Water is one of the most important utility of any project. The main areas of water requirement are Process Water, Cooling Water, Domestic or General Purpose Water and Drinking Water. In designing water systems for industries, following points must be taken into consideration.
1.Water Resource Mapping
2. Water Lifting Shifting
3. Water Storage and Distrbution Enineering
4. Pumping Station and Electrical Pannels
5. Water Treatment and Purification
6. Distribution Piping Design
7. Effluent Collection and Drainage
8. Effluent Treatment
9. Water Recycling
Water Resource Mapping
This is a quantitative & qualitative analysis of existing as well as proposed water sources which are available.
After understanding the total requirement of water in terms of quantity required per day or per hour and the quality of water required, specially in case of PROCESS water, the water resource mapping is done. For example the resource could be an open well / bore well / River / Dam etc. The water sample collection, testing / chemical analysis, strength / yeild analysis etc are main steps of this exercise. Another important aspect is feasibility and cost analysis of lifting and treatment of water from available sources.
2. Water Lifting / Shifting
When the source of water is away from the site where it is finally required, the water has to be lifted from a bore–well / Jack well or Open well and it has to be pumped to the site where the storage tanks are built. This requires the design of pumps, proper flow rate as well as Head calculations as per desired quantity of water.
In case of souce being far away from the destination, water lifting and shifting has to be designed keeping in mind the contour, water levels for different seasons, primary treatment needed. Pumping stations will be designed accordingly.
Water Storage and Distribution
Water storage Tanks ( above ground / Under ground or Overhead ) are designed as per daily requirement, general predicted availability of source, Pressure requirements inside the factory etc. Various chambers inside the main storage tank are designed as per the distribution requirements. Eg. – Raw Water, Treated Water, Fire Water Drinking Water etc. The pump sets are deigned for various consumption requirements for each chamber of the tank and the required pressure at the usage points. While designing any storage and distribution system, future expansion and flexibility to accommodate fluctuations in demand or supply has to be considered.
Pumping Station & Electrical Control Panels
Pumping Stations or Pump House designing along with electrical control panels is one important aspect of water distribution. The Automation as well as safety requirements are main considerations while designing the Pump House and related Automation Panels.
Water Treatment And Purification
Raw water quality, Final Expected quality of water for the usage point, Running cost of various treatment methods and Ease of operations as well as maintenance are main factors taken into consideration while designing any treatment plant. The basis of any water treatment plant is always feasibility of operations and process requirements where it has to be used.
Media Filtration, Softening, Reverse Osmosis, De–Mineralization, Chemical Disinfection, UV Purification etc are various methods which are used to get the desired quality of water from the available sources.
Distribution Piping Design
This covers pipe lines from the storage tanks to the usage points. The pressure and flow rate requirements along with the peak and continuous demands are considered for piping design. The shortest path with minimum pressure losses in bending, water hammers etc. are taken as design basis.
Effluent Collection and Drainage
The effluent or waste water coming from various machines / operations is to be collected and taken to the ETP. This is a very important requirement which is often ignored while designing the flooring. Under ground piping / Trenches are to be designed as per contour of the land and water has to reach the ETP by gravity.
Effluent is generally collected in a equalization tank which is under ground. The rest of the plant can be above ground or half underground as per the levels available. The treatment is designed from the nature of effluents generated, chemicals used in processes and the estimated daily collection of waste water and pollution control norms. In many new industries ZERO DISCHARGE or complete recycling of water in ETP is a major concern and the space, cost, operations feasibility are very important design factors.
Water recycling after ETP or STP is done in almost all projects now. This is basically done to reduce the overall intake / consumption of water, and also to conserve water as a precious resource. The domestic or general purpose used water with very basic treatment can be used for gardening or toilet flushing. With refined processes it can be used for any process or can be even added to raw water.