1、 Composition of kitchen smoke exhaust system

廚房排煙系統(tǒng)主要由集煙罩、排煙管、消防閥、油煙凈化器設(shè)備、排煙風(fēng)機(jī)（含消聲器）、廚房綜合送風(fēng)裝置等組成。油煙凈化器設(shè)備的類型和運(yùn)行方式可根據(jù)實(shí)際情況選擇。安裝油煙凈化器前，應(yīng)計(jì)算排煙系統(tǒng)各部分的實(shí)際運(yùn)行參數(shù)，包括運(yùn)行阻力和排氣量。如果要新建項(xiàng)目，應(yīng)充分考慮在排氣系統(tǒng)上安裝油煙凈化器的影響。如果是改造項(xiàng)目，安裝油煙凈化器時(shí)需要重新計(jì)算排氣系統(tǒng)。必要時(shí)對廚房集煙罩、排煙管、整體送風(fēng)裝置進(jìn)行改造，更換排風(fēng)機(jī)。

The kitchen smoke exhaust system is mainly composed of smoke collecting hood, smoke exhaust pipe, fire valve, lampblack purifier equipment, smoke exhaust fan (including muffler), kitchen integrated air supply device, etc. The type and operation mode of lampblack purifier can be selected according to the actual situation. Before installing the lampblack purifier, the actual operating parameters of each part of the smoke exhaust system shall be calculated first, including operating resistance and exhaust volume. If a new project is to be built, the impact of installing a fume purifier on the exhaust system shall be fully considered. If it is a reconstruction project, the exhaust system needs to be recalculated when installing the lampblack purifier. If necessary, the kitchen hood, smoke exhaust pipe and integral air supply device shall be modified, and the exhaust fan shall be replaced.

二、集煙罩

2、 Smoke collecting hood

集煙罩一般為整體加工，包括過濾、集油、集水等設(shè)備，主要由廚房公司制造。其外觀應(yīng)均勻、美觀、易于清潔。廚房通風(fēng)時(shí)，需要添加一定量的新鮮空氣。一方面可以平衡空氣壓力，避免廚房負(fù)壓過大（一般小于5pa），另一方面可以降低廚房溫度，改善工作環(huán)境。烹飪煙氣收集罩主要有三種類型：

The smoke collection hood is generally processed as a whole, including filtering, oil collection, water collection and other equipment, and is mainly manufactured by professional kitchen companies. The appearance shall be uniform, beautiful and easy to clean. When the kitchen is ventilated, a certain amount of fresh air needs to be added. On the one hand, it can balance the air pressure to avoid excessive negative pressure in the kitchen (generally less than 5pa), on the other hand, it can reduce the kitchen temperature and improve the working environment. There are three main types of cooking fume collection hoods:

（1） 簡易集氣罩為無油供氣設(shè)備，適用于各種靈活場所，加工安裝方便，低廉。但由于缺乏送風(fēng)設(shè)備，集風(fēng)效果差，容易使煙氣在廚房工作人員面前旋轉(zhuǎn)，容易造成油滴分散。

(1) The simple gas collecting hood is an oil-free gas supply equipment, which is suitable for various flexible places. It is easy to process and install, and the price is low. However, due to the lack of air supply equipment, the air collection effect is poor, which is easy to make the smoke rotate in front of the kitchen staff and cause oil droplets to disperse.

（2） 帶油罩和供氣裝置的空氣濃縮器能更好地收集烹飪過程中產(chǎn)生的煙霧，油滴不會脫落。只要送風(fēng)合理，廚房操作人員工作面空氣質(zhì)量良好。但安裝要求高，投資大。

(2) The air concentrator with oil hood and air supply device can better collect the smoke generated during cooking, and the oil drops will not fall off. As long as the air supply is reasonable, the air quality of the kitchen operator's working face is good. However, the installation requirements are high and the investment is large.

（3） 水和氣體收集（煙霧）蓋

(3) Water and gas collection (smoke) cover

輸水集氣罩的設(shè)計(jì)原則是與油煙碰撞后形成水幕循環(huán)，凈化油煙。影響輸水集氣罩使用效果的關(guān)鍵是形成連續(xù)的水幕，循環(huán)水系統(tǒng)需要定期清洗。事實(shí)上，由于管理不善，大多數(shù)水和氣體（煙霧）帽不會形成連續(xù)的水幕，而只能形成間歇性水滴或小水柱，這使得它們無法使用。

The design principle of the water conveyance and gas collecting hood is to form a water curtain circulation after collision with the lampblack to purify the lampblack. The key to affect the use effect of the water conveyance and gas collecting hood is to form a continuous water curtain, and the circulating water system needs to be cleaned regularly. In fact, due to poor management, most water and gas (smoke) caps will not form a continuous water curtain, but can only form intermittent water droplets or small water columns, which makes them unusable.

