**5.1 'Bio-scouring', the new way**

 The aforementioned disadvantages of scouring with sodium hydroxide has motivated the textile industry to introduce more enhanced biological agents, which would be as effective in removing non-cellulose substances but would not have any damaging effects on cotton and would be less energy and water consuming. As we all know the outer protective coating of the cotton fibre is made up of pectin. The primary aim of any scouring process is to break this outer pectin layer. Once this is broken the cellulose polymers present inside the cotton fibrils are exposed. These have high affinity for water due to abundance of hydroxyl group, thus making the cotton fibre hydrophilic. If there is a way to break this pectin through some other route then the desired scouring effect can be achieved easily.

Pectins, chemically are high molecular weight, negatively charged, acidic, complex branched heteropolysaccharides primarily containing an alpha- (1,4) polygalacturonic acid backbone which can be randomly acetylated and methylated. Contrary to the proteins, lipids and nucleic acids, pectic substances do not have a defined molecular weight. Three different kinds of pectins have been isolated from cotton:

1. Homogalacturonans: These are composed of simple alpha-(1,4) polygalacturonic acid backbone. Some modifications of Homogalacturonans backbone with beta-D- Xylose branching at C3, or apiofuranose substitutions in the backbone with beta-D-Apiosyl- (1,3')-beta-D-Apiose branching are also found. A typical structure of homogalacturonans can be represented as follows:

Pre-treatment of Textiles Prior to Dyeing 227

To break this outer pectin layer of cotton fibre, Pectinase enzymes can be used. In general it can be said that the pectinases or pectinolytic enzymes catalyze the random hydrolysis 1, 4 alpha-D-galactosiduronic linkages in pectin substances. These enzymes are further classified based on the specificity of their reaction sites. Four main types of enzymes are used to break down pectin substances namely protopectinases, pectin esterases, polygalacturonases and pectin lyases. All these three different types have different roles to play in pectin

**Protopectinases:** These catalyze the solubilisation of insoluble protopectin and give rise to

They are classified in to two types based on their reaction mechanism. A-type protopectinases and B- type protopectinases. A-type reacts with the inner site i.e. polygalacturonic acid of protopectin whereas B- type react on the outer side i.e. on the polysaccharides chain that may connect the polygalacturonic acid chain and cell wall constituents. A-types have molecular weight of about 30 KDa. B- types have molecular

Protopectinases Protopectin (Insoluble) + H2O Pectin ( Soluble)

**Pectin Esterases:** These liberate pectin and methanol by de-esterifying the methyl ester

O O

Their activity is highest on 65- 75% methylated pectin, since the enzyme is thought to act on methoxy group adjacent to free carboxyl group. Its action has very little effect on the molecular weight of the pectin. These are highly specific enzymes. Some of them attack only the reducing end while the others attack the non- reducing end. Molecular weights vary in the range of 35- 50 KDa. They are active in the pH range of 4-8. Optimal temperature range

O O

**Polygalacturonases:** These enzymes directly reduce the molecular weight of the pectins. They catalyze the hydrolytic cleavage with the introduction of water across the oxygen

degradation.

highly polymerized soluble pectin.

weight of about 45 KDa.

linkages of pectin backbone.

for maximum activity is 40- 500C.

bridge.

2. Rhamnogalacturonans I. - This contains alternating alpha-(1-4) galacturonosyl and alpha-(1-2) rhamnosyl residues, with primarily oligo alpha-(1-3) arabinose and oligo beta-(1-4) galactose branching. Atypical structure of it can be represented as follows:

3. Rhamnogalacturonans II. - It is composed of simple alpha-(1,4) polygalacturonic acid backbone with complex branching with composed of up to 11 different monosaccharide types. A typical structure of it can be represented as follows.

2. Rhamnogalacturonans I. - This contains alternating alpha-(1-4) galacturonosyl and alpha-(1-2) rhamnosyl residues, with primarily oligo alpha-(1-3) arabinose and oligo beta-(1-4) galactose branching. Atypical structure of it can be represented as follows:

3. Rhamnogalacturonans II. - It is composed of simple alpha-(1,4) polygalacturonic acid backbone with complex branching with composed of up to 11 different monosaccharide

types. A typical structure of it can be represented as follows.

To break this outer pectin layer of cotton fibre, Pectinase enzymes can be used. In general it can be said that the pectinases or pectinolytic enzymes catalyze the random hydrolysis 1, 4 alpha-D-galactosiduronic linkages in pectin substances. These enzymes are further classified based on the specificity of their reaction sites. Four main types of enzymes are used to break down pectin substances namely protopectinases, pectin esterases, polygalacturonases and pectin lyases. All these three different types have different roles to play in pectin degradation.

