Industry Challenge

Catalyst

Catalyst is a substance that accelerates the desired chemical reaction for converting the reactants into products without getting consumed in the process.

In hydro-processing units, loading and unloading of catalyst in reactor is required for following reasons,

• Completion of catalyst life.
• Due to change of norms from MOP & NG
• Operational issues leading to change 

Catalyst Loading Steps

• In normal, following are the stage wise activities done in catalyst loading and inspection
• Inspection of reactor along with internals to ensure mechanical integrity of reactor prior to loading
• Ensuring correct grade and material is being taken to reactor via hopper.
• Checking the levelness of bed that is just loaded in the reactor.
• Calculation of density in each bed for main catalyst to ensuring entire catalyst is being loaded to the bed.
• Inspection of reactor internals and boxup of internal trays
• Inspection of reactor inlet diffuser and inlet elbow before box up of reactor. 

Sulfiding process of catalyst

• Sulfiding process is required to activate the metal sites of catalyst.
• Dimethyl Disulfide (DMDS) is the most commonly used chemical for sulfiding.
• DMDS when exposed to a hydrogen pressurized reactor generates hydrogen sulfide.
• Hydrogen sulfide participates in the sulfiding process to activate the catalyst.
• Sulfiding process is carried out based on the sulfiding charts of the particular catalyst.

The various sulfiding agents are:

• DMS (DiMethyl Sulfide)
• DMDS (DiMethyl DiSulfide)
• DMSO (DiMethyl Sulfoxide)
• TNPS (Tert Nonyl PolySulfide)
• Methyl Mercaptan

The advantages of sulfiding with DMDS

• High Sulfur Content (68%)
• Lowest Total Cost
• By-products will not cause premature coking
• Low Decomposition Temperature
• Chosen by Catalyst Manufactures for Activity Testing and Catalyst Development.

The various steps of sulfiding

• Purging of fresh catalyst loading with N2 to remove air (O2)
• Dehydrate the catalyst by heating.
• System is pressurized with hydrogen to the desired level.
• Start-up oil is introduced to soak the catalyst along with heating at slow rates.
• Introduction of Sulphiding agent and regular sample checks
• Completion of sulphiding as per the sulphiding charts

Post loading of catalyst, it has to be sulphided to

• To enhance the activity
• To control the hyperactivity as dealing with fresh catalyst

Usually, sulphiding is done with a spiking agent like DMDS, which makes product recycling possible and minimizes the duration of sulphiding independent of available feed. 

Factors which prompted BPCL to go for Remote Monitoring Solution

• The general practice was to reload the catalyst under the presence of supervisor assigned by catalyst supplier comprising of activities like inspection of the reactor internals, proper loading as per the loading diagram.
• Due to the prevailing COVID-19 global pandemic and the imposed travel restrictions, the physical presence of supervisors at site from distant overseas locations was not possible.
• Hence the idea of remote supervision using the digital platforms came into picture which enabled BPCL to provide live feed streaming of the entire activity that could be monitored from anywhere in the globe.

• Catalyst loading is a critical activity as it is linked to its performance guarantees which can be affected due to ineffective catalyst loading.

• DMDS skid operation is critical due to highly toxic and harmful nature to health and environment. Only specialized personnel are who are authorized to operate DMDS skid come to site and operate the DMDS container and skid
• Due to prevailing situation as it is not possible to get onsite supervision from both catalyst and DMDS suppliers, after a series of discussions and understanding it was decided to go for remote monitoring of catalyst loading for changing out catalyst and sulphiding of newly loaded catalyst in DHDS and VGOHDS unit.  

Advantages of digitalization for turnaround

• Proper surveillance of critical activities such as catalyst loading and unloading in reactors.
• Round the clock surveillance of activities carried out in inaccessible locations.
• Enhanced safety compliance due to improved surveillance.
• Reducing the down time of process units.
• Implementation of social distancing among workers without affecting the efficiency of turnaround.

Requirement

(1) BPCL has got multiple units in India where the process of Catalyst loading/unloading & Sulfiding is being done. They have integrated the remote monitoring solution in couple of their units and are looking forward to expand this solution implementation in other units across India. They are inviting solutions from the startups who are compatible enough to provide this solution.

(2) BPCL is seeking vendors who can (Startups/vendors with either both or any one of solution  listed below are invited to apply)

a. Supply the chemicals (DMDS) required for sulfiding

b. Provide sulfiding process as a service

1. For Remote Monitoring Solution (Catalyst unloading and loading in reactors, Sulphiding activity in both VGOHDS and DHDS), solution should meet following specifications

• A set of 5 cameras to be installed in each plant
• Remote monitoring from within country or abroad
• Along with live video streaming, a seamless 2-way communication link.

Catalyst Offloading / Loading Activity was under Plant Shutdown condition. Hence, following requirements are mandatory 

• Dust resistant
• Inert atmosphere
• High temperature, rain and electricity(24V) 

2. For chemicals supply and Sulfiding as a service

• Startup should be registered in India (& willing to register in Kerala)
• Should be a player in chemicals (for Sulfiding) distribution 
• Should be an expert in offering sulfiding as a service