沸石轉輪濃縮VOCs凈化技術是利用沸石分子篩吸附劑對排放廢氣中的VOCs進行吸附凈化的技術。沸石分子篩是結晶硅鋁酸鹽，以其規(guī)整的晶體結構、均勻一致的孔分布和可調變的表面性質在VOCs廢氣治理領域得到廣泛應用。沸石轉輪是大多數涂裝企業(yè)在治理VOCs過程中必不可少的系統(tǒng)部件，主要用于大風量低濃度的VOCs廢氣富集。

The zeolite rotary wheel concentration VOCs purification technology is a technology that uses zeolite molecular sieve adsorbents to adsorb and purify VOCs in exhaust gas emissions. Zeolite molecular sieve is a crystalline aluminosilicate, widely used in the field of VOCs waste gas treatment due to its regular crystal structure, uniform pore distribution, and adjustable surface properties. Zeolite wheel is an essential system component in the treatment of VOCs in most coating enterprises, mainly used for the enrichment of high air volume and low concentration VOCs waste gas.

一、沸石轉輪的工作原理

1、 The working principle of zeolite wheel

眾所周知，沸石轉輪面在物理區(qū)間被分為吸附區(qū)、脫附區(qū)、冷卻區(qū)域，各區(qū)域比例為10:1:1，分區(qū)圖下圖所示：

As is well known, the zeolite wheel surface is divided into adsorption zone, desorption zone, and cooling zone in the physical range, with a ratio of 10:1:1 for each zone. The zoning diagram is shown in the following figure:

大風量低濃度的VOCs經過沸石轉輪后，由于分子之間的范德華力，VOCs被沸石微孔所吸附，凈化后的氣體可直接排至排氣筒。被吸附在沸石轉輪上的有機物再通過一小股180℃～200℃的溫度的氣體進行脫附。脫附出來的高濃度廢氣再送入其他設備進行處理，從而降低了末端處理設備的負荷，降低了運行能耗，被廣泛使用在噴涂行業(yè)、包裝行業(yè)、電子半導體行業(yè)。

After the high air volume and low concentration VOCs pass through the zeolite impeller, due to the van der Waals forces between molecules, VOCs are adsorbed by the zeolite micropores, and the purified gas can be directly discharged into the exhaust pipe. The organic matter adsorbed on the zeolite wheel is then desorbed through a small stream of gas at a temperature of 180 ℃ to 200 ℃. The high concentration waste gas desorbed is sent to other equipment for treatment, thereby reducing the load of the end treatment equipment and reducing operational energy consumption. It is widely used in the spray coating industry, packaging industry, and electronic semiconductor industry.

二、吸附脫附性能及改善措施

2、 Adsorption and desorption performance and improvement measures

轉輪按設定的速度轉動，實現了廢氣的循環(huán)吸附脫附。然而對于廢氣成分復雜，含有高沸點的有機物，往往180℃-200℃的溫度不足以將有機物脫附出來，這些高沸點有機物殘留在沸石的孔隙中，隨著時間的推移，殘留的累積量越來越多，可用于吸脫附的孔隙越來越少，終導致轉輪出口有機物濃度偏高，排放不達標現象。因此，必須采取一定的措施，將高沸點組分從沸石中脫附出來，恢復轉輪的吸附容量。

The wheel rotates at the set speed to achieve the cyclic adsorption and desorption of waste gas. However, for exhaust gases with complex components and high boiling point organic compounds, temperatures between 180 ℃ and 200 ℃ are often insufficient to desorb the organic compounds. These high boiling point organic compounds remain in the pores of zeolites, and over time, the accumulated amount of residues increases. The number of pores available for adsorption and desorption decreases, ultimately leading to a high concentration of organic compounds at the outlet of the impeller and substandard emissions. Therefore, certain measures must be taken to desorb high boiling components from the zeolite and restore the adsorption capacity of the impeller.

無論是哪種沸石轉輪，廠商一般會建議周期性對轉輪進行高溫再生。如：將脫附溫度設定為300℃，進行高溫再生。然而，高溫再生時轉輪處在一個高溫、高濃度的環(huán)境中，安全風險級別也非常高。常規(guī)做法是配備專業(yè)技術人員至現場操作、監(jiān)控高溫再生過程，并根據轉輪及系統(tǒng)相關實際運行數據以及實踐經驗，實時手動調整運行參數或采取應急措施。顯然，這樣的操作，效率低下，對專業(yè)技術人員的依賴程度較高。因此，將沸石濃縮轉輪手動高溫再生操作，轉換成自動程序控制，顯得尤為迫切。

Regardless of the type of zeolite impeller, manufacturers generally recommend periodic high-temperature regeneration of the impeller. For example, set the desorption temperature to 300 ℃ for high-temperature regeneration. However, during high-temperature regeneration, the impeller is in a high-temperature, high concentration environment, and the safety risk level is also very high. The conventional approach is to equip professional technical personnel to operate and monitor the high-temperature regeneration process on site, and manually adjust operating parameters or take emergency measures in real time based on the actual operating data and practical experience of the impeller and system. Obviously, such operations are inefficient and rely heavily on professional technicians. Therefore, it is particularly urgent to convert the manual high-temperature regeneration operation of the zeolite concentration wheel into automatic program control.

三、高溫熱脫附控制邏輯設計

3、 Design of High Temperature Thermal Desorption Control Logic

轉輪高溫熱脫附分兩種模式，分別為“在線式”和“離線式”。

There are two modes for high-temperature desorption of the impeller, namely "online" and "offline".

“離線式”：高溫再生時，轉輪停止轉動，脫附入口溫度從200℃按一定的梯度逐步升溫至300℃。高溫脫附結束后，將轉輪再生干凈的區(qū)域轉至冷卻區(qū)，同時將含有高沸點的待脫附區(qū)域轉入脫附區(qū)。根據以上原則，并結合轉輪分區(qū)10:1:1的特點，可計算出轉輪待高溫再生區(qū)域送入轉輪再生區(qū)域所要的運轉時間。如：假設轉輪50HZ運行，轉1圈需要15min,因此從吸附區(qū)轉至脫附區(qū)，轉輪轉動1次理論所需要的時間為：15min/(10+1+1)×60s/min=75s。但為保證各區(qū)域均能完全高溫再生，轉輪相鄰兩次高溫再生面足夠的搭接長度，同時兼顧轉輪脫附區(qū)隔板保溫厚度的影響，選取轉輪每次連續(xù)轉動時間為60s，此處稱為步長為60s。

Offline mode: During high-temperature regeneration, the rotor stops rotating and the desorption inlet temperature gradually increases from 200 ℃ to 300 ℃ in a certain gradient. After the high-temperature desorption is completed, transfer the clean area regenerated by the impeller to the cooling zone, and at the same time, transfer the area containing high boiling points to the desorption zone. Based on the above principles and combined with the characteristics of the 10:1:1 partition of the impeller, the operating time required for the impeller to be sent into the high-temperature regeneration area can be calculated. For example, assuming the wheel runs at 50HZ and takes 15 minutes to complete one revolution, the theoretical time required for the wheel to rotate once from the adsorption zone to the desorption zone is: 15 minutes/(10+1+1) × 60s/min=75s. However, in order to ensure complete high-temperature regeneration in all areas, there is sufficient overlap length between the two adjacent high-temperature regeneration surfaces of the impeller, while taking into account the influence of the insulation thickness of the separator in the detachment zone of the impeller, a continuous rotation time of 60 seconds is selected for each rotation of the impeller, which is referred to as a step length of 60 seconds.