Comparative life-cycle assessment of water supply pipes made from bamboo vs. polyvinyl chloride

Journal of Cleaner Production 240 (2019) 118172

Contents lists available at ScienceDirect

Journal of Cleaner Production journal homepage: www.elsevier.com/locate/jclepro

Comparative life-cycle assessment of water supply pipes made from bamboo vs. polyvinyl chloride Sheldon Q. Shi a, *, Liping Cai a, Yun Weng b, Dong Wang b, Yuanping Sun b a b

Mechanical and Energy Engineering, University of North Texas (UNT), Denton, TX, USA Zhejiang Xinzhou Bamboo-based Composites Technology Co., Ltd, China

a r t i c l e i n f o

a b s t r a c t

Article history: Received 17 February 2019 Received in revised form 1 August 2019 Accepted 25 August 2019 Available online 26 August 2019

Bamboo is one of earth's most plentiful natural materials and provides a high-quality alternative to many other raw materials. Utilizing bamboo can help to curtail global warming by decelerating the destruction of forests because it can be a good alternative to wood in its various applications. Bamboo winding composite pipe is a new developed product for water supply application. Life-cycle assessment is a tool used to evaluate the environmental impacts for the use of bamboo in pipes considering all stages of a water pipe's life from raw material extraction to the end of pipe life. In this study, the environmental impacts of polyvinyl chloride pipe and bamboo winding composite pipe were compared using SimaPro (Version 8.5) software. The results demonstrated that, all major indices of environmental impacts (except for the Eutrophication index) were significantly reduced by 1.1e488.8 times when bamboo winding composite pipes were used to replace polyvinyl chloride pipes for the water supply system. In addition, when the bamboo pipe was used to replace the polyvinyl chloride pipe, the cumulative energy demands were reduced by 3.40 times and the total environmental burdens (eco-indicator 99 points) were reduced by 7.19 times. The Building for Environmental and Economic Sustainability index (which is represented by equivalent CO2 uptake value in SimaPro software) was used to compare the different life cycle stages affecting environments. The results showed that the eq.CO2 index for the stage of production of bamboo winding composite pipe was 5.35 times of that of the stage of waste pipe disposal/degradation. In addition, the environmental impacts of six raw materials for the bamboo winding composite pipe (per functional unit), i.e., bamboo slivers, modified urea-formaldehyde resin, filling powder of walnut husk, Styrene E, cotton textile and bamboo fiber fabric, were compared using the eq.CO2 index. It was discovered that the urea-formaldehyde resin, Styrene E and cotton textile took the major parts affecting environment. The sensitivity analysis results indicated that the environmental impacts could be further reduced if 10% Styrene E and urea-formaldehyde was replaced with bamboo slivers. As a conclusion for this study, the major environmental impact indices were significantly reduced when the bamboo winding composite pipe was used to replace polyvinyl chloride pipe. Published by Elsevier Ltd.

Handling Editor: Prof. S Alwi Keywords: Bamboo winding composite pipe Polyvinyl chloride pipe Environmental impact indices Cumulative energy demands Total environmental burdens

1. Introduction Life-cycle assessment (LCA) can be used to assess the ecological influences in all stages in a water pipe's life including raw material extraction, material processing, pipe manufacturing, transportation, installation, maintenance, and disposal or recycling (Akhtar et al., 2015). The analysis results can be used to improve processes of pipes, support policy management and provide decision makers with a detailed basis of pipe materials, production and

* Corresponding author. E-mail address: [email protected] (S.Q. Shi). https://doi.org/10.1016/j.jclepro.2019.118172 0959-6526/Published by Elsevier Ltd.

disposal strategy. The procedures of LCA are defined by ISO Environmental Management Standards, e.g., ISO 14040 (2006) and ISO 14044 (2006). Recent studies used LCA to analyze environmental impacts of biomass composite products, e.g., polyurethane (PU)-reinforced kenaf panels (Batouli et al., 2014), kenaf fiber reinforced cement panels (Zhou et al., 2018), kenaf fiber-sheet molding compound (Wu et al., 2018), isolation and characterization of nanocrystalline cellulose from sugar palm fibres (Ilyas et al., 2018a), sugar palm nanocrystalline cellulose reinforced sugar palm starch bionanocomposites (Ilyas et al., 2018b), sugar palm nanocrystalline cellulose reinforced bionanocomposites (Ilyas et al., 2019), etc.

2

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

However, limited studies were found for pipe system analysis by LCA. Water supply pipe systems play an important role in municipal infrastructure, and LCA results can be used for selecting the optimal water pipe systems to achieve the least impact on environments. LCA considers all phases in the life of water pipes that cause environmental and economic impacts, from the pipe material extraction to the pipe service/disposal (Lippiatt and Boyles, 2001). The pipe network collects wastewater from buildings and transports the water to disposal sites, making up major components of cites’ undergrounds. As bloodlines of modern cities, the life cycle of sewerage pipe systems cause substantial environmental impacts (Halfawy et al., 2008). Historically, during the water pipe system design phase when pipe materials were selected, the main priority of selection targeted maximum economic benefit (Mirza, 2007), while environmental and social impacts remained largely unconsidered. The PVC and glass-fiber materials could be considered as the cost-effective pipe materials for replacing ordinary ductile iron and concrete materials due to the technical benefits in pipe transportation, installation and service stages (Turner, 2007). However, due to the increasing concerns of climate change, there is a need to develop more environmentally friendly biomass materials for creating and maintaining water pipe systems (Faria and Guedes, 2010). Being developed by Zhejiang Xinzhou Bamboo-based Composites Technology Co., Ltd, China, in 2007, the bamboo winding composite pipe is made from bamboo and resin using winding technology. With its many excellent advantages of renewable, low weight and high strength, low cost, low carbon and low energy consumption during production and service processes, the bamboo winding pipe fully utilizes the high axial tensile strength property of bamboo fibers, and is a promising alternative pipe for replacing traditional PVC pipes. Thus, there is a need to evaluate the environmental performance of the bamboo winding pipes. This study aimed to analyze two types of water pipes, namely, the bamboo winding composite pipe and PVC pipe using the SimaPro 8.5 LCA software, to provide decision makers with a guideline for the water supply system selection. To achieve better life cycle performance, this study examined major stages of a water pipe's life, including a) raw material acquisition (e.g. bamboo harvesting and transportation to pipe manufacturing sites); b) bamboo and resin processing; c) pipe manufacturing, transportation and installation; d) water pipe service and maintenance; and e) waste pipe disposal, recycling, landfills, etc. 2. Materials and methods This section includes summarized previous studies for water pipe materials and software programs used for pipe LCA, LCA input information for bamboo and PVC pipes, LCA evaluation and life cycle inventory (LCI) methods. 2.1. Previous studies for water pipe materials and software programs used for LCA

