lesson 6.1 Synthetic
ammonia
content
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words
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Expressions and Technical Terms
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Words
合成氨
ammonia [ә`mәunjә] n. [化]氨, 氨水
synthetic [sin`Ѳetik] adj. 合成的, 人造的, 综合的
methanator [`meѲә`neitә] 甲烷转化器
description [diskripʃәn] n. 描写, 记述, 形容, 种类, 描述
anhydrous [æn`haidrәs] adj. 无水的
initiator [i`niʃieitә] 引发剂
其他
carbon [`ka:bәn] n. [化]碳(元素符号c)
hydrogen [`haidriʤәn] n. 氢
nitrogen [`naitrәʤәn] n. [化]氮
remainder [ri`meindә] n. 残余, 剩余物, 其他的人, [数]余数 adj. 剩余的
explosives [ik`splәusiv] n. 爆炸物 炸药
description [diskripʃәn] n. 描写, 记述, 形容, 种类, 描述
anhydrous [æn`haidrәs] adj. 无水的
brine [brain] n. 盐水
Expressions and Technical Terms
对应职业岗位
规格
1. monoammonium phosphates 磷酸氢一铵
2. diammonium phosphates 磷酸氢二铵
3. polymeric resins 聚合树脂
4. nitric acid 硝酸
5. catalytic reforming 催化重整
6. activated carbon 活性炭
7. carbon monoxide 一氧化碳
8. zinc oxide 氧化锌
9. knockout drum 分离鼓，分离罐
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Synthetic ammonia (NH3) refers to ammonia that
has been synthesized from natural gas.合成氨所涉
及的是已经从天然气中合成出来。
Natural gas molecules are reduced to carbon and
hydrogen. The hydrogen is then purified and reacted
with nitrogen to produce ammonia.天然气分子被减少
到碳和氢，那时纯氢气和氨气反应生成氨
Approximately 75 percent of the ammonia
produced is used as fertilizer, either directly as
ammonia or indirectly after synthesis as urea,
ammonium nitrate, and monoammonium or
diammonium phosphates.大约75%的氨被用作化肥或
直接或间接氨合成的尿素、硝酸铵。
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The remainder is used as raw material in the
manufacture of polymeric resins, explosives, nitric
acid, and other products.其余用作原料制造商分子树脂、
炸药、硝酸和其他产品。
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•Anhydrous ammonia is synthesized by reacting
hydrogen with nitrogen at a molar ratio of 3 to 1,
then compressing the gas and cooling it to -33°C.无
水氨合成反应的氢氮摩尔比3：1，然后压缩气体并冷却
到零下33摄氏度。
Nitrogen is obtained from the air, while hydrogen is
obtained from either the catalytic steam reforming of
natural gas (methane [CH4]) or naphtha, or the
electrolysis of brine at chlorine plants.氮是从空气中
获得的，而水是从催化重整天然气或石脑油或电解盐水在
氨气厂。
•
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Six process steps are required to produce
synthetic ammonia using the catalytic steam
reforming method: (1) natural gas desulfurization, (2)
catalytic steam reforming, (3) carbon monoxide (CO)
shift, (4) carbon dioxide (CO2) removal, (5)
methanation, and (6) ammonia synthesis. 第六个工艺
步骤必须出示合成氨采用催化水蒸气重整方法：（1）、
天然气的脱硫；（2）、催化重整；（3）、一氧化碳的
变换；（4）、二氧化碳的脱出；（5）、甲烷化；（6）、
氨水系统。
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The first, third, fourth, and fifth steps remove
impurities such as sulfur, CO, CO2 and water (H2O)
from the feedstock, hydrogen, and synthesis gas
streams. In the second step, hydrogen is
manufactured and nitrogen (air) is introduced into
this 2-stage process. The sixth step produces
anhydrous ammonia from the synthetic gas.第一、第
四和第五消除杂质，如硫、一氧化碳和原料中的水、氢和
合成气流体。在第二步中，氢气被加工和氮气一起被引进
工一段工艺。第六步是无水氨生产的合成气。
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9.2.1 Natural Gas Desulfurization天然气的脱硫
In this step, the sulfur content (as hydrogen
sulfide) in natural gas is reduced to below 280
micrograms per cubic meter (µg/m3) to prevent
poisoning of the nickel catalyst in the primary
reformer.在这步中硫含量的天然气减到低于280mg/m3，
以防止镍催化剂中毒，这个镍催化剂实在重整炉里的。
Desulfurization can be accomplished by using
either activated carbon or zinc oxide. Heavy
hydrocarbons can decrease the effectiveness of an
activated carbon bed.脱硫可通过使用活性炭或氧化锌。
氢氮化合物能降低活性炭床层的效力。
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This carbon bed also has another disadvantage
in that it cannot remove carbonyl sulfide.这种活性炭
床层也有另一种不利的地方就在于它不能吸除羧基碳。
Regeneration of carbon is accomplished by
passing superheated steam through the carbon bed.
