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S E C T I O N IIISUPPLEMENTARY TEXTS FOR READING Text № 1 SHRIMP PACKER SWITHES TO CO2 FREEZING LOWERS COSTS 12% PER YEARVariety Seafoods Inc., is saving well over 16,000$ a year in refrigerant costs. The quick-frozen shrimp supplier switched both of its tunnel freezers from liquid nitrogen to liquid CO2. Estimates made at the time of conversion show CO2 cuts the cost of freezing a pound of shrimp to $0.052.In comparison, liquid nitrogen costs $0.059, a difference of $0.007 per pound. On the surface, it doesn‘t look that big. But Variety processes 2.5 million pounds of shrimp per year. Using CO2 cuts the refrigerant bill by $17.500. The company actually saves a little less, about $16.820. The difference is annual conversion costs, the price of equipment for CO2 amortized over eight years. Savings were verified by H. Roger Letchworth, executive vice-president. He reports freezing cost savings are at least as great as the above estimates. Just as important, CO2 preserves the quality of the shrimp as well as liquid nitrogen. The conversion was made to keep freezing costs in line. Ten years ago, liquid nitrogen was a sound business decision because it was lower priced than CO2. During the past several years, the situation has reversed, says the CO2 supplier. The reason for this reversal, says the supplier, is the higher cost to make liquid nitrogen. It takes five times more power to make a ton of LN2. So, the price is higher, says the supplier. However, the two cryogens cannot be compared on a one-to-one basis. Liquid CO2 has a lower heat coefficient. It doesn’t remove as much heat per pound as liquid nitrogen; thus, more is needed to freeze the shrimp. Variety’s justification sheet looks like this. In a year, the company uses 1,619 tons of CO2 – this is 304 tons more than liquid nitrogen. But, the company pays less for the carbon dioxide. It pays 129,496$ per year for CO2. Previously, it paid 147,280$ for liquid nitrogen. New equipment needed Some new equipment was necessary for the conversion. New storage tanks were installed, for instance. Liquid nitrogen is stored at low temperature (-32ºF) and low pressure ( about 15 psig). Liquid CO2 is held at higher temperature ( -2ºF) and much higher pressure (200-300 psig). Other modifications include less complicated insulation. Liquid CO2 isn’t as cold as nitrogen, and less sensitive to ambient temperature. In addition, a control system was installed to prevent CO2 from flashing into snow and vapor, and cloging the pipes. In this system, temperature fluctuations are sensed and compared to a setpoint. Differences result in a signal to a control valve, which compensates by increasing or reducing CO2 flow. Pressure is also regulated. Should pressure drop below 150 psig – the point where snow forms – the pressure regulator in the vapor line opens. Vapor brings pressure back to normal. How shrimp is processed. The shrimp process begins with freshly caught shrimp from both the Atlantic and Gulf of Mexico. Shrimp are unloaded, size-graded, then cooked or breaded, depending on what product is required. After further inspections, shrimp enter one of two 5,000 pound/shift tunnels. Shrimp travel through these freezers on conveyors, then are discharged directly into shipping containers or cartons. Product is distributed through a network of 50 brokers, from Canada to Puerto Rico. Throughout processing, quality is continuously monitored. Ready-to-ship shrimp are regularly sampled by quality control. And from time to time, samples of breaded shrimp- Variety’s biggest seller- are deepfried. The seasoned breading must form a golden-brown, crisp coating after frying for 3-4 minutes at 350F. This is important because a coating that isn’t crisp indicates too much moisture. Примечания к тексту:
1. Ответьте на вопросы по тексту. 1.Variety Seafoods Inc. cuts the cost of freezing shrimp over $16,000 a year, doesn’t it? 2.What made these savings possible? 3.What type of freezers does the company use? 4.What new equipment was necessary for the conversion? 5.What other modifications were made? 2.Опишите процесс переработки креветок. 3.Переведите следующие предложения на английский язык письменно. 1.Исполнительный вице-президент компании подтвердил экономию расходов на замораживание креветок. 2.Десять лет назад компания использовала жидкий азот, и это было правильное (благоразумное) решение, так как его стоимость была ниже, чем СО2. 3.Креветки, обжаренные в сухарях, - это основная (главная) продукция, производимая компанией Variety. 4.Переведите резюме этого текста на русский язык. Freshly caught shrimp are inspected before entering the converted freeze tunnel. Going from LN2 to CO2 lowered refrigerant costs by more than $16,000 a year. 5.Напишите краткое изложение текста на русском языке. Прокомментируйте часть текста, которая показалась вам наиболее интересной. Text № 2. | ||||||||||||||||
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