Biorefinery implementation for recovery debottlenecking at existing pulp mills- Part II: Techno-economic evaluation

The evaluation and process risk assessment of (a) lignin precipitation from black liquor, and (b) the near-neutral hemicellulose pre-extraction for recovery boiler debottlenecking in an existing pulp mill is presented in Part I of this paper, which was published in the July 2012 issue of TAPPI Journal. In Part II, the economic assessment of the two biorefinery process options is presented and interpreted. A mill process model was developed using WinGEMS software and used for calculating the mass and energy balances. Investment costs, operating costs, and profitability of the two biorefinery options have been calculated using standard cost estimation methods. The results show that the two biorefinery options are profitable for the case study mill and effective at process debottlenecking. The after-tax internal rate of return (IRR) of the lignin precipitation process option was estimated to be 95%, while that of the hemicellulose pre-extraction process option was 28%. Sensitivity analysis showed that the after tax-IRR of the lignin precipitation process remains higher than that of the hemicellulose pre-extraction process option, for all changes in the selected sensitivity parameters. If we consider the after-tax IRR, as well as capital cost, as selection criteria, the results show that for the case study mill, the lignin precipitation process is more promising than the near-neutral hemicellulose pre-extraction process. However, the comparison between the two biorefinery options should include long-term evaluation criteria. The potential of high value-added products that could be produced from lignin in the case of the lignin precipitation process, or from ethanol and acetic acid in the case of the hemicellulose pre-extraction process, should also be considered in the selection of the most promising process option.

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Analysis of economically viable lignin-based biorefinery strategies implemented within a kraft pulp mill

TAPPI Journal ◽

10.32964/tj16.3.157 ◽

2017 ◽

Vol 16 (03) ◽

pp. 157-169 ◽

Cited By ~ 4

Author(s):

Cedric Diffo Teguia ◽

Rod Albers ◽

Paul Stuart

Keyword(s):

Black Liquor ◽

Pulp Mill ◽

Extraction Process ◽

Government Support ◽

Product Portfolio ◽

Phenolic Resins ◽

Lignin Extraction ◽

Near Term ◽

Process Strategy

Many pulp and paper companies are considering implementing a lignin-based biorefinery to diversify their core business to new products and improve their longer-term competitiveness. The best strategy to achieve might not be obvious, considering the lignin extraction process and derivatives to be implemented over the longer term that meet market and business objectives, and provide competitive advantage. In this article, various lignin biorefinery strategies were considered in a case study involving lignin precipitation processes integrated within an existing kraft mill, and solvent pulping processes that would be implemented in parallel to the existing mill processes using additional hardwood. The analysis aimed to identify the conditions under which various strategies would represent suitable investments. Operating constraints in the case study mill limited lignin extraction to 85 metric tons/day from 15% of the mill’s black liquor, whereas 260 metric tons/day lignin could be extracted by solvent pulping 1500 metric tons/day of hardwood. The preferred strategies identified by the study were lignin precipitation to phenolic resins production, and solvent pulping to carbon fiber production. The first product-process strategy requires lower investment, provides high returns (internal rate of return [IRR] of 39% to 43%), and is more easily implemented in the near term. Solvent pulping resulted in reasonable profitability (IRR of 18% to 25%), with higher production volumes and a diversified product portfolio, and was considered more suitable as a longer-term strategy. Business model robustness and long-term competitiveness can be better assured by combining both strategies. It was shown that 1) government support to offset capital cost, and 2) high derivatives market prices positively influence lignin valorization strategies, which are sensitive to technology and market maturity.

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An empirical model of four processes for sharing organisational knowledge

Online Information Review ◽

10.1108/oir-03-2013-0059 ◽

2014 ◽

Vol 38 (2) ◽

pp. 305-320 ◽

Cited By ~ 7

Author(s):

August Tsai

Keyword(s):

Business Process ◽

Empirical Model ◽

Process Model ◽

Value Added ◽

Technology Infrastructure ◽

Knowledge Application ◽

Content Type ◽

Proposed Model ◽

Organisational Knowledge

Purpose – This study aims to introduce an empirical model which incorporates newsgroups, knowledge forums, knowledge assets and knowledge application processes to share organisational knowledge. Therefore it seeks to illustrate an application for integrating knowledge management (KM) into the business process. Design/methodology/approach – The Taiwanese contingent of an international certification body – also a council member of the International Organisation for Standardisation (ISO) – was selected for a case study. A hybrid technology infrastructure was designed and employed to implement the proposed model. Based on knowledge value added validation, the proposed KM model provides a set of new operating systems for sharing knowledge within an organisation. Findings – Although many theories regarding implementation of KM in organisations have been proposed and studied, an application model for practical integration of various modern principles to share organisational knowledge is strategically important. Therefore a model that integrates principal KM applications into the business process, and the measurement of the resulting benefits, has been developed. Originality/value – Knowledge is a valuable asset for an individual in today's economy; nevertheless the acquisition of such an asset relies heavily on knowledge sharing within an organisation. The author has proposed an exclusive hybrid platform with an empirical process model to address innovative approaches and practical values of KM within an organisation.

