The content of naphthalene in raw gas is usually 10-15g / m3, and most of naphthalene is dissolved in the tar condensed in the gas collector and primary cooler. The naphthalene in the gas has a great influence on the ammonia washing operation. When the content of naphthalene in the gas is high, the naphthalene will deposit together with the scale in the ammonia washing process, which will cause the blockage of the ammonia washing equipment, thus destroying the normal operation of ammonia washing and reducing the ammonia recovery rate. More seriously, the corrosive gases such as ammonia, hydrogen sulfide and hydrogen cyanide enter the crude benzene section along with the gas Serious corrosion and clogging of the equipment for debinding. Therefore, naphthalene in gas must be cleaned according to the requirements of ammonia washing.

　　目前，各焦化企業(yè)采用的油洗萘工藝一般分為兩種，一種是煤氣終于冷卻與洗萘同時進(jìn)行的終冷油洗萘，稱為冷油法洗萘。另一種是終冷前油洗萘，稱為熱油法洗萘。洗萘采用的吸收劑通常為本廠產(chǎn)的焦油洗油。下面簡單的介紹一下冷油法洗萘工藝。

　　At present, the process of naphthalene washing with oil adopted by coking enterprises is generally divided into two types. One is the final cooling of naphthalene washing by oil at the same time of gas cooling and naphthalene washing, which is called cold oil naphthalene washing. The other is washing naphthalene with oil before final cooling, which is called hot oil washing naphthalene. The absorbent used for naphthalene washing is usually tar wash oil produced by our factory. The following is a brief introduction to the cold oil washing naphthalene process.
                

　　鼓風(fēng)機(jī)后的煤氣經(jīng)電捕焦油器進(jìn)入橫式冷卻管束及浮閥塔盤組成的終冷洗萘塔，在此煤氣由45℃左右被冷卻至25℃左右，同時煤氣中大部分萘被清除。

　　The gas after the blower enters into the final cold washing naphthalene tower composed of horizontal cooling tube bundle and float valve tray through electric tar precipitator, where the gas is cooled from about 45 ℃ to about 25 ℃, and most naphthalene in the gas is removed.

　　由于冷卻溫度低于初冷后煤氣露點(diǎn)，故在洗萘的同時，有水汽冷凝進(jìn)入洗萘油中。

　　Since the cooling temperature is lower than the dew point of the gas after primary cooling, water vapor condenses into the naphthalene washing oil while washing naphthalene.

　　來自粗苯工段溫度為28℃-30℃的脫苯貧油，由塔頂一塊塔盤進(jìn)入洗萘段，通過浮閥塔盤與煤氣逆流密切接觸以吸收煤氣中的萘，然后進(jìn)入裝有橫管式冷卻管束的冷卻段。在被煤氣冷卻的同時，油與煤氣再次在管束外壁接觸，并沖洗凝結(jié)在管壁上的萘。氨油流至塔底，成為含萘含水分富油。然后自流經(jīng)加熱器至85-90℃，進(jìn)行加熱破乳，再送至三個串聯(lián)的脫水槽進(jìn)行脫水。脫出的分離水直接或經(jīng)分離水槽兌入富氨水槽中。脫水后的含萘富油兌入洗苯富油中。脫水槽排出的乳化物經(jīng)乳化物槽送往粗苯工段的地下放空槽。為提高油水分離效果，還在一、二脫水槽中加入適量的清水。

　　The lean oil from crude benzol section with temperature of 28 ℃ - 30 ℃ enters naphthalene washing section from a tray at the top of the tower. It is in close contact with the gas countercurrent through the float valve tray to absorb naphthalene in the gas, and then enters the cooling section with horizontal tube cooling tube bundle. While being cooled by gas, the oil and gas contact with each other again on the outer wall of the tube bundle, and the naphthalene condensed on the pipe wall is washed. The ammonia oil flows to the bottom of the tower and becomes rich oil with naphthalene and water. Then, it is heated to 85-90 ℃ by self flowing heater, and then sent to three dehydration tanks in series for dehydration. The separated water is directly or through the separation tank into the ammonia rich water tank. The dehydrated naphthalene rich oil is mixed into the benzene washing rich oil. The emulsion discharged from the dewatering tank is sent to the underground vent tank of crude benzene section through the emulsion tank. In order to improve the effect of oil-water separation, appropriate amount of water is added into the first and second dewatering tanks.

