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Rochem Q2 results show start of transition
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S u r e fire s u c c e s s for h o l l o w fibre ceramic
R o c h e m Q2 results show start of transition
A n i n o r g a n i c h o l l o w fibre m o d u l e c l a i m e d to o v e r c o m e two of t h e t r a d i t i o n a l d r a w b a c k s of ceramics -- expensive production methods and a lower p a c k i n g d e n s i t y - - is u n d e r d e v e l o p m e n t . The t r a n s v e r s e flow m e m b r a n e m o d u l e , m a d e from a silicon n i t r i d e - b a s e d c e r a m i c , is t h e r e s u l t of a j o i n t TNO ( N e t h e r l a n d s O r g a n i s a t i o n for A p p l i e d Scientific Research) and Eindhoven University collaboration. R a t h e r t h a n u s e t h e sol-gel p r o c e s s , w h i c h is complex, t i m e c o n s u m i n g a n d t h e r e f o r e expensive, t h w hollow fibres a r e p r o d u c e d b y e x t r u s i o n of the c e r a m i c p o w d e r s in a n o r g a n i c m a t r i x . T h e m a n u a c t u r i n g p r o c e s s h a s four s t a g e s . T h e c e r a m i c m a t e r i a l is c o m b i n e d w i t h a p o l y m e r i c binder, a n d t h e n e x t r u d e d to form t h e hollow fibre p r e c u r s o r s . The c e r a m i c m e m b r a n e is f o r m e d b y r e m o v i n g t h e o r g a n i c c o m p o u n d b y h e a t t r e a t m e n t , a t t e m p e r a t u r e s in e x c e s s of 1200°C. F i n a l l y t h e hollow fibres a r e c o a t e d with a g a s selective a l u m i n a top-layer. E a c h of t h e fibres h a s a d i a m e t e r of l e s s t h a n 1 m m a n d a wall t h i c k n e s s of 0.1 m m , w h i c h m a k e s the unit compact. The researchers claim the m e m b r a n e s u r f a c e a r e a offered b y t h e n e w m o d u l e is a n o r d e r of m a g n i t u d e h i g h e r (on a u n i t v o l u m e basis) than anything achievable with conventional ceramic filters. Its t r a n s v e r s e c o n f i g u r a t i o n m e a n s t h a t m a s s t r a n s f e r is i m p r o v e d c o m p a r e d to o r d i n a r y crossflow filtration. T h e lower flow velocity to a c h i e v e t h e s a m e flux, a n d t h e r e f o r e lower p r e s s u r e d r o p a l o n g t h e m o d u l e l e a d s to e n e r g y c o n s u m p t i o n u p to five t i m e s lower t h a n for a c r o s s f l o w c o n f i g u r a t i o n . The i m p r o v e d m a s s t r a n s f e r a l s o l e a d s to a low l o u l i n g t e n d e n c y , allowing s l u r r i e s u p to a t l e a s t 20 wt% to be a c c o m m o d a t e d . All of w h i c h m a k e s its p e r f o r m a n c e attractive compared with tubular systems. Now t h a t t h e p r o j e c t t e a m h a s s u c c e e d e d in developing a multifunctional ceramic membrane unit t h a t is r e s i l i e n t e n o u g h to w i t h s t a n d t h e r i g o u r s of s t e a m c l e a n i n g , it is l o o k i n g into t h e p o s s i b i l i t y of a d a p t i n g t h e t e c h n o l o g y for even m o r e d e m a n d i n g a p p l i c a t i o n s . T h e first p r i o r i t y is a c e r a m i c m e m b r a n e m o d u l e for s e p a r a t i n g g a s e s a t h i g h t e m p e r a t u r e . T h e t e a m is l o o k i n g for p a r t n e r s in t h e food, ( p e t r o ) c h e m i c a l a n d g a l v a n i c i n d u s t r i e s to p a r t i c i p a t e in t h e f u t u r e d e v e l o p m e n t of t h e t r a n s v e r s a l c e r a m i c hollow fibre m o d u l e for s e l e c t e d a p p l i c a t i o n s . For f u r t h e r information, contact: TNO Infodesk, PO Box 6050, 2600 JA Delft, The Netherlands. Tel: +31 15 269 6969;fax: +31 15 261 2403.
