在整个湿法脱硫过程中，从吸收到再生，再到硫回收，有些工艺条件是相互矛盾的。新设计的脱硫装置一般都会综合考虑到各种相互影响的因素，把系统的脱硫、再生、以及硫回收做为一个系统工程，全面考虑，统筹解决。但是，对于不断进行扩产改造或者是利用旧设备的装置，常常存在着各种不相匹配的因素，所以需要正确认识，合理兼顾这些指标。
In the whole wet desulfurization process, some process conditions are contradictory from absorption to regeneration and then to sulfur recovery. Generally, the newly designed desulfurization unit will comprehensively consider various interactive factors, and take the desulfurization, regeneration and sulfur recovery of the system as a systematic project, comprehensively consider and solve it as a whole. However, there are often various mismatched factors for the continuous expansion and transformation of production or the use of old equipment, so we must correctly understand and give reasonable consideration to these indicators.
1 吹风强度与再生空气量
1. Blowing intensity and regeneration air volume
我们知道，再生的作用有几点。一，供给脱硫所需要的化学反应的氧量。二，富液中的HS-在再生时继续被氧化，同时恢复催化剂的活性。三，在空气的鼓泡和吹搅下，硫粒聚集成硫泡沫浮在上面，便于浮选把硫黄分离出去。第四，把溶液中在脱硫的同时被吸收的CO2气提出去，从而提高溶液碱度，降低碱的消耗。由此可知，如果单纯从再生角度出发，吹风强度越大，再生越完全、越彻底。但是，过大的吹风强度却会对硫泡沫的正常浮选带来不利影响。过大的空气量会造成液面翻腾较大，硫泡沫层不稳定，硫浮选分离差，造成悬浮硫高。若空气量长期过大，则溶液电位将偏高，会使副反应加快。过度氧化还会造成硫酸钠的升高，带来设备腐蚀。所以，再生槽的吹风强度要适宜，一般喷射再生流程的吹风强度为60m3/m2.h～100m3/m2.h。各企业在生产实践中，可以根据自身的设备和工艺状况，摸索出适合自己工况的佳空气量。
We know that regeneration has several functions. First, supply the oxygen for the chemical reaction required for desulfurization. Second, HS - in the rich liquid continues to be oxidized during regeneration and restores the activity of the catalyst. Third, under the bubbling and stirring of air, sulfur particles gather into sulfur foam and float on it, which is convenient for flotation to separate sulfur. Fourth, the CO2 gas absorbed in the solution while desulfurization is carried out, so as to improve the alkalinity of the solution and reduce the consumption of alkali. It can be seen from this that the greater the blowing intensity is, the more complete and thorough the regeneration is if only from the perspective of regeneration. However, excessive blowing intensity will bring adverse effects on the normal flotation of sulfur foam. Excessive air volume will cause large liquid level churning, unstable sulfur foam layer and poor sulfur flotation separation, resulting in high suspended sulfur. If the air volume is too large for a long time, the solution potential will be high, which will accelerate the side reaction. Excessive oxidation will also cause the rise of sodium sulfate and equipment corrosion. Therefore, the blowing intensity of the regeneration tank should be appropriate. Generally, the blowing intensity of the jet regeneration process is 60m3 / m2 h～100m3/m2. h。 In production practice, enterprises can find out the best air volume suitable for their own working conditions according to their own equipment and process conditions.
2 溶液循环量与再生停留时间
2 solution circulation volume and regeneration residence time
溶液的循环量与再生停留时间是反比关系。在其它条件不变的情况下，当气量大，H2S含量高时，为保证脱硫效率，应适当增加溶液循环量，即增大液气比和喷淋密度。但是，在增加循环量的同时，一定要考虑溶液在再生槽中的停留时间。否则，因为循环量的增加，缩短了溶液在再生槽的停留时间，造成再生不完全，溶液质量差，同样达不到较高的脱硫效率。以前我公司做过一个方案，脱硫塔直径为φ4800，原有的贫液泵额定流量为420m3/h，其喷淋密度20m3/m2.h多，明显偏小了。所以，必须增加溶液的循环量。如果单纯从喷淋密度考虑，以增加至800 m3/h为佳，此时喷淋密度为44 m3/m2.h。但是该厂再生槽容积是为循环量400 m3/h左右而设计，如果流量增加至800 m3/h，则溶液在再生槽中的停留时间太短，无法满足再生需求，再生槽容积肯定要做相应调整，这样就给施工带来很大的工作量。考虑到该厂脱硫塔进口硫含量不高，脱硫负荷不大，所以，建议把流量增加到600 m3/h，这样喷淋密度为33 m3/m2.h，基本能满足要求，而且，该流量下再生槽内溶液的停留时间为12分钟。
The circulation amount of solution is inversely proportional to the regeneration residence time. When other conditions remain unchanged, when the gas volume is large and the H2S content is high, in order to ensure the desulfurization efficiency, the solution circulation volume should be appropriately increased, that is, the liquid-gas ratio and spray density should be increased. However, while increasing the circulation volume, the residence time of the solution in the regeneration tank must be considered. Otherwise, the residence time of the solution in the regeneration tank is shortened due to the increase of the circulation volume, resulting in incomplete regeneration and poor solution quality, which also can not achieve high desulfurization efficiency. Our company has made a scheme before, and the diameter of desulfurization tower is φ 4800, the rated flow of the original lean solution pump is 420m3 / h, and its spray density is 20m3 / m2 H is too much, which is obviously too small. Therefore, the circulation amount of solution must be increased. If only considering the spray density, it is better to increase to 800 m3 / h, and the spray density is 44 m3 / m2 h。 However, the volume of the regeneration tank in the plant is designed for the circulation volume of about 400 m3 / h. If the flow increases to 800 m3 / h, the residence time of the solution in the regeneration tank is too short to meet the regeneration demand. The volume of the regeneration tank must be adjusted accordingly, which will bring a lot of work to the construction. Considering that the sulfur content at the inlet of the desulfurization tower of the plant is not high and the desulfurization load is small, it is recommended to increase the flow to 600 m3 / h, so that the spray density is 33 m3 / m2 h. Basically meet the requirements, and the residence time of the solution in the regeneration tank under this flow is 12 minutes.
