Serving India, Africa & Middle East since 2003
HomeAboutProductsOur ProcessProjectsGalleryBlogContact
Recovery Island

Chemical Recovery Systems

Complete Chemical Recovery Island — Turnkey Solution by Rajshree India

Get a Free Quote 📞 Talk to an Expert
♻️
QUICK ANSWER

Rajshree Group delivers complete Chemical Recovery Island solutions for kraft pulp mills — integrating black liquor evaporation, recovery boiler, causticising, and lime kiln into a seamless, optimised system.

PROVEN TRACK RECORD

Our 2021 project in Baroda, Gujarat included a multi-effect evaporator and recovery boiler that raised plant efficiency by 30%. Since 2003, Rajshree Group has delivered 22+ pulp and paper projects across three continents — India, Africa and the Middle East — totalling over 2,000 TPD of installed capacity.

Product Overview

The recovery island enables mills to recycle over 95% of cooking chemicals and generate significant power from black liquor combustion, transforming what would be waste into a resource.

Chemical recovery plant with evaporator and recovery boiler by Rajshree Group
Chemical recovery island — evaporator, recovery boiler & causticizing

Key Features

  • MEE evaporation (4–7 effects)
  • Recovery boiler with ESP

Applications

  • Kraft pulp mill integration
  • Chemical recycling and cost reduction
  • Power generation from black liquor
  • Green liquor for causticising
  • Lime recovery and reuse

Our Turnkey Project Process

1
Consultation & Feasibility
We understand your requirements, site conditions, and budget to prepare a detailed feasibility report.
2
Engineering & Design
Complete process design, P&IDs, civil layout, electrical single lines, and equipment specifications.
3
Manufacturing & Supply
In-house and vendor-sourced equipment manufactured, quality-inspected, and dispatched on schedule.
4
Installation & Commissioning
Our engineers supervise erection, electrical, instrumentation, and commission the plant to design parameters.
5
Training & After-Sales Support
Hands-on operator training, performance guarantee trial, and ongoing technical support for the life of the plant.

Technical Specifications

SystemComplete Recovery Island
Chemical Recovery> 95% Na and S
Power Generation30 – 150 MW (plant scale)
White Liquor EA90 – 120 g/L
Lime Mud DR> 92%
NCG HandlingLVHC + HVLC systems
📋

Get a Free Quote

Tell us your capacity requirement and we'll send a detailed technical and commercial proposal within 48 hours.

Request a Quote →

Contact Our Experts

📞+91 87996 27889 📞+1 (219) 256-9887 ✉️sales@rajshreeent.com
📍🏢 Head Office: 60, Swapnil-2 Industrial Park, Kuha, Ahmedabad - 382433, Gujarat, India |
📍 Branch Office: 1913 Gunbarrel Road, Suite 105 Chattanooga, TN 37421, USA |
📍 Branch Office: D7, Varsity Chateau, Uniport Road Aluu, Port Harcourt, Rivers State, Nigeria |

Why Choose Rajshree?

  • 20+ years industry experience
  • 22+ successful projects delivered
  • Serving India, Africa & Middle East
  • Complete turnkey — single point responsibility
  • After-sales support and spare parts
  • Competitive pricing and financing options

How Chemical Recovery Transforms a Kraft Mill's Economics

The chemical recovery island is the financial engine of a kraft pulp mill. Without it, cooking chemical replenishment costs alone would make kraft pulping economically impossible at commercial scale. Rajshree Group designs integrated chemical recovery islands that recover over 95% of cooking chemicals while simultaneously generating steam and electricity from black liquor combustion — turning what was once a costly waste stream into a profit centre.

Our recovery islands comprise four integrated sub-systems: multi-effect black liquor evaporators (concentrating weak liquor from 15% to 65–80% dry solids), the recovery boiler (combusting heavy black liquor to generate steam and smelt), the causticising plant (converting green liquor smelt to white liquor), and the lime kiln (reburning calcium carbonate to regenerate lime). Rajshree engineers all four as a single optimised system with shared utilities and coordinated control logic.

Mills with Rajshree's recovery islands report average steam generation of 3.5–4.5 tonnes of steam per tonne of black liquor fired, with thermal efficiency of 62–68%. This steam surplus is channelled to the paper machine dryer section and process heating, reducing purchased fuel consumption by 60–80% compared to mills without recovery.

♻️ True Circular Chemistry

A properly designed Rajshree recovery island closes the chemical loop so tightly that makeup chemical requirements fall below 5% of total cooking chemical consumption. This dramatically reduces your mill's exposure to sodium hydroxide and sodium sulphide price volatility in the global chemical market.

Frequently Asked Questions

A chemical recovery system reclaims sodium and sulphur chemicals from spent black liquor, allowing them to be reused in the digester. It consists of a multiple-effect evaporator (to concentrate black liquor), a recovery boiler (to burn it), a causticising plant (to convert Na₂CO₃ back to NaOH), and a lime kiln (to regenerate lime). It also generates steam for the mill.
Rajshree supplies recovery systems for black liquor solids production from 30 TPD to 300 TPD, matching the output of the associated pulp mill. System capacity is specified in tonnes of dry solids per day, with recovery boiler steam generation calculated accordingly for the mill's energy balance.
Yes. For soda-process mills (using NaOH only without sulphide), Rajshree supplies a simplified recovery system: multi-effect evaporator, soda recovery furnace (lower temperature than kraft), green liquor clarifier, causticising plant, and lime kiln. The capital cost is lower than a full kraft recovery plant, making it ideal for agro-fibre based mills in India.
Rajshree's recovery boilers generate high-pressure steam (40–60 bar) that drives a back-pressure turbine-generator to produce 2–8 MW of electricity, depending on black liquor solids loading. This power generation significantly reduces the mill's grid power purchase, improving operating economics. Exhaust steam from the turbine is used for process heating.
Rajshree's causticising plants achieve a causticity (conversion efficiency of Na₂CO₃ to NaOH) of 80–85%, within industry norms. The lime availability (unreacted CaO in the mud after causticising) is controlled to below 3% to maximise alkali recovery. Rajshree designs the plant with adequate retention time and temperature control to achieve consistent efficiency.

Countries We Serve

Rajshree Group supplies and installs our Chemical Recovery Systems — and complete pulp & paper mill machinery — for mills across India, Africa and the Middle East, with sea-freight delivery, on-site erection, commissioning and after-sales support in every market we serve.

IndiaNigeriaKenyaGhanaSouth AfricaEgyptTanzaniaUgandaSaudi ArabiaUAE

Explore More Products

🪚
Chipping Plant
View Details →
🧪
CLO2 Plant
View Details →
🍲
Cooking / Digesters
View Details →
💻
DCS Automation
View Details →
🌳
Debarking Plant
View Details →