**Protopectinases:** These catalyze the solubilisation of insoluble protopectin and give rise to highly polymerized soluble pectin.

$$\text{Protonection (Insolvable)} + \text{H}\_2\text{O} \xrightarrow{\text{Protonpecieses}} \text{Pectin (Soluble)}$$

They are classified in to two types based on their reaction mechanism. A-type protopectinases and B- type protopectinases. A-type reacts with the inner site i.e. polygalacturonic acid of protopectin whereas B- type react on the outer side i.e. on the polysaccharides chain that may connect the polygalacturonic acid chain and cell wall constituents. A-types have molecular weight of about 30 KDa. B- types have molecular weight of about 45 KDa.

**Pectin Esterases:** These liberate pectin and methanol by de-esterifying the methyl ester linkages of pectin backbone.

Their activity is highest on 65- 75% methylated pectin, since the enzyme is thought to act on methoxy group adjacent to free carboxyl group. Its action has very little effect on the molecular weight of the pectin. These are highly specific enzymes. Some of them attack only the reducing end while the others attack the non- reducing end. Molecular weights vary in the range of 35- 50 KDa. They are active in the pH range of 4-8. Optimal temperature range for maximum activity is 40- 500C.

**Polygalacturonases:** These enzymes directly reduce the molecular weight of the pectins. They catalyze the hydrolytic cleavage with the introduction of water across the oxygen bridge.

Pre-treatment of Textiles Prior to Dyeing 229

From the above literature survey, it is very clear that the cotton can be bio- scoured using Pectinases enzyme. As we have seen there is a large pool of sources from which Pectinases enzyme can be obtained and also a huge number of combinations possible depending on the type of pectin degradation required. At Rossari Biotech Ltd, R & D department have developed a bio scouring enzyme named 'Scourenz ABE Liquid', that is successful in producing the desired scouring effects on cotton and its blends. It's a complex mixture of Protopectinases and Polygalacturonases that completes the bio scouring process in 30- 45mins and gives a fabric with absorbency within 4-5 seconds. Lower treatment temperature of 55- 60°C and milder acidic conditions with a pH requirement of 5- 5.5 are the advantages that have proven to be a boon to our customers that are currently using this enzymes.

Saves Wat er Saves Time

Load the material

Bio scouring at 550C for 30 min

Raise temperature of same bath to 900C and hold for 10 min.

Drain

Start Dyeing The actual bio-scouring process takes place at 550C. In this step the pectins are decomposed and emulsified. After bio-scouring, raising the temperature of the same bath to 900C helps in melting of waxes and oils. These released waxes are emulsified at high temperature and the bath is drained. This removes the entire impurities from the bath and the cotton substrate is

The enzymatic process of bio- scouring on bulk scale involves following stages:

Transfer of enzyme molecules from aqueous phase to fibre surface

Adsorption of enzyme molecule on to the substrate surface

The process route that has to be used for carrying out bio scouring operation is:

Saves Energy Economic

**5.2 Rossari's Bio- scouring enzyme – 'Scourenz ABE Liquid '**

Environment Friendl y

ready for dyeing.

These are the most commonly used enzymes in the market. They are classified further as endo- galacturonases and exo- galacturonases. Endo types are found extensively in nature whereas exo-types occur less frequently. Polygalacturonases obtained from different sources vary widely with respect to their physiochemical and biological properties as well as their mode of action.

**Pectin Lyases:** They also contribute to the depolymerisation of pectin. These catalyse the trans- eliminative cleavage of the galacturonic acid polymer. The lyases break down the glycosidic linkages at C-4 and simultaneously eliminate H from C-5 position, producing an unsaturated product.

In a much simplified way, the action of the above mentioned Pectinase enzymes can be summarized pictorially in the figure given below:

Friendl y

228 Textile Dyeing

These are the most commonly used enzymes in the market. They are classified further as endo- galacturonases and exo- galacturonases. Endo types are found extensively in nature whereas exo-types occur less frequently. Polygalacturonases obtained from different sources vary widely with respect to their physiochemical and biological properties as well as their

O O

O O

O

O

**Pectin Lyases:** They also contribute to the depolymerisation of pectin. These catalyse the trans- eliminative cleavage of the galacturonic acid polymer. The lyases break down the glycosidic linkages at C-4 and simultaneously eliminate H from C-5 position, producing an

In a much simplified way, the action of the above mentioned Pectinase enzymes can be

mode of action.

unsaturated product.