such as polyethylene, PVC, ductile iron, polypropylene (PP) and concrete were investigated by Recio et al. (2005). The results showed that, when energy consumption and CO2 emission were considered, PE and concrete could be the most favorable piping materials. Environmental impacts of four sewer pipe materials, i.e., concrete, PVC, vitrified clay, and ductile iron, were examined by Akhtar et al. (2015). Firstly, as an equivalent form of solar energy (a solar emergy joule), a term “emergy” was defined by combining the environmental analysis and economic analysis. Then, the analytical pyramid method was utilized to combine the environmental and economic analyses and optimize the water pipe life cycle. The results concluded that the PVC pipe was the most “ecological friendly” in terms of environmental and economic sustainability. The published projects of water pipe LCA, materials as well as the software programs they used were summarized and are presented in Table 1. The previous description of the utilization of LCA for water pipes and the data in Table 1 demonstrated that the manufacturing process and application of water pipes have a great impact on the environment. It is necessary to use LCA to evaluate the raw materials and manufacturing process of water pipes in order to select the appropriate materials and production processes to reduce negative impacts to the environment. In addition, although prior studies have been conducted using LCA assessments of city water pipes for a wide range of materials, no LCA assessments of bamboo winding pipes have been carried out. Akhtar et al. (2015) compared environmental and economic impacts of four raw materials, i.e., concrete, PVC, vitrified clay, and ductile iron and pointed out that the PVC pipe was the most sustainable piping. Thus, the PVC pipe was used to compare with the bamboo winding composite pipe during the LCA process in this study. SimaPro software is currently one of the most widely used software packages in LCA processes (Herrmann and Moltesen, 2015), which was selected for the pipe LCA evaluation in this study. 2.2. Life cycle inventory (LCI) According to ISO 14040 (2006), at the stage of life cycle inventory, the functional units and the LCA system boundaries for both bamboo wind pipe and PVC pipe were defined, and all input data were collected as shown in Table 2. The data about the raw materials and energy flows was derived from the Ecoinvent database in the SimaPro software and local investigation in China. The collected data and energy flows included the raw material production (bamboo, MUF resin, walnut husk, Styrene E, cotton textile and bamboo fiber). The transportation was assumed using Euro 30ton truck. The production data of the bamboo slivers was obtained from the Ecoinvent database as a product, which together with coproducts of bamboo green skin part, bamboo residues and dust. Data of other raw materials was also obtained from the Ecoinvent database. 2.3. LCA inputs for bamboo winding composite water pipe

The emission of greenhouse gas (GHG) is one of the most important factors affecting the environment. It was reported that GHG emission of the manufacturing of ductile iron pipes was 15 times higher than that of concrete pipes because the zinc coating caused considerable energy consumption (Venkatesh et al., 2009). Although the manufacturing of plastic pipelines had much more significant GHG emissions than those of concrete pipes, PVC or polyethylene (PE) pipelines were still the most suitable materials due to their low cost, good ductility, and small pipe diameter capability (Venkatesh et al., 2009). In addition, the GHG emission and energy consumption of pipes made from different materials

An extensive application of bamboo is helpful for conserving forestry without demanding much wood from consumers for construction and furniture. The city can obtain dual benefits from the using of bamboo pipes, i.e., having an excellent water supply system and supporting a stable ecosystem. Bamboo winding composite pipe is a newly developed product for water supply application by the Zhejiang Xinzhou Bamboo-based Composites Technology Co., Ltd. in China as shown in Fig. 1 (a. in the exhibition hall of the pipe production mill and b. in the installation site). The bamboo winding composite water supply pipe is the first

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

3

Table 1 Previous studies for water pipe materials and software programs used for LCA. Authors

Type of pipe

Topic

Dennison et al. (1999) Friedrich et al. (2007) Halfawy et al. (2008) Venkatesh et al. (2009) Herstein and Filion (2011) Akhtar et al. (2015) Erses Yay (2015) Vahidi et al. (2016) Petit-Boix et al. (2016) Asadi et al. (2016)

Ductile iron and medium density polyethylene

To examine the effect of two pipe materials on n/a the environment

Software

Results Extension of material recovery or reuse could benefit environment

Water supply, treatment and recycling

To evaluate water industry using LCA

n/a

The energy for treatment of water and wastewater takes the highest environmental burdens.

Sewer pipes

Optimal plan to renew city sewer networks

GIS and GIS-based supporting system

The GIS-based supporting system can help improve renewal planning of sewer networks.

Concrete, steel, and PVC pipelines Pipeline Networks were analyzed using MFA- LCA-MFA (Material LCA flow analysis)

Phases of pipe manufacturing and maintenance were the major factors affecting gas emissions

Ductile iron (DI) and PVC pipes, as Explore impacts of economy and environment Non-dominated well as steel tanks of the two pipes and the tank. sorting genetic algorithm (NSGAII)

Production of DI and PVC pipes had more severe environmental impacts than that of steel tank

Concrete, ductile iron, PVC and vitrified clay pipes

To compare environmental impacts of pipe materials

PVC pipe is the most sustainable one

Municipal solid wastes including water pipes Fiber þ polymer, PVC, ductile iron, polyethylene, vitrified clay and concrete Concrete, PVC and high-density polyethylene (HDPE) pipes with different designs Cross-linked polyethylene (PEX) and copper pipes

Using LCA to compare environmental impacts SimaPro 8.0.2 of different municipal solid wastes To compare LCA of sewer pipe materials SimaPro

LCA is a powerful technique to assist waste management The ductile iron was the worst option and the reinforced concrete was the best one.

Structural analysis and LCA of sewerage pipe SimaPro 7.2.0 systems

The design of plastic pipes embedded in concrete had better environmental performance.

SimaPro 7.1

The impacts of economy and environment of SimaPro 8.0 the two pipes were compared by LCA.

The total cost of the building was reduced by 63% when PEX piping was used to replace the copper piping. LCIA method (CML 2 DI and steel had more significant ecological Hajibabaei Five pipe materials: PVC, HDPE, DI, LCA of pipe service and manufacturing for fibrocement, and steel drinking water networks et al. baseline2000) impacts than PVC, HDPE, and fibrocement pipes (2018). during the manufacturing The asbestos cement pipe had more significant Loss et al. Relining water pipelines Comparison of relining methods of pipelines, SimaPro 7.3.2 environmental impact than that of the pig iron pipe (2018) i.e., traditional open cut and pipe bursting systems using LCA.

Table 2 Input data for bamboo winding composite pipe and PVC pipe.

Felling of bamboo

Transportation from the forest to bamboo sliver mill Production of bamboo slivers for pipe

Bamboo pipe

PVC pipe

 1.25 tons of bamboo was felled to produce 1 t bamboo trunk.  The chainsaw production rate of 10 tons of bamboo per person per day, counting for 42 min per ton.  It needed 52.5 min of chainsaw use for the 1.25 tons bamboo. Transport distance of 5 km using the 4-8-ton truck.

The impacts of the raw materials and production process of PVC pipe on the environment was directly utilized the information from the database in SimaPro, and the main inventory data for PVC pipe production are as follows: 973 kg Air, 408 kg Carbon dioxide, 84 kg Calcium carbonate, 6.4 GJ Energy, 112 kg water.

