Selection of threshold agents for calcium sulfate scale control on the basis of chemical structure

Sarig, S.; Kahana, F.; Leshem, R.

doi:10.1016/s0011-9164(00)84057-6

Cited by 37 publications

(10 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To reduce scaling propensity in the sugarcane and allied industries, low‐molecular‐weight polymers, e.g. poly(acrylic acid), poly(maleic acid), acrylic–maleic copolymers and polyphosphonic acid inhibit or retard the crystallisation of carbonates,1 sulfates,2–5 oxalates6, 7 and phosphates,8 have been used with mixed successes. In the sugarcane industry, these polymers are not very effective 9.…”

Section: Introductionmentioning

confidence: 99%

Deposition of hydroxyapatite and calcium oxalate dihydrate on a heat exchanger tube

East¹,

Doherty²,

Fellows³

et al. 2011

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

Most studies on the characterisation of deposits on heat exchangers have been based on bulk analysis, neglecting the fine structural features and the compositional profiles of layered deposits. Attempts have been made to fully characterise a fouled stainless steel tube obtained from a quintuple Roberts evaporator of a sugar factory using X-ray diffraction and scanning electron microscopy techniques. The deposit contains three layers at the bottom of the tube and two layers on the other sections and is composed of hydroxyapatite, calcium oxalate dihydrate and an amorphous material. The proportions of these phases varied along the tube height. Energy-dispersive spectroscopy and XRD analysis on the surfaces of the outermost and innermost layers showed that hydroxyapatite was the major phase attached to the tube wall, while calcium oxalate dihydrate (with pits and voids) was the major phase on the juice side. Elemental mapping of the cross-sections of the deposit revealed the presence of a mineral, Si-Mg-Al-Fe-O, which is probably a silicate mineral. Reasons for the defects in the oxalate crystal surfaces, the differences in the crystal size distribution from bottom to the top of the tube and the composite fouling process have been postulated. 

show abstract

Section: Introductionmentioning

confidence: 99%

Deposition of hydroxyapatite and calcium oxalate dihydrate on a heat exchanger tube

East¹,

Doherty²,

Fellows³

et al. 2011

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

show abstract

“…In experiments by Sarig et al [117] to compare the effects of polyvinyl sulfonate (PVS) and polyglutamic acid (PGA) on the precipitation of calcium sulfate dihydrate and hemihydrate, tabular crystals of calcium sulfate dihydrate were deposited from solution A, which contained 0.01 M Ca(NO 3 ) 2 and 0.01 M Na 2 SO 4 at 45 C. Although the presence of PVS makes the deposits thicker than those grown without additive, it does not change their shapes; whereas, PGA causes a remarkable change in the crystal habit but keeps the same crystallographic form. Robust thick hexagonal rods of CaSO 4 $ 1 / 2 H 2 O appear when PGA is present, which seem to be compact and hard instead of the small rounded flakes with dendritic overgrowths of calcium sulfate dihydrate crystals [117]. There is a sponge-like mass of minute crystallites covering the deformed hemihydrate.…”

Section: Effects Of Additives On Scale Morphologymentioning

confidence: 95%

“…Macromolecular additives also have different inhibitory capability; for example, PVS has only slight effect on the precipitation of calcium sulfate from natural seawater (increasing the induction period by 1.5 min and reducing the precipitation by just 7%), while PGA increases the induction period to over 1 h and completely retards the precipitation of calcium sulfate in synthetic seawater at the evaporation ratio of 7.5 and by 77% in natural seawater at 8.2 evaporation ratio [117]. An investigation by Smith and Alexander [149] on many polyacids, PAM, polyphosphates, and poly-4-vinylpyridine showed that the anionic polyelectrolytes are the most active inhibitors for gypsum, PAM is less effective and polycationic additives have no effect at all when used at trace quantities.…”

Section: Chemical Structurementioning

confidence: 99%

Mechanisms of Scale Formation and Inhibition

Hoang

2015

Mineral Scales and Deposits

View full text Add to dashboard Cite

“…Çekirdek oluşumu, kristal büyümesi ve kristal morfolojisi ile boyutu katkı maddeleri sayesinde kolayca değiştirilebilmektedir [3]. Ürün kalitesi ve kristalizasyon parametrelerini etkilemek için katkı maddeleri kullanılmaktadır [4]. Biyomineralizasyon sayesinde organik doku matrisi inorganik kristalleri kontrol etmektedir.…”

Section: Introductionunclassified

Kalsiyum Oksalat Kristalizasyonunun Engellenmesi Üzerine Nar (Punica granatum L) Suyunun Etkisi: Bir Optimizasyon Çalışması

Akın

Ökmen

Alkan

et al. 2019

Bitlis Eren Üniversitesi Fen Bilimleri Dergisi

View full text Add to dashboard Cite

Öz Ürolitiyazis, idrar yollarının herhangi bir bölümünde taş oluşması veya taş bulunması durumu olarak açıklanmaktadır. İdrar taşlarının sık sık tekrarlandığı bilinmektedir ve tıbbi tedavideki ilerlemelere rağmen, bu durumun tedavisinde sonuç veren bir ilaç tedavisi bulunmamaktadır. Böbrek taşları çeşitli organik ve inorganik bileşiklerden oluşur. Kalsiyum oksalat monohidrat, (COM), böbrek taşlarının ana bileşenidir. Bununla birlikte, böbrek taşlarının oluşum mekanizmaları iyi anlaşılmamıştır. Bu bağlamda, çekirdeklenme, kristal büyümesi ve oluşan COM kristallerinin bir araya gelmesi gibi birkaç varsayım vardır. Bu nedenle çalışmalar yürütülürken doğal ve sentetik katkı maddelerinin kalsiyum oksalat (CaC2O4) kristalizasyonu üzerine etkilerinin araştırılması şeklinde pek çok çalışma ile karşılaşılmaktadır. Bu çalışmada nar suyunun CaC2O4 kristalizasyonu üzerine engelleme etkisi araştırılmıştır. Laboratuvar ortamında belirlenmiş faktörler ışığında CaC2O4 kristalizasyon sürecinin nar suyu tarafından engellenmesi Taguchi ortogonal deneysel tasarımı uygulanarak araştırılmıştır. Çalışmalar sonucunda nar suyunun CaC2O4 kristalizasyonu üzerine yavaşlatma ve geciktirme etkisi olduğu görülmektedir.

show abstract

Selection of threshold agents for calcium sulfate scale control on the basis of chemical structure

Cited by 37 publications

References 8 publications

Deposition of hydroxyapatite and calcium oxalate dihydrate on a heat exchanger tube

Deposition of hydroxyapatite and calcium oxalate dihydrate on a heat exchanger tube

Mechanisms of Scale Formation and Inhibition

Kalsiyum Oksalat Kristalizasyonunun Engellenmesi Üzerine Nar (Punica granatum L) Suyunun Etkisi: Bir Optimizasyon Çalışması

Contact Info

Product

Resources

About