O

O

summarized pictorially in the figure given below:


**1. Introduction**

Mesenchymal stem cells are stromal cells that can be differentiated into bone, cartilage, and fat cells [1]. These stem cells can be found in various tissues, including bone marrow and fat [2]. The ability to form cellular aggregations has been utilized in a three-dimensional model [3]. These three-dimensional structures using stem cells were reported to maintain cell survival and function and were applied for tissue engineering purposes [4]. Spheroid culture has recently been of interest, especially for regeneration purposes [5]. In detail, spheroid culture produces an increased secretion of cytokines, such as vascular endothelial growth factor and granulocyte

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

colony stimulating factor, when compared with that from two-dimensional cultures [6]. The aim of this review was to describe the two- and three-dimensional cultures, and the morphological comparison will be performed between two-dimensional culture and spheroid culture.

**Figure 2** shows morphology of the stem cells cultured in adipogenic media (STEMPRO® Adipogenesis Differentiation Kit, Gibco, Grand Island, NY, USA). The cells were supplied with adipogenic induction medium and adipogenic maintenance medium alternately. The cells' morphology was viewed under an inverted microscope (Leica DM IRM). **Figure 3** shows morphology of the stem cells cultured in adipogenic media for a longer period of

Morphological Comparison of Stem Cells Using Two-Dimensional Culture and Spheroid Culture

http://dx.doi.org/10.5772/intechopen.81471

141

**Figure 2.** Morphology of the stem cells cultured in adipogenic media on Day 5. (a) The morphology of the cells at low

**Figure 3.** Morphology of the stem cells cultured in adipogenic media on Day 13. (a) The morphology of the cells at low magnification (original magnification 100×), (b) higher magnification shows that cells have a ghost-like feature (original

magnification 100×) and (c) more distinct feature of abiogenesis is shown (original magnification 200×).

magnification (original magnification 100×) and (b) higher magnification (original magnification 200×).

13 days.


*2.11. Statistical Analysis*

A two-way analysis of variance (ANOVA) was performed with SPSS software version 17.0 for Windows to analyze the data and presented as a treatment mean ± SE (*n* = 4). The least significant difference (LSD) was calculated for the significant data at *p* < 0.05. The data bars with the same letter were not significantly different by the LSD test at *p* < 0.05. The principal component analysis (PCA) and Pearson correlation analyses (*p* < 0.05, *p* < 0.01 and *p* < 0.001) were carried out using OriginPro software. To create biplots, the first two components (PC1 and PC2) showing the maximum variance in the datasets were considered.


**6. Conclusion**

*Concepts, Applications and Emerging Opportunities in Industrial Engineering*

In this step, the results are sustained in the process or system if the considerable improvement is observed. The whole process is reevaluated using lifecycle assessment (LCA) and value stream mapping (VSM) techniques to judge the level of emissions and waste reduction. Also, various observations, control charts, and data collection techniques are used to reassess the sigma level, Cpk, electricity, water, material consumption, etc. If the sustained results are not found, then an action plan is also initiated to select an appropriate solution. Through the execution of LGSS, the firm can gain improved sustainability, reputation, and global market

LGSS is in the evolution phase and most of the firms oppose adopting such type of strategy due to the change in routine work method into their operation. However, the presented framework will help the organization for improving sustainable performance through overcoming the barriers and constraints which come in front

After the integration of these strategies, one can correlate the different functionality of these modern techniques. It has found that top management support, a culture of the organization, and team work are the crucial success factors for the execution of such a program [4, 8]. In the same way, there are certain challenges to adopt these strategies because of improper guidance and roadmap to achieve set objectives of the firm [36]. There is a need to find out such types of obstacles during the execution of the improvement program within a given time frame to take a

The LGSS tools and techniques overcome the barriers and at the same type advanced statistical tools help to find out the root cause of the problems and also to find out the solution for such type of problems. Currently, most of the organizations want to implement such types of manufacturing philosophies into their operation to enhance productivity, on-time delivery, improved quality, and reduced cost. In the LGSS framework, the Define-Measure-Analyze-Improve-Control (DMAIC) approach helps to overcome the barriers of the Lean-Green approach to delivering

"The limitation of this work is that the presented framework has not tested statistically; in the future, the research will be based on an empirical study to be carried out in different industrial sectors." To validate the proposed plan, an empirical study taking a survey of manufacturing industries in which those practices are going on into their operation has need to be taken and then it should be statistically

In execution steps as shown in **Figure 3**, problem identification should be based on LGSS practices. Meanwhile, every problem that faces in the industry must be identified and solved by LGSS tools and techniques. Moving toward step 2, there should be an assessment of the current state of the problem to know the issues in the process. After that, the main drivers of the issues are associated with the inefficiency. Hence, the root causes using the fishbone diagram, 5 Why, DOE, etc. should be found out to deliver productivity to the system. After finding the root

*3.1.5 Step 5: sustain the best results*

**4. Results and discussion**

of the execution.

competitive advantage.

the sustainable results.

