Indian Farmers Fertilizers Cooperative Limited (IFFCO) has an existing Ammonia and Urea Plant at Kalol, Gandhinagar, Gujarat, which is located on the Ahmedabad-Mehsana State Highway, at about 18 km from Gandhinagar, capital of Gujarat. Major products produced at IFFCO Ltd., are Ammonia (1100TPD) and Urea (1650TPD).
M/s Indian Farmers Fertilizers Cooperative Limited (IFFCO) has entrusted iFluids engineering to carry out the Detailed Engineering for Suitable Pressurization and Ammonia neutralization system to avoid the ingress of Ammonia gas and contaminated air inside the Urea Control Room Building.
The objective of this proposal is to carry out the Detailed Engineering is,
- To deliver Positive pressurization inside Urea Control building.
- To provide Ammonia neutralization system.
- Study of integrity of urea control room and analyze the air leakage points, suggestion to arrest the leakage points.
- Recommend the suitable pressurizing system/any alternative for urea control room to avoid ammonia gas entering from atmosphere.
INTRODUCTION ABOUT HVAC SYSTEM
- The urea control building consists of urea instrument panel room & Package AC room & AHU Room in ground floor and Urea control room, Engineering station room & Pantry in first floor.
- Three numbers of 16.5 TR packaged ac units are installed in HVAC plant room for urea control building air-conditioning purpose.
- The building has already routed with Supply and Return air ducts.
OVERVIEW OF DETAILED ENGINEERING PROPOSAL
- To avoid ammonia contents, present in atmosphere entering into the building through doors and any other openings, we proposed 6 Air Lock rooms (4 in Ground Floor & 2 in First Floor) wherever doors available, for maintaining positive pressure inside the building.
- We insisted to provide a Dry Scrubber instead of proposing Wet Scrubber as wet scrubber has more disadvantages particularly in health.
- Dry Scrubber is connected before the Double Skin Filter Unit and Blower as the atmospheric air enters dry scrubber first and hence ammonia present in atmospheric air gets neutralized, then passed through ducts to all air lock rooms and pantry.
- As proposed to Dry Scrubber, we have designed the duct routings all over the Air Lock rooms.
- In each Air Lock Rooms, we proposed Fusible Fire Dampers in case of emergency fire in nearby rooms.
- Each Air Lock Rooms were proposed to have Volume Control Damper, to attain the specified pressure.
- Every Air Lock Rooms and pantry contains Pressure Relief Dampers, based on the Air flow rate (CFM) inside the room.
- Based on the area of the building, a total of 2300 CFM air flow is provided inside the air lock rooms to maintain 40 – 50 Pa pressure.
OVERVIEW OF EXECUTION
- Civil Work – To close all openings like windows, wall cutouts, cracks and holes.
- Civil Work – To construct all Airlock rooms in Ground floor and First floor.
- Civil Work – To build Pedestal for equipment’s to be located in terrace floor.
- Structural Work – To construct Sheet Roofing Structure to cover the equipment’s located in terrace.
- HVAC Work – To Locate all Equipment’s interconnected in terrace with ducts.
- HVAC Work – To route ducts for Fresh Air Flow to all Airlock Rooms.
- HVAC Work – To position Fire dampers and Pressure Relief Dampers.
- Electrical Work – To interconnect all equipment’s with control panel.
| WET SCRUBBER | DRY SCRUBBER |
| Wet Scrubber can neutralize ammonia content up to 75% to 80% effectively. | Dry scrubber can neutralize ammonia content up to 99.9% for 2.5 PPM and 99.8% for 5000 PPM. |
| Sulphuric acid is used as the neutralizing chemical to neutralize ammonia contents. | Carbon Activated media is used as neutralizing agent. |
| Using Sulphuric acid as neutralizing chemical, toxic fumes will be generated and thus it is not advisable for in healing. | No Toxic contents will be traced using carbon media. |
| As Sulphuric acid is corrosive in nature, it can affect ducts and other electrical terms. | Carbon media does not have Corrosive nature. |
| While using Wet scrubber, Chemical Dosing pumps, pH Dosing pumps connecting pipes, valves and instruments will be in addition for the process. | While using Dry Scrubber, we only have Blowers, Ducts and Filter for full operation. |
| The rate of adsorption of ammonia is less. | The rate of adsorption is high. |
