油气储运专业英语（英汉互译）

dehydration eliminates these possible difficulties and is normally required by gas sales agreements. When gas is dehydrated its dewpoint (the temperature at which water will condense from the gas) is lowered.

由气井生产的天然气常被水蒸气所饱和。从多数气体处理工艺单元流出的气体也为水蒸气所饱和。水蒸气本身无害，但压缩或冷却气体时产生的液态积存在管道或固态水常给气体处理带来麻烦。液态水会加速管道和其他设备的腐蚀;存在液态水时可能生成水合物，会堵塞阀、管件甚至管道;液态水积存在管道低洼处会降低管道的输送能力。气体销售合同中常要求脱去水蒸气，以消除上述可能发生的故障。气体脱水后，其露点(气体内水凝析时的温度)降低。

A typical dehydration specification in the U. S. Gulf Coast is 7 lb of water vapor per MMscf of gas (7 lb/MMscf). This gives a dew point of around 32 0F for 1 000 psi gas. In the northern areas of the U.S. and Canada the gas contracts require lower dew points or lower water vapor concentrations in the gas. Water vapor concentrations of 2 -- 4 lb/MMscf are common. If the gas is to be processed at very low temperatures, as in a cryogenic gas plant ,water vapor removal down to 1 ppm may be required.

在美国海湾地区，典型的脱水技术规定为7 1b/MMscf，相当于1000 psi压力下气体的露点约为320F。在美国北部地区和加拿大，气体合同中会要求更低的露点，或要求气体内水蒸气浓度更低。水蒸气浓度常为2--4 Ib/MMacf。若需要在很低的温度下加工气体，如需在气体深冷处理厂加工气体，则可能需要将水蒸气脱至1/106以下。

1 .5 The Trays and Packing

1.5 塔板和填料

The number of actual equilibrium stages determines the number of flashes that will occur. The more stages, the more complete the split , but the taller and more costly the tower. Most condensate stabilizers will normally contain approximately five theoretical stages. In a refluxed tower, the section above the feed is known as the rectification section，while the section below the feed is known as the stripping section. The rectification section normally contains about two equilibrium stages above the feed and the stripping section normally contains three equilibrium stages.

真实平衡级数确定了发生闪蒸的次数。级数愈多，物料的分离愈完善，但会使塔高增加，塔的投资增大。多数凝析液稳定塔一般有5个理论级数。在带有回流的塔内，进料以上部分称精馏段，进料以下部分称提馏段。进料板以上的精馏段一般含2个平衡级，而提馏段一般含3个平衡级。

Theoretical stages within a tower are provided by actual stage devices (typically either trays or packings). The actual diameter and height of the tower can be derived using manufacturer’s data for the particular device. The height of the tower is a function of the number of theoretical stages and of the efficiency of the actual stages. The diameter of the tower is a function of the hydraulic capacity of the actual stages.

塔内的理论级由真实级设备提供(一般为塔板或填料)。参照制造商为特定装置提供的数据，可得到塔的真实直径和塔高。塔高是理论级数和真实级效率的函数。塔的直径是真实级水力性能的函数。

1 .5 .1 Trays

1.5.1塔板

For most trays, liquid flows across an “ active area” of the tray and then into a “downcomer” to the next tray below, etc. Inlet and/or outlet weirs control the liquid distribution across the tray. Vapor flows up the tower and passes through the tray active area, bubbling up through (and thus contacting) the liquid flowing across the tray. The vapor distribution is controlled by (1) perforations in the tray deck (sieve trays), (2) bubble caps (bubble cap trays), or (3) valves (valve trays).

对多数塔板来说，液体流过塔板的“活性面积”后，由降液管流至下一层塔板，并依此类推.人日和/或出口堰板控制着横向流经塔板的液体分布。蒸气沿塔向上流动并通过塔板的活性面积，它以鼓泡方式通过流经塔板的液层(这样可使气液密切接触)。蒸气的分布由以下方法控制:在塔板上开孔(筛板);泡罩(泡罩塔板);阀(阀板)。

Trays operate within a hydraulic envelope. At excessively high vapor rates, liquid is carried upward from one tray to the next (essentially back-mixing the liquid phase in the tower). For valve trays and sieve trays, a capacity limit can be reached at low vapor rates when liquid falls through the tray floor rather than being forced across the active area into the downcomers. Because the liquid does not flow across the trays, it misses contact with the vapor, and the separation efficiency drops dramatically.