**5. Proposed plan for validation**

validated using SPSS-AMOS software.

through the delivery of eco-friendly products.

**90**

The LGSS approach reduces the negative environmental effect and improves operational, social, and financial performance. The integrated LGSS framework presented is based on theoretical elements such as tools and techniques, barriers, and enablers. Top management support and teamwork have a significant effect on execution of LGSS. The proposed framework provides a way of starting from project identification to finding a solution to the problem of implementation in a system/process. The stepwise framework of LGSS provides help to the operation manager to execute this sustainable approach irrespective of the size, culture, and type of industry. Providing this integrated approach, definitely, the organization can enhance its operational productivity keeping in mind socio-economic needs and global competitive pressure that force the organization to implement such type of approach.


**Abstract**

In addition to the accelerated development of standard and novel types of rechargeable batteries, for electricity storage purposes, more and more attention has recently been paid to supercapacitors as a qualitatively new type of capacitor. A large number of teams and laboratories around the world are working on the development of supercapacitors, while their ever-improving performances enable wider use. The major challenges are to improve the parameters of supercapacitors, primarily energy density and operating voltage, as well as the miniaturization, optimization, energy efficiency, economy, and environmental acceptance. This chapter provides an overview of new techniques and technologies of supercapacitors that are changing the present and future of electricity storage, with special emphasis on self-powering sensor and transmitter systems. The latest achievements in the production, modeling, and characterization of supercapacitor elements (electrode materials, electrolytes, and supporting elements) whose parameters are optimized for long-term self-supply of low power consumers (low voltage, high energy density, and low leakage current, etc.) are considered.

**Keywords:** supercapacitors, innovation, energy storage, application

### **1. Introduction**

For decades, science has been intensively researching electrochemical systems that exhibit extremely high capacitance values (in the order of hundreds of Fg1 ), which were previously unattainable. The early researches have shown the unsuspected possibilities of supercapacitors and traced a new direction for the development of electrical energy storage systems [1]. In recent times, with the development of new materials and technologies, very large developed surfaces and very small inter-electrode distances have been achieved. In many materials, enormous pseudocapacitance is also expressed, which achieves extremely large capacitances (several orders of magnitude larger than standard capacitors), so such systems are called supercapacitors (supercapacitors or, more rarely, ultracapacitors) [2].

There are two types of supercapacitors, depending on the energy storage mechanism: electric double-layer capacitors and pseudocapacitors [3]. In the first case, it is an electrostatic principle, and in the second one, the charge storage is caused by fast redox reactions [4]. Some electrode materials have both one and the other mechanism, thus so-called hybrid capacitors are formed on their basis.

High needs for powering isolated systems (sensor networks and IoT), covering peaks of electricity consumption, filtration, and new more efficient topologies in power electronics require further development and improvement of supercapacitor properties. More on this topic is given in Section 2 of this chapter.

New technologies and new materials in this area are presented in Section 3 of this chapter. Fabrication, modeling, and characterization are presented in Section 4.

Supercapacitors are widely used due to their high-power density, that is, fast charge and discharge, and a huge number of charge/discharge cycles [5]. Increasing the performance of supercapacitors opens up new fields of application and attention will be paid to this in Section 5. The growth of the industry in this area causes a drop in prices, which will be discussed in Section 6.

### **2. Need for supercapacitors**

Since the energy harvesting from renewable energy sources is highly actual today, the studies are also focused on the diverse methods for storing this energy in the form of electricity. Supercapacitors are one of the most efficient energy storage devices. As they have many advantages, supercapacitors are continuously being used in devices and systems that are eager for a high-power supply, opposite to the batteries. Recently actual, supercapacitors' applications are driven by their high performance and market potential, placing them in many fields of interest, such as industrial control, power, transportation, consumer electronic products, national defense, communications, medical equipment, electric and hybrid vehicles [6–8].

Nowadays, with the rapid development of intelligent electronic devices, have placed flexible energy storage devices in the focus of researchers. The industry requires energy storage that are flexible and optimized but endowed with high electrochemical properties [8–10]. The advantages of the supercapacitors, such as charge-discharge cycle life, size and weight, and environmentally oriented, suiting them for various applications. Supercapacitors are being used more and more as applications require storing and releasing high amounts of energy in short periods. Current industry applications include the automotive industry, hybrid transportation systems around the world, grid stabilization, utility vehicles, and rail-system power models [11].