R o c h e m E n v i r o n m e n t a l , Inc. h a s r e p o r t e d a n e t loss of $251 345 (S0.01 p e r s h a r e ) in t h e s e c o n d q u a r t e r , w h i c h e n d e d 31 M a r c h , 1996. This c o m p a r e s w i t h a loss of $ 3 6 3 3 1 1 ( S 0 . 0 2 p e r s h a r e ) for t h e s a m e p e r i o d in 1995. F o r t h e six m o n t h s e n d i n g 31 M a r c h 1996, R o c h e m l o s t $511 520, c o m p a r e d w i t h a l o s s of $ 7 3 4 867 in t h e first h a l f of 1995. Six m o n t h r e v e n u e s d e c l i n e d to $ 5 4 6 6 6 8 from 8 9 4 8 205, R o c h e m P r e s i d e n t a n d CEO E r i c k N e u m a n b e l i e v e s t h a t t h e p a s t q u a r t e r m a r k s t h e b e g i n n i n g of t h e c o m p a n y ' s t r a n s i t i o n to a f o c u s on t h e i n d u s t r i a l a n d p r o c e s s w a s t e w a t e r m a r k e t s . He cites t h e m o s t s i g n i f i c a n t e x a m p l e of t h i s a s t h e C h e v r o n ' s c o n t r a c t a w a r d e d after t h e q u a r t e r h a d e n d e d . R o c h e m will treat waste water produced during catalyst changes at the P a s c a g o u l a refinery. T h e f o u r - y e a r e x t e n s i o n is w o r t h a million d o l l a r s a n n u a l l y . For f u r t h e r information, contact: Rochem Environmental, Inc., 610 Milby Street, Houston, TX 77003, USA. Tel: +1 713 224 7626;fax: +1 713 224 7627.
2
Power plant solves silica p r o b l e m s w i t h RO Reverse o s m o s i s t e c h n o l o g y is offering a m o r e effective a l t e r n a t i v e to d e m i n e r a l i s a t i o n for b o i l e r feed treatment. When a demineralisation system was u n a b l e to m e t silica s p e c i f i c a t i o n s for b o i l e r feedwater, a power plant added an Osmonics reverse osmosis (RO) m a c h i n e to i m p r o v e t h e overall o p e r a t i o n of its w a t e r t r e a t m e n t s y s t e m . The O S M O RO m a c h i n e , o p e r a t i n g a h e a d of a n e x i s t i n g d e m i n e r a l i s e r s y s t e m , r e d u c e d TOC b y 50% a n d TDS levels b y 98% in a d d i t i o n to e l i m i n a t i n g t h e p l a n t ' s s i l i c a p r o b l e m s , Initially t h e p o w e r p l a n t c o n s i d e r e d u s i n g a d d i t i o n a l d e m i n e r a l i s a t i o n ; however, field t e s t i n g indicated that such as system could not meet the silica limits specified b y t h e boiler m a n u f a c t u r e r . F u r t h e r o n - s i t e t e s t i n g d e m o n s t r a t e d t h a t RO r e m o v e d the colloidal s i l i c a t h a t d e m i n e r a l i s a t i o n s y s t e m s h a d b e e n u n a b l e to remove. T h e RO m a c h i n e a l s o i m p r o v e d boiler o p e r a t i o n b y s i g n i f i c a n t l y lowering TOC levels a n d w a t e r c o n d u c t i v i t y . In a d d i t i o n , t h e low-TDS RO p e r m e a t e i n c r e a s e d t h e s e r v i c e r u n s of
M e m b r a n e T e c h n o l o g y No. 74
S u r e fire s u c c e s s for h o l l o w fibre ceramic
R o c h e m Q2 results show start of transition
