Stabilization Of Diesel Contaminant Soil With Lime And Fly Ash

Admixture

Researched By

Peter G. Nicholson and Pamela R. Tsugawa

Presents By

Mr. Sarun Thanavibulsate

Mr. Thapana Thanatsang

Introduction

Source: Diesel productionTransportationPetroleum storageOther of petroleum product

Hazard: Effect central nervous systemHeadachesAppetite lossWeakness

Lime and Fly Ash

Lime Various forms of lime – Quicklime CaO Modify many engineering properties of soil

- Pozzolanic reaction improve strength and durability

Fly Ash• By product from power plants• Used to Stabilize the soil

- Short term improved the workability, reduction in PI and shrinkage

- Long term improve strength due to pozzolanic reaction

What is pozzalan???

Source of silica or alumina with large surface area

‘Fly Ash’ and certain soil type

Can be hydrated by earth alkali to form cementitious product

‘Pozzolanic reaction’ Lime can speed up

‘pozzolanic reaction’ Encourage cation exchange

Description of Sample Tested

Two groups of sample being tested

- Uncontaminated, original Soil

- Contaminated sample

- untreated

- treated with lime

- treated with Fly Ash

- Treated with both

Diesel concentration in soil after treatment

Diesel conc plotted vs time

Both helps to reduce diesel conc in soil

Diesel stabilization fastest when both lime and fly ash is used

Fly ash- pozzolan Lime- speed up ion

exchange

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

0 7 14 21 28

Time (day)

TPH-

D in

soil

conc

entra

tion

(ppm

)

Lime treated

Fly ash treatd

Lime and f lyash treated

Unconfined soil strength after treatment

The unconfined compression test

Fly ash and lime treated clearly show most increase in strength

Cementation speeds up by– Pozzolan fly ash– Basic lime

0

100

200

300

400

500

600

700

0 7 28

Time, (days)

UC

S, (

kPa)

Uncontaminated

Contaminateduntreat

Fly ash treated

Lime treated

Fly ash and limetreated

Diesel concentration in leachate

Less than 1 ppm of diesel in both untreated and treated leachate

It was not detectible However, sensory observation revealed that:

– No leachate smell from treated sample– Some leachate smell from untreated sample

Conclusion

Lime and fly-ash combination admixture is best at stabilising diesel contaminated soil

Also improve the soil strength the most No addition waste material to land field site Construction possible, land reclamation A very good alternative