The scale formation and solubility of the reclaimed water reused in recycling cooling system

2011 ◽  
Author(s):  
Guanhua Yue ◽  
Hongyun Zou ◽  
Lili Feng ◽  
Yajun Zhang
Keyword(s):  
Cooling System ◽  
Reclaimed Water ◽  
Scale Formation

The Influences of Main Ingredients of the Reclaimed Water on Calcium Carbonate Scale in Recycling Cooling System

2011 ◽  
Vol 393-395 ◽  
pp. 1554-1557
Author(s):  
Guan Hua Yue ◽  
Li Min Shang ◽  
Li Ping Wang ◽  
Li Li Feng
Keyword(s):  
Cooling System ◽  
Thermal Power ◽  
Reclaimed Water ◽  
Chloride Ion ◽  
Sulfate Ion ◽  
Scale Inhibition ◽  
Soluble Silica ◽  
Anions And Cations ◽  
Main Components ◽  
Calcium Carbonate Scale

The main risk of reclaimed water reused in industry is to control fouling. The main ingredients in reclaimed water form the chemical scale which is one of the main components of the fouling in the recycling cooling system. The main chemical scale of reclaimed water is carbonate scale (calcite). In this paper, by using the actual reclaimed water which reused as make-up water in Beijing Thermal Power Plant to simulate the 4 times concentrate ratio recycling water to study the influence of main ingredients of reclaimed water such as pH，soluble silica, the most content of anions and cations on carbonate scale. The experimental results show that pH, soluble silica, calcium ion and alkalinity have greater influence on scale inhibition, but magnesium ion, chloride ion and sulfate ion have smaller influence on scale inhibition.

Scale Inhibitors Used in Cooling System and the Determination of their Dispersing Power

2012 ◽  
Vol 170-173 ◽  
pp. 2718-2722
Author(s):  
Xiao Lu Qi ◽  
Guan Hua Yue ◽  
Jing Shen
Keyword(s):  
Calcium Carbonate ◽  
Lattice Distortion ◽  
Cooling System ◽  
Scale Formation ◽  
Experimental Basis ◽  
Key Technologies ◽  
Effective Technology

One of the key technologies in recycling cooling system is controlling scale formation, practices have shown that the chemical antisacle method of using inhibitors is the most economic and effective technology. Inhibitors can antisacle by their properties of complexation, lattice distortion and dispersity. In this paper, an easy and effective method of calcium carbonate powder to test their dispersing power is put forward. And by this, the dispersing power of 7 low molecular inhibitors and 9 polymer inhibitors have been determined and ordered, this will provide a significant experimental basis for screening inhibitors.

scholarly journals Methods of monitoring water conditions of the circulatory cooling system of a combined heat and power plant

Vestnik IGEU ◽  
2019 ◽  
pp. 14-21
Author(s):  
V.V. Kozlovsky ◽  
A.B. Larin
Keyword(s):  
Water Chemistry ◽  
Cooling System ◽  
Bacterial Count ◽  
Scale Formation ◽  
Total Bacterial Count ◽  
Cooling Systems ◽  
Circulating Water ◽  
Water Conditions ◽  
Stabilization Factor ◽  
Heat Exchange Equipment

A common method of preventing scale formation on the internal surfaces of the condenser and heat ex-changers at thermal power plants with circulatory cooling systems (CCS) is correctional treatment with an addition of sulfuric acid for acidifying make-up water and reducing its alkalinity and the alkalinity of recycled water and dosing of oxyethylidenediphosphonic acid (OEDFK) for preventing scale deposit formation. The existing method of correction treatment does not provide the necessary degree of heat exchange equipment protection from scale formation. With this method of cleaning, it is impossible to completely remove deposits from the surface of the tubes to «pure» metal; the concentration of sulfates in the purge water often exceeds the permissible level. Improving the efficiency of water conditions requires developing a calculation method and creating a pilot plant for monitoring scale formation and corrosion through estimation of water chemistry directly in industrial conditions, which is the goal of this work. The circulating water corrosivity was studied on a stand that simulates the operation of circulatory cooling systems. The coil simulating water movement inside heat exchangers contained carbon steel and brass corrosion rate witness plates. A quantitative assessment of the biological contamination of the circulating water of the cooling system of the CCPP ПГУ-450 MW was carried out using total bacterial count (TBC) express tests. To estimate the probability of carbonate salt deposition in heat exchange equipment, we have proposed a method of calculating the existing values of the stabilization factor (calcium transport). The proposed method has been used to estimate the state of water chemistry of the circulatory cooling system of CHP PGU-450 MW. Calculations confirmed by the data of chemical analyzes of water and deposits have shown increased deposit mass values on the control samples (stabilization factor less than 85 %), including biological ones (the total bacterial count exceeded the permissible value by over 104 CFU / ml). The circulating water corrosivity also increased, and the corrosion rate of steel st. 20 exceeded the standard values (0,1 mm / year). The developed technique can be effectively used for analyzing the state of both the existing water conditions of circulatory cooling systems, and any other (alternative) water chemistry directly in industrial conditions of operation of a certain CCPP.