塔板在水力包络线内工作。蒸气流量过大会将液体从下层塔板带至上层塔板(液相在塔内返混)。对阀板和筛板，在蒸气流量过低时会达到板的工作下限，此时液体不再横向流经活性面积进人降液管，而是通过板底向下滴漏。由于液体没有横向流过塔板，液体与蒸气没有接触，所以使分离效率大大下降。

Trays are generally divided into four categories：sieve trays, valve trays, bubble cap trays, and high capacity/high efficiency trays.

塔板一般分为四类：筛塔板、阀板、泡罩塔板、高处理量/高效率塔板。

1. 5. 1.1 Sieve Trays 1. 5. 1.1筛塔板

Sieve trays are the least expensive tray option. In sieve trays, vapor flowing up through the tower contacts the liquid by passing through small perforations in the tray floor ( Fig. l-7b). Sieve trays rely on vapor velocity to exclude liquid from

falling through the perforations in the tray floor. If the vapor velocity is much lower than design liquid will begin to flow through the perforations rather than into the downcomer. This condition is known as weeping. Where weeping is severe, the equilibrium efficiency will be very low. For this reason，sieve trays have a very small turndown ratio.

筛板是塔板中最便宜的。采用筛板时，向上流经塔的蒸气通过筛板上的小孔与液体接触（图1-7b）筛板依靠蒸气速度阻止塔板上的液体向下滴漏。若蒸气流速低于设计流速太多，液体将不再进人降液管，而是通过小孔向下滴漏。这种工况称为漏液。漏液严重时会使平衡效率很低，因此筛板的流量调节比很小。

1. 5.1. 2 Valve Trays 1.5.1.2 阀板 Valve trays are essentially modified sieve trays. Like sieve trays, holes are punched in the tray floor. However，these holes are much larger than those in sieve trays. Each of these holes is fitted with a device called a “ valve”. Vapor flowing up through the tower contacts the liquid by passing through valves in the tray floor (Fig. l-7c). Valves can be fixed or moving. Fixed valves are permanently open and operate as deflector plates for the vapor coming up through the holes in the tray floor. For moving valves， vapor passing through the tray floor lifts the valves and contacts the liquid. Moving valves come in a variety of designs, depending on the manufacturer and the application. At low vapor rates，valves will close, helping to keep liquid from falling through the holes in the deck. At sufficiently low vapor rates, a valve tray will begin to weep. That is, some liquid will leak through the valves rather than flowing to the tray downcomers. At very low vapor rates，it is possible that all the liquid will fall through the valves and no liquid will reach the downcomers. This severe weeping is known as “dumping”. At this point，the efficiency of the tray is nearly zero.

阀板基本上是改良的筛板。如筛板类似，阀板上开有孔。然而，这些孔比筛板的孔大的多。每个孔都装有称为“阀”的设备。塔内向上流动的蒸汽通过塔盘板上的阀与液体接触（图1-7c）。阀门可以固定的或浮动的。固定式阀是常开的，工作时它犹如通过塔板孔向上流动的蒸气折流板。对于浮动阀，通过塔板的蒸气举升阀瓣并与液体接触。根据制造商的不同和塔的使用条件，浮动阀有各种设计。当蒸气流量较低时，阀处于关闭状态，防止液体通过塔板上的孔向下滴漏。当蒸气流量很低时，阀板将开始滴漏，即一些液体通过阀孔泄漏而不流向塔板的降液管。当蒸气流量极低时，液体可能全部通过阀门漏失，而不进人降液管。这种严重的液体泄漏称为“卸液”，此时塔板的效率几乎为零。

1. 5.1. 3 Bubble Cap Trays 1. 5.1. 3汽泡罩板

In bubble cap trays, vapor flowing up through the tower contacts the liquid by passing through bubble caps (Fig. l-7a). Each bubble cap assembly consists of a riser and a cap. The vapor rising through the column passes up through the riser in the tray floor and then is turned downward to bubble into the liquid surrounding the cap. Because of their design，bubble cap trays cannot weep. However bubble cap trays are also more expensive and have a lower capacity/higher pressure drop than valve trays or sieve trays.

