Guideline for Calculating CO2 Emission from Ready Mixed Concrete Production and Its Case Studies

Piti Sukontasukkul Associate Professor, Civil Engineering, KMUTNB

Member of ACF-Sustainability Forum

‘Sustainability in Concrete Technology and Construction’ Petra Christian University, 18 September 2013

Environmental Issues in Concrete Construction Sector

CO2 Emission (use of fossil fuels)

Manufacturing of cement and concrete

Construction activities

Transportation

Natural resources depletion

Wastes generation

Soil and water contamination

Global Warming

Over the last 400,000 years, the atmospheric CO2 concentrations is fluctuated up and down with the upper and lower limit about 300 and 200 ppm, respectively. (from the ice core data).

Today, CO2 concentrations worldwide is average about 380 ppm.

‘Sustainability in Concrete Technology and Construction’ Petra Christian University, 18 September 2013

Previous Actions to Environmental Issues

The National Trust (1895), UK

•A non-profit or charitable organizations created to preserve “the benefit of the Nation of lands and tenements of beauty or historic interest and, as regards lands, for the preservation of their natural aspect, features and animal and plant life……”

The Limits to Growth (1971):

A book with a purpose to explore how exponential

growth interacts with finite resources.

UN Conference on Human Environment (1972)

•A Declaration containing 26 principles concerning the environment and development.

•“……23. Each nation must establish its own standards 24. There must be cooperation on international issues 25. International organizations should help to improve the environment…..”

‘Sustainability in Concrete Technology and Construction’ Petra Christian University, 18 September 2013

Previous Actions to Environmental Issues

Brundtland Report (1987)

•A report mandated ‘reexamine, create action plans, promote international corporation and rise level on understanding on environmental issues.

Earth Summit: UN Conference on Environment and Development (1992)

•..Alternative sources of energy to replace the use of fossil fuels which are linked to global climate change…..

Kyoto Protocol (1997)

•A protocol to the UN Framework Convention on Climate Change (UNFCCC or FCCC) that set binding obligations on the industrialized countries to reduce their emissions of greenhouse gases.

IPCC Assessment Reports (90, 95, 01, 07)

•"most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations."

‘Sustainability in Concrete Technology and Construction’ Petra Christian University, 18 September 2013

International and National Standards

Japan

• JSCE Environmental Performance Verification for Concrete Structures

FIB

•FIB-TG 3.6 Guideline for Environmental Design of Concrete Structures

•FIB-TG. 3.8 Guideline of Green Concrete Structures

ISO

• ISO/TC 71/SC 8 ISO/FDIs 13315-1:2011 (E) Environmental management for concrete and concrete structures Part 1: General principle

• ISO/TC 71/SC 8 ISO/CD 13315-2 Part 2: system boundary and inventory data

USA

•LEEDS for Green Building*

TCA

•Guideline for Calculation CO2 Emission in Concrete Production*

‘Sustainability in Concrete Technology and Construction’ Petra Christian University, 18 September 2013

TCA Manual for calculating CO2 emission from concrete production (2011)

TCA recognizes the importance of concrete sustainability. TCA-TG4 is established in 2010.

Launch in 2011, the manual provides a simple and easy to use tool for engineers to calculate CO2 emission from the production process of concrete used in their construction site.

Employing similar approach to ISO 13315 using LCI and LCIA to

calculate CO2 from concrete production process.

The manual is applied for both local (on-site) and ready mixed concrete productions.

Scope of the manual

Determine CO2 emission from the production process of concrete. Calculation extent to cover 3 main parts: Materials Manufacturing, Concrete Production Process, and Transportation. Production processes include: hand mixing, small (drum) mixer, and ready-mixing process. Transportation include ready mixed truck.

Impact Category: Global Warming

Impact Indicator: CO2 emission

Functional unit: kg of CO2 per 1 m3 of concrete.

System Boundary : Concrete Production

System Boundary

Concrete Mixing Process

Concrete

Raw Materials

tran

Energies : Fuel, Electricity

tran

Construction Site or

Precast Factory

Cement content

Aggregate content

Admixtures

Supplementary materials

CO2

Transportation

Concrete Mix

Selection

Inventory data: Raw Materials

a Anna Korre and Sevket Durucan, EVA025-Final Report: Aggregates Industry Life Cycle Assessment

Model: Modeling Tools and Case Studies, 2007[11] b MTEC, NSTDA c Tananan Panussupsuk, M.Eng. Thesis, KMUTNB

Materials Unit (*) CO2 emission

(kg-CO2/*)

