Meeting environmental standards and objectives can generate an array of benefits: cleaner air or water, improved effluent control, and reduced chemical, energy or other operating costs.
Sandwell offers a full range of waste treatment technologies, including:
- Primary treatment: clarification and settling basin facilities, effluent neutralization, sludge dewatering and sludge transfer
- Secondary treatment: aeration stabilization basins, activated sludge treatment, nutrient addition and sludge conditioning and dewatering
- Tertiary treatment: color removal, dissolved air flotation clarification, chemical treatment systems and sludge handling
- Troubleshooting effluent treatment systems to improve performance and reliability.
As well as providing engineering services on specific projects, we have for many years assisted clients to incorporate environmental programs into their business plans. Such integration is becoming increasingly common as mills adopt Environmental Management Systems (EMS) under the auspices of the ISO 14000 program, or develop Best Management Practices (BMP) plans in compliance with the U.S. EPA Cluster Rule.
Georgia-Pacific Corporation, Brunswick, Georgia
Effluent quality improvements
Sandwell provided detailed engineering and procurement services for liquor and fiber spill collection and recovery systems, spill collection recovery tanks, a new primary clarifier sludge dewatering line, underwater diffuser-type oxygen injection for riverwater enrichment, and a tidal-cycle discharge arrangement for treated effluent to meet applicable environmental requirements for color and BOD reduction in the mill effluent.
Specialty Fine Papers Division, Domtar Inc., Cornwall, Ontario
Turnkey secondary effluent treatment plant
In joint venture with Hydro-Mécanique Construction Inc., this installation included a new spill basin, aeration and equalization basins, two 65m circular secondary clarifiers, two sludge dewatering lines and related systems and buildings.
Georgia-Pacific Corporation,Woodland, ME
Upgrade of mill's waste discharge system
Upgrades to the mill's waste discharge system included a new 50-ton sludge press, two cooling towers to reduce water consumption, and provision for the later addition of an NCG scrubber and refuse hog system.
Weyerhaeuser Canada Ltd., Grande Prairie, Alberta
Installation of an electrostatic precipitator and ash handling system
Installing an electrostatic precipitator and ash handling system (ash conveyors, surge bin and conditioner) on the power boiler enabled the mill to meet new environmental limits on particulate emissions while incinerating more hog than previously. The northern site required draft-free enclosures to protect instrumentation against temperatures as low as -40° C.
Crestbrook Forest Industries Ltd., Cranbrook, British Columbia
Tertiary effluent treatment system
Housed in a large-span steel building, this treatment plant removes color from the effluent stream of the 660 t/d bleached kraft mill. The clarifier system includes a 100 ft diameter low shear dissolved air flotation clarifier, polymer unloading and makedown facilities, and sludge handling system. The first of its kind in Canada, the plant incorporates technology developed by Stone Container Corporation of Atlanta, Georgia.
