Description of the System:
System for improvement of water and creation of ultra-pure water, in which there are 14 chemical and physical stages. This system facilitates a great deal of flexibility in relation to the quality of the source water, and in addition ensures complete stability in the resulting water product.
The Vishay Company, which was founded in 1962, is considered to be the largest manufacturer in the world of passive electronic components, and the main manufacturer of semi-conductors. The company employs about 20,000 people throughout the world, in 70 plants dispersed among 22 countries. In Israel there are about 4,000 employees.
In the semi-conductor manufacturing process, the water is used for washing during the manufacturing process and therefore is required to be of high quality: electrical resistance of 18.2 mega ohms. Objectives:
- Production of water of the required quality, under production conditions and processes, while the water product remains at a constant stability, 24 hours a day, 365 days a year.
- A high level of utilization in the process without wastewaters that could pollute the environment.
- Compliance with regulatory conditions.
- Reduction of the quantities of chemicals stored at the plant and intended for water treatment.
- Installation of the system within a smaller location than commonly accepted for systems of this nature.
Flow Rate of the Water Product: 150,000 cubic meters annually
Uniqueness: the system serves as a central axis of the manufacturing process of the semi-conductors
Added Value Provided to the Customer:
- Characterization and placement of a wide variety of technologies for a single efficient and stable process.
- Creation and construction of a single system that comprises the functionality of two passes, First Pass and Second Pass.
- Savings in the operation costs by reduction of the stocking of chemicals and storage area.
Description of the Process:
The system enables a drastic change in the quality of the water. On one side of the system a mixture of surface water with various textures including a large amount of pollutants flows in, and on the other side of the system water of the highest possible quality that can be produced by water improvement procedures (18 mega ohms) is produced.
The preliminary treatment is based on an automatic filtration system, intended to stabilize SDI values in the water prior to their entry into the membrane systems.
The membrane system, by means of a double pass creates conditions of purification and removal of minerals as it works by using an osmosis device of one or two passes. The membrane system produces water without salts at a level of conductivity of about 2 micro Siemens.
The EDI system produces water at a level of resistance of about 16 mega ohms. This system includes a temperature balancing system as well as pressure monitoring for the purpose of supplying water for the final ion-free stage. The final touches to the water quality are performed by the following actions: reduction of the TOC level by a UV system on a wavelength of 185 nm; an ion-removing system based on Nuclear Grade ion-exchange resins; purification and filtration by sub-micron filters with an absolute degree of filtration and by a UV unit at a wavelength of 254 nm.
A combination of all of these ensures the stability of the product at the required level.