A zinc oxide bed offers several advantages over the
activated carbon bed.碳的再生是由通过碳床层的过热
蒸汽完成的，氧化锌床层比活性炭存在许多优势。
Steam regeneration to use as energy is not
required when using a zinc oxide bed.蒸汽作为能源使
用而不被需要时，就是使用氧化锌床层。
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No air emissions are created by the zinc oxide
bed, and the higher molecular weight hydrocarbons
are not removed. Therefore, the heating value of the
natural gas is not reduced.由于氧化锌床层没有空气排
放会产生，而且更高分子量的烃类也不会被脱除。因此，
天然气的热值没有被减少。
9.2.2 Catalytic Steam Reforming蒸汽催化重整
Natural gas leaving the desulfurization tank is
mixed with process steam and preheated to 540°C.
天然气和水蒸气混合过程中离开脱硫罐且又被加热到540
摄氏度。
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Synthetic The mixture of steam and gas enters
the primary reformer (natural gas fired primary
reformer) and oil fired primary reformer tubes, which
are filled with a nickel-based reforming catalyst.
Approximately 70 percent of the CH4 is converted to
hydrogen and CO2. An additional amount of CH4 is
converted to CO.蒸汽与天然气的混合物进入重整炉。它
是被镍重整催化剂所充满的。额外的一部分天然气被分解
为CO。
This process gas is then sent to the secondary
reformer, where it is mixed with compressed air that
has been preheated to about 540°C.这步中的天然气
被送到第2重整炉，它是混合了被再次加热到540摄氏度
的压缩空气。
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Sufficient air is added to produce a final
synthesis gas having a hydrogen-to-nitrogen mole
ratio of 3 to 1. The gas leaving the secondary
reformer is then cooled to 360°C in a waste heat
boiler.足够的空气被添加到生产的最后工序，合成气的氢
氮比为3：1残留在二段重整炉内的天然气又被冷却到360
度在废热锅炉里。
9.2.3 Carbon Monoxide Shift一氧化碳的变换
After cooling, the secondary reformer effluent
gas enters a high temperature CO shift converter
that is filled with chromium oxide initiator and iron
oxide catalyst.
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The following reaction takes place in the carbon
monoxide converter:
CO + H2O → CO2+ H2
(1)
冷却后，二段重整炉的天然气进入高CO变换转换气，下
面这个反应式代替了CO的变换。
CO + H2O → CO2+ H2
(1)
The exit gas is then cooled in a heat exchanger.
In some plants, the gas is passed through a bed of
zinc oxide to remove any residual sulfur
contaminants that would poison the lowtemperature shift catalyst.出口气体在热交换气中被冷
却，在一些装置内气体通过氧化锌催化剂床层被脱除了一
些能使低温变换催化剂中毒的杂质.
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In other plants, excess low-temperature shift
catalyst is added to ensure that the unit will operate
as expected.在其他装置中，低温变换催化剂的添加能使
本单元按预期进行.
The low-temperature shift converter is filled with
a copper oxide/zinc oxide catalyst. Final shift gas
from this converter is cooled from 210 to 110°C and
enters the bottom of the carbon dioxide absorption
system.最后变换的气体从转换器中出来被冷却到110度
到210度，并且进入二氧化碳吸收系统的底部。
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Unreacted steam is condensed and separated
from the gas in a knockout drum. This condensed
steam contains ammonium carbonate ([(NH4)2
CO3 · H2O]) from the high-temperature shift
converter, methanol (CH3OH) from the lowtemperature shift converter, and small amounts of
sodium, iron, copper, zinc, aluminum and calcium.
