Distillation Desalination Facilities with Mechanical Steam Compression

Function

  • Demineralization and desalination of marine and other natural waters;
  • Producing of desalted feed water for industrial needs and power engineering;
  • Concentrating of industrial effluent flows and solutions;
  • Supply of household, potable and hot water.

Application

Providing water supply for small-sized settlements, hotel complexes and suburban villas.

Use of Distillation Desalination Facilities with Mechanical Steam Compression (DOU-MK) for preparation of feed water for industrial needs and power engineering allows significant reducing of chemicals consumption (sodium chloride, acids and alkali) which generate mineral-polluted effluent flows having a negative impact on the environment.

As an example, see the table wherein technical characteristics of certain distillation desalination facilities with mechanical steam compression equipped with horizontal tubular beams sprayed with water to be desalinated (DOU GP).

Structure of DOU GP

  • Evaporators unit, laminar heat-exchangers, regenerative pre-heaters;
  • High-speed mechanical vacuum steam compressor (MK)*;
  • Starter electric steam generator;
  • Vacuum generating and maintaining device (water ejection unit);
  • Tank equipment;
  • Antiscalant preparation and dosing plant;
  • Scrubbing solution preparation plant for removing scale from the process equipment;
  • Electric pump aggregates, shut-off and control valves, pipelines;
  • System of monitoring and automated control of the technological process.

Operating principle of DOU-MK

The equipment works with use of “heat pump” principle and, unlike in conventional distillation desalination facilities, delivery of heating steam from the external source is not required for operation of DOU-MK, just electric power will be sufficient. The mechanical steam compressor will act as a trim condenser in DOU-MK, so arrangement of water-circulation cycle for cooling of DOU condensers will not be required. Secondary steam from the last evaporator shall be delivered to the steam compressor suction where it is compressed, whereas the steam temperature and pressure will grow, and further on the compressed steam will be delivered to the first evaporator as heating steam.

Advantages of DOU-MK

  • External source of heating steam and water-circulation cycle for cooling of condensers are not required;
  • Continuity of the process and low labour costs;
  • Compactness and low consumption of metal;
  • Possibility of modular construction;
  • Extremely small specific expense of chemicals and materials;
  • Regeneration solutions are not discharged outside (unlike in the case of chemical desalination).
  •  * NOTE — Facilities can be equipped with steam compressors designed by FGUP “MMPP Salyut”, Moscow.

Technical Specifications:

Parameters

DOU-1/4MK

DOU-4/4MK

DOU-10/4MK

DOU-20/4MK

Nominal capacity per distillate, m3/day

24

100

250

500

Steam volumetric flow rate at evaporator outlet, max., m3/s

0.35

2.3

5.8

11.6

Steam pressure, MPa:

 

 

 

 

in 1st stage

0.035

 

 

 

in 4th stage

0.020

 

 

 

Total salt content of primary water:

 

 

 

 

-marine or ocean

 up to 45 g/l

 

 

 

-other
 

defined by chemical compositions

 

 

 

Specific power consumption, kW*hour/1 ton of distillate

 8—9
 

 

 

 

Concentration of salts in distillate, mg/l

 5…50

 

 

 

Number of stages

4

 

 

 

Weight of evaporator, tons

1.4

16.1

25.3

48.3

Facility dimensions (length×width×height), m

3.5×2.4×3.0
 

8.0×4.2×5.8
 

 14.7×4.2×5.8
 

20.0×4.2×5.8
 

Material design

For distillation of marine waters: heat-exchanging surfaces made of alloy ЛАМШ-77-2-0,05; ВТ1-0; body made of steel 03Х17Н14М3. Can be corrected depending on the type of desalted water.

Number of hours of use per year

8400

 

 

 

Service life, years

25

 

 

 

The Quality Management System of SverdNIIChimmash JSC is certified in accordance with GOST R ISO 9001—2008 (ISO 9001—2008); efficiency of the quality management system is confirmed by international certificates of IQNet and QualityAustria.

Upon Customer’s request, specialists of SverdNIIChimmash JSC will design and ensure manufacture of a similar facility and render technical assistance at the stage of mounting and commissioning. Technical data of DOU-MK can be corrected in accordance with Customer’s terms and requirements.