The storing of energy is one of the main applications of supercapacitors. Following their outstanding power characteristics, supercapacitors are vital for the energy sector and their stationary applications. Additionally, the low maintenance requirements, as well as the extreme conditions that supercapacitors are able to withstand, make them suitable for renewable energy-related applications [12, 13]. Furthermore, the supercapacitors provide substantial benefits to railway electricity systems and the aerospace industry, since these sectors are trying to achieve a more electric power supply [13, 14]. Furthermore, many systems in the industrial sector are using supercapacitors, including small vehicles, such as forklifts, shovel trucks, agricultural machinery, excavators, mining shovels, harbor cranes, and industrial lasers. Consumer electronics are relying on supercapacitors, especially in real-time clock or memory backup, power failure backup, storage applications in which supercapacitors are used instead of batteries, and high load assistance to the primary electrical energy storage systems [13].

### **3. New technologies and materials for supercapacitors**

Supercapacitors are increasingly used for energy storage due to their large number of charge and discharge cycles, high power density, minimal maintenance, long life

span, and environmental friendliness [15]. The only disadvantage over batteries, the lower energy density, is decreasing more and more thanks to the intensive development of new technologies and new materials. Hybrid electrodes that combine doublelayer (electrostatic) capacitance and pseudo (redox) capacitance are increasingly being used [16].

The latest nanotechnologies have given rise to nanomaterials, such as 2D graphene, 1D CNT, and 0D fullerene [17]. There is a high trend in the research of carbon-based electrode materials (CNT, graphene, fullerene and their composites with metal oxides, etc.), copper sulfide and other metals, and metal oxides, all in combination with appropriate electrolytes.

For years, the authors of this chapter have researched the possibility of using natural copper minerals, primarily chalcosine [18] and coveline [19].

The latest research in the field of perovskite oxide applications for supercapacitor electrode materials deserves special attention. Perovskite oxides based on lanthanum, strontium, and cerium, etc. are being researched [20].

The researches with polymer materials are of great interest as well, which, in addition to high power density, also has an acceptable energy density (**Figure 1**). Conductive polymers are materials that contain a conjugated double bond, which places them in the group of materials that exhibit good electrical conductivity. Apart from showing electrical conductivity, these materials are characterized by redox reactions that take place when the electrode is polarized in a certain potential range. As a consequence of the redox reaction, constant currents are recorded in a wide range of potentials, which indicates the continuous development of the redox reaction in the

**Figure 1.** *Ragone plot shows the energy vs. power density comparison of supercapacitors with the other energy storage devices [21].*

**Figure 2.** *Comparison of various materials according to their specific parameter for supercapacitor applications [21].*

investigated potential range. The resulting response is similar to the electrochemical response of charging/discharging the double layer and therefore these reactions are called pseudocapacitive reactions. This property enables the application of these materials in supercapacitors. In order to further improve the properties of conducting polymers, attempts are being made to increase their electrical conductivity and porosity [21].

In **Figure 2** a comparative review of current supercapacitor electrode materials has been provided. Carbon materials have a specific capacitance of up to 300 F/g, while polymer and metal oxide materials can have over 1000 F/g. Composites of two or more of the above materials can have a very high specific capacitance of over 2000 F/g. Recently, the predominant approach is the development of binary or ternary nanocomposites of different capacitive materials to determine and optimize the structures and physical and mechanical properties of the electrode materials, in order to achieve improved supercapacitor performance. However, the properties of composite electrodes, in addition to the individual active components, also depend on the morphology and characteristics of the interphase [21].

Special, often complex technologies are developed for the production of superior electrode material. In **Figure 3** one of them is shown. A schematic diagram of the entire process of MnNi2O4@MnNi2S4 electrode materials is presented. Ni2+ and Mn2+ form Mn-Ni precursors in the reactor and are then calcined at high temperature to produce oxides. Then, under the influence of sodium sulphide, ion exchange is carried out at the appropriate temperature, i.e. oxygen is replaced by sulphur, which is less electronegative. A core-shell structure is formed without changing the morphology of the oxide. Metal ions react with KOH electrolyte in the Faraday redox reaction [22].

*Supercapacitors: The Innovation of Energy Storage DOI: http://dx.doi.org/10.5772/intechopen.106705*

**Figure 3.** *The schematic diagram of the construction process for MnNi2O4@MnNi2S4 electrode [22].*


**8. Conclusions**

In the past 20 years field testing experiences have been obtained with damped AC testing. For several years now, this technology has also been applied to testing submarine cables at o ffshore wind farms. Besides this, the basic aspects of failure risks of export and inter-array cables for o ffshore wind farms have been discussed in this contribution. The following conclusions may be drawn after-installation testing:

**Author Contributions:** Conceptualization, R.J. and E.G.; validation, R.J. and E.G.; investigation, R.J.; data curation, R.J.; writing—original draft preparation, K.S., R.J., and E.G.; writing—review and editing, A.R. and K.S.; visualization and data submission, R.J.; supervision, E.G.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The authors declare no conflict of interest.