 Bamboo slivers, 12% of the output  Bamboo residues and dust, 80% of the output  Bamboo green skin part (skin part), 8% of the output Raw materials for one function unit of pipe 24 kg bamboo slivers and 41 kg MUF resin, 6 kg powder of walnut husk, 7 kg unsaturated resins (Styrene E), 3 kg mesh cloth (cotton textile) and 3 kg bamboo fiber fabric approximately, counting 84 kg in total Electricity for pipe manufacturing 25 kwh per function unit Transportation from bamboo sliver 500 km using the 30-ton truck. Since one function unit was manufacturer to bamboo pipe manufacturer 24 kg for bamboo slivers, it was calculated as 500 km  (24 kg/1 ton) ¼ 12 tkm Transportation from the pipe manufacturer to 500 km using 30-ton truck. Since the weight of the bamboo 500 km between the PVC pipe manufacturer and the pipe pipe installation site pipe with 800 mm diameter and 1-m long was 84 kg, it was installation site using 30-ton truck. Since the mass of the PVC pipe was 84 kg, it was calculated as 500 km  (84 kg/1 calculated as 500 km  (84 kg/1 ton) ¼ 42 tkm ton) ¼ 42 tkm Energy consumption for installing 1-m pipe 4.2 L diesel, counting for 3.675 kg of diesel 4.2 L diesel, counting for 3.675 kg of diesel Transportation from the pipe disposal site to 50 km using 10-ton truck, counting for 4.2 tkm 50 km using 10-ton truck, counting for 4.2 tkm the landfill site Raw materials included PVC resin, calcium carbonate, The system boundaries designed as a ‘gate-to- The extraction of bamboo, production of raw materials, production of pipes, pipe installation and services, all related stabilizer, etc., extruder, production of PVC pipes, pipe grave’ LCA, because the harvesting of installation and services, all related transport and the final bamboo was considered as a starting point. transport and the final disposal or recycling as shown in disposal or recycling as shown in Fig. 3. Fig. 2.

4

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

a

b

Fig. 1. The bamboo winding composite pipes in (a) in exhibition hall and (b) installation site.

partially bio-based pressure pipe. It serves as an alternative to traditional materials used in the manufacturing of pipes such as metals, plastics, and fiber-glass reinforced plastics. The bamboo water supply pipe is a multi-layered pipe that is processed through high tension winding, and is constructed mainly from the bamboo curtain and modified urea-formaldehyde (MUF) resin. Using SimaPro software package, Wilson (2009) evaluated a life-cycle inventory (LCI) of the manufacturing of resins used for woodbased composites in the U.S. Four types of resins, e.g. ureaformaldehyde and melamine-urea-formaldehyde, were investigated. The bamboo curtain is made from bamboo slivers. The manufacturing process for the bamboo winding composite pipe consists of bamboo curtains that are reinforced with MUF resin, which are then fed through a mechanical arch-shaped winder. The arch shaped winder takes advantage of the high axial tensile strength of bamboo by winding the bamboo without adding stress defects. Bamboo curtains are wound about a metal drum to create the pipe seepage control layer and the structure layer. After the resin is cured, the mold is then removed. According to ISO standards (ISO 1040), the function unit is required to be defined as a reference to the system performance during the LCA process. In this study, LCA was conducted for two materials including bamboo and polyvinyl chloride (PVC) of water supply pipes. The strength of water pipe, namely, pipe ring-stiffness (Sp) plays a major role in regards to its function in service. A general approach for comparing different material components with equal mechanical strength (Khanna and Bakshi, 2009) or Sp was used to define the functional unit. The approach was previously used to define the functional unit in a similar LCA study (Korol et al., 2016). Sp of pipe can be calculated as (Zhao and Yao, 2012):

Sp ¼

EIp 8R

3

is the inner radius of pipe; r is the material density, kg/m3; t is the thickness of pipe (t ¼ R-r), m. From Eqs. (1) and (2), the pipe mass can be obtained as,

m ¼ 2ptlr

sffiffiffiffiffiffiffiffi 3 EIp 8Sp

According to its function in the water line, the functional unit for the bamboo winding pipe was defined as a one-m long and 800mm diameter of water pipes (PN1.0, Chinese Standards) with the same design life of 56 years, which was provided by the manufacturer according to their accelerated ageing test. In this project, the functional unit of the bamboo winding composite water pipe mainly comprised six materials, i.e. 24 kg bamboo slivers and 41 kg MUF resin, 6 kg powder of walnut husk, 7 kg unsaturated resins (Styrene E), 3 kg mesh cloth (cotton textile) and 3 kg bamboo fiber fabric approximately, counting 84 kg in total. The LCA process of bamboo winding composite pipe took into account the entire pipe life-cycle of the functional unit, including the bamboo production with bamboo harvesting, decortication, splitting, drying and curtain making, resin component production (data provided by the SimaPro software), transportation and use phase, and disposal (Fig. 2). The scope involved inputs of bamboo and resin materials and emissions from all reagents and raw materials, as well as extraction, conversion and transport of energy inputs during the manufacturing and transportation. The life cycle analysis procedure for bamboo winding composite pipe was included in three major process steps, as shown in Fig. 2. The first process of LCA was the felling of bamboo. The subproject “Felled Bamboo” was made for SimaPro software. The LCA

(1)

where, Sp is the pipe ring-stiffness, kPa; E is the modulus of elasticity, kPa; Ip is the moment of inertia, m4/m; R is the average radius of pipe, m, i.e., R ¼ (R þ r)/2. The mass (m) of the pipe is written as:


 m ¼ p R2  r 2 rl ¼ 2pRtlr

(2)

where, m is the mass of pipe, kg; R is the outside radius of pipe, m; r

(3)

Fig. 2. Steps in bamboo winding composite pipe life cycle.

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

evaluation for bamboo pipe in this study began with the initial phase of bamboo harvesting. According to the real bamboo cutting, collection and transportation practices, the estimated input information were as follows:  1.25 tons of bamboo was cut to make 1 ton bamboo trunk, and leaves and tops of the bamboo were left on the forest ground to decompose naturally. Because the leftover bamboo was part of one of the natural processes in the forest recycling, it was assumed that the bamboo cutting would not cause increased emissions on the forest ground.  A chainsaw was used for cutting the bamboo. The cutting data was specified as a production rate of 10 tons of bamboo per person per day (seven working hours per day), counting for 42 min per ton. This means that it needed 52.5 min of chainsaw use for the 1.25 tons of raw bamboo. The second process of LCA was the pipe manufacturing process, where bamboo was turned into yellow slivers, green skin parts, and bamboo dust. Based on the bamboo sliver production mill practice, this process converted the felled bamboo into three products as follows:  Bamboo slivers, 12% of the output  Bamboo residues and dust, 80% of the output  Bamboo green skin part (skin part), 8% of the output The transportation activity between the location of growing bamboo and the manufacturing mill was considered. Just as in the case of the chainsaw, an existing process in SimaPro for producing the environmental load from a truck transportation was used. The impacts of the transportation and energy consumption were added to the LCA process. It was assumed a distance of 5 km between the bamboo growing site and the bamboo sliver production mill using the 4-8-ton truck. The electricity consumption for the manufacturing of bamboo slivers of one-m long and 800-mm diameter pipe was assumed to be 25 kwh. The third process of LCA was the waste treatment and waste scenarios. The characteristics of the scenario was that 100% of the bamboo winding composite pipes was dumped in a landfill place. It was assumed that the landfill had a collection system for methane, in which, 30% of the emitted methane was used as fuel. According €nder et al., 2014), there was no signifito previous studies (Vogtla cant difference of the carbon sequestration in the waste treatment between wood and bamboo. Thus, the wood waste scenario data in SimaPro software was used for estimating the impact of bamboo on environments during the landfill scenario. Landfilled bamboo is slow to degrade and does create methane and CO2 in the first 150 years of decomposition. Approximately 20% of the bamboo pipe cannot be decomposed and remain in the land as a stable earth material (Vogtl€ ander et al., 2014). According to information provided by the bamboo manufacturer, the following transport distance and energy consumption estimates are as follows:  It was assumed a transport distance of 500 km between the bamboo sliver producers to the bamboo pipe manufacturingmill using the 30-ton truck. Since the function unit in this project was 24 kg bamboo slivers, it was calculated as 500 km  (24 kg/1 ton) ¼ 12 tkm.  The distance between the pipe manufacturer and the bamboo winding composite pipe installation site was 500 km using 30ton truck. Since the weight of the bamboo winding composite pipe with 800 mm diameter and 1 m long was 84 kg, it was calculated as 500 km  (84 kg/1 ton) ¼ 42 tkm;

