PROCESS: What are the challenges when it comes to water management?
DR RAO: The challenge always is to design solutions that are cost effective. Our onsite engineers understand our customers’ processes
intimately and the impact of water quality on heat transfer efficiency, asset preservation, quality of products and production. This allows us to design ‘fit for use’ solutions where we match the required level of treatment to the requirements of the process receiving the recycled water. This reduces the overall cost of treatment. Use of modelling tools helps us design these solutions, and perform ‘what if’ analysis well before customers decide to put concrete on the ground, which mitigates risk.
The Water Energy Nexus – Why Water and Energy are One
PROCESS: Water and energy are intricately intertwined in industrial plants. Please tell us how organizations can reduce their utility and water consumption and develop environmental and energy saving strategies.
DR RAO: We call it the water-energy nexus and it is an area of big focus these days. Water is used extensively in the production of energy, whether hydraulic, nuclear or fossilfuel driven, or in the production of oil and natural gas. On the other hand, energy is used extensively in the processing and transportation of water. Water also happens to be the most widely used medium of energy transfer in the industry because of its beneficial heat-transfer properties and abundance. Non-optimal water-treatment practices result in issues related to corrosion, scale and deposit formation, or microbiological growth, which in turn impact energy transfer and water use efficiency. Therefore, good management of water often translates into efficient management of energy.
On the subject of water and energy optimization, there are some common themes that apply to all industries, whether they are refineries processing crude oil or hotels managing HVAC load. Cooling systems are often the biggest users of water in any industrial plant. Improper operation of a cooling system can result in non-optimal cycles of concentration (that is, non-optimal efficiency of the use of water), resulting in fouling of heat exchangers either from inorganic salt deposits, microbiological activity or corrosion by-products. Use of best practices in cooling treatment can help minimize water and energy leakage in these systems.
In a boiler, inefficient fireside operation can result in energy losses. Improper condensate treatment can result in corrosion and dumping of condensate streams with good quality and high calorific content. Use of fireside chemical and mechanical treatment and best practices in feedwater, condensate, and internal treatment can help with water and energy optimization. Often, use of blowdown heat exchangers can be helpful in saving energy.
Similarly, proper operation of a pre-treatment system can help minimize fouling in an RO system, and the resulting energy impact. Proper wastewater operation can result in optimization of air used in aerobic systems, and in some cases, anaerobic waste treatment can be a net contributor to energy in a plant. The key is to start with a thorough chemical, mechanical and operational audit of the system, and understand all the users and emitters of water and energy.
This article is protected by copyright. You want to use it for your own purpose? Contact us via: support.vogel.de/ (ID: 42488518 / Ex Protection & Safety)