**4.2 GLOF events associated with surging of glaciers**

*Glaciers and the Polar Environment*

Kunming, China, and ICIMOD. The remote sensing and field observations

**Year Event date Glacier River Influencing factors**

1999 6 August Khalti/Gupis Gilgit Moonsoon rainfall 2000 10 June Shimshal Hunza High temperature 2000 27 July Kand/Hushe Indus Moonsoon rainfall

 5 April Ghulkin Hunza Western disturbance 6 January Passu Hunza Western disturbance 2 April Ghulkin Hunza Western disturbance 22 May Ghulkin Hunza Persistent rainfall 24 May Ghulkin Hunza Persistent rainfall 14/15 June Ghulkin Hunza Heat wave

2009 26 March Ghulkin Hunza Western disturbance

2018 17 July Barsuwat glacier Immit Heat wave 2019 23 June Shishper Hunza High temperature 2020 29 May Shishper Hunza High temperature

 — Batura Hunza — — Batura Hunza — — Balt Bare Hunza — September Darkot/Barados Gilgit — July Sosot/Gupis lake Gilgit —

2005 July Sosot/Gupis lake Gilgit

analysis of Khurdopin glacier provides up to date evidence about glacier surge and its possible impacts on the downstream populations because of the newly devel-

Glacial lakes formation depends on the type of glacier, its slope, and geological settings. For example, a supraglacial lake creates on the surface of glaciers when its slope is less than 2%. Similarly, surging glaciers block the river valley and cause the formation of the lake. Moreover, moraine-dammed lakes develop due to the advancement or recession of valley glaciers. Overall, these GLOF events depend on the physical and topographical conditions and the nature of damming materials. The severity of damages increases as the elevation and the volume of the glacial lakes increases. The type of moraine-dammed and the surging glaciers are the most dangerous types that block the valleys and cause GLOF events in the basin. In this regard, the type of GLOF event for the glaciers in the Hunza Basin is also not the same for example; Passu glacier caused damage due to outbursts of the end-moraine dammed lake, supra-glacial lake outburst occurred from Ghulkin and Hispar glaciers, valley blocked by Khurdopin glacier. GLOF from these glaciers bring rocks and the mudflows in the glacial streams,

for example, significant mudflows released from Batura glacier.

**110**

oped lake.

**Table 2.**

**4. Results and discussion**

**4.1 GLOF events in Hunza basin**

*History of major GLOF events in CPEC region.*

The surging activities of the glaciers in the Hunza Basin have also been interpreted by earlier studies [14, 32, 33] from a stable or slightly increasing trend of snow cover for the Hunza River basin [1, 25]. It has been reported recurrent surges for several glaciers of the Hunza Basin [6]. For example, Bolch et al. [20] and Quincy and Luckman [34] have comprehensively reported the surge history of Khurdopin glacier. The glaciated area of Khurdopin glacier is 115 km2 which is situated in Shimshal River, a tributary of the Hunza River. The first surge has been reported in 1979 and the second surge event occurred in 1999 and both surge events occurred in the summer season. The latest surge was observed during the summer season of 2017 [35]. These events suggest the return period of the surge event for Khurdopin glacier is about 20 years. No significant change has been observed in the debris cover Hispar and Shimshal glaciers of the Hunza basin for the period of 1977–2014 [36]. It was determined that this might be due to balanced glacier budgets during this period. Type of glaciers and their areas are given in **Table 1**.

The surging of Khurdopin glacier has resulted in the formation of the mediumsized ice-dammed lake at an elevation of 3454 m a.s.l and it lies at latitude-longitude of 36°21′007″ N and 75°27′51.2″ in the Shimshal River valley of the Hunza basin. Khurdopin lake started to surge in the first week of May 2017 and it has been greatly expanded in terms of size and depth and it became vulnerable to breach as witnessed by the local people. Due to the short distance between the glacier and opposite hard mountain resulted in the rise of river bed and glacier as well as triggering the creation of Khurdopin lake. The velocity of the flow was reduced by the damming of water behind the barrier and this phenomenon also raised the river bed and blocked the river (**Figures 2** and **3**).