5

 The energy consumption for installing 1 m pipe was assumed to be 4.2 L diesel, counting for 3.675 kg of diesel;  The transport distance between the municipal waste collection center and the landfill site was 50 km using 10-ton truck, counting for 4.2 tkm;  After the service ages, the bamboo winding composite pipes could be ground to powder and recycled for other reuses.

2.4. LCA inputs for PVC pipe The PVC pipe used for LCA was PN1.0 (Chinese Standards) pipe with the mass of 84 kg as a functional unit. The LCA of the PVC pipe in this study is shown in Fig. 3. By considering pipe disposal phases, LCA of the PVC pipe was undertaken all the life stages including materials, manufacturing, transportation, installation, service and disposal. The overall impacts of the PVC pipe included the production of PVC pipe, as well as its application and disposal stages. In the PVC production process, ethylene dichloride is produced by combining ethylene and chlorine, which is an intermediate product. Then the ethylene dichloride is converted into vinyl chloride, which was the basic block of PVC (Akhtar et al., 2015). Based on the eco-profile data (PlasticsEurope, 2018, accessed on 25 July 2018) for general purposes, plastics contain no significant difference in energy consumption from extraction of oil to plastic production between PVC and the other plastics. However, since SimaPro software provides information regarding the PVC production and its environmental-related data during the LCA process, the data from the SimaPro software was utilized in this study. The transportation and some emissions for PVC pipes were assumed as:  A distance of 500 km between the PVC pipe manufacturer and pipe installation site was travelled using 30-ton truck. Since the mass of the PVC pipe was 84 kg, it was calculated to be 500 km  (84 kg/1 ton) ¼ 42 tkm;  The energy consumption for installing pipe was 4.2 L diesel per functional unit, counting for 3.675 kg of diesel;  A distance between the solid waste collection place and the landfill site was 50 km using 10-ton truck, counting for 4.2 tkm. The input data of bamboo winding composite pipe and PVC pipe for LCA were summarized and are presented in Table 2. 2.5. Methods of LCA evaluation Considering three types of damages, i.e., human health, ecosystem quality and resource depletion, the technology of Building for Environmental and Economic Sustainability (BEES, Lippiatt, 2007) has been a commonly accepted methodology in the LCA field. The global warming potential is one of the characterization factors in BEES, which was developed in 2001 by the

Fig. 3. Steps in the PVC pipe life cycle (Akhtar et al., 2015).

6

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

International Panel of Climate Change (Lippiatt, 2007). The biogenic CO2 uptake is considered to have a negative impact in BEES. Therefore, BEES is represented by an equivalent CO2 uptake value in SimaPro software. In addition, the Eco-indicator 99 (the burden on the environment) is another effective LCA tool. One eco-indicator 99 point (Pt) is defined as 1/1000 of the annual environmental load from one average European person, being called as “normalization and weighting of the damage factors” (Goedkoop et al., 1999). Ecoindicator 99 also can be used for the product comparisons by considering all types of environmental damages. The purpose of examining the Cumulative Energy Demands is to estimate all of the energy input for the raw material acquisition (e.g. bamboo harvesting and transportation to pipe manufacturing sites); pipe manufacturing, transportation and installation; pipe service and maintenance; and pipe disposal, recycling, landfills, etc. Thus, the index of Cumulative Energy Demands is suited to determine and compare the energy intensity of PVC pipe and bamboo pipe processes. To systematically describe and assess environmental impacts using different characterization factors, three sets of environmental impact indexes, namely, BEES impact indexes, Eco-indicator 99 point and Cumulative Energy Demands, were used to evaluate the environmental impacts for two types of pipes in this study. The bamboo winding composite pipe was made from six major materials, i.e., bamboo slivers, MUF resin, styrene E, Cotton fibers, walnut husk powder, and bamboo fiber fabric. To evaluate the contribution of each component, environmental impacts of the six raw materials were examined using LCA. The sensitivity analyses was applies by evaluating alternative approaches, e.g., altering the quantities of raw materials and/or changing the transportation distance, during the production and service of bamboo pipes.

3. Results and discussion This section includes LCI of bamboo pipe, results examined using the BEES impact index method, Eco-indicator 99 method, cumulative energy demands method, and sensitivity analysis. 3.1. Inventory results All energy used and emissions occurred (the amount was over 10 g) of one functional unit of bamboo winding pipe production and waste pipe disposal were calculated and are listed in Table 3. The LCI result table is a list of consumption occurring over the life cycle of the bamboo pipe. The raw materials used are listed in Table 2. The LCI results were particularly useful without classification and characterization. The detailed results are described in the life cycle impact assessment in Section 3.2 to 3.4. 3.2. BEES impact index method The LCA results of bamboo and PVC pipes examined using the BEES impact index method are presented and analyzed as follows. 3.2.1. Results of analyses by BEES impact index Based on the calculation of BEES impact indexes (being presented by CO2 eq.) using the SimaPro software, the total environmental impacts of PVC pipes (the mass of 84 kg PVC pipe as a functional unit) are illustrated in Fig. 4. Fig. 4 shows that the BEES impact index produced by the manufacturing of PVC pipe was 2.72  105 CO2 eq., while the PVC pipe use/waste disposal process was 2.06  105 CO2 eq., indicating that the manufacturing process had 1.32 times higher environmental impact than that of the use/

Table 3 LCI results of bamboo winding pipe per functional unit. Substance

Unit

Total impact

Pipe production

Landfill

Air Aluminum Bamboo, unspecified, standing/kg Barite Biomass Calcite Calcium carbonate Calcium chloride Carbon dioxide, in air Clay, bentonite Clay, unspecified Coal, 26.4 MJ per kg Coal, brown Coal, hard Energy Gangue, bauxite, in ground Gas, natural, 46.8 MJ per kg Gas, natural/m3 Gravel Inert rock Iron Natural aggregate Nickel Nitrogen Oil, crude Oxygen Phosphorus Phosphorus Potassium chloride Sodium chloride Soil Water, cooling, salt, ocean

kg g kg g g g g pg kg g g g kg kg MJ g kg m3 kg kg g g g g kg kg g g g g g kg

41.32 12.87 37.50 46.03 35.12 592.18 227.16 115.09 16.58 14.11 124.71 615.71 1.31 4.00 872.33 133.94 8.25 4.21 13.48 11.66 618.70 325.36 17.03 911.76 9.87 4.91 27.17 12.43 151.24 48.67 79.08 1,003.47

41.32 5.03 37.50 16.48 35.12 387.41 227.16 115.09 15.47 8.80 78.26 615.71 0.41 3.28 861.84 50.67 8.25 3.79 6.46 11.66 309.46 325.36 8.91 855.15 2.60 4.89 27.16 12.33 151.17 41.16 79.08 1,003.47

0.00 7.84 0.00 29.55 0.00 204.77 0.00 0.00 1.11 5.31 46.46 0.00 0.90 0.72 10.50 83.27 0.00 0.42 7.012 0.00 309.24 0.00 8.11 56.62 7.27 0.03 0.01 0.10 0.07 7.51 0.00 0.00

Note: The amount of substance less than 10 g is not listed in this table.