三、排煙管道

3、 Smoke exhaust pipe

廚房排氣管的水平段不宜過長。一般情況下，水平距離不應(yīng)超過15米，坡度應(yīng)大于2%。水平端有可移動的接頭，便于機(jī)油。根據(jù)規(guī)范，排氣速度不得小于10m/s，以防止油因低風(fēng)速而粘附在煙道上。連接到排氣罩的支架應(yīng)配備空氣流量控制閥。

The horizontal section of kitchen exhaust pipe should not be too long. Generally, the maximum horizontal distance shall not exceed 15m and the gradient shall be greater than 2%. The horizontal end has a movable joint for easy removal of oil. According to the specification, the exhaust velocity shall not be less than 10m/s to prevent oil from adhering to the flue due to low wind speed. Supports attached to exhaust hoods shall be equipped with air flow control valves.

排煙管的不合理設(shè)計(jì)和安裝往往會導(dǎo)致廚房產(chǎn)生煙氣，直接影響煙氣凈化器的使用。主要原因如下：

The unreasonable design and installation of smoke exhaust pipe will often lead to smoke in the kitchen, which directly affects the use of smoke purifier. The main reasons are as follows:

（1） 主排氣管道通風(fēng)面積不足，氣流較大。根據(jù)工程經(jīng)驗(yàn)，主排氣管內(nèi)的風(fēng)速不超過15m/s。否則，運(yùn)行一段時(shí)間（如一年）后，很容易造成排煙系統(tǒng)堵塞。在油煙凈化器的運(yùn)行實(shí)踐中，大多數(shù)情況下，排煙管因通風(fēng)面積不足而堵塞，管內(nèi)氣體流速大于15m/s。

(1) The ventilation area of the main exhaust pipe is insufficient and the air flow is large. According to engineering experience, the wind speed in the main exhaust pipe shall not exceed 15m/s. Otherwise, after a period of operation (such as one year), it is easy to cause the smoke exhaust system to be blocked. In the operation practice of the oil fume purifier, in most cases, the smoke exhaust pipe is blocked due to insufficient ventilation area, and the gas velocity in the pipe is greater than 15m/s.

（2） 當(dāng)排煙管穿過建筑梁時(shí)，通風(fēng)的橫截面積變小，橫截面積上的阻力增大，從而使氣流順暢。

(2) When the smoke exhaust pipe passes through the building beam, the cross sectional area of ventilation becomes smaller, and the resistance on the cross sectional area increases, thus making the air flow smooth.

（3） 當(dāng)排氣管穿過建筑梁或避開其他設(shè)備管道時(shí)，一段排氣管將低于整個(gè)排氣管的平面。使用一段時(shí)間后，油水混合物會積聚在排氣管的下部，直接影響排氣煙的平滑度。

(3) When the exhaust pipe passes through the building beam or avoids other equipment pipes, a section of exhaust pipe will be lower than the plane of the entire exhaust pipe. After using for a period of time, the oil-water mixture will accumulate in the lower part of the exhaust pipe, which directly affects the smoothness of the exhaust smoke.

（4） 來自不同樓層的廚房煙氣通過同一主管排放。在靠近出口的地板上，廚房的煙比較好，但在較低的廚房里，煙并不順暢。

(4) The kitchen smoke from different floors is discharged through the same main pipe. On the floor near the exit, the smoke in the kitchen is better, but in the lower kitchen, the smoke is not smooth.

四、風(fēng)機(jī)

4、 Fan

1.常用的排風(fēng)機(jī)有三種：軸流風(fēng)機(jī)、風(fēng)柜風(fēng)機(jī)和離心風(fēng)機(jī)。

1. There are three types of exhaust fans in common use: axial flow fan, fan cabinet fan and centrifugal fan.

（1） 軸流風(fēng)機(jī)以前應(yīng)用廣泛，但由于總壓較低，安裝油煙凈化器后很少使用。然而，它通常用于低空油煙凈化器的設(shè)計(jì)和安裝。

(1) Axial flow fan was widely used before, but it was rarely used after installing lampblack purifier due to low total pressure. However, it is usually used for the design and installation of low altitude lampblack purifier.

（2） 風(fēng)柜風(fēng)機(jī)總壓中等，風(fēng)量可調(diào)，噪音低。它通常用于從發(fā)動機(jī)罩到排煙口中等距離的廚房排煙系統(tǒng)。

(2) The total pressure of the fan of the air cabinet is medium, the air volume is adjustable, and the noise is low. It is usually used for kitchen smoke exhaust system with medium distance from engine hood to smoke exhaust outlet.