**Figure 2.** *Comparison of different glaciers area loss during the period of 1977–2014.*

#### **Figure 3.**

The glacier areas of different glaciers were compared, which mostly thinned in terms of area or remain constant during the different periods. The area of Batura glacier was 380 km2 in 1977 as compared to 351 km2 in 2014, respectively. The loss of the area was 7.63% during this period. However, the glacier area loss was observed about 4.69% between 1999 and 2014. The glacier area was reduced to 369 km2 till 1999 and lost 2.89% of the glacier area as compared to 1977. The loss in glacier area was increased by up to 7% in 2014 as compared to 1999. The increment of a 4% loss in glacier area was due to an increase in temperature. During 2001 and 2007, the loss of glacier area was consistent, but it was observed 4.2% in 2009 as compared to 1977. Passu glacier area loss observed 10% from 1977 to 2014. The loss of the area was less than 1% for 1999 as compared to 1977. The rate of loss of the glacier area increased in 2001 and reached up to 3% but this rate reached up to 7% in 2007. The lake formation also fluctuated during this period. The number of GLOF and historical events was also observed during this period. Ghulkin glacier also lost its area up to 4% due to global warming from 1977 to 2014. Earlier 2000, Ghulkin glacier lost the area less than 1.5%. After 2 years, the loss of the glacier area was 6%. From 2001 to 2007, the melting of glacier and loss of its area remained constant but the rate of glacier area loss was reduced up to 4% in 2009. Ghulmit glacier lost its area about less than 2% before 2000. The loss of the glacier area in 2001 was 4% but it increased up to 5% in 2007. This glacier area was reduced to 3% in 2009 as compared to 2007 (**Table 3**).

#### **4.3 Drifting mechanism of glaciers**

Due to differential movement of glaciers, crack or rift is produced in the glaciers having connected snout. A rift was formed along the left part of the Khurdopin glacier due to collapsing and crushing of glacier all together. The Yukshin Girdan glacier played a role of strong obstruction, produced massive frictional forces, and initiated the glacier ice to break down at the rift area into pieces of ice bergs that were seen floating on the newly formed lake. During this process, the Khurdopin glacier was forced by the Yukshin Girdan glacier to move toward the right side because of the unavailability of an obstacle to the opposite mountain. The elevation of the glacier at the rift area was about 3558 m a.s.l. The glacier was covered by a huge amount of debris during 2015, and after this surge, the debris began to falling

**113**

*Risks of Glaciers Lakes Outburst Flood along China Pakistan Economic Corridor*

4 Hispar Surge type

6 Khurdopin Debris cover

7 Vijerab Debris cover

*List of selected glaciers and their types in Hunza basin [20].*

**Sr.# Glacier name Glacier type Area (km2**

Debris cover

Surge type

Surge type

1 Batura Debris cover 236 2 Passu Debris free 51 3 Barpu Surge type 90

5 Yazghil Debris cover 99

**)**

345

115

113

and sliding into the crevasses and impacted the sub-glacial water movement and that may further result in the formulation of a new sub-glacial lake [25, 34].

Whole region 2868

The meltwater released from the Vijerab glacier was blocked by the Khurdopin glacier and it was muddy because of high sediment load coming from the glaciated area. A large amount of water was flowing through the newly developed crevasses due to the presence of barriers and ultimately outflowing through the cave type snout of Khurdopin glacier. The phenomenon of ice block falling in the stream of Vijerab glacier and on the supra-glacial lakes was also perceived. Because of surging effects, glacier deforms and results in the formation of huge crevasses. Three main types of crevasses developed in Khurdopin glacier are listed below: irregular crevasses, longitudinal crevasses, and transverse crevasses. Due to the demolishing action of glaciers, most of the crevasses were found to be irregular in shapes. Due to glacier advancement, large numbers of crevasses were developed all over the glacier. The width of the crevasses was variable at different locations and mostly, it ranged

The heterogeneous behavior and close-to balanced budgets are not a recent phenomenon in Hunza Valley (Karakoram). We have observed that the geodetic mass budgets computed from the 1973 KH-9 and 2009 ASTER DTMs are in covenant with the results of the individual periods 1973–1999 and 1999–2009 without indefinite radar penetration correction: since the 1970s, the glaciers in this region underwent slight and insignificant mass loss. Though, the differences may exist in individual glaciers for the two studied periods. Overall, we can confirm that the surge-type and non-surge-type glaciers are not significantly different with respect to mass change inferred from the 40 years observations of glaciers in the

One can easily assess the flood damages from recently developed lakes if it bursts based on watermarks of previous flood events. Besides, the bursting mechanism and the volume of flood events can give us an insight into the damages in the downstream areas. The water level in the lake can provide us information about the GLOF impacts on downstream infrastructure. The GLOF will have devastating impacts on the infrastructure including homes, lands, schools, etc. The settlement along the

river site could be adversely affected as a result of GLOF (**Figure 5**).

*DOI: http://dx.doi.org/10.5772/intechopen.93459*

between 1 and 2.0 m [20, 35].

**Table 3.**

Karakoram (**Figure 4**).

**4.4 Geodetic mass balance of surging glaciers**

*Risks of Glaciers Lakes Outburst Flood along China Pakistan Economic Corridor DOI: http://dx.doi.org/10.5772/intechopen.93459*

#### **Table 3.**

*Glaciers and the Polar Environment*

glacier was 380 km2

in 2009 as compared to 2007 (**Table 3**).