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

7

in the figure, the BEES index of 41 kg UF resin was 1.83  104 eq.CO2, 7 kg Styrene E was 2.13  104 eq.CO2 and 3 kg cotton textile was 9.51  103 eq.CO2. The BEES indexes of other raw materials, namely, bamboo slivers, walnut shell powder and bamboo fiber fabric were very small, which could not be displayed in Fig. 5. The environment impact of bamboo winding composite pipe can be further reduced if the amount of the MUF resin, Styrene E and cotton textile were reduced. In addition, Fig. 5 presents the amount of CO2 eq. produced by the electricity consumption and transportation. 3.2.2. Comparison of PVC and bamboo winding pipes by BEES impact index After comparing Figs. 4 and 5, two findings regarding the LCA evaluations of BEES of the two types of pipes were obtained: a) the manufacturing process played a major role on the environmental impact, and. b) the PVC pipe produced much more impact on environment than that of bamboo winding composite pipe (4.95  105 g CO2 eq. Vs. 7.75  104 g CO2 eq.) as shown in Figs. 4 and 5.

Fig. 4. Network of the total environmental impact of PVC pipe (“1p” is one functional unit, “PVC pipe manufacturing” means the CO2 produced during the PVC pipe manufacturing process and the “Waste scenario for PVC pipe” means the CO2 produced during the PVC pipe use/disposal process).

disposal process. The total environmental impacts of bamboo winding pipes are shown in Fig. 5. The BEES impact index produced by the manufacturing of bamboo pipe was 6.53  104 CO2 eq., while the use/waste disposal process was 1.22  104 CO2 eq., indicating that the manufacturing process had 5.35 times higher environmental impact than that of the use/disposal process. The BEES impact indexes of the raw materials used in the production of bamboo winding composite pipe, including 24 kg bamboo slivers, 41 kg MUF resin, 6 kg filler (powder of walnut husk), 7 kg Styrene E, 3 kg cotton textile and 3 kg bamboo fiber fabric per functional unit, counting 84 kg in total, were compared using SimaPro software and the results are illustrated in Fig. 5. As shown

The LCA for the BEES environmental impact assessments of PVC and bamboo winding composite pipes were summarized and are presented in Table 4. Three aspects, i.e., the total environmental impact, the impact during the manufacturing process, and the impact during the use/waste disposal process were analyzed individually as shown in Table 4. All characterization factors of LCA are expressed in units of an equivalent reference substance in the columns of “Unit” in Table 4. The comparison results are presented in the columns of “Reduc.” in Table 4, indicating that, except for the impact of Eutrophication, the environmental impacts in all indices were significantly reduced when the bamboo pipes were applied. Table 4 shows that the total Global warming potential, Acidification, Human health-cancer, Human health-noncancer, Human health criteria air pollutants, Eutrophication, Ecotoxicity, Smog, Habitat alteration, Water intake and Ozone depletion of the PVC pipe were 6.4, 4.3, 488.8, 314.3, 3.3, 0.7, 14.5, 3.7, 1.1, 7.2 and 1.1 times higher than those of the bamboo winding composite pipe, respectively. Fig. 6 presents the comparison of the total environmental impact between PVC pipe and bamboo pipe. The environmental

Fig. 5. Network of the total environmental impact of bamboo winding composite pipe (“1p” is one functional unit, “Pipe manufacturing” means the CO2 produced during the bamboo pipe manufacturing and “Landfill scenario for pipe” means the CO2 produced during the bamboo pipe use/disposal process.).

8

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

Table 4 A comparison of environmental impact assessment between bamboo and PVC pipes. Total impact

Manufacturing

Use and waste disposal

Impact category

Unit

PVC pipe

Bamboo pipe Reduca (times) PVC pipe

Bamboo pipe Reduca (times) PVC pipe Bamboo pipe Reduca (times)

Global warming Acidification Human health-cancer Human health-noncancer HH criteria air pollutants Eutrophication Ecotoxicity Smog Habitat alteration Water intake Ozone depletion

g CO2 eq Hþ moles eq g C6H6 eq g C7H7 eq microDALYs g N eq g 2,4-D eq g NOx eq T&E count liters g CFC-11 eq

495,339.1 89,138.5 45,149.1 57,508,017.3 28.2 141.7 3,528.0 1,072.9 6.2E-13 6,931.4 0.006

77,481.8 20,548.8 92.4 182,954.4 8.5 194.7 243.5 289.9 5.7E-13 966.6 0.005

65,279.1 16,143.4 50.9 118,027.5 6.5 128.5 193.6 200.5 3.7E-13 966.6 0.0016

a

6.4 4.3 488.8 314.3 3.3 0.7 14.5 3.7 1.1 7.2 1.1

272,308.0 63,922.6 44,720.6 56,880,581.6 22.9 94.2 3,304.5 858.7 1.55E-13 6,242.0 0.0008

4.2 4.0 878.6 481.9 3.5 0.7 17.1 4.3 0.4 6.5 0.55

223,031.1 25,215.8 428.5 627,435.7 5.3 47.4 223.5 214.2 4.65E-13 689.4 0.004

12,202.7 4,405.4 41.5 64,927.0 2.0 66.2 49.9 89.4 2.0E-13 0 0.0035

18.3 5.7 10.3 9.7 2.7 0.7 4.5 2.4 2.4 1.1

Reduc. (times) ¼ Value (PVC)/Value (bamboo).

Fig. 6. A comparison of environmental impact of PVC pipe and bamboo pipe.

