Acron, Haldor Topsoe complete ammonia unit revamp project 4/27/2021 Acron, one of the world’s largest producers of compound fertilizers based in Russia, and Haldor Topsoe completed the ammonia unit revamp project and successfully passed guarantee test runs to confirm the capacity of 2500 Mtpd of ammonia. Ammonia-4 plant operated by Acron company is one of the largest ammonia units in Europe. It’s a major investment project of Acron’s site in Novgorod city, and it was the first ammonia plant built by Russian specialists without support from foreign workforce. The plant was commissioned in 2016, total investment reached 500M USD. Acron moved beyond and made every effort to increase its capacity and in late 2017, it was decided to revamp the plant and reach 2,500 MTPD.