SANDVIK COROMANT COMPANY - Executive Summary
Sandvik Coromant Company receives titanium tetrachloride as a liquid in cylinder containers. This cylinder is received from a supplier and unloaded with a fork lift truck directly into the toxic gas storage room adjacent to the rear of the main building. The block building's storage area has a roof, walls, vehicle and personnel doors, water sprinkler and carbon dioxide (CO2) fire suppression systems, and monitors or sensors for hydrogen chloride (used for titanium tetrachloride releases where airborne moisture creates the hydrogen chloride gas), and hydrogen sulfide. A dike confinement area is also provided in the storage and distribution room. The storage room is nominally ten feet from the perimeter fence and within three hundred feet of the rear guard house. The block building is kept under slightly negative pressure via an exhaust to the process scrubber. |
Gaseous argon, supplied from a cryogenic storage tank of argon and its vaporizer (which is located in the rear parking lot
of the Sandvik Coromant, Fair Lawn, NJ site) is used to inertly pad the titanium tetrachloride cylinder tank. Liquid titanium tetrachloride is forced out of the tank using the argon pad. Pressure is kept below 1 bar (14.5 psig). The rupture disk located on the downstream holding tank is set for 2 bar and exhausts to the scrubber system. Flexible stainless steel or viton hoses will be used to connect the cylinders to the liquid inlet manifolds. The manifold and the titanium tetrachloride piping are made of 316L stainless steel or monel throughout the process. The titanium tetrachloride lines are pressure tested twice per year and detectors are used to detect hydrolysis products (hydrogen chloride) which occur if the titanium tetrachloride is leaked. All lines have welded connections or flanges (at valves) prior to the process storage tank. Swagelock fittings are used at the process evaporator cabinet.
The down stream holding tanks, also known as the "day" tanks, are used to rece
ive the liquid titanium tetrachloride from the supply cylinder tank. There are five "day" tanks which connected in parallel via manifold and valves. These five "day" tanks are used to supply the process trains where pairs of trains are operated in parallel. All tanks are within the main building operating area, which is exhausted to the scrubber system.
The worst case scenario chosen is the instantaneous total failure of the cylinder in the storage area, dropping 1500 pounds of material into the containment dike, this scenario is highly unlikely due to the construction of the cylinder. An analysis using the USEPA RMP*Comp software indicated that the release could travel as far as 0.22 miles (0.35 kilometers) if no controls were in place. Evaporation time would be 11700 minutes and the maximum release rate would be 128 lbs./min. The toxic gas storage room is vented to the scrubber system designed to neutralize any release. The controls on the scrubber system are set to increase t
he exhaust velocity from the toxic gas storage room if the sensors in the room detect a release. The scrubber is maintained at an alkaline pH by the addition of caustic. The system would effectively remove and neutralize the worst case scenario, thereby not allowing any titanium tetrachloride to enter the atmosphere outside of the room or to reach the environment.
An alternative scenario analyzed is the loss of the .75" feed line from the tank under feeding conditions of 1 bar pressure. The RMP*Comp software calculated the release rate to be approximately 1.93 lbs./sec. If uncontrolled, the release would travel 0.06 miles (0.1 kilometers). With the design of the scrubber system such that a release is detected, and the scrubber flow from the area increased to 1700 cfm to the alkaline scrubber, there is no release to the outside environment.
Listed below is a summary of the key risk reduction efforts and safety measures employed to minimize the risks of an accidental release of tit
anium tetrachloride from the equipment used in the process. These steps are complimented by the other components of the Risk Management Plan including engineering controls, operating procedures, preventative maintenance, training and emergency preparedness. The operations are carefully monitored and controlled by the computerized process control system housed in the control room. The operating control room is maintained at a positive pressure relative to the surrounding operating area. Operating and support personnel are all trained in the procedures they are to follow during startup, shut down, normal and emergency operations. ISO 9001 Certification demonstrates that the procedures, practices and training are properly documented and enforced.
? All titanium chloride areas are secured and only authorized personnel are allowed to enter.
? Titanium tetrachloride is purchased on an inventory control basis such that there is never more than one full and one in use cylinder on site. T
he target inventory point is less than 3020 lbs. on site.
? The supplier shall deliver cylinders directly to the storage room area in order to minimize handling.
? A forklift with a specially designed carrier is used to remove the cylinder from the supplier's truck and place the cylinder in the storage room.
? The storage room is fully enclosed and the materials are stored over a lined collection pit to capture any releases.
? The room is maintained under a negative pressure by venting the area to a scrubber system.
? A monitoring system is employed to detect any release in the room. The system triggers an alarm and increases the exhaust rate from the room to the scrubber.
All piping is stainless steel and hoses are viton or stainless steel. Sandvik has a written Emergency Response Plan the plan that includes specific actions to be taken in response to accidental releases of a regulated substance. The plan includes procedures for informing the public and local agencies responsible fo
r responding to accidental releases and emergency health care. A copy of the plan, which was last revised March 10, 1998 by an outside consulting firm. There is annual training of personnel coordinated with the Fair Lawn Police and Fire Departments.
There have been no titanium tetrachloride accidents in the last five years.