A n i n o r g a n i c h o l l o w fibre m o d u l e c l a i m e d to o v e r c o m e two of t h e t r a d i t i o n a l d r a w b a c k s of ceramics -- expensive production methods and a lower p a c k i n g d e n s i t y - - is u n d e r d e v e l o p m e n t . The t r a n s v e r s e flow m e m b r a n e m o d u l e , m a d e from a silicon n i t r i d e - b a s e d c e r a m i c , is t h e r e s u l t of a j o i n t TNO ( N e t h e r l a n d s O r g a n i s a t i o n for A p p l i e d Scientific Research) and Eindhoven University collaboration. R a t h e r t h a n u s e t h e sol-gel p r o c e s s , w h i c h is complex, t i m e c o n s u m i n g a n d t h e r e f o r e expensive, t h w hollow fibres a r e p r o d u c e d b y e x t r u s i o n of the c e r a m i c p o w d e r s in a n o r g a n i c m a t r i x . T h e m a n u a c t u r i n g p r o c e s s h a s four s t a g e s . T h e c e r a m i c m a t e r i a l is c o m b i n e d w i t h a p o l y m e r i c binder, a n d t h e n e x t r u d e d to form t h e hollow fibre p r e c u r s o r s . The c e r a m i c m e m b r a n e is f o r m e d b y r e m o v i n g t h e o r g a n i c c o m p o u n d b y h e a t t r e a t m e n t , a t t e m p e r a t u r e s in e x c e s s of 1200°C. F i n a l l y t h e hollow fibres a r e c o a t e d with a g a s selective a l u m i n a top-layer. E a c h of t h e fibres h a s a d i a m e t e r of l e s s t h a n 1 m m a n d a wall t h i c k n e s s of 0.1 m m , w h i c h m a k e s the unit compact. The researchers claim the m e m b r a n e s u r f a c e a r e a offered b y t h e n e w m o d u l e is a n o r d e r of m a g n i t u d e h i g h e r (on a u n i t v o l u m e basis) than anything achievable with conventional ceramic filters. Its t r a n s v e r s e c o n f i g u r a t i o n m e a n s t h a t m a s s t r a n s f e r is i m p r o v e d c o m p a r e d to o r d i n a r y crossflow filtration. T h e lower flow velocity to a c h i e v e t h e s a m e flux, a n d t h e r e f o r e lower p r e s s u r e d r o p a l o n g t h e m o d u l e l e a d s to e n e r g y c o n s u m p t i o n u p to five t i m e s lower t h a n for a c r o s s f l o w c o n f i g u r a t i o n . The i m p r o v e d m a s s t r a n s f e r a l s o l e a d s to a low l o u l i n g t e n d e n c y , allowing s l u r r i e s u p to a t l e a s t 20 wt% to be a c c o m m o d a t e d . All of w h i c h m a k e s its p e r f o r m a n c e attractive compared with tubular systems. Now t h a t t h e p r o j e c t t e a m h a s s u c c e e d e d in developing a multifunctional ceramic membrane unit t h a t is r e s i l i e n t e n o u g h to w i t h s t a n d t h e r i g o u r s of s t e a m c l e a n i n g , it is l o o k i n g into t h e p o s s i b i l i t y of a d a p t i n g t h e t e c h n o l o g y for even m o r e d e m a n d i n g a p p l i c a t i o n s . T h e first p r i o r i t y is a c e r a m i c m e m b r a n e m o d u l e for s e p a r a t i n g g a s e s a t h i g h t e m p e r a t u r e . T h e t e a m is l o o k i n g for p a r t n e r s in t h e food, ( p e t r o ) c h e m i c a l a n d g a l v a n i c i n d u s t r i e s to p a r t i c i p a t e in t h e f u t u r e d e v e l o p m e n t of t h e t r a n s v e r s a l c e r a m i c hollow fibre m o d u l e for s e l e c t e d a p p l i c a t i o n s . For f u r t h e r information, contact: TNO Infodesk, PO Box 6050, 2600 JA Delft, The Netherlands. Tel: +31 15 269 6969;fax: +31 15 261 2403.
