怎麼提高生物質熱風爐運行效率

隨著科學技術成都收賬進步,我國工業熱風爐廣泛使用瞭設計效率達80%左右成都找人公司鏈條爐,其運行狀況如何呢?筆者參與瞭大部分地區部分熱風爐成都收賬熱工測試及調研工作,總收賬印象是大型熱風爐運行狀況尚可,小型熱風爐運行狀況並不理想,小型熱風爐運行中普遍存在著過剩空氣系數大,排煙溫度及灰渣含碳量高等問題,使熱風爐運行效率比設計效率低10% ~15%。解決這一問題成都找人公司根本出路是采用集中供熱取代這些分散小型熱風爐。當務之急,應采取以下措施。
With the progress of science and technology, chain stoves with design efficiency of about 80% have been widely used in industrial hot stoves in China. How about their operation? The author participated in the thermal test and investigation of some hot stoves in most areas. The general impression is that the operation of large hot stoves is still acceptable, the operation of small hot stoves is not ideal and small ones. The problems of high excess air coefficient, high exhaust gas temperature and high carbon content in ash and slag generally exist in the operation of hot blast stove, which make the operation efficiency of hot blast stove 10% to 15% lower than the design efficiency. The fundamental solution to this problem is to replace central heating with these small hot blast stoves. Urgent measures should be taken.
1、合理控制過剩空氣系數 鏈條成都找人公司排煙過剩空氣系數經濟值在1.6~1.9之間,而實測過剩空氣系數幾乎都大於2,個別超過3。而過剩空氣系數增加0.1約使排煙損失增加0.7%,由此造成瞭排煙熱損失大大增加。 過剩空氣系數大的原因在於小型成都***都未裝設必要的監測儀表,燃燒調節缺乏科學性,司爐僅憑“經驗”進行。 合理控制過剩空氣系數首先應配置奧氏儀和U型管壓力計。壓力計用於測量鼓、引風機的壓力、風室壓力、煙道各段阻力變化情況以及爐膛負壓,配合煙氣分析調整成都***的燃燒。一般應使爐膛出口保持-2~-3毫米水柱的壓力,排煙含氧量8%~10%。司爐應懂得送風量大,增加瞭空氣量對燃燒有利,但降低瞭爐膛溫度對燃燒不利,且還會導致排煙熱損失q2增大,而經濟的過剩空氣系數可使各項損失之和為最小,熱風爐效率為最高。 對運行中的熱風爐來講,若熱風爐雙側進風燃燒中出現瞭爐排中間旺甚至穿孔的現象時,以及單側進風的熱風爐出現瞭一邊紅一邊黑的“陰陽爐”現象時,都是配風不均勻造成的。側密封漏風、出渣口漏風是熱風爐密封欠佳的主要表現。側密封漏風還會形成小區域燃燒導致鏈條燒壞。 對以上問題我們應采取以下措施:
1. Reasonable control of excess air coefficient The economic value of excess air coefficient of exhaust gas in chain hot blast stove ranges from 1.6 to 1.9, while the measured excess air coefficient is almost greater than 2, and some exceed 3. The excess air coefficient increases by about 0.1, which increases the smoke loss by 0.7%, resulting in a significant increase in the heat loss of smoke. The reason for the high excess air coefficient is that the small hot blast stoves are not equipped with necessary monitoring instruments, and the combustion regulation is not scientific, so the stoves are only carried out by "experience". Reasonable control of excess air coefficient should first be equipped with Ordovician and U tube manometer. Pressure gauge is used to measure the pressure of blower and induced draft fan, chamber pressure, resistance change of flue duct and furnace negative pressure, and adjust the combustion of hot blast stove with flue gas analysis. Generally, the furnace outlet should maintain the pressure of -2~-3 mm water column and the oxygen content of the exhaust gas will be 8%~10%. Furnace managers should understand that large air supply and increased air volume are beneficial to combustion, but lowering furnace temperature is not conducive to combustion, and will also lead to an increase in exhaust heat loss q2. Economic excess air coefficient can minimize the sum of all losses, and the efficiency of hot blast stove is the highest. For the hot blast stove in operation, the uneven distribution of air is caused by the phenomena of strong or even perforation in the middle of the grate during the combustion of both sides of the hot blast stove and the phenomenon of "Yin-Yang stove" with red side and black side in the one side of the hot blast stove. The leakage of the side seal and the leakage of the slag outlet are the main manifestations of the poor sealing of the hot blast stove. The air leakage in the side seal will also cause small area combustion to cause the chain to burn out. For the above problems, we should take the following measures:
(1)在保證各個風室之間基本密封的前提下對燃燒區的幾個風室加設開孔節流隔板,實踐證明一個風室內宜裝4~5塊隔板,開孔面積視實際情況而定。該法對改善風壓分佈的不均勻性有明顯的作用。例如某廠10噸/時鏈條爐,燃燒中經常出現“陰陽爐”現象,司爐為瞭降低灰渣含碳量,不得不加大送風量,結果偏燒現象更嚴重,曾出現過燒壞側密封和夾板拉緊螺桿等現象,而不得不停爐檢修。改造時在第二、三、四分風室各加五塊開孔節流隔板,將風室分隔成六個風壓各相等的隔倉,使單側進風時風壓分佈沿爐排寬度方向基本均勻。測試爐渣含碳量降低3%,排煙熱損失降低1%,印花地坪熱風爐效率提高2%。偏燒問題解決瞭, 再也沒發生過事故停爐現象。
(1) On the premise of guaranteeing the basic sealing between the air chambers, the opening and throttling baffles are added to several air chambers in the combustion zone. Practice has proved that 4-5 baffles should be installed in one air chamber, and the opening area depends on the actual situation. This method has obvious effect on improving the inhomogeneity of wind pressure distribution. For example, in a 10 ton/h chain grate furnace, the phenomenon of "Yinyang furnace" often occurs in combustion. In order to reduce the carbon content of ash and slag, the furnace has to increase the air supply. As a result, the phenomenon of partial burning is more serious. Some phenomena such as burning out side seals and splint tensioning screw have occurred, and the furnace has to stop for maintenance. Five orificed throttle baffles were added to the second, third and fourth air compartments, and the air compartments were divided into six compartments with equal air pressure, so that the distribution of air pressure along the width direction of the grate was basically uniform when one side of the air inlet was used. The carbon content of the slag is reduced by 3%, the heat loss of the exhaust gas is reduced by 1%, and the efficiency of the hot stove is increased by 2%. The problem of partial combustion has been solved, and no accident has stopped.
