14/12/2017

Press release: TOAZ completes large-scale repair of ammonia unit no. 5

ToAZ has completed overhaul repair of ammonia unit No. 5 and brought it to design capacity.

The overhaul repair covered nearly all the unit’s assemblies. A large-scale package of repair works on the reformer was completed first: 504 reformer tubes were replaced with oversize ones; also replaced were refractories and convective zone coils. Upgrading also covered the ammonia converter internals and heat exchange equipment of ammonia refrigerating plants. This will allow the unit to operate under higher loads with a reduced natural gas consumption index.

Furthermore, a large scope of work was completed by ToAZ’s in-house repair services, including the repair of the flare facility, which involved the replacement of the flare stack and labyrinth valve. A new feed pump, waste heat boilers, 13 sections of air coolers, and an electrically driven pump were installed; heat insulation on equipment and pipelines was replaced.

The overhaul repair of the syngas compressor, which involved the replacement of the turbine rotor, allowed the compressor output to be additionally increased. The overhaul repair involved replacing internals and protecting the unit’s inside by the diffusion metallisation method. Also, unit No. 5 was fitted with two new acid storage process tanks on new foundations.

During the overhaul repair, Togliattiazot’s specialists inspected the equipment, pipelines and valves, and cleaned the inside of heat exchangers.  They carried out equipment diagnostics for remaining life and technical examination of units and pipelines. A considerable scope of work was also accomplished in the industrial safety area: all the unit’s temperature sensors were inspected and replaced, and new instrumentation was put into service.

Another large-scale stage of repairing unit No. 5 was upgrading the existing water circulation plant by applying current engineering solutions and the latest materials. In particular, the installed variable speed drive motors will allow water circulation cycle fans, depending on weather conditions, to automatically control the temperature of the water coolant of heat exchange equipment. The capacity of the upgraded water circulation cycle of unit No. 5 will be up to 5,000m³ of water per hour.

The overhaul repair also covered the unit’s productions buildings; in particular, the roofing was glazed and repaired, and the administrative building’s heating system was completely replaced.

Viktor Kazachkov, Deputy CEO and Operations Director, Togliattiazot Corporation CJSC: “This is the largest repair in 2017, both in terms of the financing scope and the scope of completed works. We expect a few results: a potential increase in efficiency to 1,750–1,800 tonnes of ammonia per day, in energy efficiency – below 1,100m³ of gas per tonne of product, and extension of run between repairs to two years.”

The overhaul repair of ammonia unit No. 5 was performed as part of ToAZ’s large-scale production capacity upgrading programme. 2015–2017 saw the completion of the repair and upgrading of ammonia units No. 2, 3, 4 and 6, two isothermal ammonia storage facilities, and carbamide units.

Version for print