脱硫催化剂在脱硫过程中的作用及关系

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脱硫催化剂在脱硫过程中的作用及关系。脱硫催化剂作为脱硫液组成的核心，维持稳定的催化剂浓度和碱度是十分重要的事情，作为以Na2CO3为碱源的脱硫，控制PH8~8.5时，作为缓冲溶液的当量浓度控制不能过低也不能太高。过低不利于吸收脱硫效率低，再*浮选差且泡沫细不成型，长期过低，容易导致组分失调，低于0.3时提碱度十分困难。脱硫生产过程副反应的产生是不可避免的，应采用脱硫催化剂以减少副反应的生成。一般认为副盐总量≤200g/L是能够维持正常生产。若副反应严重时，碱耗剧增，大量补碱也难以维持碱度。当溶液中副盐总量很高时，溶液粘度、比重增加，动力消耗增加，甚至出现循环泵不打液。严重影响吸收和再*。当溶液中Na2SO4≥80g/L时，设备腐蚀加剧，硫回收率降低，温度低时非常容易结晶堵塞管道或堵塔，脱硫工况出现紊乱，HS-的析硫速度和程度决定于合理的脱硫液组分、催化剂的**等因素，我们公司结合沼气脱硫的气体成分和工况特点研发了沼气脱硫专用催化剂。

Role and relationship of desulfurization catalyst in desulfurization process. Desulfurization catalyst is the core of the composition of desulfurization solution. It is very important to maintain stable catalyst concentration and alkalinity. As desulfurization with Na2CO3 as alkali source, when controlling pH8 ~ 8.5, the equivalent concentration of buffer solution should not be too low or too high. Too low is not conducive to absorption and desulfurization, and the re flotation is poor and the foam is not formed. If it is too low for a long time, it is easy to cause component imbalance, and it is very difficult to increase the alkalinity below 0.3. The generation of side reactions in desulfurization production process is inevitable. Desulfurization catalyst should be used to reduce the generation of side reactions. It is generally believed that the total amount of by-salt ≤ 200g / l can maintain normal production. If the side reaction is serious, the alkali consumption will increase sharply, and it is difficult to maintain the alkalinity with a large amount of alkali supplement. When the total amount of secondary salt in the solution is very high, the viscosity and specific gravity of the solution increase, the power consumption increases, and even the circulating pump does not pump liquid. Seriously affect absorption and reabsorption *. When Na2SO4 in the solution is ≥ 80g / L, the equipment corrosion intensifies, the sulfur recovery rate decreases, it is very easy to crystallize and block the pipeline or tower at low temperature, and the desulfurization working condition is disordered. The sulfur evolution speed and degree of HS - depend on the reasonable desulfurization liquid composition, catalyst * * and other factors. Our company has developed a special catalyst for biogas desulfurization in combination with the gas composition and working condition characteristics of biogas desulfurization.

针对沼气气体含有较高二氧化碳的工况，硫化氢和二氧化碳都是酸性气体，碱性溶液选择性吸收酸性气体的困难增加，并且会有大量的碳酸氢钠产生，降低碳酸钠的吸收**。沼气是高CO2气体工况，作为以Na2CO3为碱源制备的脱硫液，在脱硫塔内除了完成了Na2CO3和H2S的吸收过程，同时也完成了Na2CO3和CO2生成NaHCO3的反应过程。作为缓冲溶液，高NaHCO3的脱硫液虽然能够脱除H2S，但是脱硫效率明显下降。更为严重的情况是脱硫液分析竟然Na2CO3含量为零。NaHCO3指标50-60g/L也屡见不鲜。这时要采取积极措施调节NaHCO3/ Na2CO3之比也可暂时往系统补NaOH来调节NaHCO3(比较快速)。笔者认为对于NaHCO3和Na2CO3的调节好通过生产过程的管理，来实现其自身平衡。沼气脱硫工况对脱硫催化剂的要求更高了。这几年，我们公司针对具体的沼气脱硫的特点及工况，研发了适合沼气脱硫的专用催化剂，具有脱硫效率高，硫容高，副反应少，溶液组分简单易操作，不易堵塔等特点，更低消耗更高催化效率服务于沼气脱硫等。
Under the condition that biogas gas contains high carbon dioxide, hydrogen sulfide and carbon dioxide are acid gases. It is more difficult for alkaline solution to selectively absorb acid gases, and a large amount of sodium bicarbonate will be produced, reducing the absorption of sodium carbonate. Biogas is a high CO2 gas working condition. As a desulfurization solution prepared with Na2CO3 as alkali source, it not only completes the absorption process of Na2CO3 and H2S, but also completes the reaction process of Na2CO3 and CO2 to generate NaHCO3 in the desulfurization tower. As a buffer solution, although the desulfurization solution with high NaHCO3 can remove H2S, the desulfurization efficiency decreases significantly. The more serious situation is that the content of Na2CO3 in desulfurization solution is zero. NaHCO3 index of 50-60g / L is also common. At this time, active measures should be taken to adjust the ratio of NaHCO3 / Na2CO3, or NaOH can be added to the system temporarily to adjust NaHCO3 (relatively fast). The author believes that the adjustment of NaHCO3 and Na2CO3 can achieve their own balance through the management of production process. The requirements for desulfurization catalyst under biogas desulfurization conditions are higher. In recent years, according to the specific characteristics and working conditions of biogas desulfurization, our company has developed a special catalyst suitable for biogas desulfurization, which has the characteristics of high desulfurization efficiency, high sulfur capacity, less side reactions, simple solution components, easy operation and not easy to block the tower, lower consumption and higher catalytic efficiency to serve biogas desulfurization.