未反应的蒸汽被冷凝并从分离罐中被分离出来。蒸汽冷凝
包括和少量的钠、铜、姓和铝。冷凝过程是被送到蒸发器
中来减少挥发性气体。如氨、甲醇和二氧化碳。
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9.2.4 Carbon Dioxide Removal
In this step, CO2 in the final shift gas is removed.
CO2 removal can be done by using 2 methods:
monoethanolamine (C2H4NH2OH，MEA) scrubbing
and hot potassium carbonate solution. The CO2 gas
is passed upward through an adsorption tower
countercurrent to a 15 to 30 percent solution of MEA
in water fortified with effective corrosion inhibitors.
在该步中，要脱除最后工段变换气中的CO2，二氧化碳的
脱除有两种方法，有有机氨和碳酸钾法。二氧化碳气体在
吸附塔中上升。逆流中MEA中溶质的含量从15%增大到
30%。
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After absorbing the CO2, the amine solution is
preheated and regenerated in a reactivating tower.吸
收完CO2后，氨组分被加热而且在再生塔中再生，反应塔
是通过加热来脱CO2的。
This reacting tower removes CO2 by steam
stripping and then by heating. The CO2 gas (98.5
percent CO2) is either vented to the atmosphere or
used for chemical feedstock in other parts of the
plant complex. CO2气体（98%的）不是被排放到大气
中就是利用其他装置化学原料的使用。再生的MEA被泵
打回吸收塔，在热交换器和冷凝器中被冷凝后。
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The regenerated MEA is pumped back to the
absorber tower after being cooled in a heat
exchanger and solution cooler.再生的MEA被泵打回吸
收塔，在热交换器和冷凝器中被冷凝后。
9.2.5 Methanation 甲烷化
Residual CO2 in the synthesis gas is removed by
catalytic methanation, which is conducted over a
nickel catalyst at temperatures of 400 to 600°C and
pressures up to 3,000 kilopascals (kPa) according to
the following reactions:合成气中剩余CO2的脱除是由
催化甲烷化完成的。这是发生在镍催化剂上的，温度在
400-600摄氏度之间，压力在300KP下通过以下反应进行：
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CO + 3H2 →CH4 + H2O
(2)
CO2 + H2 →CO + H2O
(3)
CO2 + 4H2 → CH4 + 2H2O
(4)
NaturalExit gas from the methanator, which has a
3:1 mole ratio of hydrogen and nitrogen, is then
cooled to 38°C.甲烷转化器出口气体中氢氮比为3：1，
且被冷切到了38度。
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9.2.6 Ammonia Synthesis
In the synthesis step, the synthesis gas from the
methanator is compressed at pressures ranging
from 13,800 to 34,500 kPa, mixed with recycled
synthesis gas, and cooled to 0°C.在氨的合成步骤中，
甲烷转化气的合成气丛13800KP压缩到34500KP。混合
回收的合成气，而且冷却到0度。
Condensed ammonia is separated from the
unconverted synthesis gas in a liquid-vapor
separator and sent to a let-down separator.浓缩氨是
从蒸汽分离器中未合成的气体中分离出来的，且被送到下
一级分离器中。
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The unconverted synthesis is compressed and
preheated to 180°C before entering the synthesis
converter, which contains iron oxide catalyst.为转化
的合成气被压缩且加热到180度在进合成塔之前，其中包
含铁氢化物催化剂。
Ammonia from the exit gas is condensed and
separated, then sent to the let-down separator.出口
气中的氨被压缩分离，而后送到下一级分离器。
A small portion of the overhead gas is purged to
prevent the buildup of inert gases such as argon in
the circulating gas system.一小部分的过热器被清除，
为了防止惰性气体，如循环系统的氩气。
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Ammonia in the let-down separator is flashed to
100 kPa at -33°C to remove impurities from the
liquid.分离器中的氨被闪蒸到100KP，在33度下。
The flash vapor is condensed in the let-down
chiller where anhydrous ammonia is drawn off and
stored at low temperature.这是为了除去液体形成的杂
质。闪蒸气体在下一级中被冷凝，其中无水氨被分离出来
并且在低温下储存起来。