Portland Cement Ton 847

River Sand Ton 3.920

Limestone a Ton 2.43-4.14

Rebar b Ton 1760

Masonry Brick c Sq. m 3.803

Masonry Mortar (1:2.5) c Sq. m 6.728

Plastering Mortar (1:3) c Sq. m 10.305

Inventory data: Production type

Mixers Type Energy (J/m3)

Electricity (kW/m3)

Unit CO2Emission (kg-CO2/unit)

0.1 m3 Typea 1.68x107 - m3 2.68

0.2m3 Type 1.25x107 - m3 2.01

Ready-mixed Type d - 2.15 m3 1.23

d Insee Concrete, co., ltd. (Thailand)

Inventory data: Transportation

Type

Capacity

Fuel Consumption

EF CO2Emission

unit kg-CO2/

litre

kg-CO2/

km

kg-CO2/

(km.unit)

Ready-mixed

Trucka 5 m3 2.7 km/l 0.54

km/

(l.m3) 2.58 0.96 0.19

Ready-mixed

Truckb 5 m3 2.9 km/l 0.58

km/

(l.m3) 2.58 0.89 0.18

Ready-mixed

Truck

(Idling mode)

5 m3 6 l/trip 1.20 l/(trip.m3) 2.58 15.48

kg-CO2/trip

3.10

kg-

CO2/trip.m3

a Travel within Bangkok and vicinity (Ref. CPAC, Thailand 2012) b Travel outside Bangkok and vicinity (Ref. CPAC, Thailand 2012) c Allowable truck load capacity

Additional Inventory: Transportation

Vehicle Type Unit (*) CO2 emission

(kg-CO2 /*)

10 Wheel Truck (16 t)A km.ton 0.053

Pick-up Truck (7t)A km.ton 0.14

18 Wheeler A km.ton 0.014

8t Crane Truck (6w)C -Driving km. 0.683

25t Crane Truck (4w)C -Driving km. 1.206

25t Crane Truck (10w)C -Driving km. 0.992

8t Crane Truck (6w)C - Operating minute 0.629

25t Crane Truck (4w)C- Operating minute 0.198

25t Crane Truck (10w)C - Operating minute 1.563

Aอ้างอิงจาก MTEC: 2554[2] Bอ้างอิงจาก บริษัทผลิตภณัฑ์และวัสดุก่อสร้าง (CPAC, Thailand 2012) Cอ้างอิงจาก ข้อมูลท่ีท าการจัดเก็บ

Inventory data: Energies

Energy Type Specific Heat or Energy per Litre Spec. CO2 Emission

Factor

btu/L Kcal/L kJ/L kWh/L kg-CO2/kWh kg-CO2/l

High speed

diesel

36722 9,277.45 38,743.7 10.76 0.24 2.58

Natural gas 35.32 8.92 37.26 0.0104 0.23 0.00238

Electricity - - - - 0.575 -

Case Study 1: CO2 Emission from Ready Mixed

Concrete Production and Transportation of Single House Real-

Estate Project

General Information

Housing project

• Project Name: Perfect Place, Property Perfect Co., Ltd.

• Number of Houses: 1119 Units (Fig. 1)

• Area: 397000 sq.m

• Construction Systems:

• Cast-in-place concrete structure 384 units

• Prefabricated concrete structure 735 units (not included in this study)

Concrete

• Concrete strength: 24 MPa (28 days)

• Mix Proportions: 389:1024:775:200 kg. (C:CA:FA:W)

Project Plan

Case Study

Const.

System House Type

Number Quantity (m3)

Unit per house Total

Cast-in-place A 1 28.50 28.5

B 19 32.00 608

C 238 18.60 4426.8

D 1 16.60 16.6

E 30 15.50 465

F 7 32.00 224

G 84 20.60 1730.4

H 4 20.60 82.4

Sub Total 384 184.40 70809

Results: Concrete Production

Materials Quantity EF Emission

kg/m3-

concrete kg-CO2/t (kg-CO2)

Cement 389 847 329.5

Coarse

Aggregate 1024 4.14 4.2

Fine Aggregate 775 3.92 3.0

Emission (kg-CO2 per m3-concrete) 336.7

Total Quantity of concrete (m3) 70,809.6

Total Emission from Concrete

Production (t) 23,841.6

Total Quantity

of concrete

(m3)

Emission

Factor Mixing

(kg-CO2/m3)

Total Emission

from Concrete

Production (t)

70809.6 1.2 87.10

98.77%

0.32% 0.91%

Material

Production

Transportation

Total Quantity of Concrete

Number of trip

Distance (km)

Total Distance

EF for Ready mixed Truck

CO2 Emission (t)

70809.6 14161.92 12 169943.04 0.96 163.14 70809.6 14161.92 6 kg/trip 84.97

Case Study 2: CO2 Emission from Construction

of a Single House using Prefabricating System

General Information

Total area 112.65 sq.m 1st floor 65.75 sq.m 2nd floor 46.91 sq.m

Scope and Category

• Impact Categories: CO2 Emission from Energy Usage involved in Construction Process

• Functional Unit: kg of CO2 Emission per Unit Work

• Scope: – Determining CO2 emission based on energy usage

involved in construction of super-structure of a single house using prefabrication system. Substructures are excluded from the study.

