Waste Treatment and Disposal in Pulp & Paper Industry

BILT Shree Gopal UNIT

Pawan M Paramashetti14CH60R29

Outline

Background

Paper manufacturing process

Generated hazardous waste from industry

-waste water

-solid waste

-gaseous emission

Steps for environmental improvements

Treatment strategies

-Waste water treatment

Conclusion

Ballarpur Industries Limited (BILT) is India’s largest manufacturer of writing and printing

(W&P) paper. Production - 81,442 MT per annum (2009-10)

• The production process consists two main steps: pulping and bleaching.

• Pulping, In this process, wood chips as raw material are treated to remove lignin to

liberate cellulose fibers for papermaking.

• Pulping is the initial stage and the source of the most pollutant of this industry.

• Bleaching is the last step, which aims to whiten and brighten the pulp.

• Whole processes of this industry are very energy and water intensive in terms of the fresh

water utilization.

• 80-90 million kg of toxic pollutants are released every year from this industry.

BACKGROUND

Generated hazardous waste

Waste water :

The waste waters include high concentration of chemicals such as :

Na2CO3, Na2SO3, bisulphites, elemental chlorine or chlorine dioxide, peroxides.

Strong corrosive waste like NaOH, HCl etc.

Adsorbable organic halides (AOX)

The major problems of the wastewater are highly toxicity, corrosivity, high organic content,

dark brown coloration due to dissolved lignin.

Solid waste :

Inorganic waste like lime mud, lime slaker grits, green liquor dregs, boiler and furnace ash,

scrubber sludges, wood processing residuals & wastewater treatment sludges.

Wastewater treatment sludges have a significant concern for the environment because of

including chlorinated compounds.

Gaseous emissions : Particulates

Nitrogen oxides

Volatile organic compounds (VOCs)

Sulphur oxides

• Water conservation

• Waste water management

• Utilization of treated effluent

• Rain water harvesting

• Lime mud management

• Air pollution control measures

• Use of wood waste i.e. Veneer waste, Rolla, etc.

STEPS FOR ENVIRONMENTAL IMPROVEMENTS

Physicochemical treatment (Chemical precipitation)

+

Aerobic treatment (Activated sludge process)

+

Physicochemical treatment (Chemical precipitation/ Air-added floatation)

Physicochemical treatment (Air-added floatation)

+

Aerobic treatment (Fluidized bed biofilm filtration process)

+

Physicochemical treatment (Air-added floatation)

Immersion & cooking facility:

Cleaning & bleaching facility:

Treatment strategies

Annual Chemical consumption

Coagulant (PAC): about 1,800 ton/year

Polymer coagulant (anion): about 14 ton/year

Polymer coagulant (cation): about 34 ton/year

Nutritional supplement: about 855 ton/year

Specification of reactors & primal equipment

• Pre-chemical precipitation tank: φ8m × 4m + φ7.5 × 11m

• Aeration tank: 400 m³

• No1 Post-air-added floatation tank: 3.86m × 6.4m,

• Post-air added clarifier: φ10m

• No.2 Air-added floatation tank: 2.64m(w) × 10.9m(l) × 4.11m(h)

• No.3 Air-added floatation tank: 3.86m(w) × 6.4m(l) × 4.11m(h)

• Fluidized bed biofilm reactor: 3.2 m(w) × 6.6 m(l) × 5.6 m(h) × 2 units

INNOVATIVE PROJECTS

Use of treated effluent in the Jet Condenser in the Chemical House for vacuum generation

and recirculation of used treated effluent back to ETP.

The requirement of treated effluent for Jet Condenser is 4800 m3/day.

Vacuum Pump

Vacuum generation : 625 mm of Hg

Designed - Fresh water requirement : 240 m3/hr.

Actual - Fresh water consumption : 200 m3/hr.

Since, fresh water has been replaced with treated effluent Therefore, Saving in terms of

money : Rs.28.0 lac/annum

By the use of treated effluent, there is a scaling inside the pump and it is being cleaned

mechanically after every four months during the planned shut.

CONCLUSIONS