Summary: On 9 Nov., the results of post-completion environmental protection (EP) acceptance inspection on NHU Amino Acid's "industry chain extending project for 250,000 t/a methionine" were publicised on the official website of Weifang Binhai Economic and Technological Development Area. The items that were inspected this time include two hydrogen cyanide synthesis devices and a newly built sodium cyanide production device.

On 9 Nov., the results of post-completion environmental protection (EP) acceptance inspection on "industry chain extending project for 250,000 t/a methionine" were publicised on the official website of Weifang Binhai Economic and Technological Development Area. This project was completed by Shandong NHU Amino Acid Co., Ltd. (NHU Amino Acid) and passed EP acceptance inspection. The items that were inspected this time include No.1 hydrogen cyanide synthesis device, No.2 hydrogen cyanide synthesis device, and a newly built sodium cyanide production device.

There are three major production lines in NHU Amino Acid's production plant, which include a 50,000 t/a solid methionine production line, a 100,000 t/a solid methionine production line, and a 150,000 t/a solid methionine production line. The 50,000 t/a solid methionine production line and 100,000 t/a solid methionine production line have been put into operation and passed the self-conducted EP acceptance inspection. As for the third one, the 150,000 t/a solid methionine production line is being constructed, and the purchase of production devices is under way; the overall construction progress is controllable. The construction of this production line is scheduled to be completed in June, 2023, and the subsequent equipment commissioning will be carried out at the same time.

According to the original plan, an ancillary 10,000 t/a No.1 hydrogen cyanide device would be built for the 50,000 t/a solid methionine production line, and an ancillary 30,000 t/a No.2 hydrogen cyanide device would be built for the 100,000 t/a solid methionine production line. But actually, after the construction of those two hydrogen cyanide devices was completed, the hydrogen cyanide from No.2 hydrogen cyanide device alone is sufficient enough to supply 50,000 t/a solid methionine production line and 100,000 t/a solid methionine production line; therefore, the No.1 hydrogen cyanide device became a spare device. In order to implement "industry chain extending project for 250,000 t/a methionine", the company re-activated the spare No.1 hydrogen cyanide device, retrofitted the No.2 hydrogen cyanide device as well as expanded its production capacity, and built a new sodium cyanide device.

Project overview

• Construction site location: Weifang Binhai Economic and Technological Development Area, Shandong Province
• Site area: 2,185.19 square metres
• Total investment: USD1.60 million (RMB11.50 million)
• Investment for environmental protection purposes: USD69,366 (RMB500,000), accounting for 4.35% of the total.
• Type of project: Renovation and expansion
• Construction details:
• No.1 hydrogen cyanide synthesis device has been re-activated. (This device was built in Dec., 2016 and had been laid aside until this project was completed.)
• No.2 hydrogen cyanide synthesis device was technically retrofitted, with capacity increased from 30,000 t/a to 37,200 t/a. (The catalyst used in this device was upgraded and optimised; the ratio of composition in internal structure was adjusted and the specific surface area was enlarged, which makes it easier for active constituents of the catalyst to come into contact with the reactant and enables the production rate of HCN to rise from 3.79 t/h to 4.69 t/h.)
• 25 (sets of) ancillary devices (facilities) were built for the sodium cyanide device, including a first-level absorption tower, a second-level absorption tower, a gas/liquid separator, etc. The sodium cyanide device covers an area of 1,715 square metres. Upon completion of this project, the company now owns 100,000 t/a of production capacity for sodium cyanide solution (30% concentration). The existing two methanol storage tanks and a 32% liquid alkali storage tank are utilised in this project. And a new 50% liquid alkali storage tank and two storage tanks for finished products of sodium cyanide solution were built for this project.
• This project also utilises the existing public and ancillary facilities including drainage, recirculating cooling water system, cooling system, power supply and distribution system, and testing facilities. As for the treatment of waste gas and wastewater, this project utilises the existing ammonia desulphurisation technique, RTO (regenerative thermal oxidiser), No.1 TO (thermal oxidiser) incinerator, and existing wastewater treatment station.
• Product scheme (designed production capacity):
• 100,000 t/a for sodium cyanide 30% solution (for sale)
• 47,200 t/a for 97.5% hydrogen cyanide (intermediate product):
• 17,100 t/a will be used in the production of sodium cyanide;
• 10,000 t/a will be used in the 50,000 t/a methionine production line;
• 20,000 t/a will be used in 100,000 t/a methionine production line;
• 70.93 t/a will be used in the adiponitrile R&D experiment platform project (the construction of which has not yet started)
• Developments in this project: The Environment Impact report of this project was drafted in Nov., 2021 and was approved by the Ecological Environment Bureau of Weifang City on 16 Nov., 2021. The construction of this project commenced in Nov., 2021 and was completed on 8 Dec., 2021.