在泡罩塔中，沿着塔向上流动的蒸汽流经泡罩与液体接触（图l-7a）。泡罩由一个立管（升气管）和一个帽组成。沿着塔向上流动的蒸汽流经安装在塔板上的立管，然后将将改变气流的方向，向下在泡罩四周的液层内鼓泡。这样的设计可以使汽泡罩塔不会发生滴漏。然而泡罩塔十分昂贵，与阀板或筛塔板相比其处理量低/压力降高。

1. 5.1. 4 High Capacity/High Efficiency Trays 1. 5.1. 4高容量/高效率塔板

High capacity/high efficiency trays have valves or sieve holes or both. They typically achieve higher efficiencies and capacities by taking advantage of the active area under the downcomer. At this time, each of the major vendors has its own version of these trays, and the designs are proprietary.

高容量/高效率塔板有阀孔或筛孔或两者都有。这些塔板充分利用了降液管下方的活性面积，可以获得高的效率和处理量。目前，各主要的供应商都有其自己的此类塔板，这些塔板的设计具有专利。

1 5.2 Packing 5.2 1填料

Packing typically comes in two types：random and structured. 填料通常分为两类：随机填料和规整填料。

Liquid distribution in a packed bed is a function of the internal vapor/liquid traffic,type of packing employed, and the quality of the liquid distributors mounted above the packed bed. Vapor distribution controlled by the internal vapor/liquid traffic, by the of packing employed, and by the quality of the vapor distributors located below the packed beds.

在填料床内，液体的分布取决于气液在填料内的流动情况、所用填料类型以及在填料床上方安装的液体分配器的质量。塔内蒸气的分布取决于气液在填料内的流动情况、所用填料类型以及安装在填料床下方蒸气分配器的质量。

Packing material can be plastic,metal,or ceramic.Packing efficiencies can be expressed as HETP (height equivalent to a theoretical plate.

填料的材料有塑料、金属或陶瓷。填料的效率表示为HETP，即理论塔板等效高度。

1.5.2.1 Random Packing

1.5.2.1随机填料

A bed of random packing typically consists of a bed support (typical a gas injection support plate) upon which pieces of packing material are randomly arranged ( they are poured or dumped onto this support plate). Bed limiters, or hold-downs, are sometimes set above random beds to prevent the pieces of packing from migrating or entraining upward. Random packing comes in a variety of shapes and sizes. For given shape (design) of packing, small sizes have higher efficiencies and lower capacities than large sizes.

随机填料床包括床支撑(一般为能注人气体的支撑板)和在支撑上随机堆放的填料（常将填料倒在该支撑板上）。随机填料床上方有时安装有压紧装置，防止填料移动或被向上气流携带。随机填料有各种形状和大小。对于给定形状(设计)的填料，小填料的效率比大填料高，但处理量低。

Fig. 1-8 shows a variety of random packing designs. An early design is known as a Raschigring. Raschig rings are short sections of tubing and are low-capacity, low-efficiency,high-pressure drop devices. Today’s industry standard is the slotted metal (Pall) ring. A packed bed made of 1 in slotted metal rings will have a higher mass transfer efficiency and a higher capacity than will a bed of 1 in Raschig rings. The HETP for a 2 in slotted metal ring in a condensate stabilizer is about 36 in. This is slightly more than a typical tray design, which would require 34 in (1.4 trays X 24 in tray spacing) for one theoretical plate or stage.

图1-8所示为各种随机填料。早期设计中为拉西环。拉西环是一段短管，它是处理量低、效率低、压降高的填料。现在的工业标准是使用开槽的金属(鲍尔)环。与拉西环相比，1 in开槽金属环构成的填料床有较高的传质效率和较大的处理量。在凝析液稳定塔内，2 in开槽金属环的理论板等效高度约为36 in，略大于塔板典型设计中每块理论板(或理论级)所需的板间距34in（1.4块塔板×24in塔板间距）。

1. 5. 2. 2 Structured Packing 1. 5. 2. 2规整填料

A bed of structured packing consists of a bed support upon which elements of structured packing are placed. Beds of structured packing typically have lower pressure drops than beds of random packing of comparable mass transfer efficiency. Structured packing elements are composed of grids (metal or plastic) or woven mesh (metal or plastic) or of thin vertical crimped sheets (metal, plastic, or ceramic) stacked parallel to each other. Fig. 1-9 shows examples of the vertical crimped sheet style of structured packing.

规整填料床包括床支撑和在支撑上放置的规整填料组件。在传质效率相当的条件下，规整填料床的压降一般比随机填料床小。规整填料组件由格栅(金属或塑料)或编织丝网(金属或塑料)或相互平行堆积的垂直波纹薄板(金