Environmental Sustainablility of PVC

Resource Efficient + energy efficient + highly recyclable

Environmental Sustainability of PVC Pipe

Resource Efficiency

PVC saves fossil fuels. Its principal raw material is chlorine derived from common salt which is not a threatened resource.

Energy Efficiency

PVC pipe production consumes less primary energy in the manufacturing process when compared to steel, clay or ductile iron.

Highly Recyclable

Waste generated during pipe extrusion is pulverized and reprocessed and can be repeatedly extruded.

PVC pipe - the specifiers choice

Lifeline for potable water

Potable water reticulation systems and effective wastewater handling systems are vital for the sustainable supply of clean drinking water. It is here that PVC as pipe material provides superior fit for purpose performance. PVC pipes minimize water losses by reducing line breakages. PVC water and sewer pipes are designed to perform without leakages. PVC pipe have a proven service life of up to 100 years. These characteristics save water and reduce cost of maintenance.

Water quality

PVC pipe delivers water as clean and pure as it is found at source. It imparts no taste or odor to the water it transports. It is not a source for the lead associated with metal pipe. PVC does not react with even the most aggressive water. The smooth interior surface is not bio-degradable and is resistant to biofilm build-up, a potential source of water disease such as E.coli.

Water tight joints

Water tight joints prevent the loss of valuable drinking water. PVC sewer pipe reduces leaks and reduce the chances of groundwater contamination. The water tight joints also reduce infiltration of groundwater and thus reduce the volume of water requiring treatment. Lower volume of water requiring treatment reduces operating cost of water treatment plants. Water tight joints also prevent the likelihood that embedment soil will be washed away. Gasketed push together PVC pipe systems are easy to install and can be placed in service quickly.

Corrosion resistance

PVC pipe is not vulnerable to external underground erosion or internal pipe corrosion. This eliminates the need to seek protection methods for corrosion. With PVC long-term durability is not compromised when encasement bags are damaged. PVC pipe is resistant to virtually all chemicals found in domestic and industrial waste water. PVC pipe is highly resistant to erosion or abrasion wear. Because PVC does not corrode it has among the lowest pipe break rates per km, saving precious water resources.

Strength

PVC systems can be designed to handle external loads as high as 75000 kg/m³ .This load represents up to 40 meters of ground cover. PVC pipes are able to handle ground movements by unstable and shifting soils.

Superior flow

PVC is corrosion resistant and this eliminates build-up of corrosion products that reduce hydraulic capacity. The smooth wall minimizes friction and flow resistance. The need for cleaning and maintenance is reduced and operating cost is thus reduced.

Superior strength-to-weight ratio

A lower mass of material is required to manufacture a meter of PVC pipe versus a meter of metal or concrete pipe. This weight advantage is significant. It makes PVC economically competitive on a length by length basis. It conserves resources, lowers transport cost, simplifies and reduces time required for installation. PVC reduces risk of injury to installation crews. Altogether PVC pipes reduce installation costs.

Toughness

PVC pipes can bend or flex when subjected to excessive loads. PVC pipes develop fewer cracks and breaks, thus minimizing leaks and operating costs. Water that leaks into waste water systems through cracks can increase the amount of water that requires treatment. This can drive up operating cost significantly.

Failure statistics of pipes (source DVGW) - Germany year 2003



Environmental sustainability of PVC Pipe

PVC is resource efficient PVC makes highly efficient use of the earth's scarce resources. PVC saves energy and reduces CO2 emissions. PVC pipe takes less energy to produce compared with competing materials. PVC saves fossil fuels. Its principal raw material is chlorine derived from common salt. Salt is not a threatened resource. Underground salt deposits are estimated at 200 billion tons and salt from oceans make up approximately 50 quadrillion tons. The remainder of the molecular weight of PVC comes from hydrocarbon stocks. Ethylene from oil makes up 0.3% of annual oil use.

PVC feedstocks



PVC pipe is energy efficient

PVC pipe is energy efficient; this provides a saving of scarce fossil fuels. PVC Pipe production consumes less primary energy in the manufacturing process than steel, clay, or ductile iron.

DN 250 pipe (according to EN standards)

PVC Clay Duct. iron
Material energy (MJ/kg) 56 10 25
Weight of pipe (kg/m) 5.7 33 40
Energy (MJ/m) 319 330 1000
Oil consumption (kg) 6.9 7.2 21.7
CO emitted (kg) 20.8 21.5 65.2
Assumptions: all energy from petrol. Petrol energy 46MJ/kg. Source ECVM

Carbon dioxide generated in the PVC pipe manufacturing is lower than traditional materials.

CO2 emitted / m of pipe (kg)



PVC is eminently recyclable

PVC is one of the most recycled plastics. PVC can be extruded many times without loss of mechanical properties. Waste generated during pipe extrusion is pulverized and reprocessed.

Key economic factors

Competitive cost

  • Low cost per length of pipe
  • Light weight reduces cost of installation

Durability of PVC pipes

  • Long product lifespan translates into lower lifespan cost
  • It has been shown that PVC easily lasts over 50 years (Novak study in Germany- Potable water pipe installed in 1938 still in good condition)
  • PVC is chemically inert and not sensitive to oxygen or oxidizing agents
  • The "flexibility" or toughness of PVC pipes allows them to withstand ground movement

Smooth and clean surface saves money and reduces environmental impact

  • Lower friction gives higher flow speeds and volumes
  • Lower load on pumping operations
  • Less chance of blockage
  • Glass-like surface makes it difficult for bacteria to lodge and grow

Why PVC pipes?

  • Tried and tested
  • Cost efficient
  • Long lasting
  • Light weight
  • Easy to install and maintain
  • Immune to corrosion
  • No rust and scale development
  • Recyclable
  • Good sealing system stops leakage

CONSERVATION OF ENERGY

Conservation of energy is one of the critical issues facing the world and especially Southern Africa. Most of the world's energy is produced from fossil fuels - oil, coal and gas, and the following comparison of the energy consumed in manufacturing various pipeline materials emphasises the advantages of PVC.

Energy Required to Produce 100km of 110mm Class 16

Water Pipe Plus Fittings
Pipeline Material Energy Requirement
(Tons of oil equivalent)
Energy Requirement
(GWh)
PVC-O 331 3.85
PVC-M 468 5.44
PVC-U 653 7.59
Steel Pipe 1 500 17.44
Cast Iron Pipe 1 970 22.91

THE ENVIRONMENT

Society is increasingly concerned with the need to sustain economic development without depleting natural
resources or harming the environment. In every aspect of life, focus must be given to minimizing the environmental impact while, at the same time, increasing economic and social value.

Environmental concerns relate directly to energy conservation and the more effective use of natural resources. PVC comprises raw materials sourced locally from approximately 44% fossil hydrocarbons (oil and coal) and 56% salt. At the end of their life PVC pipes can be collected, recycled and used in other products.