Effect of fouling resistance in heat exchanger and the crystal form of CaCO3 in hard circulating cooling water with electrostatic field and alternating current electric field

Abstract

The effect of high voltage electrostatic field and high voltage alternating current electric field on the heat exchanger surface fouling under the condition of hard water was investigated. The Ca2+ concentration in two water conditions was 12 mmol/L. The Mg2+ concentration was 10 mmol/L and 12 mmol/L respectively. The concentration changed with the Mg2+ concentration. X-ray diffraction and Scanning electron microscope results confirmed that the main crystal phases of the scale samples consist of calcite and aragonite. The high voltage electrostatic treatment can promote scale growth under both water quality conditions. However, the high voltage alternating current electric field treatment shows a good scale inhibition effect under both water quality conditions, and the scale inhibition effect is best when both Ca2+ and Mg2+ concentrations are 12 mmol/L, and the average scale inhibition rate reaches 47.58%. When the calcite content of the scale sample is significantly higher than that of aragonite, Mg2+ affects the growth and solubility of crystals. On the other hand, the high voltage alternating current electric field treatment can effectively extend the fouling induction period of the adherent scale on the heat exchanger surface, which is favorable for heat exchanger fouling.

Analisis Performa Persentase Stripping dan Efisiensi Panas Stripper (DA-101) pada Unit Sintesa Urea PUSRI-II B

“…Sesuai dengan penjelasan dari [1] yang menyatakan bahwa scale dapat timbul karena adanya potens terjadinya pengendapan dari adanya konsentrasi larutan carbamate yang terlalu tinggi pada temperatur tertentu. Penelitian [16] serta [17] menunjukkan kesepakatan bahwa scale bersifat merugikan karena scale menjadi lapisan penghambat yang mempunyai daya hantar panas rendah sehingga dapat mengurangi efisiensi dari alat-alat industri. Kinerja Stripper (DA-101) ditinjau dari efisiensi panas diketahui bahwa kalor yang berpindah antara fluida dalam tube dan shell masih sangat baik.…”

Physicochemical Characteristics and the Scale Inhibition Effect of Air Nanobubbles (A-NBs) in a Circulating Cooling Water System

“…In recent years, physical scale inhibition methods, including the magnetic field scale inhibition method, electric field scale inhibition method, and ultrasonic scale inhibition method, have received wide attention because of their long service life, low costs, and zero pollution. Although the above-mentioned physical scale inhibition methods are environmentally friendly and are limited by the scale inhibition mechanism, they are only suitable for low-hardness water treatment processes .…”

“…In recent years, physical scale inhibition methods, including the magnetic field scale inhibition method, electric field scale inhibition method, and ultrasonic scale inhibition method, have received wide attention because of their long service life, low costs, and zero pollution. Although the above-mentioned physical scale inhibition methods are environmentally friendly and are limited by the scale inhibition mechanism, they are only suitable for low-hardness water treatment processes . When water hardness is high, the scale inhibition effect of existing physical scale inhibition methods drops sharply, although the combination of two or more methods can achieve a better scale inhibition effect at a larger investment cost. , Therefore, it is necessary to develop a new economical and efficient green scale inhibition method for a circulating cooling water system.…”

“…Although the above-mentioned physical scale inhibition methods are environmentally friendly and are limited by the scale inhibition mechanism, they are only suitable for low-hardness water treatment processes. 9 When water hardness is high, the scale inhibition effect of existing physical scale inhibition methods drops sharply, although the combination of two or more methods can achieve a better scale inhibition effect at a larger investment cost. 8,10 Therefore, it is necessary to develop a new economical and efficient green scale inhibition method for a circulating cooling water system.…”

Research on scale inhibition law of high sulfate mine water based on response surface methodology

“…The pH value of mine water is often low, accompanied by a large number of ferrous ions, which increases the difficulty of its treatment. The water quality characteristics of mine water with high calcium and magnesium ions, high carbonate ions, and high sulfate ions will cause it to be very easy to scale in the circulating cooling system, where the formation of sulfate scale is difficult to be removed by conventional methods 1–8 …”