IMPROVE SAFETY IN DEWATERED

SLUDGE DRYING WHILE REDUCING

YOUR ENERGY BILL

Evaporis™LT

BIOSOLIDSLOW TEMPERATURE

SLUDGE DRYING SYSTEM

P-PPT-B-009-EN-1107

BIOSOLIDESBIOSOLIDS

2

2

CONTENTS

• Evaporis™ LT on the dryness scale

• Evaporis™ LT Workshop

• Evaporis™ LT: the uses

• A technology in partnership with STC

• Key Points

• Operating Principles

• Evaporis™ LT Advantages

• Case Study: Saint Marcellin, FRANCE

Evaporis™

LT

BIOSOLIDESBIOSOLIDS

3

3

Evaporis LT ON THE DRYNESS SCALE

Evaporis™

LT

0,4 %Dryness

4 – 6 %20 – 45 %

60 – 90 %

Process Thickening Dehydration Drying

Sludge Volume / Extracted Water Volume

Range Name Drainis™ Dehydris™ Evaporis™

Process Name Drainis™ Turbo

Dehydris™ Osmo

Dehydris™ Lime

Dehydris™ Twist

Evaporis™ LT

Evaporis™ LE

BIOSOLIDESBIOSOLIDS

4

4

Evaporis LT WORKSHOP

Evaporis™

LT

5

Evaporis LT – THE USES

Uses Uses Uses Uses

Thermal Low-temperature belt dryer

Cement-making Incineration orCo-incineration

(Household waste incinerator, thermal power plant, etc.)

Composting Agricultural use

BIOSOLIDESBIOSOLIDS

6

6

STC: AN RECOGNIZED LEADER IN SLUDGE DRYING

Evaporis™ LT uses the dryer of the Spanish company STC (Sistemas de Transferencia de Calor) located in Castellon, specializing in the thermal drying of sludge at low temperatures. A partnership contract has been signed between STC and Degrémont.

The STC company is 100% owned by AGBAR, which is part of the Suez Environnement Group.

The STC company, founded in the 1980s, has already carried out many projects in this field (Besós, Alicante and Guadalhorce in Spain and Dublin South in Ireland).

Evaporis™

LT

BIOSOLIDESBIOSOLIDS

7

7

FIELD OF APPLICATION: • Urban Wastewater sludge:

– Primary or physical-chemical, fresh– Biological with or without tertiary sludge– Mixed fresh or digested

• Industrial wastewater sludge: biological sludge

MINIMUM DRYNESS:

• Dryness of the dehydrated sludge to be dried> 25% dry matter

KEY POINTS

Evaporis™

LT

8

OPERATING PRINCIPLES:THE STC DRYER (1/3)

Sludge extrusion into strands

Transport on two dryer belts

Recovery of dried sludge

Condensatesextraction

Intake of dewatered sludge1

2

3

4

5

9

Drying module 1

Drying module 2

OPERATING PRINCIPLES:THE STC DRYER (2/3)

• Dewatered sludge strands deposit on the upper belt

• Extraction of dried sludge

Module O

Drying modules

Module R

Discharge of sludge in process of drying from upper belt to the lower one

The sludge is then transported along on the two dryer belts.

10

OPERATING PRINCIPLES:THE STC DRYER (3/3)

Label1

Main fans Condenser fansDESCRIPTION OF THE AIR LOOP:

Hot air loaded with humidity.

Most of this hot and humid air is sent to heat exchangers = heating to 80°C

The other part of the hot and humid air goes through the condensation exchangers (extraction of water from the hot air) = Air that is less humid and colder.

Mixing of 2 air masses = overall this new air is less humid, but is hot. This hot and less humid air then goes from

the bottom to the top of the dryer through the 2 belts supporting the bed of sludge strands. In passing, this hot air takes on humidity = new cycle

1

32

4

5

1

2

3

4

5

BIOSOLIDESBIOSOLIDS

11

11

ENVIRONMENT:• Limits greenhouse gas emissions,

• Increased control of odor problem due to the closed-loop air circulation system, and the low-temperature dryer.

SAVINGS:•Decrease in energy consumption due to the

recovery of low-caloric heat used in the process (cogeneration, heating and air conditioning systems, residual energy, etc.),

•All-electric function option (heat pump) to make the most relevant economic choices depending on the requirements,

• Initial investment depending on the client’s needs at a given time.

Evaporis™

LT

Evaporis LT ADVANTAGES (1/2)

BIOSOLIDESBIOSOLIDS

12

12

EASY OPERATION:•Quick start-up and automated process,

• Low maintenance,

• Easy access to all equipment.

SAFETY:•Dryers not concerned by ATEX regulations,

•Dust-free,

• Low operating temperature of dryer,

•Degrémont’s experience with storage (short storage in silos and longer storage in bins).

Evaporis™

LT

Evaporis LT ADVANTAGES (2/2)

13

CASE STUDY: SAINT MARCELLIN, FRANCE

CONTEXT: • Construction of a 50,000 PE WWTP

• Client: Syndicat Intercommunal à Vocations Multiples (SYVOM) of Saint Marcellin

• Commissioning of the plant: 2012

SITUATION:The need for a new plant was due to two points: keeping up with changes to local regulations (new discharge standards) and the handling of effluents from neighboring municipalities.

PROBL

DESIGN:• Sludge treatment line:Thickening, digestion, dehydration and thermal drying with double-fuelwood and biogas burner

• Dryer capacity: 560 Kg of water evaporated per hour

• Use of energy burner using wood and biogas produced by sludge digestion

14

CASE STUDY:SAINT MARCELLIN, FRANCE

STC Dryer