（3） 離心風(fēng)機(jī)的總壓力和體積可以調(diào)節(jié)，但由于噪音高，通常需要降低噪音。當(dāng)廚房位于建筑物底部時(shí)，其排氣扇應(yīng)放置在屋頂上。一方面可以減少室內(nèi)噪聲污染，同時(shí)排氣管處于負(fù)壓狀態(tài)，避免臭氣外溢。當(dāng)風(fēng)機(jī)放置在屋頂上時(shí)，通常選擇離心式風(fēng)機(jī)。

(3) The total pressure and volume of the centrifugal fan can be adjusted, but because of the high noise, it is usually necessary to reduce the noise. When the kitchen is located at the bottom of the building, its exhaust fan should be placed on the roof. On the one hand, it can reduce indoor noise pollution, and at the same time, the exhaust pipe is in a negative pressure state to avoid odor overflow. When the fan is placed on the roof, centrifugal fan is usually selected.

2.廚房排煙量的測定

2. Measurement of kitchen smoke exhaust

為保證凈化效果，在實(shí)際設(shè)計(jì)中，要求嚴(yán)格按照排氣罩的吸入速度計(jì)算排氣量。發(fā)動機(jī)罩的吸氣速度一般不小于0.5m/s。

In order to ensure the purification effect, in the actual design, it is required to calculate the exhaust volume in strict accordance with the suction speed of the exhaust hood. The suction speed of the engine hood is generally not less than 0.5m/s.

五、油煙凈化器

5、 Oil fume purifier

1.處理空氣流量的測量：

1. Measurement of treatment air flow:

靜電油煙凈化器處理風(fēng)量的確定一般有三個(gè)主要依據(jù)：一是根據(jù)排風(fēng)罩投影面積計(jì)算排風(fēng)量；另一個(gè)是爐子的數(shù)量；一個(gè)是從匹配的吸入柜中抽出的空氣量。

Generally, there are three main bases for determining the air volume to be handled by the electrostatic lampblack purifier: first, calculate the air volume according to the projected area of the exhaust hood; The other is the number of furnaces; One is the amount of air pumped from the matched suction cabinet.

1）根據(jù)集油煙罩總投影面積（S）選型：處理風(fēng)量=S（m2）×2500≤油煙凈化器量。

1) Model selection according to the total projected area (S) of the oil collecting hood: treated air volume=S (m2) × 2500 ≤ oil smoke purifier volume.

2） 根據(jù)爐子的選擇：

2) According to the choice of furnace:

每個(gè)標(biāo)準(zhǔn)爐（φ=350mm），風(fēng)量2000m3/h，總處理風(fēng)量=爐數(shù)×2000m3/h，然后根據(jù)總風(fēng)量確定設(shè)備型號。

Each standard furnace（ φ= 350mm), air volume 2000m3/h, total treated air volume=number of boilers × 2000m3/h, and then determine the equipment model according to the total air volume.

3） 根據(jù)原風(fēng)機(jī)匹配選擇：所選凈化器型號與原風(fēng)機(jī)風(fēng)量匹配。

3) Selection according to the matching of the original fan: the selected purifier model matches the air volume of the original fan.

4） 根據(jù)匹配的風(fēng)扇進(jìn)行選擇

4) Select according to the matching fan

（1） 計(jì)算系統(tǒng)管網(wǎng)壓力損失：系統(tǒng)管網(wǎng)壓力損失包括局部壓力損失和沿途壓力損失。局部壓力損失：每個(gè)減壓器、彎頭、入口和出口的壓力損失

(1) Calculation of system pipe network pressure loss: system pipe network pressure loss includes local pressure loss and pressure loss along the way. Local pressure loss: pressure loss of each reducer, elbow, inlet and outlet

沿途壓力損失：直線段壓力損失

Pressure loss along the way: pressure loss in straight section

（2） 風(fēng)機(jī)總壓力=（管網(wǎng)壓力損失+設(shè)備壓力損失）×（100+20）%

(2) Total fan pressure=(pipe network pressure loss+equipment pressure loss) × （100+20）%

根據(jù)風(fēng)機(jī)的總壓力選擇風(fēng)機(jī)的類型和規(guī)格

Select the type and specification of the fan according to the total pressure of the fan

風(fēng)機(jī)額定容量=復(fù)合煙氣凈化器總處理量×1.2%

Rated capacity of fan=total treatment capacity of composite flue gas purifier × 1.2%

5）蔬菜產(chǎn)生的揮發(fā)性油煙較大，凈化器的設(shè)計(jì)容量應(yīng)增加40%

5) The volatile oil fume produced by vegetables is large, and the design capacity of the purifier should be increased by 40%