文档介绍：Study on scale inhibition performance by calcined
hydrotalcite

Xiaoli Tian, Nairui Liu, Yu Sha
School of Engine and Energy
Northwestern Polytechnical University
Xi’an, China
1985tianxiaoli@, Lnrme@ nwpu.

Abstract—Mg3Al Layered Double Hydroxides (Mg3Al-LDH) and temperature should not exceed 60℃ and it is not suitable for
calcined Mg3Al layered double hydroxides (Mg3Al-CLDH) are large-scale industrial production.
prepared. According to the gas field in northern Shaanxi water
quality analysis results, this kind of wastewater is simulated in Mg3Al Layered Double Hydroxides (Mg3Al-LDH) is a

the laboratory, this paper studies on removal rate of easily posite interlaced with positive charges and anions
[3] 2+ 3+ n-
scaling carbonate anion by Mg3Al-CLDH. For carbonate anion , expressed as [Mg1-x Alx (OH)2](A )x/n·mH2O, among
solution with concentration of 100mg/L, the removal rate of which x represents the mol ratio of Al/(Mg+Al), An- represents
carbonate anion could be over 59% by addition of Mg3Al- the packed anions of -n valence, and m represents the number
CLDH after 4h reaction at 20℃, and pH=10~12, but the removal of crystal water. The layer of its positive charges is similar to
2+
rate of 100mg/L carbonate anion by Mg3Al-CLDH after four the octahedral structure of brucite with Al support, and Mg is
times recycling may still be %, so the removal rate may in the center of the octahedron. Owing to replacement of Mg2+
3+
reach up to 90% after multiple times recycling use of Mg3Al- by part of Al , the host layer has positive charges which are
CLDH. Mg3Al-CLDH has the characteristics of eco-friendliness, balanced out by the interlayered anions. The interlayered space
reusability, low cost and so on, so calcined hydrotalcite is an ideal is occupied by anions and water molecules. All kinds of anions
material that is used in wastewater scale inhibition in the oil and
may intercalate into the inter