R o c h e m E n v i r o n m e n t a l , Inc. h a s r e p o r t e d a n e t loss of $251 345 (S0.01 p e r s h a r e ) in t h e s e c o n d q u a r t e r , w h i c h e n d e d 31 M a r c h , 1996. This c o m p a r e s w i t h a loss of $ 3 6 3 3 1 1 ( S 0 . 0 2 p e r s h a r e ) for t h e s a m e p e r i o d in 1995. F o r t h e six m o n t h s e n d i n g 31 M a r c h 1996, R o c h e m l o s t $511 520, c o m p a r e d w i t h a l o s s of $ 7 3 4 867 in t h e first h a l f of 1995. Six m o n t h r e v e n u e s d e c l i n e d to $ 5 4 6 6 6 8 from 8 9 4 8 205, R o c h e m P r e s i d e n t a n d CEO E r i c k N e u m a n b e l i e v e s t h a t t h e p a s t q u a r t e r m a r k s t h e b e g i n n i n g of t h e c o m p a n y ' s t r a n s i t i o n to a f o c u s on t h e i n d u s t r i a l a n d p r o c e s s w a s t e w a t e r m a r k e t s . He cites t h e m o s t s i g n i f i c a n t e x a m p l e of t h i s a s t h e C h e v r o n ' s c o n t r a c t a w a r d e d after t h e q u a r t e r h a d e n d e d . R o c h e m will treat waste water produced during catalyst changes at the P a s c a g o u l a refinery. T h e f o u r - y e a r e x t e n s i o n is w o r t h a million d o l l a r s a n n u a l l y . For f u r t h e r information, contact: Rochem Environmental, Inc., 610 Milby Street, Houston, TX 77003, USA. Tel: +1 713 224 7626;fax: +1 713 224 7627.
2
Power plant solves silica p r o b l e m s w i t h RO Reverse o s m o s i s t e c h n o l o g y is offering a m o r e effective a l t e r n a t i v e to d e m i n e r a l i s a t i o n for b o i l e r feed treatment. When a demineralisation system was u n a b l e to m e t silica s p e c i f i c a t i o n s for b o i l e r feedwater, a power plant added an Osmonics reverse osmosis (RO) m a c h i n e to i m p r o v e t h e overall o p e r a t i o n of its w a t e r t r e a t m e n t s y s t e m . The O S M O RO m a c h i n e , o p e r a t i n g a h e a d of a n e x i s t i n g d e m i n e r a l i s e r s y s t e m , r e d u c e d TOC b y 50% a n d TDS levels b y 98% in a d d i t i o n to e l i m i n a t i n g t h e p l a n t ' s s i l i c a p r o b l e m s , Initially t h e p o w e r p l a n t c o n s i d e r e d u s i n g a d d i t i o n a l d e m i n e r a l i s a t i o n ; however, field t e s t i n g indicated that such as system could not meet the silica limits specified b y t h e boiler m a n u f a c t u r e r . F u r t h e r o n - s i t e t e s t i n g d e m o n s t r a t e d t h a t RO r e m o v e d the colloidal s i l i c a t h a t d e m i n e r a l i s a t i o n s y s t e m s h a d b e e n u n a b l e to remove. T h e RO m a c h i n e a l s o i m p r o v e d boiler o p e r a t i o n b y s i g n i f i c a n t l y lowering TOC levels a n d w a t e r c o n d u c t i v i t y . In a d d i t i o n , t h e low-TDS RO p e r m e a t e i n c r e a s e d t h e s e r v i c e r u n s of
M e m b r a n e T e c h n o l o g y No. 74