Evaporis LT - Low temperature sludge drying system
3 likes1,936 views
This document describes the EvaporisTM LT low temperature biosolids drying system. It discusses how the system works, its advantages over other drying methods, and provides a case study of its implementation in Saint Marcellin, France. The key points are that the EvaporisTM LT system uses low temperature drying belts to dry dewatered sludge into a dry, stable end product while reducing energy usage and greenhouse gas emissions compared to other drying technologies.
Evaporis LT - Low temperature sludge drying system
- 1. Evaporis™ LT LOW TEMPERATURE BIOSOLIDS SLUDGE DRYING SYSTEM IMPROVE SAFETY IN DEWATERED P-PPT-B-009-EN-1107 SLUDGE DRYING WHILE REDUCING YOUR ENERGY BILL
- 2. BIOSOLIDS BIOSOLIDES CONTENTS Evaporis™ LT • 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 2 2
- 3. BIOSOLIDS BIOSOLIDES Evaporis LT ON THE DRYNESS SCALE Evaporis™ LT 60 – 90 % 20 – 45 % 4–6% 0,4 % Dryness Process Thickening Dehydration Drying Sludge Volume / Extracted Water Volume Range Name Drainis™ Dehydris™ Evaporis™ Dehydris™ Osmo Evaporis™ LT Process Name Drainis™ Turbo Dehydris™ Lime Evaporis™ LE Dehydris™ Twist 3 3
- 4. BIOSOLIDS BIOSOLIDES Evaporis LT WORKSHOP Evaporis™ LT 4 4
- 5. Evaporis LT – THE USES Thermal Low-temperature belt dryer Uses Uses Uses Uses Cement-making Incineration or Composting Agricultural use Co-incineration (Household waste incinerator, thermal power plant, etc.) 5
- 6. BIOSOLIDS BIOSOLIDES STC: AN RECOGNIZED LEADER IN SLUDGE DRYING Evaporis™ LT 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). 6 6
- 7. BIOSOLIDS BIOSOLIDES KEY POINTS Evaporis™ LT 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 7 7
- 8. OPERATING PRINCIPLES: THE STC DRYER (1/3) Intake of dewatered 1 sludge Transport on 3 two dryer belts 2 Sludge extrusion Condensates into strands 4 extraction 5 Recovery of dried sludge 8
- 9. OPERATING PRINCIPLES: THE STC DRYER (2/3) Module O The sludge is then transported along on the two dryer belts. Drying modules • Dewatered sludge strands deposit on the upper belt Module R • Extraction of dried sludge Discharge of Drying module 1 sludge in process of drying from upper belt to the lower one Drying module 2 9
- 10. OPERATING PRINCIPLES: THE STC DRYER (3/3) Main fans Condenser fans DESCRIPTION OF THE AIR LOOP: Label1 4 1 Hot air loaded with humidity. 2 3 2 Most of this hot and humid air is sent to heat exchangers = heating to 80°C 1 3 The other part of the hot and humid air goes through the condensation exchangers 5 (extraction of water from the hot air) = Air that is less humid and colder. 4 Mixing of 2 air masses = overall this new air is less humid, but is hot. This hot and less humid air then goes from 5 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 10
- 11. BIOSOLIDS BIOSOLIDES Evaporis LT ADVANTAGES (1/2) Evaporis™ LT 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. 11 11
- 12. BIOSOLIDS BIOSOLIDES Evaporis LT ADVANTAGES (2/2) Evaporis™ LT 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). 12 12
- 13. CASE STUDY: SAINT MARCELLIN, FRANCE CONTEXT: DESIGN: • Construction of a 50,000 PE WWTP • Sludge treatment line: • Client: Syndicat Intercommunal à Vocations Thickening, digestion, dehydration and Multiples (SYVOM) of Saint Marcellin thermal drying with double-fuel • Commissioning of the plant: 2012 wood and biogas burner • Dryer capacity: 560 Kg of water SITUATION: evaporated per hour The need for a new plant was due to two points: keeping up with changes to local • Use of energy burner using wood and regulations (new discharge standards) and biogas produced by sludge digestion the handling of effluents from neighboring municipalities. PROBL 13
- 14. CASE STUDY: SAINT MARCELLIN, FRANCE STC Dryer 14