PRACTICABILITY OF FLAME ARRESTER FOR PETROLEUM REFINING AND PETROCHEMICAL PLANT

对陶瓷避雷器和金属丝网避雷器的火焰熄灭特性进行了实验研究，设计了避雷器的布置位置。对于陶瓷避雷器的火焰熄灭特性，采用丙烷-空气体系中火焰通过避雷器时的最小火焰速度来评价其熄灭能力。在此临界速度下，陶瓷避雷器与不锈钢卷带式避雷器相比具有较好的淬火能力。当量直径和当量长度是影响阻尼器火焰熄灭能力的重要参数，尤其是当量直径小于2 mm的阻燃器，随着厚度的增加，火焰熄灭能力显著增强。不存在材料效应，但表面粗糙度对淬火能力有影响，并讨论了制动器位置对火焰淬火特性的影响。在弯曲区，火焰速度会加快，因此不宜在弯曲区或在弯曲区的正后方设置阻尼器。由于火焰传播过程中火焰温度升高，因此避雷器应设置在较短的行程长度内。当火焰向下传播时，火焰通常在避雷器处停滞，有时停滞的火焰经过一定的停滞时间后通过。在这种情况下，临界速度不是评价避雷器淬火能力的良好指标。因此，阻尼器不应设置在火焰向下传播的地方。

Experiments were conducted on flame quenching characteristic of ceramic type arrester and on wire gauze type arrester to design arrester set up position.For flame quenching characteristic of ceramic type arrester, it was shown that quenching ability was evaluated by the minimum flame velocity at which the flame passed through the arrester in propane-air system. With this critical velocity, good quenching ability was obtained for ceramic arrester compared with stainless steel crimped ribbon type arrester. Equivalent diameter and the length were important parameters, in flame quenching ability of these arresters especially for the arrester with smaller size of equivalent diameter than 2 mm, flame quenching ability increased with increase of the thickness remarkably. There were no material effect but surface roughness effect on quenching ability was obtained.The effect of position of arrester on flame quenching characteristic was also discussed. At curved region in piping flame velocity would be accelerated, and therefore arrester should not set up at curved region or just behind there. Because along with the flame propagation the flame temperature was increased, the arrester should be set up within short run up length. When the flame propagates downward, the flame often stagnates at the arrester, and some times the stagnated flame passed through after a certain stagnation time. In this case, the critical velocity is not a good factor to evaluate the quenching ability of arrester. Therefore, the arrester should not set up where the flame propagates downward.