溶液循环量与再生空气量也有着密切关系。因为喷射氧化再生槽的工艺，是靠富液通过喷射器吸入空气的，而富液吸入空气量基本上是恒定的。如果循环量太小，则吸入空气量不足，可能就满足不了再生氧化槽所需的空气量，就可能开车后不久出现再生效果不理想、悬浮硫高、硫回收率低、吸收剂与催化剂消耗高等问题，严重时还会引起堵塔。
The amount of solution circulation is also closely related to the amount of regeneration air. Because the process of spraying oxidation regeneration tank depends on the rich liquid to inhale air through the ejector, and the amount of air inhaled by the rich liquid is basically constant. If the circulation volume is too small, the intake air volume is insufficient, which may not meet the air volume required by the regenerative oxidation tank. Soon after start-up, there may be problems such as unsatisfactory regeneration effect, high suspended sulfur, low sulfur recovery rate, high consumption of absorbent and catalyst, and even tower blockage.
3 溶液总碱度与PH值
3 total alkalinity and pH value of solution
溶液的总碱度与其硫容量成正比关系，因此，提高总碱度是提高硫容量的有效途径。换句话说，中和反应过程中，在其它工况不变的情况下，提高总碱度可以更好的保证脱硫效率。但是，若总碱度过高，原料消耗增加且副反应加快。
The total alkalinity of the solution is directly proportional to its sulfur capacity. Therefore, increasing the total alkalinity is an effective way to improve the sulfur capacity. In other words, in the process of neutralization reaction, increasing the total alkalinity can better ensure the desulfurization efficiency under the condition that other working conditions remain unchanged. However, if the total alkalinity is too high, the consumption of raw materials will increase and the side reactions will accelerate.
PH值是脱硫液的基本指标，PH值太低，不利于硫化氢的吸收，并会降低氧的溶解度，溶液再生效果差；PH值太高，会加快副反应，副盐生成率高，影响析硫速度，硫回收差，且增加碱耗。
PH value is the basic index of desulfurization solution. Too low pH value is not conducive to the absorption of hydrogen sulfide, will reduce the solubility of low oxygen, and the regeneration effect of solution is poor; If the pH value is too high, the side reaction will be accelerated, the generation rate of side salt will be high, the sulfur separation speed will be affected, the sulfur recovery will be poor, and the alkali consumption will be increased.
至于总碱度与PH值的关系，一般来说，PH值随总碱度的增加而上升，但严格的讲，PH值主要是受NaHCO3/ Na2CO3的影响，PH与比值呈反比关系，还有就是硫酸根离子的影响。
As for the relationship between total alkalinity and pH value, generally speaking, pH value increases with the increase of total alkalinity, but strictly speaking, pH value is mainly affected by NaHCO3 / Na2CO3, pH is inversely proportional to the ratio, and there is the influence of sulfate ion.
在实际生产中，由于各厂情况不同，脱硫进口气体中H2S含量差别较大，工艺与设备配置的合理性也有很大差异，因此，对于总碱度的控制原则和指导思想应该是：在保证适宜溶液循环量和较高脱硫效率的前提下，保证出口硫化氢，溶液的总碱度控制在低限，降低生产消耗和副反应物的生成，从而保持工况的稳定。
In the actual production, due to the different conditions of each plant, the H2S content in the desulfurization inlet gas varies greatly, and the rationality of process and equipment configuration also varies greatly. Therefore, the control principle and guiding ideology for the total alkalinity should be: on the premise of ensuring the appropriate solution circulation and high desulfurization efficiency, ensure the outlet hydrogen sulfide, control the total alkalinity of the solution at the low limit, and reduce the production consumption and the generation of side reactants, So as to maintain the stability of working conditions.
4 重视分析工作
4 attach importance to analysis
分析数据是我们的眼睛，我们合理调整消耗以及指导工作的依据，所以建立、完善、规范脱硫分析，从而更好利用这些分析数据指导生产，保证生产连续稳定的运行。
The analysis data is our eyes. We reasonably adjust the consumption and guide the work, so we establish, improve and standardize the desulfurization analysis, so as to make better use of these analysis data to guide the production and ensure the continuous and stable operation of the production.
The above is about biogas purification. I hope it will help you If you have any questions, please contact us We will provide you with professional service https://www.hneee.net
企业二维码
2022-05-10
鲁公网安备37011202000764号号