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汽冷旋风分离器的结构是怎样的?

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参考答案:

汽冷式旋风分离器上半部分为圆柱形,下半部分为锥形。分离器烟气出口(旋风分离器的中心筒)为圆筒形钢板件形成的一个端部敞开的圆柱体,长度几乎伸至旋风分离器圆柱体一半位置。进入分离器的细颗粒和烟气旋转向下流动至圆体区域而后向上流动,被分离的颗粒落入圆柱体的底部,进入与分离器相连接的立管和回料器,没有被分离的细小颗粒和烟气由分离器烟气出口离开分离器。

旋风分离器为膜式包墙过热器结构。其顶部与底部均与环形联箱相连接,墙壁管子在顶部向内弯曲,使得在旋风分离器管子和烟气出口筒之间形成密封结构。其内部流动的介质为经过旋风分离器进口烟道受热面加热过的过热蒸汽,过热蒸汽先由分离器进口烟道受热面的出口联箱经导汽管引至旋风分离器下部环形联箱,后经包覆在分离器四周的管子,受热后引至上部环形联箱,后经导汽管进入侧包墙过热器。

旋风分离器的内表面焊接了大量短销钉,并敷设有防磨材料,其厚度距管子外表面有20~30㎜。汽冷分离器外部为类似于水冷壁外部的保温层和护板。

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(D)

Consumers are being confused and misled by the hodge-podge of environmental claims made by household products, according to a "green labeling" study published by Consumers International Friday.

Among the report’s more outrageous findings-a German fertilizer described itself as "earthworm friendly" a brand of flour said it was "non-polluting" and a British toilet paper claimed to be "environmentally friendlier".

The study was written and researched by Britain’s National Consumer Council (NCC) for lobby group Consumer International. It was funded by the German and Dutch governments and the European Commission.

"While many good and useful claims are being made, it is clear there is a long way to go in ensuring shoppers are adequately informed about the environmental impact of products they buy." said Consumers International director Anna Fielder.

The 10-country study surveyed product packaging in Britain, Western Europe, Scandinavia and the United States. It found that products sold in Germany and the United Kingdom made the most environmental claims on average.

The report focused on claims made by specific products, such as detergent insect sprays and by some garden products. It did not test the claims, but compared them to labeling guidelines set by the International Standards Organization (ISO) in September, 1999.

Researchers documented claims of environmental friendliness made by about 2,000 products and found many too vague or too misleading to meet ISO standards.

"Many products had specially-designed labels to make them seem environmentally friendly, but in fact many of these symbols mean nothing." said report researcher Philip Page.

"Laundry detergents made the most number of claims with 158. Household cleaners were second with 145 separate claims, while paints were third on our list with 73. The high numbers show how very confusing it must be for consumers to sort the true from the misleading." he said.

The ISO labeling standards ban vague or misleading claims on product packaging, because terms such as "environmentally friendly" and "non-polluting" can not be verified. "What we are now pushing for is to have multinational corporations meet the standards set by the ISO." said Page.

It can be inferred from the passage that the lobby group Consumer International wants to().

A. make product labeling satisfy ISO requirements

B. see all household products meet environmental standards

C. warn consumers of the danger of so-called green products

D. verify the efforts of non-polluting products