　　冷油法洗萘工藝特點(diǎn)：連續(xù)洗萘；洗萘富油連續(xù)脫水和再生；煤氣的終冷卻和洗萘在同一設(shè)備中進(jìn)行；洗萘操作處于較低的溫度。因而洗萘效果較好。

　　The features of cold oil naphthalene washing process are as follows: continuous naphthalene washing; continuous dehydration and regeneration of rich naphthalene washing oil; final cooling of gas and naphthalene washing are carried out in the same equipment; naphthalene washing operation is at a low temperature. Therefore, the effect of washing naphthalene is better.

　　影響洗萘效果的因素。

　　Factors affecting the effect of naphthalene washing.

　　一， 洗萘的操作溫度。當(dāng)循環(huán)油含萘一定時，溫度越低，則與其平衡的煤氣含萘量越少；當(dāng)煤氣中含萘量一定時，溫度越低，則允許的循環(huán)油含萘濃度越高。因此，降低洗萘的操作溫度，有利于提高油洗萘效率。洗萘操作溫度也不應(yīng)過低，入塔循環(huán)洗油溫度比煤氣露點(diǎn)溫度高10℃左右。

　　1、 The operating temperature of naphthalene washing. When the naphthalene content in the circulating oil is constant, the lower the temperature is, the less the naphthalene content in the balance gas is; when the naphthalene content in the gas is constant, the lower the temperature, the higher the allowable naphthalene concentration of the circulating oil is. Therefore, reducing the operating temperature of naphthalene washing can improve the efficiency of naphthalene washing. The operating temperature of naphthalene washing should not be too low. The temperature of circulating washing oil entering the tower is about 10 ℃ higher than that of gas dew point.

　　二， 煤氣溫度。為減輕洗萘塔的負(fù)荷，盡可能降低入塔煤氣的含萘量，則需要控制好入塔煤氣溫度。首先，應(yīng)控制好初冷器的操作，使初冷器后煤氣集合溫度低于25℃。

　　2、 Gas temperature. In order to reduce the load of naphthalene washing tower and reduce the naphthalene content of the gas entering the tower as much as possible, it is necessary to control the temperature of the gas entering the tower. First of all, the operation of the primary cooler should be controlled to make the gas collection temperature after the primary cooler lower than 25 ℃.

　　三， 洗萘油質(zhì)量。洗萘油質(zhì)量是影響洗萘效果的重要因素。對不同工藝的洗萘油質(zhì)量有不同的要求。以冷油法洗萘為例。根據(jù)多個焦化企業(yè)的經(jīng)驗，我國焦化企業(yè)已經(jīng)形成了一套質(zhì)量標(biāo)準(zhǔn)。具體如下：

　　3、 Quality of naphthalene washing oil. The quality of naphthalene washing oil is an important factor affecting the effect of naphthalene washing. There are different requirements for the quality of naphthalene washing oil with different processes. Take naphthalene washing with cold oil as an example. According to the experience of many coking enterprises, a set of quality standards has been formed in China's coking enterprises. The details are as follows:

　　油洗萘質(zhì)量標(biāo)準(zhǔn)

　　Quality standard of naphthalene in oil washing20℃時密度：≤1.07kg/g，黏度E25≤1.7，270℃前餾出量：≥50%，300℃前餾出量≥85%。

　　At 20 ℃, the density: ≤ 1.07kg/g, the viscosity e25 ≤ 1.7270 ℃, the distillation amount before 70 ℃ and the distillation amount before 300 ℃ are more than or equal to 85%.

　　以上內(nèi)容是關(guān)于煤氣中萘的清除方法，希望對大家有所幫助，如您想要選購精萘，了解具體精萘價格歡迎咨詢我們的網(wǎng)站。

　　The above content is about the removal method of naphthalene in gas, hope to help you, if you want to buy refined naphthalene, understand the specific refined naphthalene price, welcome to consult our website.