问题 问答题 简答题

氧化铝生产,水的平衡较复杂,它贯穿于整个流程之中,试述系统中水的脱除途径是什么?

答案

参考答案:

一是产品焙烧脱除氢氧化铝附着水和结晶水。

二是外排赤泥带走的附着水和结晶水。

三是排入下水道和循环水中部分。

四利用蒸发器浓缩各种母液脱除多余的水。

五自蒸发

填空题
阅读理解

Chicken feathers are useful, and not just to a chicken. Some go into pillows, coats and other products. But countless chicken feathers go to waste.

In the United States, billions of chickens are produced yearly. Most of their feathers are thrown away.

But instead of being buried in land, some feathers could find a future in plastics(塑料).

One of the products they have developed is a flowerpot(花盆). It may look like other flowerpots. But the container breaks down in the earth within one to five years. And as it breaks down, it naturally becomes nutrient(营养物) in the soil.

The environmentally friendly flowerpot is the work of two researchers. Walter Schmidt is with the Agricultural Research Service, part of the United States Agriculture Department. Masud Huda is with the Horticultural Research Institute, a private(私人) organization(组织).

Walter Schmidt has been working to find uses for chicken feathers since the 1990s. Progress in 2002 showed that plastic made from feathers could be formed like other plastics.

He says feathers are much stronger and last(持续) longer than another plant material. "Feathers are stronger. By design, feathers are also more durable(耐用的). And the other part about it is if feathers were twice as heavy, or half as strong, then birds couldn't fly."

He points out that traditional flowerpots made from other plastics can last much longer. But he wonders if there is really a need. He says most flowerpots are never re-used.

"Why would you want a plastic that you use for a year to last for two hundred years? It makes no sense. You want to match the product with the use." said Walter Schmidt.

Walter Schmidt and Masud Huda are now adding another chicken product to their flowerpots -- chicken waste. The waste will add more nutrients to the soil as the pot breaks down. The scientists say they hope their flowerpot will be on the market in a year or two.

小题1:What do people mainly deal with feathers?

A.Feathers are used to make pillows, coats and other products.

B.Most feathers are paid no attention to.

C.Most feathers are used as nutrient

D.Most feathers are used to make flowerpots小题2:What’s the advantage of the flowerpots?

A.They won’t last long.

B.They can’t break

C.They are environmentally friendly

D.They can be reused小题3:What does Walter Schmidt think of traditional flowerpots?

A.Too heavy

B.Too old

C.Never re-used

D.lasting longer but unnecessary小题4:What do you think is the main idea of the passage?

A.Chicken and its feathers

B.How to deal with feathers

C.feathers made into flowerpot

D.New flowerpots