IN PLANT TRAINING REPORT

INDUSTRY NAME
DCW Chemical Ltd, Sahupuram, Tuticorin (DT).

TRAINING DATE
18-JUN-2018 TO 22-JUN-2018.
 NAME OF THE TRAINEE
S. MAHAVISHNU
G. ARUMUGAN
T. NAVIN KUMAR
 DEPARTMENT
B. TECH, PETROCHEMICAL TECHNOLOGY.
 COLLEGE NAME
UNIVERSITY COLLEGE OF ENGINEERING,
BIT CAMPUS, TRICHY.
I
BLOCK DIAGRAM
NACL+H2O
FEED
SATURATING
TANK
PRECIPITATION
TANK
ION
EXCHANGE
CLARIFIER
POLISH
FILTER
ANTHRACITE
FILTER
ANOLYTE
FEED
CATHOLYTE
FEED
ELECTROLYSIS
48 %
NAOH
32%CAUSTIC
SODA
46 %
NAOH
38 %
NAOH
MULTIPLE EFFECT EVAPORATOR
48 % NAOH
TO BURNER
FUSION
PLANT
99 % NAOH
FLAKES AS
PRODUCTS
STORAGE
AND
PACKAGING
INTRODUCTION
DCW-LTD, TIRUCHENDUR MAIN ROAD, TUTICORIN.
COMPANY
NAME OF PLANT
CAUSTIC SODA PLANT
CAUSTIC SODA PLANT
INPLANT TRAINING DATE
18-JUN-2018 TO 22-JUN-2018
PERSONS CONTACTED
MR. GANAPATHI W.O
MR. KESAVAN HR
MR. RAJKUMAR SENIOR ENGINEER
MR. ARAVINTH GUIDE
DESCRIPTION OF PROCESS
FLOW SHEET
REFER BLOCK DIAGRAM OF CAUSTIC SODA PLANT.
RAW MATERIAL
NaCl SOLUTION OR BRINE SOLUTION- 305 gpl AND WATER.
CHEMICAL REACTIONS
NaCl + WATER
32% NaOH + H+ IONS + Cl- IONS MAIN RXN
Na2SO4 + BaCO3
BaSO4 + Na2CO3
SIDE RXN 1
CaCl2 + Na2CO3
CaCO3 + 2NaCl
SIDE RXN 2
MgCl2 + 2NaOH
2NaCl + MgOH2
SIDE RXN 3
PROCESS DESCRIPTION
INITIALLY THE FEED NACL SOLUTION OR BRINE SOLUTION PRETREATED BEFORE
ENTERING IN THE ELECTROLYSIS SECTION. WHERE 80% OF SUSPENDED SOLIDS REMOVED BY
ENTERING THE SATURATED SOLUTION INTO THE PRECIPITATION TANK (CSTR TANK) WHERE
BaCO3, Na2CO3 & NaOH ARE ADDED TO REMOVE THE SALT IMPURITIES SUCH AS Na2SO4,
CaCl2 & MgCl2. THEN THE SALT SOLUTION ENTER INTO THE CLARIFIER WHERE THE SETTLING
AGENT IS ADDED AND THE SLUDGE IS REMOVED (COMBINED FORM OF MgOH2 AND CaCO3).
THEN SENT FOR THE FURTHER FILTRATION PROCESSES LIKE ANTHRACITE FILTERATION
(ANTHRACITE- TYPE CARBON FILTER MEDIUM) & POLISH FILTERATION.ALL THE 80%
SUSPENDED SOLIDS REMOVED IN ABOVE PROCESSES.
NOW THE REMAINING 20% OF IMPURITIES PRESENT AS DISSOLVED FORM. THEN
THE DISSOLVED IMPURITIES REMOVED IN ION EXCHGANGER COLOUMN BY USIMG RESINS LIKE
RNa. AFTER FINISHING THE PREATREATMENT PROCESS WE GET 305 gpl BRINE SOLUTION FOR
NaOH PRODUCTION BY ELECTROLYSIS PROCESS.
TAKE THE BRINE SOLUTION IN ANODE SECTION AND WATER IN CATHODE
SECTION THEN START THE ELECTROLYSIS PROCESS, WHERE THE Na+ IONS PASS THROUGH THE
TEFLON MEMBRANE (HERE ONLY Na+ IONS PASSED THROUGH MEMBRANE REMAINING Cl- ONS
STAY IN THE ANODE SECTION) AND REACT WITH OH- TO GET 32% NaOH SOLUTION AS
PRODUCT FROM ELECTROLYSIS & CHLORINE AND HYDROGEN GAS TAKEN AS BYPRODUCTS.
ANODE TITANIUM
CATHODE NICKEL
ELECTROLYTIC MEMBRANE TEFLON
TO IMPROVE THE CONCENTRATION OF CAUSTIC SODA MULTIPLE EFFECT
EVAPOURATOR (FOR 48% NAOH SOLUTION) & FUSION PLANTS (99% NAOH FLAKES AND
PELLETS) ARE USED.
PRODUCTS
32% CAUSTIC SODA,
48% CAUSTIC SODA &
99% CAUSTIC SODA.
BYPRODUCTS
CHLORINE GAS &
HYDROGEN GAS.
SAFETY ASPECTS
PERSONAL PROTECTIVE EQUIPMENTS (PPE) SUCH AS HELMETS, GLOVES &
SHOES AND INDUSTRIAL PROCESS SAFETYS WERE HIGHLY PROTECTIVE ASPECTS DONE BY THE
SAFETY ENGINEERING DEPARTMENT IN THE COMPANY. FOR THE LAST ONE YEAR THE
COMPANY MAINTAINING ZERO MAJOR ACCIDENTAL RECORD AND 2 MINOR ACCIDENTAL
RECORD.
ENVIRONMENTAL POLLUTUION ASPECTS
NOX & SOX INTO THE ENVIRONMENT IN VERY LOW VALUE WHICH IS SAFE TO
THE SURROUNDING ENVIRONMENT. THESE ARE THE ASPECTS TAKEN IN CONSIDERATION BY
THE ENVIRONMENTAL DEPARMENT IN THE COMPANY TO AVOID POLLUTION TO THE
ENVIRONMENT.
APPLICATION AND USES OF CAUSTIC SODA
PULP INDUSTRY & PAPER INDUSTRY,
TEXTILE INDUSTRY,
DRINKING WATER,
SOAP & DETERGENTS,
DRAIN CLEANERS.