The Scale and Antiscale Laws of the Main Ions in the Recycling Cooling System Used Reclaimed Water

2013 ◽  
Vol 448-453 ◽  
pp. 1141-1146
Author(s):  
Guan Hua Yue ◽  
Man Zhang ◽  
Yuan Ling Zhao
Keyword(s):  
Cooling System ◽  
Negative Impact ◽  
Reclaimed Water ◽  
Experimental Results ◽  
Scale Inhibition ◽  
Positive Effect

In recycling cooling system used reclaimed water, the main ions of the reclaimed water must form chemical scales with the increase of temperature and concentrate ratio , In order to control the formation of scale, we must control the fouling ion in the reclaimed water.In this paper the influence laws of Ca2+, Mg2+, HCO3- , SO42-, PO43-, NH4+ , NO2- , NO3- in reclaimed water on the scale inhibition are researched . The experimental results show that Ca2+, HCO3- , PO43- in reclaimed water have negative impact on scale and antiscale ;Mg2+ and NH4+ have positive effect on scale and antiscale;and SO42-, NO2- , NO3- hardly affected on scale and antiscale.

Research on the Formation and Preventive Measure of Scale in the Cooling System of HVDC Converter Valve

2011 ◽  
Vol 354-355 ◽  
pp. 1157-1160 ◽  
Author(s):  
Yi Hua Qian ◽  
Yong Yan Zhou ◽  
Chong Wu Xu
Keyword(s):  
Cooling System ◽  
Power Grid ◽  
Preventive Measure ◽  
Scale Formation ◽  
Valve Tray ◽  
Safe Operation ◽  
Aluminum Compounds

The valve tray is the main device to support the voltage of HVDC. The faults of the cooling system of HVDC converter valve greatly impact the safe operation of the power grid. About 66% of the all faults are valve cold system stoppages which are caused by the electrode scaling, electrode gasket corrosion and the pipes clogged by scale which can lead to poor cooling. The scale was verified to be Aluminum compounds. This paper analyzes the cause of scale formation and offers some proposals to prevent scale formation.

A High Angle, Double Tilting Cold Stage for the AEI EM7

1974 ◽  
Vol 32 ◽  
pp. 450-451
Author(s):  
P.R. Swann ◽  
A.E. Lloyd
Keyword(s):  
Habit Plane ◽  
Temperature Control ◽  
Tilt Angle ◽  
Cooling System ◽  
Thermal Drift ◽  
High Angle ◽  
Cold Stage ◽  
High Degree ◽  
Better Than

Figure 1 shows the design of a specimen stage used for the in situ observation of phase transformations in the temperature range between ambient and −160°C. The design has the following features a high degree of specimen stability during tilting linear tilt actuation about two orthogonal axes for accurate control of tilt angle read-out high angle tilt range for stereo work and habit plane determination simple, robust construction temperature control of better than ±0.5°C minimum thermal drift and transmission of vibration from the cooling system.

A conduction-cooled stage for high-resolution Cryo-SEM

1992 ◽  
Vol 50 (2) ◽  
pp. 1282-1283
Author(s):  
John G. Sheehan
Keyword(s):  
High Resolution ◽  
Liquid Nitrogen ◽  
Mechanical Stability ◽  
Cooling System ◽  
Cold Trap ◽  
Nitrogen Gas ◽  
Particulate Suspensions ◽  
Advantages And Disadvantages ◽  
Convection Cooling ◽  
Styrene Butadiene

The goal is to examine with high resolution cryo-SEM aqueous particulate suspensions used in coatings for printable paper. A metal-coating chamber for cryo-preparation of such suspensions was described previously. Here, a new conduction-cooling system for the stage and cold-trap in an SEM specimen chamber is described. Its advantages and disadvantages are compared to a convection-cooling system made by Hexland (model CT1000A) and its mechanical stability is demonstrated by examining a sample of styrene-butadiene latex.In recent high resolution cryo-SEM, some stages are cooled by conduction, others by convection. In the latter, heat is convected from the specimen stage by cold nitrogen gas from a liquid-nitrogen cooled evaporative heat exchanger. The advantage is the fast cooling: the Hexland CT1000A cools the stage from ambient temperature to 88 K in about 20 min. However it consumes huge amounts of liquid-nitrogen and nitrogen gas: about 1 ℓ/h of liquid-nitrogen and 400 gm/h of nitrogen gas. Its liquid-nitrogen vessel must be re-filled at least every 40 min.

Sign in / Sign up

Export Citation Format

Share Document