Energy Conservation Project
Energy Conservation Potential Identified in Industries
- Carried out Process Study of Sulfuric Acid Plant of Hindustan Zinc, Debari Plant for taping energy conservation potential using Variable Frequency Drive instead of IGV control for Flow and Furnace Draft Control.
- Carried Energy Audit of Steel Rolling Plant at Kalol, Gujarat. The main source of energy was Hot Furnace (1100-1200 °C) based on RNLG. The KRA (Key Result Area) of energy audit was temperature optimization and reduction of losses through hot flue gases. During audit, the temperature pattern was observed and also loading and unloading pattern observed and found out that the temperature frequently overshoots the prescribed range and the loading pattern was not uniform, so stream lining of whole process suggested based on the forecasting of market requirement. This was implemented and significant reduction in gas bill is observed with very low investment.
- During same study we also observed that the Cold Rolling Machine Spindles are not aligned and causing power loss, so we suggested alignment of Spindles to tap loss of energy.
- Carried out energy audit of MCPL, Jarod, Vadodara: The plant was basically imported from USA and was designed to run at 60 Hz. During audit, we found out that whole plant was run at underrated capacity and also was running inefficiently. The new system is proposed and implementation is under progress.
- The detail audit of GPPL, Kalol. The plant has 1 MW Gas based power plant. The company has VCR based chillers for their process requirement. During study we observed that the exhaust flue gas temperature from Gas Engine is in the range of 580 to 650 °C. THe VAM machine suggestion is implemented there and exhaust flue gas temperature is brought down to as low as 120 °C and 60 TR of refrigeration capacity is added from waste heat recovery.
- Energy Study at CPRI, Trivendrum: The combustion efficiency of boiler was very low and Stoichiometric A/F ratio was not maintained as a result of which the excess air present during combustion was carrying away additional heat in atmosphere. The system and operation was studied thoroughly and PLC based system designed and implemented to control fuel and primary air flow to maintain excess O2 in control.
- Apollo Dye Chem Industries, Ahmedabad: The HAG was very inefficient and consuming excessive energy. The hot air duct was passing through the plant from HAG to DRYER. The line was insulated using lagging but this was not enough and the surface temperature was observed 40 °C lesser that the duct line temperature. The temperature profile was studied and suggested additional lagging. Also, the draft was controlled through damper control, which was suggested to replace with VFD. The implementation paid back money in just 11 months.
- Aegis Chemicals, Vatva, Gujarat: The dust filter was installed to capture the micro particles of blue dye. This filter bag was purging using compressed air at an regular interval. This system was wasting compressed air during light load condition and was consuming very high blower power during high load condition due to choking of filter. The new system based on feedback of differential pressure across filter bag was suggested. The suggested system is so effective that pay back was realized in a month time.
- Shilpa Impex Limited, Kalol, Gujarat: The annealing furnace loading pattern was very irregular and it had to continually light up in wait of material from upcoming process. The complete process was studied and just scheduling of plant helped customer to achieve significant saving by reducing no load time of annealing furnace.
- During Audit of Rubber Plant, Chennai, it was observed that the superheat temperature of R12 Gas from evaporator was much above the prescribed range and it was running around 15 to 18 °C. This was putting extra stress on refrigerant compressor, so the feedback based control scheme for throttle valve was suggested to avoid loss of energy. Also the water temperature based condenser is suggested.
- During audit of Videocon, Aurangabad, it was observed that the main hydraulic motors of injection molding machines are operated continuously at 50HZ, while process pattern of the machine was varying. It is suggested to use VFD with PLC card to optimize the process time and to get the energy saving. Suggestion was accepted by management and during demonstration energy saving identified up to 23%.
- In same company, chiller plant was used for cooling requirement of injection molding machine. It was observed that the temperature difference of the chilled water was only 2.0 °C. It is suggested to provide the insulation on supply/return line to maintain the chilled water temperature.
- GPL, Surat: Two 330 TR chiller systems are installed. This system has two chiller compressors. 1. 220 TR and 2. 170 TR. Log book data observed and from past record, identified that the one system having problem in refrigeration gas line and consuming higher energy compared to other system. It is suggested to operate second unit which have lower energy consumption and other unit should be operated after rectification of problem.
- In same company, air handling unit system is used for the process area cooling. One AHU is used for Quench area, which having surround temperature of 40 °C to 45 °C. And this hot air is re-circulated through the AHU system. It is suggested to put one thermostatic controller in return line and suggested to use atmospheric air when temperature of plant air is higher. This has avoided extra refrigeration load on chiller plant.
- BSCL, Kalol: This unit having waste water treatment plant. Waste water is sent to Pollution plant of GIDC after being processed. For the transferring purpose of waste water, two pumps were used. During site visit, it was suggested to eliminate the use of one pump and suggested to use overhead tank. As the head requirement was not so much.
- In many industries, it is observed blower-motor system and compressor-motor system are operated with inefficient V-belt drive system. It was suggested to replace existing v-belt system with energy efficient flat belt system. And majority client achieved the energy saving through this replacement.
- In many industries, it is observed that the chiller systems are having hot well and cold well system. In these hot well and cold well systems, more pumps required to circulate the chilled water. It was suggested to remove hot well & cold well system and use only one pumping circuit after some modification. By doing this, company achieved noticeable energy saving by eliminating one pumping circuit.
- In many industries, identified inefficient pumping operations and suggested to replace with energy efficient pump system. Payback period was less than 1 years, for some of the pump system.
- Cadila Healthcare, Ahmedabad: The installed overrated blower in AHU system was pivotal point for many problems including higher current kick, energy loss in damper control system etc… The problem identified and implemented with PLC based drive control system. The payback was realized in seven moths only and better controllability is an added advantage.
- STL, Ahmedabad: 25TPH FBC Boiler was in operation, when studied, found in efficient. We studied
thoroughly the operation and found following points relevant with higher energy losses, first,
the higher percentage of un-burnt carbon losses due to the bed velocity was estimated higher than
the prescribed range. The bag filter system is suggested for capturing un-burnt carbon loss of
around 5%. And second, the moisture content in powdered coal was high due to improper storage and
other vendor related reasons. The proper coal storage and moisture removal using solar based HAS is
suggested. After implementation, the coal consumption was reduced by appreciable amount. Also the
improved lagging of steam distribution line and replacement of faulty steam traps also played vital
role in achieving savings.
Contact for any query:
JIGNESH PATEL - ASST. MANAGER