Project Title Pilot scale studies on efficient depithing of bagasse- … · Availability of baggase...
Transcript of Project Title Pilot scale studies on efficient depithing of bagasse- … · Availability of baggase...
Project Title Pilot scale studies on efficient depithing of
bagasse- a process developed by CPPRI
Project Executed by Central Pulp & Paper Research Institute
(CPPRI), Saharanpur- 247001 (Uttar Pradesh)
Presented by
Dr. A. K. Dixit Sc. E-II & Incharge
Chemical Recovery Division
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR (U.P)(Dept. of Industrial Policy & Promotion, Ministry of Commerce & Industry, Govt. of India)
Project Team
Project Advisor Dr. B. P. Thapliyal
Principal Investigator Dr. A. K. Dixit
Team Member Sh. Kumar Anupam
Sh. Avtar Singh Negi
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
To develop, design and demonstration of pilot scale
depithing equipment for efficient depithing of
bagasse to provide good quality fibre for paper
making and to provide the pith as a source of fuel to
the sugar mills.
Objective
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Quantified Deliverables of the Project
• To develop, design & demonstrate efficient depithing process
developed by CPPRI on pilot scale with improved depithing efficiency
of more than 80% as against 50-55% in conventional processes.
• Reduction in cooking chemicals.
• Improved pulp properties in respect of strength and optical properties.
• Improved quality of black liquor leading to enhanced thermal
efficiency of chemical recovery boiler.
• Diversion of more useful bagasse fiber to paper industry from sugar
mill.
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Paper from Bagasse
• Bagasse is commonly used as a substitute for wood in many tropical
and subtropical countries for the production of pulp, paper and board,
such as India, China, Colombia, Iran, Thailand and Argentina.
• It produces pulp with physical properties that are well suited for
generic printing and writing papers as well as tissue products but it is
also widely used for boxes and newspaper production.
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Availability of baggase
• Major sugarcane growing states are, Uttar Pradesh, Maharashtra,
Tamilnadu and Karnataka.
• Normally 0.30 ton of bagasse (30%) is obtained per ton of cane
crushed in a sugar mill.
• About 50 million tons of bagasse is generated annually in Indian
sugar mills.
• Out of total sugar cane produced in the country
- Only 45% is received by sugar mills
- 45-50% cane is crushed in unorganized sector.
- 8- 10% is utilized as seed for future crop.
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Composition of Bagasse
Bagasse is composed of three principal components namely:
• Rind fibers,
• Fibro vascular bundles
• Ground tissue (parenchyma tissue) or pith.
Whole
Bagasse
6%
32%
62%
Useful Fibre
Pith
Dissolved Matter
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Pith in Bagasse
• Major impediment in utilization of bagasse as an alternative to
wood in papermaking is the inherent carryover of pith to the tune
of 30-35% along with fibre
• Depithing is required prior to pulping of bagasse
• 60% removal of pith is possible with presently employed depithing
methods in industry. Residual pith in the depithed bagasse is above
15%.
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Pith in Bagasse and its Depithing Processes
• Pith is composed mainly of parenchyma cells.
• Pith cannot be converted in to a satisfactory pulp despite its
resemblance to fiber in chemical composition, because of its small
dimensions, non-fibrous physical nature and close association with
dust.
• Efficient depithing of bagasse is essential for good quality
papermaking
• Presently Following depithing Processes are being employed by Paper
mills.
Dry Depithing
Moist Depithing
Wet Depithing
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Pith in Bagasse and its Depithing Processes
COMPOSITION OF DRY/MOIST DEPITHED BAGASSE
COMPOSITION OF WET DEPITHED BAGASSE
COMPOSITION OF CPPRI DEPITHED BAGASSE
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Efficient Depithing Process Developed by CPPRI
• The method involves mechanical treatment of bagasse by passing it
between two disks typically used for short milling operations.
• The treated mass so obtained is subjected to a specially designed
sieving mechanism whereby the useful fibrous portion is
separated from the pith portion in a continuous operation.
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Activities carried out
• CPPRI had installed a depithing system based on its R&D work.
• The system had bottlenecks on:
Frequent jamming of the feeding system
Low capacity of existing screen part
• Looking into the above problems, fabrication of a new feeding system and
screen part was done using indigenous design developed by CPPRI.
• The main goal was to increase the capacity of the existing pilot plant by
fabricating a new whole bagasse feeding system with no jamming
problem.
• Hence, to design and fabricate a new large capacity screen part to
synchronize the increased capacity of feeding and processing system with
the screen part.
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Old Feeding System
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
New Modified Feeding System
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Photograph of new feeding system
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
New versus old feeding system
• New feeding system is equipped with a motor which has increased the
throw put capacity of the depithing plant.
• The bagasse processing capacity of the depithing plant has increased
from previous 3 – 4 tons to present 5 tons.
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Schematic of Depithing Plant Screen
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Old versus New Screen Part Specifications
Parameter Old Screen New Screen
Length of Screen 2.5 m 3.0 m
Mesh Size 01 (Fixed) 03 (Varying)
Polypropylene Brushes Fixed Replaceable
Screen Diameter 365 mm 500 mm
Dia of Shaft 40 mm 40 mm
Material of Construction Mild Steel Mild Steel
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
New Fabricated Screen
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Various Parts of New Fabricated Screen
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Complete Depithing Pilot Plant
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Bagasse and depithed bagasse samples
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Benefits of the process
Pith to Fibre ratio in Bagasse after Depithing
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Impact of depithing on pulp properties
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
Conclusion
• An efficient depithing process has been developed and upscaled to pilot level
which can depith bagasse with 85% depithing efficiency.
• Depithed bagasse has around 6-7%% pith.
• Studies have shown that feeding rate has improved with no jamming problem
withnew feeding system which is perfectly synchronous with new screen part.
• The efficiently depithed bagasse was processed for production of high quality
pulp. Quality of pulp and black liquor were improved.
• Viscosity of black liquor reduces.
• The operation of depithing plant has been demonstrated before various sugar
and paper mills such as Bajaj Hindusthan Sugar Ltd., Yash Paper Mill, Century
Pulp and Paper, and Tamilnadu News Prints & Paper Ltd.
• This pilot plant is available at CPPRI. The mills can come for trial and adoption
of the technology.
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR
CENTRAL PULP AND PAPER RESEARCH INSTITUTE, SAHARANPUR