The Daxin landfill project at Shenyang was the first cooperation between the Welle Group and LAT Water and has proved highly successful. Welle are satisfied with the assistance provided by LAT Water and the plant’s performance since January 2020 and are keen to build a long term relationship with LAT Water to exploit the technology in China.
Pu Yanxin, Director and Deputy General Manager, Welle Environmental Group Ltd
Location
Shenyang, China
Project
Treatment of Raw Leachate
Installed
December 2019
Project Background
In December 2019 LAT Water installed a wastewater treatment plant at the Daxin Landfill (operated by Welle Group) in Shenyang, Northern China. The landfill produces up to 2,000m3/day of leachate which first runs through a reverse osmosis (RO) system. As the installed RO plant cannot fully treat the leachate and produces 120m3/day of highly variable flows of concentrated brine, LAT Water installed two 60m3/day LAT Units working in parallel to enable the treatment of the 120m3/day waste inflow. The units are designed to work 24/7.
Leachate Composition
The raw leachate at Daxin Landfill had an extremely high total dissolved solids (TDS) reading of over 70,00 mg/L, as well as high levels of ammonia and alkalinity – see the table for full details.
Solution & Results
LAT Water installed 2 LAT Units measuring 10x10x25m, with an additional 7x3m of structural support as Shenyang is a medium earthquake risk location. Both Units are also powered by recovering low-pressure steam (waste heat) from the flue gas of an onsite waste incinerator boiler – thus reducing the energy requirements of operation and massively reducing operating costs to less than £2/m3 for input wastewater.
Since installation in 2019, the LAT Units have had over 95% uptime, with only minimal maintenance required despite the varying temperatures and weather conditions throughout the year. The clean product water is also compliant with all local environmental regulations for discharge and the concentrated waste stream is readmitted into the landfill.
The LAT Units were designed to remove a minimum of 70% clean water, but have consistently been achieving in excess of 85% clean water recovery.
IndustriesKey Stats
- Total operating costs: Less than £2/m3 input wastewater
- Uptime: Over 95%
- Clean Water recovery: Over 85%
Water Quality
- Input flowrate: 120m3/day, possible flow variation +/-30%
- Very hard water with a high risk of scaling issues
Climate & Terrain
- Extreme temperature swings (-25°C to +35°C)
- Medium earthquake risk
Maintenance & Monitoring
- The system can be operated and monitored remotely from anywhere in the world and provides ongoing diagnostics, warnings, and alerts.
- The innovative LAT Unit design features a user-friendly, modern touchscreen interface, as well as allowing for easy access should maintenance be required.
- The LAT Unit also has an expected lifetime of over 25 years.
| Paramater | Feed Waste Water | Clean Distillate Water |
|---|---|---|
| TDS (mg/L) | 70,000 | < 50 | pH | 8 | 7 | Sodium (mg/L) | 17,000 | < 80 | Chloride (mg/L) | 34,000 | < 26 |