impact of PVC pipe is shown as hundred percent, whereas the effect of the bamboo pipe is shown as the percentage of the value of PVC pipe. Since the impacts of the two indices, i.e., Human healthcancer and Human health-noncancer of the bamboo winding composite pipe were too small compared with those of PVC pipes (0.20% and 0.32% in Fig. 6, respectively), they could not be illustrated in the figure. Except for the indices of Eutrophication, other indices, i.e., Global warming potential (15.64%), Acidification (23.05%), Human health criteria air pollutants (30.20%), Ecotoxicity (6.90%), Smog (27.02%), Habitat alteration (91.41%), Water intake (13.95%) and Ozone depletion (91.10%), were all significantly reduced when the bamboo winding composite pipe were applied (Fig. 6). 3.2.3. Impact comparisons of six components of bamboo winding pipe by BEES index The bamboo winding composite pipe was made from six major materials, i.e., bamboo slivers, MUF resin, styrene E, Cotton fibers, walnut husk powder, and bamboo fiber fabric. To exactly evaluate the contribution of each component, environmental impacts of the six raw materials during the manufacturing phase were examined and the results are listed in Table 5. Taking the impact of global warming as an example, the different contributions of the six raw materials plus transportation and electricity to the global warming are presented in Fig. 7. It was shown that among the six raw

materials in one functional unit (84 kg) of the bamboo winding composite pipe, the 24 kg bamboo slivers were the most environmentally friendly raw material, which took 28.57% of the total mass (24 kg out of 84 kg), but only contributed 3.0% of the Global warming index as shown in Fig. 7 and Table 5. Also the 6 kg walnut husk and 3 kg bamboo fiber fabric were environmentally friendly, which took 7.14% and 3.57% of the total mass, but only contributed 1.0% and 0.3% of the Global warming indexes, respectively (Fig. 7 and Table 5). As an organic compound with the chemical formula of C6H5CH ¼ CH2, styrene E is the precursor to polystyrene, which is the fifth largest creator of hazardous waste during its manufacturing process, use and disposal in the US. Usually styrene was produced through the dehydrogenation of ethylbenzene. Considering the accumulative energy used, GHG and environmental influence, polystyrene plays the second highest role, behind aluminum, in damaging environment (Future Centre Trust, 2010, accessed on 05 June 2018). The 7 kg Styrene E was the most unenvironmental-friendly raw material in the bamboo winding composite pipe, which took 8.33% of the total mass, but contributed 32.6% of the Global warming index as shown in Fig. 7 and Table 5. The 41 kg MUF resin in the bamboo winding composite pipe also played an un-favorite role in affecting environment, which undertook 48.81% of the total mass and contributed 28.0% of the Global warming index as shown in Fig. 7 and Table 5. In addition to the

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

9

Table 5 Contribution of different bamboo pipe components on environment impacts. Impact category

Bamboo slivers (24 kg)

MUF resin (41 kg)

Walnut husk (6 kg)

Styrene E (7 kg)

Cotton fiber (3 kg)

Bamboo fiber fabric (3 kg)

Transport Electricity

Global warming Acidification HH cancer HH noncancer HH criteria air pollutants Eutrophication Ecotoxicity Smog Natural resource depletion Habitat alteration Water intake Ozone depletion

3.0% 4.9% 8.5% 8.2% 19.2% 11.7% 4.2% 9.1% 2.7%

28.0% 31.5% 8.2% 3.1% 19.2% 5.6% 43.1% 20.4% 81.2%

1.0% 0.6% 0.1% 0.0% 0.3% 5.1% 0.3% 0.4% 0.0%

32.6% 21.7% 10.2% 3.4% 17.4% 1.1% 3.5% 27.6% 0.0%

14.6% 27.2% 48.2% 52.4% 27.3% 67.2% 30.5% 20.1% 5.8%

0.3% 0.7% 0.2% 0.1% 0.7% 0.1% 0.2% 1.4% 0.3%

7.8% 9.0% 19.5% 28.9% 13.0% 8.9% 14.5% 16.5% 10.0%

12.8% 4.3% 5.1% 4.0% 2.9% 0.3% 3.8% 4.5% 0.0%

3.9% 0.0% 4.0%

0.0% 0.0% 0.0%

0.0% 0.0% 0.0%

0.0% 98.8% 0.0%

57.7% 0.0% 45.7%

0.0% 0.0% 0.0%

38.4% 0.0% 50.1%

0.0% 1.2% 0.3%

The total mass of raw materials was 84 kg.

Fig. 7. Contribution of different bamboo pipe components on global warming.

impact index of Global warming, different raw materials of bamboo winding composite pipe contributing to other environment impact indexes are illustrated in Table 5. 3.3. Eco-indicator 99 (environment burden) method The results of Eco-indicator 99 (the burden on the environment) evaluations are presented in Figs. 8 and 9. Based on the calculation of Eco-indicator 99 using the SimaPro software, the total environmental burdens of PVC pipes (a mass of 84 kg as a functional unit) were 82 Pt as shown in Fig. 8. The environmental burdens of bamboo winding composite pipes (a mas of 84 kg as a functional unit) were 11.4 Pt and are shown in Fig. 9. The comparison of Ecoindicator 99 point (environment burdens) between Figs. 8 and 9 illustrated that the PVC pipe produced much more burdens on environment than that of the bamboo pipe (82 Pt V 11.4 Pt as shown in Figs. 8 and 9), counting 7.19 times higher than that of the bamboo winding composite pipe (Table 6). Fig. 8 shows that the Eco-indicator 99 impact index produced by the manufacturing stage of PVC pipe was 75.3 Pt., while the stage of PVC pipe use/waste disposal process was 5.91 Pt, indicating that the manufacturing process had 12.74 times higher environmental

impact than that of the use/disposal process. As shown in Fig. 9, the Eco-indicator 99 impact index produced by the manufacturing stage of bamboo pipe was 9.29 Pt., while the stage of use/waste disposal process was 2.08 Pt., indicating that the manufacturing process had 4.47 times higher environmental impact than that of the use/disposal process. 3.4. Method of cumulative energy demands By considering the all demand energy flowed into the production and service/disposal system of the water pipe (per functional unit), the cumulative energy demands can be estimated by SimaPro, being used to evaluate energy resource efficiency in the LCA process (Heffels et al., 2014). The cumulative energy demand is one of the most useful parameters in judging the energy efficiency of systems because the energy loss due to the manufacturing, transportation and service/disposal are fully accounted for. The cumulative energy demands (MJ) for PVC and bamboo winding pipes were calculated using SimaPro and are illustrated in Table 6. Table 6 illustrates that the cumulative energy demand of PVC pipe was 6,830 MJ, while only 2,010 MJ for the bamboo winding pipe, which was a reduction of 3.40 times.

10

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

Fig. 8. Network of the normalized environmental burden of PVC pipe (“1p” is one functional unit, “PVC pipe manufacturing” is the burden produced during the pipe manufacturing process and “Waste scenario for PVC pipe” is the burden produced during the pipe use and waste disposal process).

functional unit (84 kg) of the bamboo winding composite pipe, the bamboo slivers, walnut husk and bamboo fiber fabric were the environmentally friendly raw materials, while the Styrene E was the most un-environmental-friendly raw material and MUF resin played an second un-favorite role in affecting environment in the bamboo winding composite pipe as shown in Fig. 7 and Table 5. Is it possible to further reduce the environmental impact by modifying the current raw materials, production or transportation? To address this challenge, the sensitivity analyses (Kiesse et al., 2017) was applied by evaluating alternative approaches during the LCA process of bamboo pipes. Three alternative approaches were tested through the sensitivity analyses: Option 1: Styrene E is reduced by 10%, and the total weight per functional unit remained unchanged by increasing the same amount of bamboo slivers; Option 2: Styrene E is reduced by 10% and MUF resin reduced by 10%, and the total weight remained unchanged by increasing the same amount of bamboo slivers; Option 3: The transportation distance between bamboo sliver mill to pipe manufacturer is reduced from 500 km to 250 km. Using SimaPro software, the sensitivity analysis results were summarized and are presented in Table 7. The sensitivity analysis results indicated that, when 10% Styrene E and MUF was replaced by bamboo slivers, the BEES index, Ecoindicator 99 point and cumulative energy demands, were reduced by 4.65, 3.51 and 5.47%, respectively, as shown in Table 7. Table 7 also shows that, if the transportation distance between bamboo sliver mill to pipe manufacturer reduced from 500 km to 250 km, the BEES index, Eco-indicator 99 point and cumulative energy demands were reduced by 3.35, 3.51 and 1.99%, respectively.

