The invention relates to the technical field of preparation of
acrylic acid by
propylene oxide through a two-
step method, and discloses an optimized and innovative process for preparing
acrylic acid through a two-step
propylene oxide method, which comprises the following steps: firstly, controlling the temperature of a reactor by controlling circulating heat-conducting fused salt in the process, performing multi-point
temperature measurement and APC technology prediction control, and introducing SIS
system linkage; the
temperature control is quicker and more accurate, the temperature of each point of the reactor is prevented from being too high, the catalyst is protected, and the quality of the product
acrylic acid is better. Due to the fact that explosive gas is easily formed after propylene, air and
inert materials are mixed, in order to enable production to be
safer and more stable, a novel APC predictive control technology and a DCS monitoring control scheme are adopted in the process, SIS
system linkage control is combined, the proportion of the
mixed gas is located in a safe area, production is
safer and more reliable, and meanwhile the product conversion rate is the highest. According to the optimization process for preparing the acrylic acid by oxidizing the propylene through the two-
step method, the production is
safer and more reliable, the energy is saved, the efficiency is high, the product quality is higher, the propylene conversion rate and the acrylic acid yield are higher, the expected value of the conversion rate reaches 97%, and the total yield value reaches 88% or above.