冶金专业英语5.6.12

New developments in iron making 炼铁的新发展

During the past century, many efforts were made to develop processes for producing iron for steelmaking that could serve as alternatives to the conventional blast furnace.在过去的一个多世纪里，为了找到能够取代传统高炉的炼铁技术人类做了许多努力。This chapter presents a review of the alternativels processes that have achidved some measure of commercial success.本章将介绍成功商用于工业化炼铁体中的一些新工艺和新技术。

1.Direct reduction technology 1. 直接还原技术

In the history of iron and steelmaking technology, the first process is the direct reduction process. 在钢铁冶炼技术的历史上，最早使用的就是直接还原法。The blast furnace takes the place of the direct reduction process, which is the greteat imtronvement in the metallurgical technology. 高炉取代了直接还原法炼铁是冶金技术的重大进步。With the development of iron and steel industry, coke, on which blast furnace have depended for over 200 years, is becoming more expensive every expensive every year, and supplies of suitable coking coals are becoming scarcer. 随着钢铁工业的发展，200多年以来高炉一直使用的焦炭，价格每年都在增加，合适的焦煤越来越少。The direct reduction process was brought back at the end of the eighteenth century. 在18 世纪末，直接还原法又得以恢复。

Today, technology that produce iron by reduction of iron ore below the melting point of the iron producde is generally classified as direct reduction processes and the products referred to as direct reduced iron(DRI). 现在那些在低于铁的熔点温度以下用还原铁矿石的方法来冶金的技术通常称为直接还原法，其产品称为直接还原铁（DRI）。

According to the reducing agents used, direct reduction technology is commonly classed into two types: gas reduction processes and reduction processes with solid reducing agents. 根据还原剂的使用种类，直接还原法一般可分为气体还原法与固体还原法两类。According to the types of reduction reactors used, it is also classified into four main processes----fluidized bed, shaft furnace, retort, rotary kilin processes. 按使用的还原反应器类型，直接还原法主要分为流化床、竖炉、反应罐和回转窑法四大类。

(1)gas reduction processes （1）气体还原法

Reducing gases are carbon monoxide hydrogen or mixtures of two in gas reduction process. 在气体还原法中，还原剂是一氧化碳，氢气或这两种气体的混合物。They are normally obtained from natural gas. 它们通常从天然气中获得。The carbon monoxide and hydrogen are generated in the methane steam of natural gas reforming processes according to the reaction: CH4+H2O=CO+3H2天然气中甲烷转化为一氧化碳和氢气的反应如下: CH4+H2O=CO+3H2

The shaft-furnace process plays an important part in gas reduction processes. 竖炉法在气体还原法中起着重要的作用。More than 50% of all reduction processes are carried out in a shaft-furnace. For example, the Midrex process is a typical(Fig.5-1). 50％以上的还原过程是在竖炉中进行的，例如米德列法就是一个代表(图5-1)。

Midrex furnace has developed into a main production from of direct reduction processes, since the first steel plant was built and went into production in 1969. 米德列竖炉自1969年最早建成并投产以来，已发展成为直接还原去的主要形式。The largest Midrex furnace has an annual capacity of 800,000 ton. 最大的米德列紧炉年生产能力达到了80 万吨。

The main components of the process are the shaft furnace, the gas reformer, and