Nickel inventory

Some authors have claimed that KOH-NH3 primary coolant chemistry as applied in the WER reactors leads to lower radiation dose rates on the primary system. In the course of their work at the DIDO Water Loop, Large and Wood-wark (1989) investigated this type of primary coolant chemistry under conditions which were comparable to those applied in the experiments with LiOH chemistry. Their results showed comparatively low corrosion product concentrations in the coolant, suspended solids as well as dissolved species the radioactivity buildup on the loop surfaces, however, was on the same order as that experienced with coordinated Li/B chemistry. From these findings the authors concluded that the comparatively low radiation dose rates which are reported from VVER plants are not due to the type of coolant chemistry employed, but to the absence of Stellite and Inconel in the primary circuit, i. e. to low cobalt and nickel inventories of the materials in contact with the primary coolant. 

AH nickel compounds are considered as suspected carcinogens and are Hsted in the EPA and TSCA s toxic substances inventory. LD q (mice iv) for... 

Inventory of nickel in various global environmental compartments... 

Table 6.4 Inventory of Nickel in Various Global Environmental Compartments...

Table 4-1 lists the facilities that produced, imported, processed, or used nickel and its compounds in 1993 according to reports made to the EPA under the requirements of Section 313 of the Emergency Planning and Community Right-to-Know Act of 1986, which were subsequently published in the Toxic Chemical Release Inventory (TRI) (TRI93 1995). Companies were required to report if they produced, imported, or processed 75,000 pounds of nickel and its compounds or used >10,000 pounds. Also included in Table 4-1 is the maximum amount of nickel and its compounds that these facilities had on site and whether nickel was produced, processed, or used by the facility. 

Several economic evaluations of the nickel process as compared with the rhodium process, made by Halcon and by independent consultants, agreed that there is savings of about Iq/lb of acetic acid in favor of the nickel process. The difference is derived essentially from utility savings due to the higher reaction rate, simplified separation and lower water concentration. The nickel process consumes less than half the energy needed for the rhodium-catalyzed process. The catalyst inventory, and the equipment needed for its recovery contribute to the higher cost of production in the rhodium case. 

The utilization of nickel level on catalyst as an age marker is based on previous evidence that nickel deposits uniformly on the circulating catalyst inventory, independent of catalyst activity (1.2). In contrast to the case for nickel, vanadium... 

The characterization of petroleum cracking catalysts, with which a third of the world s crude oil is processed, presents a formidable analytical challenge. The catalyst particles are in the form of microspheres of 60-70 micron average diameter which are themselves composites of up to five different micron and submicron sized phases. In refinery operation the catalysts are poisoned by trace concentrations of nickel, vanadium and other contaminant metals. Due to the replacement of a small portion of equilibrium catalyst each day (generally around 1% of the total reactor inventory) the catalyst particles in a reactor exist as a mixture of differing particle ages, poisoning levels and activities. 

CONSENSUS REPORTS NTP 10th Report on Carcinogens. Reported in EPA TSCA Inventory. Nickel and its compounds are on the Community Right-To-Know List. SAFETY PROFILE Low toxicity by ingestion. Confirmed human carcinogen with experimental mmorigenic data. See also... 

Coastal s production plan during the time period studied, which was July 1989 to July 1990, required the FCCU to make a minimum of 50% vol. cat gasoline. To achieve this when the refinery was not recycling demetallized catalyst required a continual makeup of 15 TPD of fresh catalyst, The refinery used 15 TPD of fresh catalyst between July 1989 and March 1990, which was immediately prior to the DEMET test run. They also used 15 TPD during the period of May 1990 to July 3990. which was the period after the test run. It was necessary for the refinery to maintain a constant calal y st inventory of 450 tons in the cat cracker and as they were adding 15 TPD and losing 3 TPD to their fine particulate col lection systems, it was necessary to withdraw 12 TPD of equilibrium catalyst. This catalyst was disposed of to landfill. The equilibrium catalyst contained 2,000 PPM of nickel and 450 PPM of vanadium. It had a surface area of about 128 nv/gm. 

---