4. Conclusions Using the SimaPro software, the life-cycle assessments (LCA) of PVC and bamboo winding composite pipes were compared by three LCA methods, namely, the BEES index, Eco-indicator 99 point and cumulative energy demands. The results and conclusions were summarized as follows:

Fig. 9. Network of the normalized environmental burden of bamboo pipe (“1p” is one functional unit, “Pipe manufacturing” is the burden produced during the pipe manufacturing process and “Landfill scenario for pipe” is the burden produced during the pipe use and waste disposal process).

3.5. Sensitivity analysis The results and discussion in previous sub-sections indicated that using bamboo winding composite pipes instead of PVC pipes could significantly reduce the environmental impact. Among the six components of bamboo wind pipe, it was shown that, in one

 The BEES index evaluation results demonstrated that, when the bamboo winding composite pipes were used to replace PVC pipes for the pipe system, except for the Eutrophication index, all major environmental impact indices were significantly reduced by 1.1e488.8 times as shown in Table 4.  The Eco-indicator 99 point evaluation indicated that the total environmental burdens were reduced by 7.19 times when using the bamboo pipe to replace the PVC pipe.  The cumulative energy demands were reduced by 3.40 times when using the bamboo pipe to replace the PVC pipe.  The comparison of the LCA stages (bamboo pipe production vs. disposal/degradation) revealed that the eq.CO2 index (BEES) for the production stage of the bamboo pipe was 5.35 times of that of the stage of waste pipe disposal/degradation.  The LCA analyses of the six raw materials for the bamboo winding pipe (per functional unit), i.e., 24 kg bamboo slivers, 41 kg MUF resin, 6 kg filler (powder of walnut husk), 7 kg Styrene E, 3 kg cotton textile and 3 kg bamboo fiber fabric,

Table 6 A comparison of Eco-indicator 99 point (Pt) and cumulative energy demands (MJ) between bamboo and PVC pipes.

PVC pipe Bamboo pipe

Eco-indicator 99 point (Pt)

Reduction (times)

Cumulative energy demands (MJ)

Reduction (times)

82 11.4

7.19

6,830 2,010

3.40

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

11

Table 7 Sensitivity analysis results. Impact category

Unit

Bamboo pipe

Option 1

Redu.a (%)

Option 2

Redu.a (%)

Option 3

Redu.a (%)

BEES index Eco-indicator 99 Cumulative energy demands

g-CO2 eq. Pt MJ

77,500 11.4 2,010

75,400 11.1 1,950

2.71 2.63 2.99

73,900 11 1,900

4.65 3.51 5.47

74,900 11 1,970

3.35 3.51 1.99

a Redu. ¼ (original vale-option value)/original value  100; Option 1 ¼ Styrene E reduced by 10%; Option 2 ¼ Both Styrene E and MUF reduced by 10%; Option 3 ¼ The transportation distance between bamboo sliver mill to pipe manufacturer reduced from 500 km to 250 km.

illustrated that the BEES indexes of 41 kg UF resin, 7 kg Styrene E and 3 kg cotton textile were 1.83  104, 2.13  104 and 9.51  103 eq.CO2, respectively (Fig. 5), while the impacts of other raw materials, namely, bamboo slivers, walnut shell powder and bamboo fiber fabric were very small and could be ignored. Therefore, the environment impact of bamboo winding composite pipe can be further reduced if the amount of the MUF resin, Styrene E and cotton textile were reduced.  The sensitivity analysis results illustrated that, when 10% Styrene E and MUF was replaced by bamboo slivers, the environmental impacts can be reduced by 3.51e5.47%.  Based on the sensitivity analysis results, the bamboo winding composite pipe producer could optimize the raw material components of the bamboo pipe to further alleviate environmental impact without compromising the mechanical properties of pipes. Acknowledgements The authors gratefully acknowledge financial support from National 13th Five-year “National Key Research & Development Program of China” (2016YFD0600906), Zhejiang Xinzhou Bamboobased Composites Technology Co., Ltd, China, and the University of North Texas, Texas, USA. References Akhtar, S., Reza, B., Hewage, K., Shahriar, A., Zargar, A., Sadiq, R., 2015. Life cycle sustainability assessment (LCSA) for selection of sewer pipe materials. Clean Technol. Environ. Policy 17, 973e992. https://doi.org/10.1007/s10098-0140849-x. Asadi, S., Babaizadeh, H., Foster, N., Broun, R., 2016. Environmental and economic life cycle assessment of PEX and copper plumbing systems: a case study. J. Clean. Prod. 137, 1228e1236. https://doi.org/10.1016/j.jclepro.2016.08.006. Batouli, S.M., Zhu, Y., Nar, M., D'Souza, N.A., 2014. Environmental performance of kenaf-fiber reinforced polyurethane: a life cycle assessment approach. J. Clean. Prod. 66, 164e173. https://doi.org/10.1016/j.jclepro.2013.11.064. Dennison, F.J., Azapagic, A., Clift, R., Colbourne, J.S., 1999. Life cycle assessment: comparing strategic options for the mains infrastructuredPart I. Water Sci. Technol. 39, 315e319. https://doi.org/10.1016/S0273-1223(99)80002-X. Erses Yay, A.S., 2015. Application of life cycle assessment (LCA) for municipal solid waste management: a case study of Sakarya. J. Clean. Prod. 94, 284e293. https://doi.org/10.1016/j.jclepro.2015.01.089. Faria, H., Guedes, R.M., 2010. Long-term behavior of GFRP pipes: reducing the prediction test duration. Polym. Test. 29, 337e345. https://doi.org/10.1016/ j.polymertesting.2009.12.008. Friedrich, E., Pillay, S., Buckley, C.A., 2007. The use of LCA in the water industry and the case for an environmental performance indicator. Water S.A. 33, 443e451. hdl.handle.net/10520/EJC116465. Future Centre Trust, 2010. The Dangers of Polystyrene. Business Barbados, July 6, 2010. Green Business, Trending. businessbarbados.com/trending/greenbusiness/the-dangers-of-polystyrene/. (Accessed 5 June 2018). Goedkoop, M., Spriensma, R., van Volkshuisvesting, M., en Milieubeheer, R.O., Communicatie, C.D., 1999. The Eco-Indicator 99: A Damage Oriented Method for Life Cycle Impact Assessment, vol 1999. Ministerie van Volkshuisvesting, Ruimtleijke Ordening en Milieubeheer. ci.nii.ac.jp/naid/10014712580/. Hajibabaei, M., Nazif, S., Tavanaei Sereshgi, F., 2018. Life cycle assessment of pipes and piping process in drinking water distribution networks to reduce environmental impact. Sustain. Cities Soc. 43, 538e549. https://doi.org/10.1016/ j.scs.2018.09.014. Halfawy, M., Dridi, L., Baker, S., 2008. Integrated decision support system for optimal renewal planning of sewer networks. J. Comput. Civ. Eng. 22, 360e372. https://doi.org/10.1061/(ASCE)0887-3801(2008)22:6(360). Heffels, T., McKenna, R., Fichtner, W., 2014. An ecological and economic assessment

