r o c e s s reqwaires a f e e d h a v i n g a fuel v a l u e of a b o u t 4IO0O B.t.u. p e r g a l l o n , H u r w i t z sa\rs. T~o g e t t h i s w i t h sludges t h e y handle in C h i c a g o , h e lmas to conc e n t r a t e s u s p e n s i o n s w h i c h a r e usxially a b o u t V'* solids ito a level of 5 to 6.5Γ/ress u r i z a t i o n ί w h i c h c o n t r o l s . a m o u n t of a i r dissolved). No cheeiicals are n e e d e d , Ihmrwitz finds. L a b datât s h o w t h a t priinuary s l u d g e d o e s best, follovwed b y modified a c t i v a t e d s l u d g e stnd o r d i n a r y activated sludge. Mixtures a r e intermediate- Rec y c l e ratios of iri&out 2 a n d p r e s s u r e s of 4 0 p.s.î. als*o loolc g o o d . 60 C i E W S E P T . 2 2. I 9 50
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POTASH & OTHER SOLID RAW MATERIALS
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\ Pog Mills Here Replace a Single TVA T y p e Reactor, Give Better Liquid Phase Processing
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Outlook Bright for Caî Meta Plant hydrolyzes and ammoniates calcium metaphosphate in high concentration of sulfuric acid
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In recent years, considerable ex-
perimental work has been d o n e using calcium m e t a p h ο s ρ h a te t ο make mixed gran ular fertilizers. O n e difficulty w a s always experienced: T h e reactors u s e d did not tolerate a high e n o u g h liquid p h a s e to r e s u l t in a n e c o n o m i c a l e n d p r o d u c t w i t h a h i g h , w a t e r - s o l u b l e P^O-content. A new process, now used com mercially, o v e r c o m e s this problem a n d yields a r a n g e of f o r m u l a t i o n s , a c c o r d i n g t o J o s e p h L . J e n i s t a , A l b e r t V. M a l o n e . andL L a d d i e J. P i r c o n , C e n t r a l F a r m e r s F e r t i l i z e r , at t h e D i v i s i o n of F e r t i l i z e r a n d Soil C h e m i s t r y . In t h e p r o c e s s , c a l c i u m m e t a p h o s p h a t e a l o n e , or w i t h n o r m a l s u p e r p h o s MEETING Fertilizer & SoU Chemistry
p h a t e to s u p p l y s o m e of t h e Ρ 2 0 Γ ι , is h y d r o l y z e d a n d a m m o n i a t e d in a h i g h c o n c e n t r a t i o n of s u l f u r i c a c i d . Rapid r a t e s of r e a c t i o n a c c o m p a n i e d b y h i g h e n e r g y r e l e a s e r e s u l t in a c o m p a c t , c o n tinuous, self-drying, granulation proc ess. Following considerable research on t h e c h e m i s t r y of c a l c i u m m e t a p h o s p h a t e h y d r o l y s i s in m i n e r a l a c i d s , a 1ton-per-hour pilot plant w a s built. Its s u c c e s s f u l o p e r a t i o n l e d t o t h e first c o m m e r c i a l p l a n t at E a s t St. L o u i s , 111. Output: 20 tons an hour. T h e plant h a s run s i n c e last S e p t e m b e r , a n d t h e p r o c e s s w a s p a t e n t e d last J u n e . • The Process. The commercial s c a l e u n i t is o p e r a t e d b y Illinois F a r m Supply. Three pug mill reactors s e r v e as h y d r o l y z e r , a m m o n i a t o r , a n d granulator. All internal moving p a r t s
