The High-Technology of Limpidness
Major Technologies & Facilities for Seawater Desalination
Coordinating the plant design, manufacture of the principal machine and engineering construction, providing the seawater distillation solutions and equipment at low cost for users, and realizing the dual-purpose power and water plant, and small-sized MED equipment for vessel and offshore platform.
Integrating the advanced & feasible pretreatment technology, reverse osmosis subject technology, on-line cleaning technology, and advanced manufacturing technology, and providing large and middle-sized reverse osmosis seawater distillation equipment with steady operation at a reasonable price and movable distillation equipment.
2.Technical Characteristics and Advantages of MED
1.Take full usage of waste heat in the power plant (suitable for enterprises with surplus heat source);
2.Strong adaptability and simple pretreatment for the seawater;
3.Effectively prevent corrosion and scaling;
4.Product water conductivity is less than 10μs/cm, can be as boiler feed water or high quality process water through simple treatment;
5.Have a high operating flexibility, load from 100% to 40%;
6.Auto-control and easy maintenance
3.Advantages of RO Technology
Technologies &Facilities in Industrial Water Treatment
Adopting the reverse osmosis,ion exchange or EDI complex technology,and providing the desirable ultra-pure water preparation equipment for such industries as electric power,elecrtonics, pharmacy and chemical engineering.
Adopting the ultrafiltration and reverse osmosis complex technologies to realize the high-purpose reuse of municipal sewage by treatment of the secondary effluent, also called raw water discharged from the sewage treatment palnt.
For the nonbiodegradable industrial wastewater,the revese osmosis and efficient evaporation composite technologies are used to reuse the useful materials,realize the high-quality reuse and reach the zero emission.
1.System Process In Industrial Wastewater Treatment
Zhonghe provides the zero discharge solution for industrial waste water, power plant desulfurization wastewater, reusing oilfield produced waterto boiler, high salinity mine wastewater and other special industrial wastewater treatment.,which uses the evaporation/concentration and crystallization / drying technology as the core， The main process shown in figure 1:
1）Industrial waste water mainly includes the seriously environmental pollution wast water such as the power plant desulfurization wastewater, oilfield produced water and high salinity mine wastewater etc.
2）The unit of pretreatment removes mainly substances in industrial waste water that are harmful to the evaporator operation and treats the feed water by degassing, regulating temperature pH.The process is depended on the analysis of the raw water quality, which including coagulation sedimentation, dissolved air flotation, softening, medium filtration and water oil separator etc.
3）Evaporation and Concentration Unit
a. Multi-effectVertical Tube Falling Film Evaporation System
Multi-effect vertical tube falling film is the traditional process, generally 3 to 5 effects. To the 3 effects system as an example (Figure 2), the boiler steam is supplied to the effect of the highest concentration (third effect) and the waste water in this effect is evaporated to the final concentration and then discharge to the crystallization system to do further crystallization process. Regenerative steam is supplied to the intermediate effect (second effect) as a source of energy, and so on. Finally, the regeneration steam in the first effect is supplied to the main condenser, and then is condensed by the cooling water. The steam jet ejector evacuates the non-condensable gases.
b. Mechanical Vapor Recompression Evaporation
The advantages of the technology of horizontal tube spray falling film MVC vapor compression (Figure 4) are low operation cost, convenient repair, no secondary pollution, good at anti -fouling and small occupation of land etc. Its features are as follows:
Brine goes from shell phase(outside the tube). The tube bundle is horizontal placed which has the advantages like low fouling rate inside tube and good water distribution uniformity etc. Because the thin film evaporation and evaporation surface without water pressure, the evaporation efficiency is higher than the kind of vertical tube falling film. Steam supplied by the compressor goes from the pipe phase. Steam is condensed in tube and the heat is exchanged to the wastewater sprayed to the outside of the pipe. Tube bundles are separated for several sections so that the non-condensable gas can be discharged smoothly which is good for energy saving and the stable and reliable operation. There is enough area and height for liquid / gas separation in the evaporator, further more there is automatic scaling facilities in the fog dispersal system, which can guarantee the long period of evaporation and stable quality of the product water.
4）Crystallization and Drying Unit
Forced circulation steam compression device is the most efficient crystallization system (Figure 6), which is suitable for easy scaling and high viscosity liquid. The main process is that the brine is supplied by the pump from the bottom into the device and mixed up with the circulating brine, and then supplied into the shell and tube heat exchanger by the brine circulating pump, which is reciprocating cycle to achieve continuous crystallization. Small part of brine is evaporated and crystal is produced in the brine. Most of the brine is recycled to the heater and then a small stream of water is pumped to the subsequent dewatering drying equipment, which can make the separation of crystals. Steam after removing impurity by the fog dispersal system and pressured by the compressor releases its latent heat to the brine in the heating pipe. Distilled water can be used as the make-up water of high quality recycling. The crystal product can be reusedsuch as salt, ammonia sulfate etc.