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The trend of software cost estimation in Ethiopia Case study : Addis Ababa

International Journal Of Engineering And Computer Science ◽

10.18535/ijecs/v8i12.4413 ◽

2019 ◽

Vol 8 (12) ◽

pp. 24901-24906

Author(s):

Asebe Teka Nega

Keyword(s):

Cost Estimation ◽

Addis Ababa ◽

Estimation Methods ◽

Software Cost Estimation ◽

Software Cost ◽

Implementation Phase ◽

Software Company

For a different item, you can purchase it. There are different costs to purchase that you can analysis the benefit and loses, even if on the software it has different approaches to analysis their wages, the developer company can get their analysis by the different methods. There are a lot of software cost estimation methods are appearing in different years but still, those methods have their own drawback on making a correct effort and scheduling estimation, here in the paper Today there are different software cost estimation methods that the software company uses from the requirement to implementation phase. Corrected cost estimation supports us to complete the project on planned times and budgets. This paper is mainly presenting the current situations of cost estimation on software placed in Addis Abebas different software compony

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Assessing of Losses and Dilution Impact on the Cost Chain: Case Study of Gold Ore Deposits

Sustainability ◽

10.3390/su13073830 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3830

Author(s):

Mikhail Marinin ◽

Oksana Marinina ◽

Radosław Wolniak

Keyword(s):

Cost Estimation ◽

Cost Savings ◽

Efficient Solutions ◽

Quality Parameters ◽

Ore Deposits ◽

Production Costs ◽

Estimation Methods ◽

Production Cycle ◽

Production Chain

The conditions of declining gold grade in the ore, increasing depth of excavation, and de-creasing unallocated stock of deposits make it necessary to develop efficient solutions for the mine-to-mill process, which have to be adapted to each specific mining plant and will optimizes production costs. Current research focuses on a case study that demonstrates how indicators of mining losses and dilution influence the variation of costs chain in the production cycle. The article examines the topical issue of determining the effects at the mine-to-mill stages due to changes in losses and dilution. The author’s approach to the formation of a mine-to-mill cost chain is proposed by integrating several cost estimation methods into the general cost estimation methodology. The estimation methodology is a compilation of factor analysis and cost engineering methods that take into account the change in costs due to the variation of losses and dilution. It was proven that with variations in losses and dilution, cost savings arise due to changes in the volume of work on ore averaging, ore transportation, and beneficiation. For the case of the Kuranakh ore field, there are no effects at the mining stage. The use of internal reserves by means of managing ore quality parameters allows reducing the costs per ton of processed rock mass along the entire production chain.

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Wastewater to Ecological dyeing process and bioactive compounds resources: case study of Dittrichia graveolens hydrodistillation aqueous residue

10.21203/rs.3.rs-41640/v1 ◽

2020 ◽

Author(s):

Nawres Gharred ◽

Noureddine Baaka ◽

Nadir Bettache ◽

Assia Hamdi ◽

Amal Dbeibia ◽

...

Keyword(s):

High Performance ◽

Biological Activities ◽

Value Added ◽

Extraction Process ◽

Phytochemical Study ◽

Dyeing Process ◽

Aqueous Residue ◽

Real Risk ◽

Biological Potential

Abstract The release of aqueous residues generated by the extraction process of essential oils presents a real risk of environmental pollution. This work aims to reduce this risk and produce value-added materials. The aqueous residue of Dittrichia graveolens (D. graveolens) hydrodistillation has been reused in two valorization ways: 1/ in the ecological dyeing. 2/ in biological field. First, a phytochemical study of the aqueous residue was carried out by determining the ployphenols and flavonoids content and high performance liquid chromatography (HPLC) analysis. Second, the eco-dyeing process with the aqueous residue was performed on the polyamide fabric, the process was optimized by the surface response methodology using Minitab software and was evaluated by the fastness tests for the optimal conditions. Third, the aqueous residue was assessed for its biological activities. Promising coloring power and biological potential of the aqueous residue showed that this last could be an important source for developing environmentally friendly natural dyes and bioactive products.