**4.3 Drifting mechanism of glaciers**

369 km2

**Figure 3.**

The glacier areas of different glaciers were compared, which mostly thinned in terms of area or remain constant during the different periods. The area of Batura

till 1999 and lost 2.89% of the glacier area as compared to 1977. The loss in

loss of the area was 7.63% during this period. However, the glacier area loss was observed about 4.69% between 1999 and 2014. The glacier area was reduced to

glacier area was increased by up to 7% in 2014 as compared to 1999. The increment of a 4% loss in glacier area was due to an increase in temperature. During 2001 and 2007, the loss of glacier area was consistent, but it was observed 4.2% in 2009 as compared to 1977. Passu glacier area loss observed 10% from 1977 to 2014. The loss of the area was less than 1% for 1999 as compared to 1977. The rate of loss of the glacier area increased in 2001 and reached up to 3% but this rate reached up to 7% in 2007. The lake formation also fluctuated during this period. The number of GLOF and historical events was also observed during this period. Ghulkin glacier also lost its area up to 4% due to global warming from 1977 to 2014. Earlier 2000, Ghulkin glacier lost the area less than 1.5%. After 2 years, the loss of the glacier area was 6%. From 2001 to 2007, the melting of glacier and loss of its area remained constant but the rate of glacier area loss was reduced up to 4% in 2009. Ghulmit glacier lost its area about less than 2% before 2000. The loss of the glacier area in 2001 was 4% but it increased up to 5% in 2007. This glacier area was reduced to 3%

Due to differential movement of glaciers, crack or rift is produced in the glaciers having connected snout. A rift was formed along the left part of the Khurdopin glacier due to collapsing and crushing of glacier all together. The Yukshin Girdan glacier played a role of strong obstruction, produced massive frictional forces, and initiated the glacier ice to break down at the rift area into pieces of ice bergs that were seen floating on the newly formed lake. During this process, the Khurdopin glacier was forced by the Yukshin Girdan glacier to move toward the right side because of the unavailability of an obstacle to the opposite mountain. The elevation of the glacier at the rift area was about 3558 m a.s.l. The glacier was covered by a huge amount of debris during 2015, and after this surge, the debris began to falling

in 2014, respectively. The

in 1977 as compared to 351 km2

*Temporal variation in areas of different glaciers along CPEC.*

**112**

*List of selected glaciers and their types in Hunza basin [20].*

and sliding into the crevasses and impacted the sub-glacial water movement and that may further result in the formulation of a new sub-glacial lake [25, 34].

The meltwater released from the Vijerab glacier was blocked by the Khurdopin glacier and it was muddy because of high sediment load coming from the glaciated area. A large amount of water was flowing through the newly developed crevasses due to the presence of barriers and ultimately outflowing through the cave type snout of Khurdopin glacier. The phenomenon of ice block falling in the stream of Vijerab glacier and on the supra-glacial lakes was also perceived. Because of surging effects, glacier deforms and results in the formation of huge crevasses. Three main types of crevasses developed in Khurdopin glacier are listed below: irregular crevasses, longitudinal crevasses, and transverse crevasses. Due to the demolishing action of glaciers, most of the crevasses were found to be irregular in shapes. Due to glacier advancement, large numbers of crevasses were developed all over the glacier. The width of the crevasses was variable at different locations and mostly, it ranged between 1 and 2.0 m [20, 35].

#### **4.4 Geodetic mass balance of surging glaciers**

The heterogeneous behavior and close-to balanced budgets are not a recent phenomenon in Hunza Valley (Karakoram). We have observed that the geodetic mass budgets computed from the 1973 KH-9 and 2009 ASTER DTMs are in covenant with the results of the individual periods 1973–1999 and 1999–2009 without indefinite radar penetration correction: since the 1970s, the glaciers in this region underwent slight and insignificant mass loss. Though, the differences may exist in individual glaciers for the two studied periods. Overall, we can confirm that the surge-type and non-surge-type glaciers are not significantly different with respect to mass change inferred from the 40 years observations of glaciers in the Karakoram (**Figure 4**).

One can easily assess the flood damages from recently developed lakes if it bursts based on watermarks of previous flood events. Besides, the bursting mechanism and the volume of flood events can give us an insight into the damages in the downstream areas. The water level in the lake can provide us information about the GLOF impacts on downstream infrastructure. The GLOF will have devastating impacts on the infrastructure including homes, lands, schools, etc. The settlement along the river site could be adversely affected as a result of GLOF (**Figure 5**).

**Figure 4.** *Khurdopin Glacial Lake formation.*

**Figure 5.**

*Contribution of hazardous share in different glaciers along CPEC.*