Hindustan Zinc LimitedSummer Training Project

Presentation

HYDRO PLANT

Under Guidance of:Mr. Sandeep Gupta(Industry Guide)

Submitted By:MANISH SHARMAA2305411005MAE-1x

About HZL:Hindustan Zinc Ltd. (HZL) is a major producer of zinc, lead, and silver in the country. Huge quantity of Sulphuric acid is produced as a by-product of zinc and lead refining process which is marketed to different manufacturing industries.HZL is the world's second largest zinc producer.HZL is also the world's lowest cost zinc producerOPERATIONS:• SmeltingHZL operates Zinc and Lead smelters and refineries at Chanderiya (Chittorgarh), Debari (Udaipur) & Dariba (Rajsamand) in Rajasthan. A smelting facility was established at Pantnagar in Uttarakhand. It was initially intended to serve as a smelting facility for Silver production, but later Zinc and Lead melting and casting plants were also established here. • MiningHZL operates the world's third largest open-pit mine, and World's largest Zinc Mine in Rampura Agucha, Rajasthan. Other mines with HZL are located in Sindesar Khurd, Rajpura Dariba, Kayar and Zawar, all in Rajasthan.

SAFETY:

Hierarchy Of Control Measures:• Elimination• Substitution• Engineering Control• Administrative Control• PPE’s (Personal Protective Equipment)

Safety HelmetSafety Shoes

Hand Gloves

Chanderiya Smelting Plant:(Chittorgarh, Rajasthan)

Chanderiya Smelter Complex is the world's largest Lead-Zinc smelter complex in the Chittorgarh district of Rajasthan state of India. It is metallurgical type plant.It refines Lead-Zinc ore from Rampura Agucha. It produces Zinc, Lead, Silver, Cadmium and other precious metals.

It consists of 3 units:• Pyro Metallurgical Process Plant• Hydro Metallurgical Process Plant• Captive Power Plant

HYDRO PLANT PROCESS

• Consist 3 process :- 1) Roasting

ZnS + 2 ZnO + S 2) Leaching ZnO + S ZnS + O 3) Cell House ZnS+ O S+ Zn + ½

ROASTING

• Raw material coming from mines is handled and get conveyed from one place to other and we send it to roaster furnance where we get the Zn and then we convert it to Zn0.

• SO2 is produced and as it is harmful for us so we make it react with oxygen and gets converted into SO3 and it convert into H2SO4 and we use this in various purposes.

LEACHING

Process in leaching :- 1) Storage 2) Neutral Leaching 3) Hot Acid Leaching 4) Jarosite Precipitation 5) Pre- Neutralisation

1) STORAGE

• Solution (ZnO) comes from roaster and gets stored in leaching section.

• We store H2SO4 also which is coming from roaster plant.

2) Neutral Leaching

• It is the 1st process in this leaching section where we separate impurities from the calcine (ZnO).

• To convert zinc oxide into ZnSO4 , solution at 4.9-5 pH in presence of excess calcine so as to get minimum impurities in neutral overflow solution.

3) HOT ACID LEACHING

• Zinc oxide remained after leaching is leached at high tempertaures (90-95 ºC ) and acidity (30-40 gpl).

• Zinc ferrite formed during process is not leached, more aggressive leaching is required i.e. HOT ACID LEACHING II.

• We recover almost 97% of zinc from this process.

4) JAROSITE PRECIPIATATION

• It is required to remove the iron from ZnSO4 solution, which has leached during hot acid leaching II-stage. Ferrous is converted into ferric. This is done at high temp (100 ºC) and sodium sulphate addition is done as the result one complex of iron and sodium is formed known as Jarosite by adding sodium. The other impurities are also precipitated along with jarosite during this stage.

5) PRE- NEUTRALISATION

This stage is to collect the residual iron content in clear solution from jarosite before entering the neutral leaching, to precipitate impurities carried over from jarosite and neutralize the residual acid content. Calcine is added and pH-4.5-4.9 is maintained to precipitate iron as ferric hydroxide.

CELL HOUSE

Project-1Objective : Pneumatic Conveying Of Zinc Dust in Purification.

Pneumatic Conveying:A pneumatic conveying system transfers powders, granules, and other dry materials through an enclosed horizontal or vertical conveying line. The motive force for this transfer comes from a combination of pressure differential and the flow of air supplied by an air mover, such as a blower or fan. By controlling the pressure and the airflow inside the conveying line, the system can successfully convey materials.Zinc Dust Plant:It is designed to produce the zinc dust, which is required at the purification and cadmium plant. Two atomising furnaces are provided, each having a dust production capacity of 1200 kg/h. This plant will be an integrated plant of the melting and casting plant and will consist of the following main equipment:• One 600 kW induction furnace• One double expansion chamber / bin• One double deck zinc dust screen• Two zinc dust bins, one for coarse and one for fine dust with the corresponding

pneumatic zinc dust transport system

Different Components of pneumatic conveying Unit:• Expansion Chamber/ Bins• Vibrating Feeders• Bucket Elevators• Bag Filter• Vibrating Screen• Molten Metal Launder• Furnace ventilation Baghouse

PROJECT-2 OBJECTIVE: Installation of rotary control valves for calcine silos.

ROTARY VALVE• Rotary Control Valves are eccentric valves for throttling liquids,

gases and slurries. They combine precise throttling accuracy and control over a full 90° of rotation.

• Rotary Control Valves are designed for bi-directional flow capability and include four trim options for flexibility.

• Designed for ease of maintenance with no internal threaded components and self-aligning seat and plug.

• In industry, a rotary valve (which can also be called airlock) is often used to enter or extract material from two chambers with different pressure level.

Why Rotary Valves?

• Before we were using reciprocating control valves by using screw compressors but in that there were so many leakage points.

• We used rotary control valves to minimize the leakage and increasing the efficiency as there is only one point of leakage i.e. shaft.

PROJECT-3 OBJECTIVE: Development of alternate ac for kunz crane (used to lift electrodes in cellhouse)

Equipment layout:-The air conditioning unit consists of two parts, the mechanical section and the actual air conditioning section.

• Mechanical Section: It consists of a robust steel casing with removable casing plates. It houses the main components, i.e. condenser, refrigerant tank and the

necessary refrigerant lines and fittings. On the side opposite to the condenser the casing is in the form of a

grating, allowing the heated exhaust air to escape. The belt pulleys on compressor and drive motor are fixed on the shaft

with Taper-Lock bushes, allowing for easy mounting.

• Air conditioning section:- The air conditioning section consists

of an insulated steel plate housing accomodating the evaporator (air cooler), air recirculation fan, electrical heating, switch cabinet, stage thermostat, fresh air filter, expansion valve and the pressure switches.

Three sides of the housing are formed by removable, insulated covers , affording easy access to the inside of the air conditioning section for maintenance work.

All three may be switched round at will, allowing a variety of arrangements for the air connections as already mentioned.

THANK YOU