of absorption-enhanced-reforming (AER) biomass gasification. Energy Convers. Manag. 77, 535e544. https://doi.org/10.1016/j.enconman.2013.09.007. Herrmann, I.T., Moltesen, A., 2015. Does it matter which Life Cycle Assessment (LCA) tool you choose? - a comparative assessment of SimaPro and GaBi. J. Clean. Prod. 86, 163e169. https://doi.org/10.1016/j.jclepro.2014.08.004. Herstein, L., Filion, Y., 2011. Life-cycle assessment of common water main materials in water distribution networks. J. Hydroinf. 13, 346e357. https://doi.org/ 10.2166/hydro.2010.127. Ilyas, R.A., Sapuan, S.M., Ishak, M.R., 2018a. Isolation and characterization of nanocrystalline cellulose from sugar palm fibres (Arenga Pinnata). Carbohydr. Polym. 181, 1038e1051. https://doi.org/10.1016/j.carbpol.2017.11.045. Ilyas, R.A., Sapuan, S.M., Ishak, M.R., Zainudin, E.S., 2018b. Development and characterization of sugar palm nanocrystalline cellulose reinforced sugar palm starch bionanocomposites. Carbohydr. Polym. 202, 186e202. https://doi.org/ 10.1016/j.carbpol.2018.09.002. Ilyas, R.A., Sapuan, S.M., Ishak, M.R., Zainudin, E.S., 2019. Sugar palm nanofibrillated cellulose (Arenga pinnata (Wurmb.)Merr): effect of cycles on their yield, physicchemical, morphological and thermal behavior. Int. J. Biol. Macromol. 123, 379e388. https://doi.org/10.1016/j.ijbiomac.2018.11.124. ISO 14040, 2006. Environmental Management-Life Cycle Assessment Principles and Framework. British Standards Institution, London, UK. ISO 14044, I, 2006. 14044: Environmental Management-Life Cycle Assessment Requirements and Guidelines. International Organization for Standardization. https://doi.org/10.1007/s11367-011-0297-3. Khanna, V., Bakshi, B.R., 2009. Carbon nanofiber polymer composites: evaluation of life cycle energy use. Environ. Sci. Technol. 43, 2078e2084. https://doi.org/ 10.1021/es802101x. Kiesse, T.S., Ventura, A., van der Werf, H.M.G., Cazacliu, B., Idir, R., Andrianandraina, 2017. Introducing economic actors and their possibilities for action in LCA using sensitivity analysis: application to hemp-based insulation products for building applications. J. Clean. Prod. 142, 3905e3916. https://doi.org/10.1016/ j.jclepro.2016.10.069. Korol, J., Burchart-Korol, D., Pichlak, M., 2016. Expansion of environmental impact assessment for eco-efficiency evaluation of biocomposites for industrial application. J. Clean. Prod. 113, 144e152. https://doi.org/10.1016/j.jclepro.2015.11.101. Lippiatt, B.C., 2007. BEESRG 4.0: Building for Environmental and Economic Sustainability Technical Manual and User Guide, Standards. globalspec.com/std/ 1084680/BEES%204.0. Lippiatt, B.C., Boyles, A.S., 2001. Using BEES to select cost-effective green products. The International Journal of Life Cycle Assessment 6, 76e80. https://doi.org/ 10.1007/BF02977841. Loss, A., Toniolo, S., Mazzi, A., Manzardo, A., Scipioni, A., 2018. LCA comparison of traditional open cut and pipe bursting systems for relining water pipelines. Resour. Conserv. Recycl. 128, 458e469. https://doi.org/10.1016/ j.resconrec.2016.08.001. Mirza, S., 2007. Danger Ahead: the Coming Collapse of Canada's Municipal Infrastructure. Federation of Canadian Municipalities, Ottawa, Canada. www. worldcat.org/title/danger-ahead-the-coming-collapse-of-canadas-municipalinfrastructure/oclc/759007537. , N., de la Fuente, A., Pujadas, P., Gabarrell, X., Rieradevall, J., Petit-Boix, A., Roige Josa, A., 2016. Integrated structural analysis and life cycle assessment of equivalent trench-pipe systems for sewerage. Water Resour. Manag. 30, 1117e1130. https://doi.org/10.1007/s11269-015-1214-5. PlasticsEurope, 2018. Plastics, Sustainability and Society. www.plasticseurope.org/ en. (Accessed 25 July 2018). ez, R.P., 2005. Estimate of Energy Recio, J.M.B., Guerrero, P.J., Ageitos, M.G., Narva Consumption and CO2emission Associated with the Production, Use and Final Disposal of PVC HDPE, PP, Ductile Iron and Concrete Pipes. Universitat cnica de Catalunya, Barcelona, Spain. Polite Turner, H., 2007. The Benefits of Polyethylene vs: Traditional Materials in Water and Wastewater Pipe Applications. Underground Infrastructure Management, Cambridge, the United Kingdom. www.pepipe.org/uploads/pdfs/Just another drop in the bucket.Pdf. Vahidi, E., Jin, E., Das, M., Singh, M., Zhao, F., 2016. Environmental life cycle analysis of pipe materials for sewer systems. Sustain. Cities Soc. 27, 167e174. https:// doi.org/10.1016/j.scs.2016.06.028. Venkatesh, G., Hammervold, J., Brattebø, H., 2009. Combined MFA-LCA for analysis of wastewater. J. Ind. Ecol. 13, 532e549. https://doi.org/10.1111/j.15309290.2009.00143.x. €nder, J.G., van der Velden, N.M., van der Lugt, P., 2014. Carbon sequestration Vogtla in LCA, a proposal for a new approach based on the global carbon cycle; cases on wood and on bamboo. Int. J. Life Cycle Assess. 19, 13e23. https://doi.org/

12

S.Q. Shi et al. / Journal of Cleaner Production 240 (2019) 118172

10.1007/s11367-013-0629-6. Wilson, B.J., 2009. CORRIM: Phase II Final Report, Module H. Resins: A Life-Cycle Inventory of Manufacturing Resins. Used in the Wood Composites Industry. January 2009. www.corrim.org/pubs/reports/2010/phase2/Module_H.pdf. Wu, W., Xia, C., Cai, L., Garcia, A.C., Shi, S.Q., 2018. Development of natural fiberreinforced composite with comparable mechanical properties and reduced energy consumption and environmental impacts for replacing automotive glass-fiber sheet molding compound. J. Clean. Prod. 184, 92e100. https://

doi.org/10.1016/j.jclepro.2018.02.257. Zhao, J., Yao, T., 2012. Calculation of ring-bending stiffness of buried round plastic pipeline. J. Hohai Univ. (Nat. Sci.) 40 (4), 393e396. https://doi.org/10.3876/ j.issn.1000-19802012.04.006. Zhou, C., Shi, S.Q., Chen, Z., Cai, L., Smith, L., 2018. Comparative environmental life cycle assessment of fiber reinforced cement panel between kenaf and glass fibers. J. Clean. Prod. 200, 196e204. https://doi.org/10.1016/ j.jclepro.2018.07.200.