Inventory state

U.S. Environmental Protection Agency. 1996b. Toxics Release Inventory State Fact Sheets. EPA 745-F-98-00a, EPA, Washington, D.C. 

Eq. (6.19) represents the amount of on-time procurement for raw material i, u( t), which is influenced by the company procurement plan Uj(t) and a random variable i(t). Eq. (6.20) represents the delayed procurement quantity for raw material i, where (l-gj(t)) represents the quantity uncertainty level (a fraction of raw material being delayed). Eq. (6.21) represents the total procurement (replenishment) lead time for raw material i, fit), which includes the raw material order information lead time and booking transportation lead time in information flow and the raw material availability and raw material transportation lead time in material flow lf f)). Eq. (6.22) represents the total raw material i received by the manufacturer at period t taking into account the procurement lead time lj f) and the delayed RM procurement lead time Ifif). Eq. (6.23) updates the on-hand inventory state of raw material i. The raw material i inventory level... 

Since the balance sheet demonstrates a point in time, ending inventory is portrayed on the balance sheet for the current period, while the last period s inventory would be classified as beginning inventory. Stated another way, if one period ends with 1.5 million in inventory, the next period begins with 1.5 million in inventory. 

The annual United States import of vanilla beans jumped 34% in 1991, as importers and users replenished inventories (7). Indonesia was the largest suppher, accounting for 47% of the total the lower price for Indonesian beans is responsible for the increase in shipments. Users have been replacing Bourbon beans with Indonesian types, or blending in Indonesian beans, because they may still label their product as natural and meet other EDA specifications. 

Total hafnium available worldwide from nuclear zirconium production is estimated to be 130 metric tons annually. The annual usage, in all forms, is about 85 t. The balance is held in inventory in stable intermediate form such as oxide by the producers Teledyne Wah. Chang (Albany, Oregon) and Western Zirconium in the United States Ce2us in France Prinieprovsky Chemical Plant in Ukraine and Chepetsky Mechanical Plant in Russia (crystal bar). 

For chemical faciUties in the United States, hazard analysis is not an option if inventories of hazardous chemicals are maintained in amounts greater than the threshold quantities specified by the Occupational Safety and Health Administration (OSHA) regulation 1910.119. Many faciUties are finding that hazard analysis has many benefits. The process or procedure often works better, the quaUty of the product is improved, the process experiences less down time, and the employees feel more comfortable in the work environment after a hazard analysis has been completed. 

Chlor—alkah production is the largest iadustrial source of mercury release ia the United States (see Alkali and chlorine products). For the 1991 reporting year, chlor—alkah faciUties accounted for almost 20% of the faciUties that reported releases of mercury to the U.S. Environmental Protection Agency (EPA) for inclusion onto the Toxics Release Inventory (TRI) (25). 

Safety. A large inventory of radioactive fission products is present in any reactor fuel where the reactor has been operated for times on the order of months. In steady state, radioactive decay heat amounts to about 5% of fission heat, and continues after a reactor is shut down. If cooling is not provided, decay heat can melt fuel rods, causing release of the contents. Protection against a loss-of-coolant accident (LOCA), eg, a primary coolant pipe break, is required. Power reactors have an emergency core cooling system (ECCS) that comes into play upon initiation of a LOCA. 

HEU De-Enrichment. Highly enriched uranium (HEU), initially enriched to >93% U, for use in research, naval reactors, and nuclear weapons, may be de-enriched and fabricated into fuel for civihan nuclear reactors. An estimate of the world inventory of highly enriched uranium in the nuclear weapons states is provided in Table 6 (34). 

The amount of HEU that becomes avadable for civdian use through the 1990s and into the twenty-first century depends on the number of warheads removed from nuclear arsenals and the amount of HEU in the weapons complex that is already outside of the warheads, ie, materials stockpdes and spent naval reactor fuels. An illustrative example of the potential amounts of weapons-grade materials released from dismanded nuclear weapons is presented in Table 7 (36). Using the data in Table 7, a reduction in the number of warheads in nuclear arsenals of the United States and Russia to 5000 warheads for each country results in a surplus of 1140 t of HEU. This inventory of HEU is equivalent to 205,200 t of natural uranium metal, or approximately 3.5 times the 1993 annual demand for natural uranium equivalent. 

All the PMBs are Hsted on the U.S. EPA s Toxic Substances Control Act NonConfidential Chemical Substances Inventory (Table 8). In the early to mid-1980s, pseudocumene, mesitylene, hemimellitene, and trimethylbenzene were coveted by TSCA Section 8(a) Preliminary Assessment Information Rule (PAIR) reporting requirements (22) and by TSCA Section 8(d) for health and safety data (23). Mesitylene is the subject of a test rule subacute oral toxicity and subchtonic oral toxicity in tats were underway in 1994 (24). The Safe Drinking Water Act (SDWA) allows monitoring for pseudocumene and mesitylene at the discretion of the State (25). Of the PMBs, only pseudocumene is subject to SARA Tide III section 313 annual release reporting (26). 