– Consider only concrete work start from mixing, delivery, casting, delivering and installing.

Construction Process Prefabrication Factory

Presentation for W.R.GRACE Seminar 2013

System Boundary: Prefabrication Factory

Ready mixed concrete

Steel

Installing template

Welding steel

Curing

Wastes

Prefabrication component

Electricity Fuels

CO2

System BoundaryPrecast Concrete

Placing concrete

Storage

Trans.

Trans.

Trans.

Trans.

Additional Inventory: Prefabrication Equipments

Equipments Energy Type Unit(*) CO2

emission (kg-CO2/*)

Rebar Cutter Electricity Time 0.061 Rebar Bender Electricity Time 0.0003

Concrete Vibrator Electricity m3 of concrete

0.0362

Moving Crane* Electricity

m3 of concrete

0.0414

*ได้จากการค านวณจากข้อมูลท่ีจัดเก็บ

(ระยะเคลื่อนท่ีของเครนไฟฟ้าในการขนส่งเฉลี่ยท่ี 30 เมตร) Eอ้างอิงจากสมาคมคอนกรีตแห่งประเทศไทย [3]

Construction Process Installation Process

System Boundary: Installation Process

Installing

Welding components Wastes

Concrete structure

Electricity Fuels

CO2

System BoundaryBeam , Slab , Wall

Finishing

Trans.

Prefabrication component

Trans.

Trans.

Bill of Quantity

Type Component Concrete Quantity (m3) Type Component Concrete Quantity

(m3) 1st Fl. Beam GB21 0.895 2nd Fl Slab S3 1.420

GB22-1 0.312 RC 1.077 GB22-2 0.208 S2 0.660 GB23 0.113 S1A 1.716 GB24 0.336 S4 3.188 GB25 0.320 GB26 0.238 GB27 0.242 GB28 0.281 GB29 0.150 GB30 0.242 GB31 0.499 GB32 0.148

Total 3.984 Total 8.061

1st Fl. Wall W1-2 1.381 2nd Fl. Wall 2W3 0.373 W8 0.789 2W5 0.760 W9-1 0.450 2W4S 1.395 W5 1.025 2W1-1 0.825 W4-2 0.504 2W4 0.583 WB9 0.721 2W8 0.668 WB8 0.152 2W2 1.616 W1-1 0.800 2W10 0.844 W7 0.689 2W11 0.632 W6 0.661 2W1-2 1.331 W2 1.200 2W9 1.585 W3 0.539 2W6S 0.883 W4-1 0.836

Total 9.747 Total 11.495

Prefabricating Process

Category Task EF

kg-CO2/(*) Unit (*)

Quantity kg-CO2

Ready mixed Concrete

Materials Ready mixed Concrete(320 ksc.) 335.86 m3 33.29 11,179.64

Process Mixing and loading 1.23 m3 33.29 40.94

Delivery Delivery (10 km) 0.18 m3.km 33.29 31.91

Casting

Process Placing and Compacting 0.03 m3 33.29 0.51

Stocking 1.71 hr.m3 33.29x3.95 3.75

(average moving distance 30 m and average operating time of 3.95 min/m3)

Total 11,256.75

Delivery and Installation

Floor Task Equipment EF

kg-CO2/(*) Unit (*)

Quantity kg-CO2

All floor Delivery 18 Wheeler (15 km) 0.014 km.t 44.3 117.69

1st floor Installation 4 Wheel Crane Truck (25 ton) -

Operating Mode 0.198 min 264.1 52.3

2nd Floor Installation 4 Wheel Crane Truck (25 ton) -

Operating Mode 0.198 min 259.0 51.3

Total 121.3

Summary

Conclusion

• Based on the three main categories: materials, process, and transportation, it could be seen that the CO2 Emission of a single house concrete construction is mainly fell in the material category.

• Cement is still a major contributor in the CO2 emission from the manufacturing stage to the construction stage.

• This manual is still far from finished and research is needed to be carried out in order to fulfill the gap.