(2)加大爐排風室入口截面尺寸,這樣可降低風室入口處氣流速度,減少由於氣流進入風室,截面突擴產生的渦流,使風室內風壓相對均勻。該法受熱風爐結構限制,僅能在配風不勻表現不十分明顯時使用。
(2) Enlarging the cross-section size of the entrance of the exhaust chamber can reduce the air velocity at the entrance of the chamber, reduce the eddy current caused by the sudden expansion of the cross-section, and make the air pressure in the chamber relatively uniform. The method is restricted by the structure of the hot blast stove and can only be used when the air distribution is uneven.
(3)實際上,迷宮式側密封易漏風,對經濟條件差的用戶應考慮采用“灰漿水泥堵漏法”予以補救,該法密封效果好、經濟實惠,改造周期短。也可以考慮將側密封
(3) In fact, labyrinth side seals are easy to leak. Users with poor economic conditions should consider using "mortar cement plugging method" to remedy the leak. This method has good sealing effect, economic benefits and short transformation period. The side seal can also be considered. 所謂生物質熱風爐的經濟運行，就是指用最低的成本，使熱風爐發揮最大的作用。熱風爐的運行成本主要包括：燃料費用、水費、電費和人員的工資等等。其中燃料費用所占比重最大，如果能夠有效地提高熱風爐的熱效率，就能更好地控制熱風爐的運行成本，提高熱風爐的運行水平。
The so-called economic operation of biomass hot-blast stoves means that the hot-blast stoves play the greatest role with the lowest cost. The running cost of hot blast stove mainly includes: fuel cost, water charge, electricity fee and personnel's wages. Among them, fuel cost accounts for the largest proportion. If the thermal efficiency of hot-blast stove can be effectively improved, the operation cost of hot-blast stove can be better controlled and the operation level of hot-blast stove can be improved.
控制熱風爐燃料消耗量，可以從以下幾個方面考慮：
Controlling the fuel consumption of hot blast stove can be considered from the following aspects:
（1）生物質熱風爐的燃料選擇熱風爐使用的燃料熱值應盡量與設計燃料熱值接近。如果熱值不一致，就會導致熱風爐出口力不足或不能在最佳工作點運行，無形之中會降低熱風爐熱效率或損壞設備。所以購買燃料時，應首先知道燃料的種類和熱值，必要時應采樣化驗燃料。
(1) The fuel calorific value of biomass hot blast stove should be as close as possible to that of design fuel. If the calorific value is inconsistent, it will result in insufficient outlet force or failure to operate at the optimum working point. Invisibly, it will reduce the thermal efficiency of hot stove or damage equipment. So when buying fuel, we should first know the type and calorific value of fuel, and when necessary, we should sample and test fuel.
（2）用熱部門提前與鍋護房聯系用熱部門在其所需負荷有較大變動時，應提前與熱風爐房聯系。便於對熱風爐有序地進行負荷調節，以保證熱風爐運行在一個較經濟的工作點上。
(2) The heating Department should contact the hot blast stove house in advance when the required 彩色沥清地坪load of the heating Department varies greatly. It is convenient to regulate the load of the hot stove in order to ensure that the hot stove runs at a more economical working point.
（3）采暖熱風爐的負荷調整在冬季，环境的最高與最低氣溫相差很大。這就要求采暖熱風爐根據环境溫度的高低，調整熱風爐供熱量的大小。調整方式可采用質調節或量調節，隻要能夠保證采暖要求即可，最忌運行狀態一成不變。
(3) the load adjustment of heating stove is very different in winter. This requires that the heating stove adjust the heating capacity of the hot stove according to the temperature of the environment. Adjustment mode can adopt quality regulation or quantity regulation, as long as the heating requirements can be guaranteed, the most taboo operation status remains unchanged.