Just-in-Time. Just-in-time closely followed the reintroduction of SPG into the American workplace. The efficacy of JIT was limited in the United States to an emphasis on keeping component inventories low to reduce the cost of inventory (16). More importantiy, however, JIT should be used to focus management attention on quahty problems. 

The wodd s largest sulfur iaveatories are stiH ia Canada. By the end of 1994, after significant vattiag, stocks iacreased by approximately 2.2 x 10 to 7.8 X 10 t. The United States, which had 4.2 million metric tons of sulfur inventories in 1982, reduced sulfur inventories to the lowest levels in a decade during 1992, a record year for phosphate fertilizer exports. This changed during 1993—1994, when phosphate fertilizer production eased and sulfur stocks increased to 1.1 million metric tons. Sulfur inventories in Poland and West Asia have also declined slightly (33). 

Poly(vinyl chloride) is Hsted on the TSCA inventory and the Canadian Domestic Substances List (DSL) as ethene, chloro-, homopolymer [9002-86-2]. Because polymers do not appear on the European Community Commercial Chemical Substances listing or EINECS, poly(vinyl chloride) is listed through its monomer, vinyl chloride [75-01-4]. In the United States, poly(vinyl chloride) is an EPA hazardous air pollutant under the Clean Air Act Section 112 (40 CER 61) and is covered under the New Jersey Community Right-to-Know Survey N.J. Environmental Hazardous Substances (EHS) List as "chloroethylene, polymer" with a reporting threshold of 225 kg (500 lb). 

Toxic Substances ControlA.ct Chemical Substances Inventory, U.S. Environmental Protection Agency, Office of Toxic Substances, United States Printing Office, Washington D.C., 1985. 

All four butanols are registered ia the United States on the Environmental Protection Agency Toxic Substances Control Act (TSCA) Inventory, a prerequisite for the manufacture or importation for commercial sale of any chemical substance or mixture ia quantities greater than a 1000 pounds (454 kg). Additionally, the manufacture and distribution of the butanols ia the United States are regulated under the Superfund Amendments and Reauthorization Act (SARA), Section 313, which requires that anyone handling at least 10,000 pounds (4545 kg) a year of a chemical substance report to both the EPA and the state any release of that substance to the environment. 

Multiftmctional SO removal catalyst systems have been ia commercial use siace 1985 ia the United States. Such systems have successfully reduced SO emissions in the FCCU regenerator by 50% when the regenerator is operating in the complete CO combustion mode (45). Modern-day additives can achieve a 50% SO reduction with only IS—2% of the additive in the circulating inventory, an amount small enough not to interfere with the cracking characteristics of the bulk FCC catalyst (45). 

Time-Dependent Cascade Behavior. The period of time during which a cascade must be operated from start-up until the desired product material can be withdrawn is called the equiUbrium time of the cascade. The equiUbrium time of cascades utilizing processes having small values of a — 1 is a very important quantity. Often a cascade may prove to be quite impractical because of an excessively long equiUbrium time. An estimate of the equihbrium time of a cascade can be obtained from the ratio of the enriched inventory of desired component at steady state, JT, to the average net upward transport of desired component over the entire transient period from start-up to steady state, T . In equation form this definition can be written as... 

The Toxic Substances Control Act (TSCA) was enacted in 1976 to identify and control toxic chemical ha2ards to human health and the environment. One of the main provisions of TSCA was to estabUsh and maintain an inventory of all chemicals in commerce in the United States for the purpose of regulating any of the chemicals that might pose an unreasonable risk to human health or the environment. An initial inventory of chemicals was estabhshed by requiring companies to report to the United States Environmental Protection Agency (USEPA) all substances that were imported, manufactured, processed, distributed, or disposed of in the United States. Over 50,000 chemical substances were reported. PoUowing this initial inventory, introduction of all new chemical substances requires a Premanufacturing Notification (PMN) process. To be included in the PMN are the identity of the new chemical, the estimated first year and maximum production volume, manufacture and process information, a description of proposed use, potential release to the environment, possible human exposure to the new substance, and any health or environmental test data available at the time of submission. In the 10 years that TSCA has been in effect, the USEPA has received over 10,000 PMNs and up to 10% of the submissions each year are for dyes (382)... 

The primary function of a continuous thickener is to concentrate sus-penaed solids by gravity settling so that a steady-state material balance is achieved, solids being withdrawn continuously in the underflow at the rate they are supphed in the feed. Normally, an inventory of pulp is maintained in order to achieve the desired concentration. This volume will vary somewhat as operating conditions change on occasion, this inventoiy can be used for storage of sohds when reed and underflow rates are reduced or temporarily suspended. 

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