VINACHEM

1. Rationale 

To continuously improve environmental management, limit the use of chemicals for treating acid leakages from cast iron pipe systems, and enhance production efficiency while saving electricity, Southern Fertilizer Joint Stock Company has approved investment in upgrading heat exchange materials and cooling methods.

2. Implementation of the Initiative

The team researched materials and cooling methods, prepared cost estimates, and submitted a technical-economic report to the company with the following scope:

• Material Upgrade: Transitioning from cast iron pipe heat exchangers to Alloy C276 plate heat exchangers.

• Cooling Method Upgrade: Transitioning from natural circulation cooling to forced cooling via a Cooling Tower.

Since January 2023, the mixing unit has operated stably. There has been a significant reduction in environmental treatment chemicals, electricity consumption, and the occurrence of replacement parts/maintenance costs. Furthermore, the mixing temperature has been reduced from 80∘C (old technology) to 60∘C (new technology), which significantly reduces H2SO4 vapor emissions into the working environment.

3. Significance and Efficiency of the Research

Following the practical application in the 98% H2SO4 production line at Long Thanh Superphosphate Plant from January 2023 to the present:

• Infrastructure: Reduced the required footprint by approximately 200m2.

• Environmental impact: Eliminated H2SO4 acid leakages and the need for neutralizing chemicals. The circulation water channel system was converted into a surface water drainage system, contributing to environmental protection through the adoption of clean technology.

• Economic impact: The estimated annual cost savings when comparing the old system to the new system is 603,000,000 VND.