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Synthesis of A Sustainable Sago-Based Value Chain via Fuzzy Optimisation Approach

MATEC Web of Conferences ◽

10.1051/matecconf/201815201004 ◽

2018 ◽

Vol 152 ◽

pp. 01004 ◽

Cited By ~ 1

Author(s):

Jeffrey Hong Seng Chong ◽

Yoke Kin Wan ◽

Viknesh Andiappan

Keyword(s):

Waste Management ◽

Value Chain ◽

Value Added ◽

Extraction Process ◽

Sago Starch ◽

Industrial Case Study ◽

Industrial Practice ◽

Sago Bark ◽

Value Added Products

Sago starch is one of the staple foods for human, especially in Asia’s Region. It can be produced via sago starch extraction process (SSEP). During the SSEP, several types of sago wastes are generated such as sago fiber (SF), sago bark (SB) and sago wastewater (SW). With the increase in production of existing factories and sago mills, the sago industrial practice in waste disposal management is gaining more attention, thus implementation of effective waste management is vital. One of the promising ways to have effective waste management is to create value out of the sago wastes. In a recent study, sago-based refinery, which is a facility to convert sago wastes into value-added products (e.g., bio-ethanol and energy) was found feasible. However, the conversion of other value added products from sago wastes while considering the environmental impact has not been considered in sago value chain. Therefore, an optimum sago value chain, which involved conversion activities of sago wastes into value-added products, is aimed to be synthesised in this work. The optimum sago value chain will be evaluated based on profit and carbon emissions using fuzzy-based optimisation approach via a commercial optimisation software, Lingo 16.0. To illustrate the the developed approach, an industrial case study has been solved in this work.

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Managing total reduced sulfur emissions at a Canadian kraft pulp mill

TAPPI Journal ◽

10.32964/tj15.4.265 ◽

2016 ◽

Vol 15 (4) ◽

pp. 265-272 ◽

Cited By ~ 1

Author(s):

ROHAN BANDEKAR ◽

JIM FREDERICK ◽

JAROSLAV STAVIK

Keyword(s):

Direct Contact ◽

Black Liquor ◽

Pulp Mill ◽

Packed Bed ◽

Average Value ◽

Emission Limit ◽

Total Reduced Sulfur ◽

Reduced Sulfur ◽

Air Ingress ◽

Solids Content

This study addresses the challenges a dissolving-grade pulp mill in Canada faced in 2014 in meeting its total reduced sulfur (TRS) gas emission limit. These emissions from the recovery boiler exit are controlled by passing the boiler exit gas through a TRS scrubber system. The mill employs a cyclonic direct contact evaporator to concentrate black liquor to firing solids content. The off-gases from the direct contact evaporator flow to the effluent gas control system that consists of a venturi scrubber, a packed bed scrubber, and a heat recovery unit. Emissions of TRS greater than the regulated limit of 15 ppm were observed for a 4-month period in 2014. The level of emissions measured during this period was significantly higher than about 12 ppm, the expected average value based on historic experience. The problem persisted from mid-June 2014 until the annual mill shutdown in October 2014. The main TRS components detected and the performance of the Teller scrubber in capturing them are examined. Other potential causes for these emissions are identified, including mechanical problems such as broken packing in the TRS packed bed scrubber, broken baffle plates in the scrubber, and cyclone evaporator leaks causing air ingress. Repairs were carried out during the mill shutdown, which eliminated the TRS emissions problem.

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Commissioning brownstock washing controls for an evaporator limited mill

TAPPI Journal ◽

10.32964/tj15.7.459 ◽

2016 ◽

Vol 15 (7) ◽

pp. 459-464

Author(s):

RICARDO SANTOS ◽

PETER HART

Keyword(s):

Control System ◽

Negative Impact ◽

Black Liquor ◽

Pulp Mill ◽

Control Program ◽

Separation Point ◽

Water Control ◽

Oxygen Delignification ◽

Percentage Points

An automated shower water control system has been implemented to reduce the volume and variability of weak black liquor being sent from the pulp mill to the evaporators. The washing controls attempt to balance the need for consistent and low soda carryover to the bleach plant with consistently high weak black liquor solids being sent to the evaporators. The washer controls were implemented on two bleachable grade hardwood lines (one with oxygen delignification, one without oxygen delignification) and one pine line. Implementation of the control program resulted in an increase in black liquor solids of 0.6 percentage points for the hardwood lines. Significant foam reduction was realized on the pine line since the pine black liquor solids were able to be consistently maintained just below the soap separation point. Low black liquor solids excursions to the evaporators were eliminated. Bleach plant carryover was stabilized and no negative impact on chemical consumption was noticed when controlling weak black liquor solids to recovery.

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